U.S. patent application number 15/752696 was filed with the patent office on 2020-07-02 for metal amides for use as hil for an organic light-emitting diode (oled).
The applicant listed for this patent is Novaled GmbH. Invention is credited to Markus Hummert, Thomas Rosenow.
Application Number | 20200212337 15/752696 |
Document ID | / |
Family ID | 53900756 |
Filed Date | 2020-07-02 |
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United States Patent
Application |
20200212337 |
Kind Code |
A2 |
Hummert; Markus ; et
al. |
July 2, 2020 |
Metal Amides for Use as HIL for an Organic Light-Emitting Diode
(OLED)
Abstract
The present invention relates to metal amides of general Formula
Ia and for their use as hole injection layer (HIL) for an Organic
light-emitting diode (OLED), and a method of manufacturing Organic
light-emitting diode (OLED) comprising an hole injection layer
containing a metal amide of general Formula Ia: ##STR00001##
Inventors: |
Hummert; Markus; (Dresden,
DE) ; Rosenow; Thomas; (Dresden, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Novaled GmbH |
Dresden |
|
DE |
|
|
Prior
Publication: |
|
Document Identifier |
Publication Date |
|
US 20180240996 A1 |
August 23, 2018 |
|
|
Family ID: |
53900756 |
Appl. No.: |
15/752696 |
Filed: |
August 18, 2016 |
PCT Filed: |
August 18, 2016 |
PCT NO: |
PCT/EP2016/069638 PCKC 00 |
371 Date: |
February 14, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01L 51/005 20130101;
H01L 51/5088 20130101; H01L 51/0083 20130101; H01L 51/0091
20130101; H01L 51/0078 20130101; H01L 51/0053 20130101; H01L
51/5084 20130101; H01L 51/0059 20130101; H01L 51/006 20130101; H01L
51/5068 20130101; H01L 51/0079 20130101 |
International
Class: |
H01L 51/50 20060101
H01L051/50 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 18, 2015 |
EP |
15181385.4 |
Claims
1. A hole injection layer for an OLED comprising a charge neutral
metal amide compound, characterized in that the charge neutral
metal amide compound has the Formula Ia: ##STR00202## wherein:
G=halide, O, alkoxylate or amine of Formula IIa to IIe:
##STR00203## R.sup.1 to R.sup.5 are independently selected from the
group comprising H, C.sub.1 to C.sub.20 alkyl, C.sub.1 to C.sub.20
heteroalkyl, unsubstituted or C.sub.1 to C.sub.12 substituted
C.sub.6 to C.sub.20 aryl, unsubstituted or C.sub.1 to C.sub.12
substituted heteroaryl with 5 to 20 ring-forming atoms, halogenated
or perhalogenated C.sub.1 to C.sub.20 alkyl, halogenated or
perhalogenated C.sub.1 to C.sub.20 heteroalkyl, halogenated or
perhalogenated C.sub.6 to C.sub.20 aryl, halogenated or
perhalogenated heteroaryl with 5 to 20 ring-forming atoms; or at
least one R.sup.1 and R.sup.4 and/or R.sup.2 and R.sup.3 and/or
R.sup.1 and R.sup.5 are bridged and form a 5 to 20 member ring;
m=0, 1, 2, 3 or 4; M=a metal selected from the group comprising
alkali metal, alkaline earth metal, Al, Ga, In, transition metal or
rare earth metal; wherein the bond between N and the metal M is a
covalent bond or N forms a non-covalent interaction to the metal M;
L=charge neutral ligand which coordinates to the metal M, selected
from the group comprising H.sub.2O, C.sub.2 to C.sub.40 mono- or
multi-dentate ethers and C.sub.2 to C.sub.40 thioethers, C.sub.2 to
C.sub.40 amines, C.sub.2 to C.sub.40 phosphine, C.sub.2 to C.sub.20
alkyl nitrile or C.sub.2 to C.sub.40 aryl nitrile, or a compound
according to Formula (III); ##STR00204## wherein R.sup.6 and
R.sup.7 are independently selected from C.sub.1 to C.sub.20 alkyl,
C.sub.1 to C.sub.20 heteroalkyl, C.sub.6 to C.sub.20 aryl,
heteroaryl with 5 to 20 ring-forming atoms, halogenated or
perhalogenated C.sub.1 to C.sub.20 alkyl, halogenated or
perhalogenated C.sub.1 to C.sub.20 heteroalkyl, halogenated or
perhalogenated C.sub.6 to C.sub.20 aryl, halogenated or
perhalogenated heteroaryl with 5 to 20 ring-forming atoms, or at
least one R.sup.6 and R.sup.7 are bridged and form a 5 to 20 member
ring, or the two R.sup.6 and/or the two R.sup.7 are bridged and
form a 5 to 40 member ring or form a 5 to 40 member ring comprising
an unsubstituted or C.sub.1 to C.sub.12 substituted phenanthroline;
p=0, 1, 2 or 3; A.sup.1, A.sup.2, A.sup.3 and A.sup.4 are
independently selected from CO, SO.sub.2 or POR.sup.8;
R.sup.8=electron withdrawing group selected from the group
comprising halide, nitrile, halogenated or perhalogenated C.sub.1
to C.sub.20 alkyl, halogenated or perhalogenated C.sub.6 to
C.sub.20 aryl, or halogenated or perhalogenated heteroaryl with 5
to 20 ring-forming atoms; n=1, 2, 3, 4 or 5; B.sup.1, B.sup.2,
B.sup.3 and B.sup.4 are same or independently selected from
substituted or unsubstituted C.sub.1 to C.sub.20 alkyl, substituted
or unsubstituted C.sub.1 to C.sub.20 heteroalkyl, substituted or
unsubstituted C.sub.6 to C.sub.20 aryl, substituted or
unsubstituted C.sub.5 to C.sub.20 heteroaryl, or B.sup.1 and
B.sup.2 are bridged; wherein B.sup.1 and B.sup.2 are bridged, then:
M, N, A.sup.1, B.sup.1, B.sup.2, A.sup.2 and N form a 7 to 10
member ring according to Formula Ib; ##STR00205## or N, A.sup.1,
B.sup.1, B.sup.2 and A.sup.2 form a 5 to 10 member ring according
to Formula Ic, ##STR00206## or N, A.sup.1, B.sup.1, B.sup.2 and
A.sup.2 form a first 5 to 10 member ring and B.sup.1 and B.sup.2
form a second 5 to 20 member ring according to Formula Id:
##STR00207##
2. The hole injection layer according to claim 1, wherein the
charge neutral metal amide compound has the Formula Ia,
##STR00208## wherein: A.sup.1 and A.sup.2 are same or independently
selected from CO, POR.sup.8 and SO.sub.2; or A.sup.1 and A.sup.2
are independently selected from CO, POR.sup.8, SO.sub.2, and N,
A.sup.1, B.sup.1, A.sup.2 and B.sup.2 form a 5 to 10 member
ring.
3. The hole injection layer according to any of claim 1, wherein
for: p=0, m=1, 2, 3 or 4 and n=1, 2, 3 or 4, the charge neutral
metal amide compound has the Formula IIa: ##STR00209## or p=1, 2 or
3, and n=1, 2, 3 or 4 and m=0, the charge neutral metal amide
compound has the Formula IIb: ##STR00210## or p=1, 2 or 3, n=1, 2,
3 or 4, m=1, 2, 3 or 4 and N, A.sup.1, B.sup.1, B.sup.2 and A.sup.2
form a 5 to 10 member ring, the charge neutral metal amide compound
has the Formula IIc: ##STR00211## or p=1, 2 or 3, n=1, 2, 3 or 4,
m=1, 2, 3 or 4 and N, A.sup.1, B.sup.1, B.sup.2 and A.sup.2 form a
first 5 to 10 member ring and B.sup.1 and B.sup.2 are bridged to
form a second 5 to 20 member ring, the charge neutral metal amide
compound has the Formula IId: ##STR00212## or p=1, 2 or 3, n=1,
m=1, 2, 3 or 4, and M, N, A.sup.1, B.sup.1, B.sup.2, A.sup.2 and N
form a 7 to 10 member ring, the charge neutral metal amide compound
has the Formula IIe: ##STR00213## p=1, 2 or 3, n=1, 2, 3 or 4, m=0
and N, A, B.sup.1, B.sup.2 and A.sup.2 form a 5 to 10 member ring,
the charge neutral metal amide compound has the Formula IIf:
##STR00214## p=1, 2 or 3, n=1, 2, 3 or 4, m=0 and N, A, B.sup.1,
B.sup.2 and A.sup.2 form a first 5 to 10 member ring, and B.sup.1
and B.sup.2 are bridged to form a second 5 to 20 member ring, the
charge neutral metal amide compound has the Formula IIg:
##STR00215## p=1, 2 or 3, n=1, m=0 and M, N, A.sup.1, B.sup.1,
B.sup.2, A.sup.2 and N form a 7 to 10 member ring, the charge
neutral metal amide compound has the Formula IIh: ##STR00216##
4. The hole injection layer according to claim 1, wherein for
A.sup.1 and A.sup.2 are SO.sub.2: p=1, 2 or 3, n=1, 2, 3 or 4, m=1,
2, 3 or 4, the charge neutral metal amide compound has the Formula
IIIa: ##STR00217## p=0, n=1, 2, 3 or 4, m=1, 2, 3 or 4, the charge
neutral metal amide compound has the Formula IIIb: ##STR00218##
p=1, 2 or 3, n=1, 2, 3 or 4, m=0, the charge neutral metal amide
compound has the Formula IIIc: ##STR00219## p=1, 2 or 3, n=1, 2, 3
or 4, m=1, 2, 3 or 4 and N, SO.sub.2, B.sup.1, B.sup.2 and SO.sub.2
form a 5 to 10 member ring, the charge neutral metal amide compound
has the Formula IIId: ##STR00220## p=1, 2 or 3, n=1, 2, 3 or 4,
m=1, 2, 3 or 4 and N, SO.sub.2, B.sup.1, B.sup.2 and SO.sub.2 form
a first 5 to 10 member ring, and B.sup.1 and B.sup.2 are bridged to
form a second 5 to 20 member ring, the charge neutral metal amide
compound has the Formula IIIe: ##STR00221## p=1, 2 or 3, n=1, m=1,
2, 3 or 4 and M, N, SO.sub.2, B.sup.1, B.sup.2, SO.sub.2 and N form
a 7 to 10 member ring, the charge neutral metal amide compound has
the Formula IIIf: ##STR00222## p=1, 2 or 3, n=1, 2, 3 or 4, m=0 and
N, SO.sub.2, B.sup.1, B.sup.2 and SO.sub.2 form a 5 to 10 member
ring, the charge neutral metal amide compound has the Formula IIIg:
##STR00223## p=1, 2 or 3, n=1, 2, 3 or 4, m=0 and N, SO.sub.2,
B.sup.1, B.sup.2 and SO.sub.2 form a first 5 to 10 member ring, and
B.sup.1 and B.sup.2 are bridged to form a second 5 to 20 member
ring, the charge neutral metal amide compound has the Formula IIIh:
##STR00224## p=1, 2 or 3, n=1, 2, 3 or 4, m=0 and M, N, SO.sub.2,
B.sup.1, B.sup.2, SO.sub.2 and N form a 7 to 10 member ring, the
charge neutral metal amide compound has the Formula IIIi:
##STR00225## wherein for A.sup.1 and A.sup.2 are POR.sup.8: p=1, 2
or 3, m=1, 2, 3 or 4 and n=1, 2, 3 or 4, the charge neutral metal
amide compound has the Formula IVa: ##STR00226## p=0, m=1, 2, 3 or
4 and n=1, 2, 3 or 4, the charge neutral metal amide compound has
the Formula IVb: ##STR00227## p=1, 2 or 3, m=0 and n=1, 2, 3 or 4,
the charge neutral metal amide compound has the Formula IVc:
##STR00228## p=1, 2 or 3, n=1, 2, 3 or 4, m=1, 2, 3 or 4 and N,
POR.sup.8, B.sup.1, B.sup.2 and POR.sup.8 form a 5 to 10 member
ring, the charge neutral metal amide compound has the Formula
(IVd): ##STR00229## p=1, 2 or 3, n=1, 2, 3 or 4, m=0 and N,
POR.sup.8, B.sup.1, B.sup.2 and POR.sup.8 form a 5 to 10 member
ring, the charge neutral metal amide compound has the Formula
(IVe): ##STR00230## wherein for A.sup.1 and A.sup.2 are CO: p=1, 2
or 3, m=1, 2, 3 or 4 and n=1, 2, 3 or 4, the charge neutral metal
amide compound has the Formula Va: ##STR00231## p=0, n=1, 2, 3 or
4, m=1, 2, 3 or 4, the charge neutral metal amide compound has the
Formula Vb: ##STR00232## p=1, 2 or 3, n=1, 2, 3 or 4, m=0, the
charge neutral metal amide compound has the Formula Vc:
##STR00233## p=1, 2 or 3, n=1, 2, 3 or 4, m=1, 2, 3 or 4 and N, CO,
B.sup.1, B.sup.2 and CO form a 5 to 10 member ring, the charge
neutral metal amide compound has the Formula Vd: ##STR00234## p=1,
2 or 3, n=1, 2, 3 or 4, m=1, 2, 3 or 4 and N, CO, B.sup.1, B.sup.2
and CO form a first 5 to 10 member ring, and B.sup.1 and B.sup.2
are bridged to form a second 5 to 20 member ring, the charge
neutral metal amide compound has the Formula Ve: ##STR00235## p=1,
2 or 3, n=1, m=1, 2, 3 or 4 and M, N, CO, B.sup.1, B.sup.2, CO and
N form a 7 to 10 member ring, the charge neutral metal amide
compound has the Formula Vf: ##STR00236## p=1, 2 or 3, n=1, 2, 3 or
4, m=0 and N, CO, B.sup.1, B.sup.2 and CO form a 5 to 10 member
ring, the charge neutral metal amide compound has the Formula (Vg):
##STR00237## p=1, 2 or 3, n=1, 2, 3 or 4, m=0 and N, CO, B.sup.1,
B.sup.2 and CO form a first 5 to 10 member ring, and B.sup.1 and
B.sup.2 form a second 5 to 20 member ring, the charge neutral metal
amide compound has the Formula Vh: ##STR00238## p=1, 2 or 3, n=1,
2, 3 or 4, m=0 and M, N, CO, B.sup.1, B.sup.2, CO and N form a 7 to
10 member ring, the charge neutral metal amide compound has the
Formula (Vi): ##STR00239## or wherein for A.sup.1 is SO.sub.2 and
A.sup.2 is POR.sup.8: p=1, 2 or 3, m=1, 2, 3 or 4 and n=1, 2, 3 or
4, the charge neutral metal amide compound has the Formula VIa:
##STR00240##
5. The hole injection layer according to claim 1, wherein B.sup.1,
B.sup.2, B.sup.3 and B.sup.4 are independently selected from a
substituted C.sub.1 to C.sub.20 alkyl, substituted C.sub.1 to
C.sub.20 heteroalkyl, substituted C.sub.6 to C.sub.20 aryl, or
substituted C.sub.5 to C.sub.20 heteroaryl; wherein the substituent
is an electron withdrawing group selected from the group comprising
a halide, nitrile, perhalogenated C.sub.1 to C.sub.20 alkyl,
perhalogenated C.sub.6 to C.sub.20 aryl, perhalogenated heteroaryl
with 6 to 20 ring-forming atoms.
6. The hole injection layer according to claim 1, wherein m=0, 1 or
2.
7. The hole injection layer according to claim 1, wherein M is
selected from Li(I), Na(I), K(I), Cs(I), Mg(II), Ca(II), Sr(II),
Ba(II), Sc(III), Y(III), Ti(IV), V(III-V), Cr(III-VI), Mn(II),
Mn(III), Fe(II), Fe(III), Co(II), Co(III), Ni(II), Cu(I), Cu(II),
Zn(II), Ag(I), Au(I), Au(III), Al(III), Ga(III), In(III), Sn(II),
Sn(IV), or Pb(II).
8. The hole injection layer according to claim 1, wherein the
charge neutral metal amide compound has the Formula Ib:
##STR00241## wherein A.sup.3 and A.sup.4 are same or independently
selected from CO, POR.sup.8 or SO.sub.2; B.sup.3 and B.sup.4 are
independently selected from substituted or unsubstituted C.sub.1 to
C.sub.20 alkyl, substituted or unsubstituted C.sub.1 to C.sub.20
heteroalkyl, substituted or unsubstituted C.sub.6 to C.sub.20 aryl,
substituted or unsubstituted C.sub.6 to C.sub.20 heteroaryl; and M,
N, A.sup.1, B.sup.1, A.sup.2 and B.sup.2 form a 7 to 10 member
ring.
9. The hole injection layer according to claim 1, wherein N,
A.sup.1, B.sup.1, A.sup.2 and B.sup.2 form a first 5 to 10 member
ring and B.sup.1 and B.sup.2 according to Formula Id: ##STR00242##
are bridged to form a second ring of a substituted or unsubstituted
C.sub.6 to C.sub.20 aryl, or of a substituted or unsubstituted
C.sub.6 to C.sub.20 heteroaryl ring.
10. The hole injection layer according to claim 1, wherein the
charge neutral metal amide compound is selected from at least one
of the fluorinated compounds according to Formula C1 to C25:
wherein Formula C1 to C16, wherein p=0, m=0, n=1, 2, 3 or 4 and
A.sup.1 and A.sup.2 are SO.sub.2: ##STR00243## ##STR00244##
##STR00245## Formula C17 to C23, wherein n=1, 2, 3 or 4, A.sup.1
and A.sup.2 are CO: ##STR00246## ##STR00247## Formula C24 to C25,
wherein n=1, 2, 3 or 4, A.sup.1 and A.sup.2 are POR.sup.8:
##STR00248##
11. The hole injection layer according to claim 1, wherein the
charge neutral metal amide compound is selected from at least one
fluorinated compound according to Formula D1 to D24: wherein p=0,
m=0, n=1, 2, 3 or 4 and A.sup.1 and A.sup.2 are SO.sub.2:
##STR00249## ##STR00250## ##STR00251## ##STR00252##
12. The hole injection layer according to claim 1, wherein the
charge neutral metal amide compound is selected from at least one
fluorinated compound according to Formula F1 to F23: wherein the
charge neutral ligand L coordinates to the metal M: ##STR00253##
##STR00254## ##STR00255## ##STR00256## wherein R.sup.6 and R.sup.7
are independently selected from C.sub.1 to C.sub.20 alkyl, C.sub.1
to C.sub.20 heteroalkyl, C.sub.6 to C.sub.20 aryl, heteroaryl with
5 to 20 ring-forming atoms, halogenated or perhalogenated C.sub.1
to C.sub.20 alkyl, halogenated or perhalogenated C.sub.1 to
C.sub.20 heteroalkyl, halogenated or perhalogenated C.sub.6 to
C.sub.20 aryl, halogenated or perhalogenated heteroaryl with 5 to
20 ring-forming atoms, or at least one R.sup.6 and R.sup.7 are
bridged and form a 5 to 20 member ring, or the two R.sup.6 and/or
the two R.sup.7 are bridged and form a 5 to 40 member ring or form
a 5 to 40 member ring comprising an unsubstituted or C.sub.1 to
C.sub.12 substituted phenanthroline.
13. The hole injection layer according to claim 1, wherein the
charge neutral metal amide compound is selected from at least one
fluorinated compound according to Formula F24 to F45: wherein a
halide, O, alkoxylate or amine bonds to the metal M: ##STR00257##
##STR00258## ##STR00259## ##STR00260## wherein R.sup.1 to R.sup.5
are independently selected from the group comprising H, C.sub.1 to
C.sub.20 alkyl, C.sub.1 to C.sub.20 heteroalkyl, unsubstituted or
C.sub.1 to C.sub.12 substituted C.sub.6 to C.sub.20 aryl,
unsubstituted or C.sub.1 to C.sub.12 substituted heteroaryl with 5
to 20 ring-forming atoms, halogenated or perhalogenated C.sub.1 to
C.sub.20 alkyl, halogenated or perhalogenated C.sub.1 to C.sub.20
heteroalkyl, halogenated or perhalogenated C.sub.6 to C.sub.20
aryl, halogenated or perhalogenated heteroaryl with 5 to 20
ring-forming atoms; or at least one R.sup.1 and R.sup.4 and/or
R.sup.2 and R.sup.3 and/or R.sup.1 and R.sup.5 are bridged and form
a 5 to 20 member cyclic ring.
14. (canceled)
15. An OLED comprising a hole injection layer according to claim 1
and an emission layer.
16. An OLED according to claim 15, comprising: an anode, a hole
injection layer and an emission layer, wherein the hole injection
layer is in direct contact to the anode and the emission layer is
in direct contact to the hole injection layer
17. (canceled)
18. An OLED according to claim 15, comprising: an anode, a hole
injection layer, a hole transport layer and an emission layer,
wherein the hole injection layer is in direct contact to the anode
and the hole transport layer is in direct contact to the hole
injection layer; and the composition of the hole injection layer is
different to the composition of the hole transport layer.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a U.S. national stage application of
PCT/EP2016/069638, filed Aug. 18, 2016, which claims priority to
European Application No. 15181385.4, filed Aug. 18, 2015.
[0002] The content of these applications is hereby incorporated by
reference.
DESCRIPTION
[0003] The present invention relates to metal amides for use as
hole injection layer (HIL) for an Organic light-emitting diode
(OLED), and a method of manufacturing Organic light-emitting diode
(OLED) comprising the metal amide containing HIL.
DESCRIPTION OF THE RELATED ART
[0004] Organic solar cell as disclosed in EP 1 209 708 A1 having
the general structure:
substrate+EM/HTM/dye/SOL/EM, or substrate+EM/SOL/dye/HTM/EM, or
substrate+EM/HTM/SOL/EM, in which EM is the electrode material that
may be a transparent conductive oxide (TCO) or metal, with at least
one of the EM layer(s) of the cell being a TCO, HTM is the hole
transport material, SOL is a semiconducting oxide layer, "dye" is a
suitable dye, and the SOL layer is vapor deposited.
[0005] US 2013/0330632 A1 refers to electrochemical devices
comprising complexes of cobalt comprising at least one ligand with
a 5- or six membered, N-containing heteroring. The complex are
useful as p- and n-dopants, as over of electrochemical devices, in
particular in organic semiconductors. The complexes are further
useful as over-discharge prevention and overvoltage protection
agents.
[0006] Organic light-emitting diodes (OLEDs), which are
self-emitting devices, have a wide viewing angle, excellent
contrast, quick response, high brightness, excellent driving
voltage characteristics, and color reproduction. A typical OLED
includes an anode, a hole injection layer (HIL), a hole transport
layer (HTL), an emission layer (EML), an electron transport layer
(ETL), and a cathode, which are sequentially stacked on a
substrate. In this regard, the HIL, the HTL, the EML, and the ETL
are thin films formed from organic compounds.
[0007] When a voltage is applied to the anode and the cathode,
holes injected from the anode move to the EML, via the HIL and HTL,
and electrons injected from the cathode move to the EML, via the
ETL. The holes and electrons recombine in the EML to generate
excitons. When the excitons drop from an excited state to a ground
state, light is emitted. The injection and flow of holes and
electrons should be balanced, so that an OLED having the
above-described structure has excellent efficiency and/or a long
lifetime.
[0008]
Dipyrazino[2,3-f:2',3'-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile
(CNHAT (CAS 105598-27-4)) having the Formula A, which is typically
used as hole injection layer has several drawbacks.
##STR00002##
[0009] For example, if the HOMO level of the hole transport layer
of an OLED comprising a CNHAT HIL-layer is further away from the
vacuum level, the voltage of the OLED is too high. Further,
effective hole injection even into very deep HOMO HTLs, that means
the HOMO is further away from vacuum level, is not sufficiently
achieved.
[0010] Efficient hole injection into very deep HOMO levels enables
the use of high efficiency emission layers, in particular
phosphorescent blue and green emitters and emission which relies on
TADF (thermally activated delayed fluorescence).
[0011] Thus, it is still desired to provide a hole injection layer
material that more effectively promotes the hole injection over a
broader range of HOMO levels to vacuum level from the HIL-layer
into the hole transport layer (HTL).
SUMMARY
[0012] Aspects of the present invention provide a method of
reducing the drive voltage and improving the voltage stability over
time, especially for blue emitting OLEDs, and/or the external
quantum efficiency EQE, for top and/or bottom emission organic
light-emitting diodes (OLED). The invention relates to a hole
injection layer (HIL) for use for an Organic light-emitting diode
(OLED). The invention relates further to an organic light-emitting
diode (OLED) comprising an anode, a hole injection layer (HIL), a
hole transport layer (HTL), an emission layer (EML), optional a
hole blocking layer (HBL), optional an electron transport layer
(ETL), optional an electron injection layer (EIL), and a cathode as
well as a method of manufacturing the same.
[0013] According to an aspect of the present invention, there is
provided a hole injection layer for an OLED comprising a charge
neutral metal amide compound, wherein the charge neutral metal
amide compound has the Formula Ia:
##STR00003##
wherein: [0014] G=halide, O, alkoxylate or amine of Formula IIa to
IIe:
[0014] ##STR00004## [0015] R.sup.1 to R.sup.5 are independently
selected from the group comprising H, C.sub.1 to C.sub.20 alkyl,
C.sub.1 to C.sub.20 heteroalkyl, unsubstituted or C.sub.1 to
C.sub.12 substituted C.sub.6 to C.sub.20 aryl, unsubstituted or
C.sub.1 to C.sub.12 substituted heteroaryl with 5 to 20
ring-forming atoms, halogenated or perhalogenated C.sub.1 to
C.sub.20 alkyl, halogenated or perhalogenated C.sub.1 to C.sub.20
heteroalkyl, halogenated or perhalogenated C.sub.6 to C.sub.20
aryl, halogenated or perhalogenated heteroaryl with 5 to 20
ring-forming atoms; or [0016] at least one R.sup.1 and R.sup.4
and/or R.sup.2 and R.sup.3 and/or R.sup.1 and R.sup.5 are bridged
and form a 5 to 20 member ring; [0017] m=0, 1, 2, 3 or 4; [0018]
M=a metal selected from the group comprising alkali metal, alkaline
earth metal, Al, Ga, In, transition metal or rare earth metal;
[0019] L=charge neutral ligand which coordinates to the metal M,
selected from the group comprising H.sub.2O, C.sub.2 to C.sub.40
mono- or multi-dentate ethers and C.sub.2 to C.sub.40 thioethers,
C.sub.2 to C.sub.40 amines, C.sub.2 to C.sub.40 phosphine, C.sub.2
to C.sub.20 alkyl nitrile or C.sub.2 to C.sub.40 aryl nitrile, or a
compound according to Formula (III);
[0019] ##STR00005## [0020] wherein R.sup.6 and R.sup.7 are
independently selected from C.sub.1 to C.sub.20 alkyl, C.sub.1 to
C.sub.20 heteroalkyl, C.sub.6 to C.sub.20 aryl, heteroaryl with 5
to 20 ring-forming atoms, halogenated or perhalogenated C.sub.1 to
C.sub.20 alkyl, halogenated or perhalogenated C.sub.1 to C.sub.20
heteroalkyl, halogenated or perhalogenated C.sub.6 to C.sub.20
aryl, halogenated or perhalogenated heteroaryl with 5 to 20
ring-forming atoms, or at least one R.sup.6 and R.sup.7 are bridged
and form a 5 to 20 member ring, or the two R.sup.6 and/or the two
R.sup.7 are bridged and form a 5 to 40 member ring or form a 5 to
40 member ring comprising an unsubstituted or C.sub.1 to C.sub.12
substituted phenanthroline; [0021] p=0, 1, 2 or 3; [0022] A.sup.1,
A.sup.2, A.sup.3 and A.sup.4 are independently selected from CO,
SO.sub.2 or POR.sup.8; [0023] R.sup.8=electron withdrawing group
selected from the group comprising halide, nitrile, halogenated or
perhalogenated C.sub.1 to C.sub.20 alkyl, halogenated or
perhalogenated C.sub.6 to C.sub.20 aryl, or halogenated or
perhalogenated heteroaryl with 5 to 20 ring-forming atoms; [0024]
n=1, 2, 3, 4 or 5; [0025] B.sup.1, B.sup.2, B.sup.3 and B.sup.4 are
same or independently selected from substituted or unsubstituted
C.sub.1 to C.sub.20 alkyl, substituted or unsubstituted C.sub.1 to
C.sub.20 heteroalkyl, substituted or unsubstituted C.sub.6 to
C.sub.20 aryl, substituted or unsubstituted C.sub.5 to C.sub.20
heteroaryl, or B.sup.1 and B.sup.2 are bridged; wherein B.sup.1 and
B.sup.2 are bridged, then: [0026] M, N, A.sup.1, B.sup.1, B.sup.2,
A.sup.2 and N form a 7 to 10 member ring according to Formula
Ib;
##STR00006##
[0026] or [0027] N, A.sup.1, B.sup.1, B.sup.2 and A.sup.2 form a 5
to 10 member ring according to Formula Ic,
##STR00007##
[0027] or [0028] N, A.sup.1, B.sup.1, B.sup.2 and A.sup.2 form a
first 5 to 10 member ring and B.sup.1 and B.sup.2 form a second 5
to 20 member ring according to Formula Id:
##STR00008##
[0029] According to another aspect of the present invention, there
is provided a hole injection layer for an OLED comprising a charge
neutral metal amide compound, wherein the charge neutral metal
amide compound has the Formula Ia:
##STR00009##
wherein: [0030] G=halide, O, alkoxylate or amine of Formula IIa to
IIe:
[0030] ##STR00010## [0031] R.sup.1 to R.sup.5 are independently
selected from the group comprising H, C.sub.1 to C.sub.20 alkyl,
C.sub.1 to C.sub.20 heteroalkyl, unsubstituted or C.sub.1 to
C.sub.12 substituted C.sub.6 to C.sub.20 aryl, unsubstituted or
C.sub.1 to C.sub.12 substituted heteroaryl with 5 to 20
ring-forming atoms, halogenated or perhalogenated C.sub.1 to
C.sub.20 alkyl, halogenated or perhalogenated C.sub.1 to C.sub.20
heteroalkyl, halogenated or perhalogenated C.sub.6 to C.sub.20
aryl, halogenated or perhalogenated heteroaryl with 5 to 20
ring-forming atoms; or [0032] at least one R.sup.1 and R.sup.4
and/or R.sup.2 and R.sup.3 and/or R.sup.1 and R.sup.5 are bridged
and form a 5 to 20 member ring; [0033] m=0, 1, 2, 3 or 4; [0034]
M=a metal selected from the group comprising alkali metal, alkaline
earth metal, Al, Ga, In, transition metal or rare earth metal;
[0035] L=charge neutral ligand which coordinates to the metal M,
selected from the group comprising H.sub.2O, C.sub.2 to C.sub.40
mono- or multi-dentate ethers and C.sub.2 to C.sub.40 thioethers,
C.sub.2 to C.sub.40 amines, C.sub.2 to C.sub.40 phosphine, C.sub.2
to C.sub.20 alkyl nitrile or C.sub.2 to C.sub.40 aryl nitrile, or a
compound according to Formula (III);
[0035] ##STR00011## [0036] wherein R.sup.6 and R.sup.7 are
independently selected from C.sub.1 to C.sub.20 alkyl, C.sub.1 to
C.sub.20 heteroalkyl, C.sub.6 to C.sub.20 aryl, heteroaryl with 5
to 20 ring-forming atoms, halogenated or perhalogenated C.sub.1 to
C.sub.20 alkyl, halogenated or perhalogenated C.sub.1 to C.sub.20
heteroalkyl, halogenated or perhalogenated C.sub.6 to C.sub.20
aryl, halogenated or perhalogenated heteroaryl with 5 to 20
ring-forming atoms, or at least one R.sup.6 and R.sup.7 are bridged
and form a 5 to 20 member ring, or the two R.sup.6 and/or the two
R.sup.7 are bridged and form a 5 to 40 member ring or form a 5 to
40 member ring comprising an unsubstituted or C.sub.1 to C.sub.12
substituted phenanthroline; [0037] p=0, 1, 2 or 3; [0038] A.sup.1,
A.sup.2, A.sup.3 and A.sup.4 are independently selected from CO,
SO.sub.2 or POR.sup.8; [0039] R.sup.8=electron withdrawing group
selected from the group comprising halide, nitrile, halogenated or
perhalogenated C.sub.1 to C.sub.20 alkyl, halogenated or
perhalogenated C.sub.6 to C.sub.20 aryl, or halogenated or
perhalogenated heteroaryl with 5 to 20 ring-forming atoms; [0040]
n=1, 2, 3, 4 or 5; [0041] B.sup.1, B.sup.2, B.sup.3 and B.sup.4 are
same or independently selected from substituted or unsubstituted
C.sub.1 to C.sub.20 alkyl, substituted or unsubstituted C.sub.1 to
C.sub.20 heteroalkyl, substituted or unsubstituted C.sub.6 to
C.sub.20 aryl, substituted or unsubstituted C.sub.5 to C.sub.20
heteroaryl, or B.sup.1 and B.sup.2 are bridged; wherein B.sup.1 and
B.sup.2 are bridged, then: [0042] M, N, A.sup.1, B.sup.1, B.sup.2,
A.sup.2 and N form a 7 to 10 member ring according to Formula
Ib;
##STR00012##
[0042] or [0043] N, A.sup.1, B.sup.1, B.sup.2 and A.sup.2 form a 5
to 10 member ring according to Formula Ic,
##STR00013##
[0043] or [0044] N, A.sup.1, B.sup.1, B.sup.2 and A.sup.2 form a
first 5 to 10 member ring and B.sup.1 and B.sup.2 form a second 5
to 20 member ring according to Formula Id:
##STR00014##
[0044] wherein the hole injection layer contains the charge neutral
metal amide compound in the range of about .gtoreq.50 wt.-% to
about .ltoreq.100 wt.-%, preferably about .gtoreq.60 wt.-% to about
.ltoreq.100 wt.-%, further preferred about .gtoreq.70 wt.-% to
about .ltoreq.100 wt.-%, in addition preferred about .gtoreq.80
wt.-% to about .ltoreq.100 wt.-%, or about .gtoreq.95 wt.-% to
about .ltoreq.100 wt.-%, or about .gtoreq.98 wt.-% to about
.ltoreq.100 wt.-%.
[0045] According to another aspect of the present invention, there
is provided a hole injection layer for an OLED comprising a charge
neutral metal amide compound according to Formula Ia, wherein the
hole injection layer contains the charge neutral metal amide
compound in the range of about .gtoreq.95 wt.-% to about
.ltoreq.100 wt.-%.
[0046] According to another aspect of the present invention, there
is provided a hole injection layer for an OLED comprising a charge
neutral metal amide compound according to Formula Ia, wherein the
hole injection layer contains the charge neutral metal amide
compound in the range of about .gtoreq.98 wt.-% to about
.ltoreq.100 wt.-%.
[0047] According to another aspect of the present invention, there
is provided a hole injection layer for an OLED comprising a charge
neutral metal amide compound according to Formula Ib, Ic and/or Ic,
wherein the hole injection layer contains the charge neutral metal
amide compound in the range of about .gtoreq.98 wt.-% to about
.ltoreq.100 wt.-%.
[0048] According to another aspect of the present invention, there
is provided a hole injection layer for an OLED comprising at least
one charge neutral metal amide compound according to Formula C1 to
C25, D1 to D24 and/or F1 to F46, wherein the hole injection layer
contains the charge neutral metal amide compound in the range of
about .gtoreq.50 wt.-% to about .ltoreq.100 wt.-%, preferably about
.gtoreq.60 wt.-% to about .ltoreq.100 wt.-%, further preferred
about .gtoreq.70 wt.-% to about .ltoreq.100 wt.-%, in addition
preferred about .gtoreq.80 wt.-% to about .ltoreq.100 wt.-%, or
about .gtoreq.95 wt.-% to about .ltoreq.100 wt.-%, or about
.gtoreq.98 wt.-% to about .ltoreq.100 wt.-%.
[0049] According to another aspect of the present invention, there
is provided a hole injection layer for an OLED comprising at least
one charge neutral metal amide compound according to Formula C1,
wherein the hole injection layer contains the charge neutral metal
amide compound in the range of about .gtoreq.50 wt.-% to about
.ltoreq.100 wt.-%, preferably about .gtoreq.60 wt.-% to about
.ltoreq.100 wt.-%, further preferred about .gtoreq.70 wt.-% to
about .ltoreq.100 wt.-%, in addition preferred about .gtoreq.80
wt.-% to about .ltoreq.100 wt.-%, or about .gtoreq.95 wt.-% to
about .ltoreq.100 wt.-%, or about .gtoreq.98 wt.-% to about
.ltoreq.100 wt.-%.
[0050] It has been surprisingly found that a metal amide layer
(HIL) inserted between the anode and the hole transport layer
effectively promotes hole injection into the hole transport layer.
For example, if the HOMO level of the hole transport layer is
further away from vacuum level, the performance of metal amides is
superior to CNHAT, in particular the voltage. Furthermore,
effective hole injection even into very deep HOMO HTLs (HOMO
further away from vacuum level) can be achieved. This cannot be
achieved with prior art materials, such as CNHAT, which is
typically used as a HIL material. Efficient hole injection into
very deep HOMO levels enables the use of high efficiency emission
layers, in particular phosphorescent blue and green emitters and
emission which relies on TADF (thermally activated delayed
fluorescence).
[0051] The organic light-emitting diode (OLED) can be a bottom
emission OLED or a top emission OLED.
[0052] For the following defined terms, these definitions shall be
applied, unless a different definition is given in the claims or
elsewhere in this specification.
[0053] The bond between N and the metal M, as indicated for example
in Formula 1a, 1b, 1c, and 1d, can be a covalent bond or N forms a
non-covalent interaction to the metal M. Without being bond to a
specific theory it is assumed by the inventors that this kind of
compounds may form a covalent bond between N and M or N forms a
non-covalent interaction to the metal M, as can be seen from the
example below:
##STR00015##
[0054] The dotted line and/or an arrow symbolizes a non-covalent
interaction. A non-covalent interaction differs from a covalent
bond in that it does not involve the sharing of electrons, but
rather involves more dispersed variations of electromagnetic
interactions between molecules or within a molecule. Non-covalent
interactions can be generally classified into four categories,
electrostatic, .pi.-effects, van der Waals forces, and hydrophobic
effects.
[0055] The voltage, also named U, is measured in Volt (V) at 10
milliAmpere per square centimeter (mA/cm.sup.2) in bottom emission
devices and at 15 mA/cm.sup.2 in top emission devices.
[0056] The voltage stability over time U(50 h)-U(0 h) is measured
in Volt (V) at 15 mA/cm.sup.2. To calculate the voltage stability
over time, the voltage at the start of the stability test (U(0 h))
is subtracted from the voltage after 50 hours (h) (U(50 h)). The
smaller the value U(50 h)-U(0 h) is the better is the voltage
stability over time.
[0057] The external quantum efficiency, also named EQE, is measured
in percent (%). The color space is described by coordinates CIE-x
and CIE-y (International Commission on Illumination 1931). For blue
emission the CIE-y is of particular importance. A smaller CIE-y
denotes a deeper blue color.
[0058] The highest occupied molecular orbital, also named HOMO, and
lowest unoccupied molecular orbital, also named LUMO, are measured
in electron volt (eV).
[0059] The term "OLED" and "organic light-emitting diode" is
simultaneously used and having the same meaning.
[0060] The term "transition metal" means and includes any element
in the d-block of the periodic table, which includes groups 3 to 12
elements on the periodic table.
[0061] As used herein, "weight percent", "wt.-%", "percent by
weight", "by weight", and variations thereof refer to a
composition, component, substance or agent as the weight of that
composition, component, substance or agent of the respective
electron transport layer divided by the total weight of the
composition thereof and multiplied by 100. It is understood that
the total weight percent amount of all components, substances or
agents of the respective electron transport layer are selected such
that it does not exceed 100 wt.-%.
[0062] All numeric values are herein assumed to be modified by the
term "about", whether or not explicitly indicated. As used herein,
the term "about" refers to variation in the numerical quantity that
can occur. Whether or not, modified by the term "about", the claims
include equivalents to the quantities.
[0063] It should be noted that, as used in this specification and
the appended claims, the singular forms "a", "an", and "the"
include plural referents unless the content clearly dictates
otherwise.
[0064] The term "free of", "does not contain", "does not comprise"
does not exclude impurities. Impurities have no technical effect
with respect to the object achieved by the present invention.
[0065] The term "alkyl" refers to straight-chain or branched alkyl
groups.
[0066] The term "1 to 20 carbon atoms" as used herein refers to
straight-chain or branched alkyl groups having 1 to 20 carbon
atoms. The alkyl groups can be selected from the group comprising
methyl, ethyl and the isomers of propyl, butyl or pentyl, such as
isopropyl, isobutyl, tert.-butyl, sec.-butyl and/or isopentyl. The
term "aryl" refers to aromatic groups for example phenyl or
naphthyl.
[0067] Herein, when a first element is referred to as being formed
or disposed "on" a second element, the first element can be
disposed directly on the second element or one or more other
elements may be disposed there between. When a first element is
referred to as being formed or disposed "directly on" a second
element, no other elements are disposed there between.
[0068] According to another aspect, there is provided a hole
injection layer for an OLED comprising a charge neutral metal amide
compound, wherein the charge neutral metal amide compound has the
Formula Ia:
##STR00016##
wherein: [0069] G=halide, O, alkoxylate or amine of Formula IIa to
IIe:
[0069] ##STR00017## [0070] R.sup.1 to R.sup.5 are independently
selected from the group comprising H, C.sub.1 to C.sub.20 alkyl,
C.sub.1 to C.sub.20 heteroalkyl, unsubstituted or C.sub.1 to
C.sub.12 substituted C.sub.6 to C.sub.20 aryl, unsubstituted or
C.sub.1 to C.sub.12 substituted heteroaryl with 5 to 20
ring-forming atoms, halogenated or perhalogenated C.sub.1 to
C.sub.20 alkyl, halogenated or perhalogenated C.sub.1 to C.sub.20
heteroalkyl, halogenated or perhalogenated C.sub.6 to C.sub.20
aryl, halogenated or perhalogenated heteroaryl with 5 to 20
ring-forming atoms; or [0071] at least one R.sup.1 and R.sup.4
and/or R.sup.2 and R.sup.3 and/or R.sup.1 and R.sup.5 are bridged
and form a 5 to 20 member ring; [0072] m=0, 1, 2, 3 or 4; [0073]
M=a metal selected from the group comprising alkali metal, alkaline
earth metal, Al, Ga, In, transition metal or rare earth metal;
[0074] wherein the bond between N and the metal M is a covalent
bond or N forms a non-covalent interaction to the metal M; [0075]
L=charge neutral ligand which coordinates to the metal M, selected
from the group comprising H.sub.2O, C.sub.2 to C.sub.40 mono- or
multi-dentate ethers and C.sub.2 to C.sub.40 thioethers, C.sub.2 to
C.sub.40 amines, C.sub.2 to C.sub.40 phosphine, C.sub.2 to C.sub.20
alkyl nitrile or C.sub.2 to C.sub.40 aryl nitrile, or a compound
according to Formula (III);
[0075] ##STR00018## [0076] wherein R.sup.6 and R.sup.7 are
independently selected from C.sub.1 to C.sub.20 alkyl, C.sub.1 to
C.sub.20 heteroalkyl, C.sub.6 to C.sub.20 aryl, heteroaryl with 5
to 20 ring-forming atoms, halogenated or perhalogenated C.sub.1 to
C.sub.20 alkyl, halogenated or perhalogenated C.sub.1 to C.sub.20
heteroalkyl, halogenated or perhalogenated C.sub.6 to C.sub.20
aryl, halogenated or perhalogenated heteroaryl with 5 to 20
ring-forming atoms, or at least one R.sup.6 and R.sup.7 are bridged
and form a 5 to 20 member ring, or the two R.sup.6 and/or the two
R.sup.7 are bridged and form a 5 to 40 member ring or form a 5 to
40 member ring comprising an unsubstituted or C.sub.1 to C.sub.12
substituted phenanthroline; [0077] p=0, 1, 2 or 3; [0078] A.sup.1,
A.sup.2, A.sup.3 and A.sup.4 are independently selected from CO,
SO.sub.2 or POR.sup.8; [0079] R.sup.8=electron withdrawing group
selected from the group comprising halide, nitrile, halogenated or
perhalogenated C.sub.1 to C.sub.20 alkyl, halogenated or
perhalogenated C.sub.6 to C.sub.20 aryl, or halogenated or
perhalogenated heteroaryl with 5 to 20 ring-forming atoms; [0080]
n=1, 2, 3, 4 or 5; [0081] B.sup.1, B.sup.2, B.sup.3 and B.sup.4 are
same or independently selected from substituted or unsubstituted
C.sub.1 to C.sub.20 alkyl, substituted or unsubstituted C.sub.1 to
C.sub.20 heteroalkyl, substituted or unsubstituted C.sub.6 to
C.sub.20 aryl, substituted or unsubstituted C.sub.5 to C.sub.20
heteroaryl.
[0082] According to another aspect there is provided a hole
injection layer for an OLED comprising a charge neutral metal amide
compound, wherein the charge neutral metal amide compound has the
Formula Ib, Ic or Id:
wherein: [0083] B.sup.1 and B.sup.2 are bridged; [0084] B.sup.3 and
B.sup.4 are same or independently selected from substituted or
unsubstituted C.sub.1 to C.sub.20 alkyl, substituted or
unsubstituted C.sub.1 to C.sub.20 heteroalkyl, substituted or
unsubstituted C.sub.6 to C.sub.20 aryl, substituted or
unsubstituted C.sub.5 to C.sub.20 heteroaryl; [0085] M, N, A.sup.1,
B.sup.1, B.sup.2, A.sup.2 and N form a 7 to 10 member ring
according to Formula Ib;
##STR00019##
[0085] or [0086] N, A.sup.1, B.sup.1, B.sup.2 and A.sup.2 form a 5
to 10 member ring according to Formula Ic,
##STR00020##
[0086] or [0087] N, A.sup.1, B.sup.1, B.sup.2 and A.sup.2 form a
first 5 to 10 member ring and B.sup.1 and B.sup.2 form a second 5
to 20 member ring according to Formula Id:
##STR00021##
[0087] wherein: [0088] G=halide, O, alkoxylate or amine of Formula
IIa to IIe:
[0088] ##STR00022## [0089] R.sup.1 to R.sup.5 are independently
selected from the group comprising H, C.sub.1 to C.sub.20 alkyl,
C.sub.1 to C.sub.20 heteroalkyl, unsubstituted or C.sub.1 to
C.sub.12 substituted C.sub.6 to C.sub.20 aryl, unsubstituted or
C.sub.1 to C.sub.12 substituted heteroaryl with 5 to 20
ring-forming atoms, halogenated or perhalogenated C.sub.1 to
C.sub.20 alkyl, halogenated or perhalogenated C.sub.1 to C.sub.20
heteroalkyl, halogenated or perhalogenated C.sub.6 to C.sub.20
aryl, halogenated or perhalogenated heteroaryl with 5 to 20
ring-forming atoms; or [0090] at least one R.sup.1 and R.sup.4
and/or R.sup.2 and R.sup.3 and/or R.sup.1 and R.sup.5 are bridged
and form a 5 to 20 member ring; [0091] m=0, 1, 2, 3 or 4; [0092]
M=a metal selected from the group comprising alkali metal, alkaline
earth metal, Al, Ga, In, transition metal or rare earth metal;
wherein the bond between N and the metal M is a covalent bond or N
forms a non-covalent interaction to the metal M; [0093] L=charge
neutral ligand which coordinates to the metal M, selected from the
group comprising H.sub.2O, C.sub.2 to C.sub.40 mono- or
multi-dentate ethers and C.sub.2 to C.sub.40 thioethers, C.sub.2 to
C.sub.40 amines, C.sub.2 to C.sub.40 phosphine, C.sub.2 to C.sub.20
alkyl nitrile or C.sub.2 to C.sub.40 aryl nitrile, or a compound
according to Formula (III);
[0093] ##STR00023## [0094] wherein R.sup.6 and R.sup.7 are
independently selected from C.sub.1 to C.sub.20 alkyl, C.sub.1 to
C.sub.20 heteroalkyl, C.sub.6 to C.sub.20 aryl, heteroaryl with 5
to 20 ring-forming atoms, halogenated or perhalogenated C.sub.1 to
C.sub.20 alkyl, halogenated or perhalogenated C.sub.1 to C.sub.20
heteroalkyl, halogenated or perhalogenated C.sub.6 to C.sub.20
aryl, halogenated or perhalogenated heteroaryl with 5 to 20
ring-forming atoms, or at least one R.sup.6 and R.sup.7 are bridged
and form a 5 to 20 member ring, or the two R.sup.6 and/or the two
R.sup.7 are bridged and form a 5 to 40 member ring or form a 5 to
40 member ring comprising an unsubstituted or C.sub.1 to C.sub.12
substituted phenanthroline; [0095] p=0, 1, 2 or 3; [0096] A.sup.1,
A.sup.2, A.sup.3 and A.sup.4 are independently selected from CO,
SO.sub.2 or POR.sup.8; [0097] R.sup.8=electron withdrawing group
selected from the group comprising halide, nitrile, halogenated or
perhalogenated C.sub.1 to C.sub.20 alkyl, halogenated or
perhalogenated C.sub.6 to C.sub.20 aryl, or halogenated or
perhalogenated heteroaryl with 5 to 20 ring-forming atoms; [0098]
n=1, 2, 3, 4 or 5.
[0099] According to another aspect there is provided a hole
injection layer for an OLED comprising a charge neutral metal amide
compound, wherein the charge neutral metal amide compound has the
Formula Ib:
##STR00024##
wherein: [0100] B.sup.1 and B.sup.2 are bridged; [0101] M, N,
A.sup.1, B.sup.1, B.sup.2, A.sup.2 and N form a 7 to 10 member ring
according to Formula Ib;
##STR00025##
[0101] wherein: [0102] G=halide, O, alkoxylate or amine of Formula
IIa to IIe:
[0102] ##STR00026## [0103] R.sup.1 to R.sup.5 are independently
selected from the group comprising H, C.sub.1 to C.sub.20 alkyl,
C.sub.1 to C.sub.20 heteroalkyl, unsubstituted or C.sub.1 to
C.sub.12 substituted C.sub.6 to C.sub.20 aryl, unsubstituted or
C.sub.1 to C.sub.12 substituted heteroaryl with 5 to 20
ring-forming atoms, halogenated or perhalogenated C.sub.1 to
C.sub.20 alkyl, halogenated or perhalogenated C.sub.1 to C.sub.20
heteroalkyl, halogenated or perhalogenated C.sub.6 to C.sub.20
aryl, halogenated or perhalogenated heteroaryl with 5 to 20
ring-forming atoms; or [0104] at least one R.sup.1 and R.sup.4
and/or R.sup.2 and R.sup.3 and/or R.sup.1 and R.sup.5 are bridged
and form a 5 to 20 member ring; [0105] m=0, 1, 2, 3 or 4; [0106]
M=a metal selected from the group comprising alkali metal, alkaline
earth metal, Al, Ga, In, transition metal or rare earth metal;
[0107] wherein the bond between N and the metal M is a covalent
bond or N forms a non-covalent interaction to the metal M; [0108]
L=charge neutral ligand which coordinates to the metal M, selected
from the group comprising H.sub.2O, C.sub.2 to C.sub.40 mono- or
multi-dentate ethers and C.sub.2 to C.sub.40 thioethers, C.sub.2 to
C.sub.40 amines, C.sub.2 to C.sub.40 phosphine, C.sub.2 to C.sub.20
alkyl nitrile or C.sub.2 to C.sub.40 aryl nitrile, or a compound
according to Formula (III);
[0108] ##STR00027## [0109] wherein R.sup.6 and R.sup.7 are
independently selected from C.sub.1 to C.sub.20 alkyl, C.sub.1 to
C.sub.20 heteroalkyl, C.sub.6 to C.sub.20 aryl, heteroaryl with 5
to 20 ring-forming atoms, halogenated or perhalogenated C.sub.1 to
C.sub.20 alkyl, halogenated or perhalogenated C.sub.1 to C.sub.20
heteroalkyl, halogenated or perhalogenated C.sub.6 to C.sub.20
aryl, halogenated or perhalogenated heteroaryl with 5 to 20
ring-forming atoms, or at least one R.sup.6 and R.sup.7 are bridged
and form a 5 to 20 member ring, or the two R.sup.6 and/or the two
R.sup.7 are bridged and form a 5 to 40 member ring or form a 5 to
40 member ring comprising an unsubstituted or C.sub.1 to C.sub.12
substituted phenanthroline; [0110] p=0, 1, 2 or 3; [0111] A.sup.1
and A.sup.2 are independently selected from CO, SO.sub.2 or
POR.sup.8; [0112] R.sup.8=electron withdrawing group selected from
the group comprising halide, nitrile, halogenated or perhalogenated
C.sub.1 to C.sub.20 alkyl, halogenated or perhalogenated C.sub.6 to
C.sub.20 aryl, or halogenated or perhalogenated heteroaryl with 5
to 20 ring-forming atoms; [0113] n=1, 2, 3, 4 or 5.
[0114] According to another aspect for the charge neutral metal
amide compound according to the invention B.sup.1, B.sup.2, B.sup.3
and B.sup.4 can be independently selected from a substituted
C.sub.1 to C.sub.20 alkyl, substituted C.sub.1 to C.sub.20
heteroalkyl, substituted C.sub.6 to C.sub.20 aryl, or substituted
C.sub.5 to C.sub.20 heteroaryl; wherein the substituent of the
substituted C.sub.1 to C.sub.20 alkyl, substituted C.sub.1 to
C.sub.20 heteroalkyl, substituted C.sub.6 to C.sub.20 aryl, or
substituted C.sub.5 to C.sub.20 heteroaryl; [0115] wherein the
substituent can be an electron withdrawing group selected from the
group comprising a halide, nitrile, perhalogenated C.sub.1 to
C.sub.20 alkyl, perhalogenated C.sub.6 to C.sub.20 aryl,
perhalogenated heteroaryl with 6 to 20 ring-forming atoms,
preferably the electron withdrawing group is a fluoride,
perfluroinated C.sub.1 to C.sub.20 alkyl, perfluorinated C.sub.6 to
C.sub.20 aryl, or perfluorinated heteroaryl with 5 to 20
ring-forming atoms.
[0116] In order to increase the vacuum vaporization it can be
preferred that according to one embodiment the substituent can be a
C.sub.1 to C.sub.6 alkyl or C.sub.1 to C.sub.6 heteroalkyl, and
more preferred an C.sub.1 to C.sub.4 alkyl or C.sub.1 to C.sub.4
heteroalkyl.
[0117] In order to improve the solution processing it can be
preferred that according to one embodiment the substituent can be a
C.sub.4 to C.sub.20 alkyl or C.sub.4 to C.sub.20 heteroalkyl, and
more preferred an C.sub.6 to C.sub.18 alkyl or C.sub.6 to C.sub.18
heteroalkyl.
[0118] According to another aspect there is provided a hole
injection layer for an OLED comprising a charge neutral metal amide
compound, wherein the charge neutral metal amide compound has the
Formula Ic:
##STR00028##
wherein: [0119] B.sup.1 and B.sup.2 are bridged; [0120] N, A.sup.1,
B.sup.1, B.sup.2 and A.sup.2 form a 5 to 10 member ring according
to Formula Ic,
##STR00029##
[0120] wherein: [0121] G=halide, O, alkoxylate or amine of Formula
Ia to lie:
[0121] ##STR00030## [0122] R.sup.1 to R.sup.5 are independently
selected from the group comprising H, C.sub.1 to C.sub.20 alkyl,
C.sub.1 to C.sub.20 heteroalkyl, unsubstituted or C.sub.1 to
C.sub.12 substituted C.sub.6 to C.sub.20 aryl, unsubstituted or
C.sub.1 to C.sub.12 substituted heteroaryl with 5 to 20
ring-forming atoms, halogenated or perhalogenated C.sub.1 to
C.sub.20 alkyl, halogenated or perhalogenated C.sub.1 to C.sub.20
heteroalkyl, halogenated or perhalogenated C.sub.6 to C.sub.20
aryl, halogenated or perhalogenated heteroaryl with 5 to 20
ring-forming atoms; or [0123] at least one R.sup.1 and R.sup.4
and/or R.sup.2 and R.sup.3 and/or R.sup.1 and R.sup.5 are bridged
and form a 5 to 20 member ring; [0124] m=0, 1, 2, 3 or 4; [0125]
M=a metal selected from the group comprising alkali metal, alkaline
earth metal, Al, Ga, In, transition metal or rare earth metal;
wherein the bond between N and the metal M is a covalent bond or N
forms a non-covalent interaction to the metal M; [0126] L=charge
neutral ligand which coordinates to the metal M, selected from the
group comprising H.sub.2O, C.sub.2 to C.sub.40 mono- or
multi-dentate ethers and C.sub.2 to C.sub.40 thioethers, C.sub.2 to
C.sub.40 amines, C.sub.2 to C.sub.40 phosphine, C.sub.2 to C.sub.20
alkyl nitrile or C.sub.2 to C.sub.40 aryl nitrile, or a compound
according to Formula (III);
[0126] ##STR00031## [0127] wherein R.sup.6 and R.sup.7 are
independently selected from C.sub.1 to C.sub.20 alkyl, C.sub.1 to
C.sub.20 heteroalkyl, C.sub.6 to C.sub.20 aryl, heteroaryl with 5
to 20 ring-forming atoms, halogenated or perhalogenated C.sub.1 to
C.sub.20 alkyl, halogenated or perhalogenated C.sub.1 to C.sub.20
heteroalkyl, halogenated or perhalogenated C.sub.6 to C.sub.20
aryl, halogenated or perhalogenated heteroaryl with 5 to 20
ring-forming atoms, or at least one R.sup.6 and R.sup.7 are bridged
and form a 5 to 20 member ring, or the two R.sup.6 and/or the two
R.sup.7 are bridged and form a 5 to 40 member ring or form a 5 to
40 member ring comprising an unsubstituted or C.sub.1 to C.sub.12
substituted phenanthroline; [0128] p=0, 1, 2 or 3; [0129] A.sup.1
and A.sup.2 are independently selected from CO, SO.sub.2 or
POR.sup.8; [0130] R.sup.8=electron withdrawing group selected from
the group comprising halide, nitrile, halogenated or perhalogenated
C.sub.1 to C.sub.20 alkyl, halogenated or perhalogenated C.sub.6 to
C.sub.20 aryl, or halogenated or perhalogenated heteroaryl with 5
to 20 ring-forming atoms; [0131] n=1, 2, 3, 4 or 5.
[0132] According to another aspect there is provided a hole
injection layer for an OLED comprising a charge neutral metal amide
compound, wherein the charge neutral metal amide compound has the
Formula Id:
##STR00032##
wherein: [0133] B.sup.1 and B.sup.2 are bridged; [0134] N, A.sup.1,
B.sup.1, B.sup.2 and A.sup.2 form a first 5 to 10 member ring and
B.sup.1 and B.sup.2 form a second 5 to 20 member ring according to
Formula Id:
##STR00033##
[0134] wherein: [0135] G=halide, O, alkoxylate or amine of Formula
IIa to IIe:
[0135] ##STR00034## [0136] R.sup.1 to R.sup.5 are independently
selected from the group comprising H, C.sub.1 to C.sub.20 alkyl,
C.sub.1 to C.sub.20 heteroalkyl, unsubstituted or C.sub.1 to
C.sub.12 substituted C.sub.6 to C.sub.20 aryl, unsubstituted or
C.sub.1 to C.sub.12 substituted heteroaryl with 5 to 20
ring-forming atoms, halogenated or perhalogenated C.sub.1 to
C.sub.20 alkyl, halogenated or perhalogenated C.sub.1 to C.sub.20
heteroalkyl, halogenated or perhalogenated C.sub.6 to C.sub.20
aryl, halogenated or perhalogenated heteroaryl with 5 to 20
ring-forming atoms; or [0137] at least one R.sup.1 and R.sup.4
and/or R.sup.2 and R.sup.3 and/or R.sup.1 and R.sup.5 are bridged
and form a 5 to 20 member ring; [0138] m=0, 1, 2, 3 or 4; [0139]
M=a metal selected from the group comprising alkali metal, alkaline
earth metal, Al, Ga, In, transition metal or rare earth metal;
[0140] wherein the bond between N and the metal M is a covalent
bond or N forms a non-covalent interaction to the metal M; [0141]
L=charge neutral ligand which coordinates to the metal M, selected
from the group comprising H.sub.2O, C.sub.2 to C.sub.40 mono- or
multi-dentate ethers and C.sub.2 to C.sub.40 thioethers, C.sub.2 to
C.sub.40 amines, C.sub.2 to C.sub.40 phosphine, C.sub.2 to C.sub.20
alkyl nitrile or C.sub.2 to C.sub.40 aryl nitrile, or a compound
according to Formula (III);
[0141] ##STR00035## [0142] wherein R.sup.6 and R.sup.7 are
independently selected from C.sub.1 to C.sub.20 alkyl, C.sub.1 to
C.sub.20 heteroalkyl, C.sub.6 to C.sub.20 aryl, heteroaryl with 5
to 20 ring-forming atoms, halogenated or perhalogenated C.sub.1 to
C.sub.20 alkyl, halogenated or perhalogenated C.sub.1 to C.sub.20
heteroalkyl, halogenated or perhalogenated C.sub.6 to C.sub.20
aryl, halogenated or perhalogenated heteroaryl with 5 to 20
ring-forming atoms, or at least one R.sup.6 and R.sup.7 are bridged
and form a 5 to 20 member ring, or the two R.sup.6 and/or the two
R.sup.7 are bridged and form a 5 to 40 member ring or form a 5 to
40 member ring comprising an unsubstituted or C.sub.1 to C.sub.12
substituted phenanthroline; [0143] p=0, 1, 2 or 3; [0144] A.sup.1
and A.sup.2 are independently selected from CO, SO.sub.2 or
POR.sup.8; [0145] R.sup.8=electron withdrawing group selected from
the group comprising halide, nitrile, halogenated or perhalogenated
C.sub.1 to C.sub.20 alkyl, halogenated or perhalogenated C.sub.6 to
C.sub.20 aryl, or halogenated or perhalogenated heteroaryl with 5
to 20 ring-forming atoms; [0146] n=1, 2, 3, 4 or 5.
[0147] According to one aspect, the hole injection layer (HIL) may
comprises the charge neutral metal amide compound according to
formula Ia to Id in the range of about .gtoreq.50 wt.-% to about
.ltoreq.100 wt.-%, preferably about .gtoreq.60 wt.-% to about
.ltoreq.100 wt.-%, further preferred about .gtoreq.70 wt.-% to
about .ltoreq.100 wt.-%, in addition preferred about .gtoreq.80
wt.-% to about .ltoreq.100 wt.-%, or about .gtoreq.95 wt.-% to
about .ltoreq.100 wt.-%, or about .gtoreq.98 wt.-% to about
.ltoreq.100 wt.-%, or about .gtoreq.99 wt.-% to about .ltoreq.100
wt.-%, and more preferred about .gtoreq.90 wt.-% to about
.ltoreq.100 wt.-% or about .gtoreq.95 wt.-% to about .ltoreq.99
wt.-%.
[0148] According to another aspect, the hole injection layer (HIL)
may comprises the charge neutral metal amide compound according to
formula Ia to Id in the range of about .gtoreq.60 wt.-% to about
.ltoreq.100 wt.-%, further preferred about .gtoreq.70 wt.-% to
about .ltoreq.100 wt.-%, in addition preferred about .gtoreq.80
wt.-% to about .ltoreq.100 wt.-%, or about .gtoreq.95 wt.-% to
about .ltoreq.100 wt.-%, or about .gtoreq.98 wt.-% to about
.ltoreq.100 wt.-%, or about .gtoreq.99 wt.-% to about .ltoreq.100
wt.-%, and more preferred about .gtoreq.90 wt.-% to about
.ltoreq.100 wt.-% or about .gtoreq.95 wt.-% to about .ltoreq.99
wt.-%.
[0149] According to another aspect, the hole injection layer (HIL)
may comprises the charge neutral metal amide compound according to
formula Ia to Id in the range of about .gtoreq.70 wt.-% to about
.ltoreq.100 wt.-%, in addition preferred about .gtoreq.80 wt.-% to
about .ltoreq.100 wt.-%, or about .gtoreq.95 wt.-% to about
.ltoreq.100 wt.-%, or about .gtoreq.98 wt.-% to about .ltoreq.100
wt.-%, or about .gtoreq.99 wt.-% to about .ltoreq.100 wt.-%, and
more preferred about .gtoreq.90 wt.-% to about .ltoreq.100 wt.-% or
about .gtoreq.95 wt.-% to about .ltoreq.99 wt.-%.
[0150] According to another aspect, the hole injection layer (HIL)
may comprises the charge neutral metal amide compound according to
formula Ia to Id in the range of about .gtoreq.80 wt.-% to about
.ltoreq.100 wt.-%, or about .gtoreq.95 wt.-% to about .ltoreq.100
wt.-%, or about .gtoreq.98 wt.-% to about .ltoreq.100 wt.-%, or
about .gtoreq.99 wt.-% to about .ltoreq.100 wt.-%, and more
preferred about .gtoreq.90 wt.-% to about .ltoreq.100 wt.-% or
about .gtoreq.95 wt.-% to about .ltoreq.99 wt.-%.
[0151] According to another aspect, the hole injection layer (HIL)
may comprises the charge neutral metal amide compound according to
formula Ia to Id in the range of about .gtoreq.95 wt.-% to about
.ltoreq.100 wt.-%, or about .gtoreq.98 wt.-% to about .ltoreq.100
wt.-%, or about .gtoreq.99 wt.-% to about .ltoreq.100 wt.-%, and
more preferred about .gtoreq.90 wt.-% to about .ltoreq.100 wt.-% or
about .gtoreq.95 wt.-% to about .ltoreq.99 wt.-%.
[0152] According to another aspect, the hole injection layer (HIL)
may comprises the charge neutral metal amide compound according to
formula Ia to Id in the range of about .gtoreq.98 wt.-% to about
.ltoreq.100 wt.-%, or about .gtoreq.99 wt.-% to about .ltoreq.100
wt.-%, and more preferred about .gtoreq.90 wt.-% to about
.ltoreq.100 wt.-% or about .gtoreq.95 wt.-% to about .ltoreq.99
wt.-%.
[0153] According to another aspect, the hole injection layer (HIL)
may comprises the charge neutral metal amide compound according to
formula Ia to Id in the range of about .gtoreq.99 wt.-% to about
.ltoreq.100 wt.-%, and more preferred about .gtoreq.90 wt.-% to
about .ltoreq.100 wt.-% or about .gtoreq.95 wt.-% to about
.ltoreq.99 wt.-%.
[0154] According to another aspect, the hole injection layer (HIL)
may consist of the charge neutral metal amide compound according to
Formula Ia to Id.
[0155] According to another aspect, the hole injection layer (HIL)
may comprises .gtoreq.0 wt.-% to .ltoreq.20 wt % of a HTL compound,
preferably .gtoreq.0.1 wt.-% to .ltoreq.15 wt.-% of a HTL compound,
and even more preferred .gtoreq.0.5 wt.-% to .ltoreq.10 wt.-% of a
HTL compound, and also preferred .ltoreq.2 wt.-%, wherein the HTL
compound differs from the HIL neutral metal amide compound
according to formula Ia to Id.
[0156] According to another aspect, the hole injection layer (HIL)
may comprises .gtoreq.0 wt.-% to .ltoreq.20 wt.-% of a HTL
compound, preferably .gtoreq.0.1 wt.-% to .ltoreq.15 wt.-% of a HTL
compound, and even more preferred .gtoreq.0.5 wt.-% to .ltoreq.10
wt.-% of a HTL compound.
[0157] According to an aspect of the present invention, there is
provided a hole injection layer for an OLED comprising a charge
neutral metal amide compound, wherein the charge neutral metal
amide compound has the Formula Ia:
##STR00036##
wherein: [0158] G=halide, O, alkoxylate or amine of Formula IIa to
IIe:
[0158] ##STR00037## [0159] R.sup.1 to R.sup.5 are independently
selected from the group comprising H, C.sub.1 to C.sub.20 alkyl,
C.sub.1 to C.sub.20 heteroalkyl, unsubstituted or C.sub.1 to
C.sub.12 substituted C.sub.6 to C.sub.20 aryl, unsubstituted or
C.sub.1 to C.sub.12 substituted heteroaryl with 5 to 20
ring-forming atoms, halogenated or perhalogenated C.sub.1 to
C.sub.20 alkyl, halogenated or perhalogenated C.sub.1 to C.sub.20
heteroalkyl, halogenated or perhalogenated C.sub.6 to C.sub.20
aryl, halogenated or perhalogenated heteroaryl with 5 to 20
ring-forming atoms; or [0160] at least one R.sup.1 and R.sup.4
and/or R.sup.2 and R.sup.3 and/or R.sup.1 and R.sup.5 are bridged
and form a 5 to 20 member ring; [0161] m=0, 1, 2, 3 or 4; [0162]
M=a metal selected from the group comprising alkali metal, alkaline
earth metal, Al, Ga, In, transition metal or rare earth metal;
[0163] wherein the bond between N and the metal M is a covalent
bond or N forms a non-covalent interaction to the metal M; [0164]
L=charge neutral ligand which coordinates to the metal M, selected
from the group comprising H.sub.2O, C.sub.2 to C.sub.40 mono- or
multi-dentate ethers and C.sub.2 to C.sub.40 thioethers, C.sub.2 to
C.sub.40 amines, C.sub.2 to C.sub.40 phosphine, C.sub.2 to C.sub.20
alkyl nitrile or C.sub.2 to C.sub.40 aryl nitrile, or a compound
according to Formula (III);
[0164] ##STR00038## [0165] wherein R.sup.6 and R.sup.7 are
independently selected from C.sub.1 to C.sub.20 alkyl, C.sub.1 to
C.sub.20 heteroalkyl, C.sub.6 to C.sub.20 aryl, heteroaryl with 5
to 20 ring-forming atoms, halogenated or perhalogenated C.sub.1 to
C.sub.20 alkyl, halogenated or perhalogenated C.sub.1 to C.sub.20
heteroalkyl, halogenated or perhalogenated C.sub.6 to C.sub.20
aryl, halogenated or perhalogenated heteroaryl with 5 to 20
ring-forming atoms, or at least one R.sup.6 and R.sup.7 are bridged
and form a 5 to 20 member ring, or the two R.sup.6 and/or the two
R.sup.7 are bridged and form a 5 to 40 member ring or form a 5 to
40 member ring comprising an unsubstituted or C.sub.1 to C.sub.12
substituted phenanthroline; [0166] p=0, 1, 2 or 3; [0167] A.sup.1,
A.sup.2, A.sup.3 and A.sup.4 are independently selected from CO,
SO.sub.2 or POR.sup.8; [0168] R.sup.8=electron withdrawing group
selected from the group comprising halide, nitrile, halogenated or
perhalogenated C.sub.1 to C.sub.20 alkyl, halogenated or
perhalogenated C.sub.6 to C.sub.20 aryl, or halogenated or
perhalogenated heteroaryl with 5 to 20 ring-forming atoms; [0169]
n=1, 2, 3, 4 or 5; [0170] B.sup.3 and B.sup.4 are same or
independently selected from substituted or unsubstituted C.sub.1 to
C.sub.20 alkyl, substituted or unsubstituted C.sub.1 to C.sub.20
heteroalkyl, substituted or unsubstituted C.sub.6 to C.sub.20 aryl,
substituted or unsubstituted C.sub.5 to C.sub.20 heteroaryl; [0171]
B.sup.1 and B.sup.2 are bridged, wherein: [0172] M, N, A.sup.1,
B.sup.1, B.sup.2, A.sup.2 and N form a 7 to 10 member ring
according to Formula Ib;
##STR00039##
[0172] or [0173] N, A.sup.1, B.sup.1, B.sup.2 and A.sup.2 form a 5
to 10 member ring according to Formula Ic,
##STR00040##
[0173] or [0174] N, A.sup.1, B.sup.1, B.sup.2 and A.sup.2 form a
first 5 to 10 member ring and B.sup.1 and B.sup.2 form a second 5
to 20 member ring according to Formula Id:
##STR00041##
[0175] According to one aspect the charge neutral ligand L may be
selected from the group comprising C.sub.2 to C.sub.20 glycole
ethers, C.sub.2 to C.sub.20 ethylendiamine derivatives, and more
preferred bis(2-methoxyethyl) ether, tetrahydrofurane,
tetrahydrothiophen,
N.sup.1,N.sup.1,N.sup.2,N.sup.2-tetramethyl-1,2-ethanediamine,
N-((E,2E)-2-{[(E)-1,1-dimethylethyl]imino}ethylidene)-2-methyl-2-propanam-
ine, acetonitrile, trisphenylphosphine, trismethylphosphine,
tris(cylcohexyl)phosphine, 1,2-bis(diphenylphosphino)ethane,
bispyridine, phenanthroline,
(2E,3E)-N.sup.2,N.sup.3-diphenylbutane-2,3-diimine or
(1E,2E)-N.sup.1,N.sup.2, 1,2-tetraphenylethane-1,2-diimine.
[0176] According to one aspect of the charge neutral metal amide
compound "m" may be selected that m=0, 1 or 2.
[0177] According to one aspect of the charge neutral metal amide
compound "M" may be selected from Li(I), Na(I), K(I), Cs(I),
Mg(II), Ca(II), Sr(II), Ba(II), Sc(III), Y(III), Ti(IV), V(III-V),
Cr(III-VI), Mn(II), Mn(III), Fe(II), Fe(III), Co(II), Co(III),
Ni(II), Cu(I), Cu(II), Zn(II), Ag(I), Au(I), Au(III), Al(III),
Ga(III), In(III), Sn(II), Sn(IV), or Pb(II); preferably M is
selected from Li(I), Mg(II), Mn(II) or Ag(I); and more preferred M
is selected from Mg(II) and Li(I).
[0178] According to one aspect of the charge neutral metal amide
compound, wherein may be (G).sub.m for m=1, then G is Cl; or may be
(G).sub.m for m=2, then G is O.
[0179] According to one aspect of the charge neutral metal amide
compound, wherein may be (G).sub.m-M is Cl--Al, Cl--Mg, O=V or
O.sub.2U.
[0180] According to one aspect of the charge neutral metal amide
compound, wherein may be for n.gtoreq.2 then: [0181] N, A.sup.1,
B.sup.1, A.sup.2 and B.sup.2 form a 5 to 10 member ring; or [0182]
M, N, A.sup.1, B.sup.1, A.sup.2 and B.sup.2 form a 7 to 10 member
ring; or [0183] M, N, A.sup.1, B.sup.1, A.sup.2 and B.sup.2 form a
7 to 10 member ring and A.sup.3, B.sup.3, A.sup.4 and B.sup.4 form
a 5 to 10 member ring.
[0184] According to another aspect the charge neutral ligand L may
the Formula Ia,
##STR00042##
wherein: [0185] A.sup.1 and A.sup.2 are same or independently
selected from CO, POR.sup.8 and SO.sub.2, preferably A.sup.1 and
A.sup.2 are selected same from CO, POR.sup.8, SO.sub.2; or [0186]
A.sup.1 and A.sup.2 are independently selected from CO, POR.sup.8,
SO.sub.2, and [0187] N, A.sup.1, B.sup.1, A.sup.2 and B.sup.2 form
a 5 to 10 member ring.
[0188] According to another aspect the charge neutral metal amide
compound of the hole injection layer may be selected from at least
one compound according to Formula IIa, IIb, IIc, IId, Ile, IIf, IIg
and/or IIh,
wherein for: [0189] p=0, m=1, 2, 3 or 4 and n=1, 2, 3 or 4, the
charge neutral metal amide compound has the Formula IIa:
[0189] ##STR00043## [0190] p=1, 2 or 3, and n=1, 2, 3 or 4 and m=0,
the charge neutral metal amide compound has the Formula IIb:
##STR00044##
[0190] or [0191] p=1, 2 or 3, n=1, 2, 3 or 4, m=1, 2, 3 or 4 and N,
A, B.sup.1, B.sup.2 and A.sup.2 form a 5 to 10 member ring, the
charge neutral metal amide compound has the Formula IIc:
##STR00045##
[0191] or [0192] p=1, 2 or 3, n=1, 2, 3 or 4, m=1, 2, 3 or 4 and N,
A.sup.1, B.sup.1, B.sup.2 and A.sup.2 form a first 5 to 10 member
ring and B.sup.1 and B.sup.2 are bridged to form a second 5 to 20
member ring, the charge neutral metal amide compound has the
Formula IId:
##STR00046##
[0192] or [0193] p=1, 2 or 3, n=1, m=1, 2, 3 or 4, and M, N,
A.sup.1, B.sup.1, B.sup.2, A.sup.2 and N form a 7 to 10 member
ring, the charge neutral metal amide compound has the Formula
IIe:
[0193] ##STR00047## [0194] p=1, 2 or 3, n=1, 2, 3 or 4, m=0 and N,
A.sup.1, B.sup.1, B.sup.2 and A.sup.2 form a 5 to 10 member ring,
the charge neutral metal amide compound has the Formula IIf:
[0194] ##STR00048## [0195] p=1, 2 or 3, n=1, 2, 3 or 4, m=0 and N,
A.sup.1, B.sup.1, B.sup.2 and A.sup.2 form a first 5 to 10 member
ring, and B.sup.1 and B.sup.2 are bridged to form a second 5 to 20
member ring, the charge neutral metal amide compound has the
Formula IIg:
[0195] ##STR00049## [0196] p=1, 2 or 3, n=1, m=0 and M, N, A.sup.1,
B.sup.1, B.sup.2, A.sup.2 and N form a 7 to 10 member ring, the
charge neutral metal amide compound has the Formula IIh:
##STR00050##
[0197] According to another aspect the charge neutral metal amide
compound of the hole injection layer may be selected from at least
one compound according to Formula IIIa, IIIb, IIIc, IIId, IIIe,
IIIf, IIIg, IIIh and/or IIIi,
wherein for A.sup.1 and A.sup.2 are SO.sub.2: [0198] p=1, 2 or 3,
n=1, 2, 3 or 4, m=1, 2, 3 or 4, the charge neutral metal amide
compound has the Formula IIIa:
[0198] ##STR00051## [0199] p=0, n=1, 2, 3 or 4, m=1, 2, 3 or 4, the
charge neutral metal amide compound has the Formula IIIb:
[0199] ##STR00052## [0200] p=1, 2 or 3, n=1, 2, 3 or 4, m=0, the
charge neutral metal amide compound has the Formula IIIc:
[0200] ##STR00053## [0201] p=1, 2 or 3, n=1, 2, 3 or 4, m=1, 2, 3
or 4 and N, SO.sub.2, B.sup.1, B.sup.2 and SO.sub.2 form a 5 to 10
member ring, the charge neutral metal amide compound has the
Formula IIId:
[0201] ##STR00054## [0202] p=1, 2 or 3, n=1, 2, 3 or 4, m=1, 2, 3
or 4 and N, SO.sub.2, B.sup.1, B.sup.2 and SO.sub.2 form a first 5
to 10 member ring, and B.sup.1 and B.sup.2 are bridged to form a
second 5 to 20 member ring, the charge neutral metal amide compound
has the Formula IIIe:
[0202] ##STR00055## [0203] p=1, 2 or 3, n=1, m=1, 2, 3 or 4 and M,
N, SO.sub.2, B.sup.1, B.sup.2, SO.sub.2 and N form a 7 to 10 member
ring, the charge neutral metal amide compound has the Formula
IIIf:
[0203] ##STR00056## [0204] p=1, 2 or 3, n=1, 2, 3 or 4, m=0 and N,
SO.sub.2, B.sup.1, B.sup.2 and SO.sub.2 form a 5 to 10 member ring,
the charge neutral metal amide compound has the Formula IIIg:
[0204] ##STR00057## [0205] p=1, 2 or 3, n=1, 2, 3 or 4, m=0 and N,
SO.sub.2, B.sup.1, B.sup.2 and SO.sub.2 form a first 5 to 10 member
ring, and B.sup.1 and B.sup.2 are bridged to form a second 5 to 20
member ring, the charge neutral metal amide compound has the
Formula IIIh:
[0205] ##STR00058## [0206] p=1, 2 or 3, n=1, 2, 3 or 4, m=0 and M,
N, SO.sub.2, B.sup.1, B.sup.2, SO.sub.2 and N form a 7 to 10 member
ring, the charge neutral metal amide compound has the Formula
IIIi:
##STR00059##
[0207] According to another aspect the charge neutral metal amide
compound of the hole injection layer may be selected from at least
one compound according to Formula IVa, IVb, IVc, IVd and/or
IVe,
wherein for A.sup.1 and A.sup.2 are POR.sup.8: [0208] p=1, 2 or 3,
m=1, 2, 3 or 4 and n=1, 2, 3 or 4, the charge neutral metal amide
compound has the Formula IVa:
[0208] ##STR00060## [0209] p=0, m=1, 2, 3 or 4 and n=1, 2, 3 or 4,
the charge neutral metal amide compound has the Formula IVb:
[0209] ##STR00061## [0210] p=1, 2 or 3, m=0 and n=1, 2, 3 or 4, the
charge neutral metal amide compound has the Formula IVc:
[0210] ##STR00062## [0211] p=1, 2 or 3, n=1, 2, 3 or 4, m=1, 2, 3
or 4 and N, POR.sup.8, B.sup.1, B.sup.2 and POR.sup.8 form a 5 to
10 member ring, the charge neutral metal amide compound has the
Formula (IVd):
[0211] ##STR00063## [0212] p=1, 2 or 3, n=1, 2, 3 or 4, m=0 and N,
POR.sup.8, B.sup.1, B.sup.2 and POR.sup.8 form a 5 to 10 member
ring, the charge neutral metal amide compound has the Formula
(IVe):
##STR00064##
[0213] According to another aspect the charge neutral metal amide
compound of the hole injection layer may be selected from at least
one compound according to Formula Va, Vb, Vc, Vd, Ve, Vf, Vg, Vh
and/or Vi,
wherein for A.sup.1 and A.sup.2 are CO: [0214] p=1, 2 or 3, m=1, 2,
3 or 4 and n=1, 2, 3 or 4, the charge neutral metal amide compound
has the Formula Va:
[0214] ##STR00065## [0215] p=0, n=1, 2, 3 or 4, m=1, 2, 3 or 4, the
charge neutral metal amide compound has the Formula Vb:
[0215] ##STR00066## [0216] p=1, 2 or 3, n=1, 2, 3 or 4, m=0, the
charge neutral metal amide compound has the Formula Vc:
[0216] ##STR00067## [0217] p=1, 2 or 3, n=1, 2, 3 or 4, m=1, 2, 3
or 4 and N, CO, B.sup.1, B.sup.2 and CO form a 5 to 10 member ring,
the charge neutral metal amide compound has the Formula Vd:
[0217] ##STR00068## [0218] p=1, 2 or 3, n=1, 2, 3 or 4, m=1, 2, 3
or 4 and N, CO, B.sup.1, B.sup.2 and CO form a first 5 to 10 member
ring, and B.sup.1 and B.sup.2 are bridged to form a second 5 to 20
member ring, the charge neutral metal amide compound has the
Formula Ve:
[0218] ##STR00069## [0219] p=1, 2 or 3, n=1, m=1, 2, 3 or 4 and M,
N, CO, B.sup.1, B.sup.2, CO and N form a 7 to 10 member ring, the
charge neutral metal amide compound has the Formula Vf:
[0219] ##STR00070## [0220] p=1, 2 or 3, n=1, 2, 3 or 4, m=0 and N,
CO, B.sup.1, B.sup.2 and CO form a 5 to 10 member ring, the charge
neutral metal amide compound has the Formula (Vg):
[0220] ##STR00071## [0221] p=1, 2 or 3, n=1, 2, 3 or 4, m=0 and N,
CO, B.sup.1, B.sup.2 and CO form a first 5 to 10 member ring, and
B.sup.1 and B.sup.2 form a second 5 to 20 member ring, the charge
neutral metal amide compound has the Formula Vh:
[0221] ##STR00072## [0222] p=1, 2 or 3, n=1, 2, 3 or 4, m=0 and M,
N, CO, B.sup.1, B.sup.2, CO and N form a 7 to 10 member ring, the
charge neutral metal amide compound has the Formula (Vi):
##STR00073##
[0223] According to another aspect the charge neutral metal amide
compound of the hole injection layer may be selected from at least
one compound according to Formula VIa, wherein for A.sup.1 is
SO.sub.2 and A.sup.2 is POR.sup.8: [0224] p=1, 2 or 3, m=1, 2, 3 or
4 and n=1, 2, 3 or 4, the charge neutral metal amide compound has
the Formula VIa:
##STR00074##
[0225] According to another aspect the charge neutral metal amide
compound of the hole injection layer may be selected from at least
one compound according to Formula Ib:
##STR00075##
wherein: [0226] A.sup.3 and A.sup.4 are same or independently
selected from CO, POR.sup.8 or SO.sub.2, preferably A.sup.3 and
A.sup.4 are selected same from CO, POR.sup.8 or SO.sub.2; [0227]
B.sup.3 and B.sup.4 are independently selected from substituted or
unsubstituted C.sub.1 to C.sub.20 alkyl, substituted or
unsubstituted C.sub.1 to C.sub.20 heteroalkyl, substituted or
unsubstituted C.sub.6 to C.sub.20 aryl, substituted or
unsubstituted C.sub.6 to C.sub.20 heteroaryl, preferably B.sup.3
and B.sup.4 are selected same; and [0228] M, N, A.sup.1, B.sup.1,
A.sup.2 and B.sup.2 form a 7 to 10 member ring.
[0229] According to another aspect the charge neutral metal amide
compound of the hole injection layer may be selected from at least
one compound according to Formula Id, wherein N, A.sup.1, B.sup.1,
A.sup.2 and B.sup.2 form a first 5 to 10 member ring and B.sup.1
and B.sup.2 are bridged to form a second ring of a substituted or
unsubstituted C.sub.6 to C.sub.20 aryl, or of a substituted or
unsubstituted C.sub.6 to C.sub.20 heteroaryl ring:
##STR00076##
[0230] According to another aspect the charge neutral metal amide
compound of the hole injection layer may be selected from at least
one fluorinated compound according to: [0231] Formula C1 to C16,
based on general formula Ia, wherein p=0, m=0, n=1, 2, 3 or 4 and
A.sup.1 and A.sup.2 are SO.sub.2:
[0231] ##STR00077## ##STR00078## [0232] Formula C17 to C23, based
on general Formula Ia, wherein n=1, 2, 3 or 4, A.sup.1 and A.sup.2
are CO:
[0232] ##STR00079## [0233] Formula C24 to C25, based on general
Formula Ia, wherein n=1, 2, 3 or 4, A.sup.1 and A.sup.2 are
POR.sup.8:
##STR00080##
[0234] According to another aspect the charge neutral metal amide
compound of the hole injection layer may be selected from at least
one fluorinated compound, based on general formula Ia, having the
Formula D1 to D24:
wherein p=0, m=0, n=1, 2, 3 or 4 and A.sup.1 and A.sup.2 are
SO.sub.2:
##STR00081## ##STR00082## ##STR00083## ##STR00084##
[0235] According to another aspect the charge neutral metal amide
compound of the hole injection layer may be selected from at least
one fluorinated compound, based on general formula Ia, having the
Formula F1 to F23:
wherein the charge neutral ligand L coordinates to the metal M:
##STR00085## ##STR00086## ##STR00087##
wherein [0236] R.sup.6 and R.sup.7 are independently selected from
C.sub.1 to C.sub.20 alkyl, C.sub.1 to C.sub.20 heteroalkyl, C.sub.6
to C.sub.20 aryl, heteroaryl with 5 to 20 ring-forming atoms,
halogenated or perhalogenated C.sub.1 to C.sub.20 alkyl,
halogenated or perhalogenated C.sub.1 to C.sub.20 heteroalkyl,
halogenated or perhalogenated C.sub.6 to C.sub.20 aryl, halogenated
or perhalogenated heteroaryl with 5 to 20 ring-forming atoms, or at
least one R.sup.6 and R.sup.7 are bridged and form a 5 to 20 member
ring, or the two R.sup.6 and/or the two R.sup.7 are bridged and
form a 5 to 40 member ring or form a 5 to 40 member ring comprising
an unsubstituted or C.sub.1 to C.sub.12 substituted
phenanthroline.
[0237] Charge neutral metal amide compounds which contain a
charge-neutral ligand L selected from mono and multidental ethers
or amines forming a 5 to 7 membered ring system with the metal,
preferably glycole ethers, ethylendiamine derivatives, even more
preferred diglyme, and/or
N1,N1,N2,N2-tetramethyl-1,2-ethanediamine,
N-((E,2E)-2-{[(E)-1,1-dimethylethyl]imino}ethylidene)-2-methyl-2-propanam-
ine can be preferably used as HIL-material.
[0238] Examples of charge neutral metal amides compounds with a
charge-neutral ligand L selected from mono and/or multidental
ethers or amines that can be preferably used as HIL-material having
the Formula F1, F2, F3, F4, F5 and/or F6:
##STR00088##
wherein [0239] R.sup.6 and R.sup.7 are independently selected from
C.sub.1 to C.sub.20 alkyl, C.sub.1 to C.sub.20 heteroalkyl, C.sub.6
to C.sub.20 aryl, heteroaryl with 5 to 20 ring-forming atoms,
halogenated or perhalogenated C.sub.1 to C.sub.20 alkyl,
halogenated or perhalogenated C.sub.1 to C.sub.20 heteroalkyl,
halogenated or perhalogenated C.sub.6 to C.sub.20 aryl, halogenated
or perhalogenated heteroaryl with 5 to 20 ring-forming atoms, or at
least one R.sup.6 and R.sup.7 are bridged and form a 5 to 20 member
ring, or the two R.sup.6 and/or the two R.sup.7 are bridged and
form a 5 to 40 member ring or form a 5 to 40 member ring comprising
an unsubstituted or C.sub.1 to C.sub.12 substituted
phenanthroline.
[0240] According to another aspect the charge neutral metal amide
compound of the hole injection layer may be selected preferably
from at least one fluorinated compound, based on general formula
Ia, having the Formula F18 to F23:
##STR00089##
[0241] According to another aspect the charge neutral metal amide
compound of the hole injection layer may be selected preferably
from at least one fluorinated compound, based on general formula
Ia, having the Formula F24 to F45:
wherein a halide, O, alkoxylate or amine bonds to the metal M:
##STR00090## ##STR00091##
wherein [0242] R.sup.1 to R.sup.5 are independently selected from
the group comprising H, C.sub.1 to C.sub.20 alkyl, C.sub.1 to
C.sub.20 heteroalkyl, unsubstituted or C.sub.1 to C.sub.12
substituted C.sub.6 to C.sub.20 aryl, unsubstituted or C.sub.1 to
C.sub.12 substituted heteroaryl with 5 to 20 ring-forming atoms,
halogenated or perhalogenated C.sub.1 to C.sub.20 alkyl,
halogenated or perhalogenated C.sub.1 to C.sub.20 heteroalkyl,
halogenated or perhalogenated C.sub.6 to C.sub.20 aryl, halogenated
or perhalogenated heteroaryl with 5 to 20 ring-forming atoms; or at
least one R.sup.1 and R.sup.4 and/or R.sup.2 and R.sup.3 and/or
R.sup.1 and R.sup.5 are bridged and form a 5 to 20 member cyclic
ring.
[0243] More preferred are compounds which comprise a ligand G.
Ligand G is selected from group VII elements, preferably chloride
Cl. Furthermore preferred are compounds wherein ligand G is
selected from an alkoxylate of formula F30, F31 and F35:
##STR00092##
wherein [0244] R.sup.1 is selected from the group comprising H,
C.sub.1 to C.sub.20 alkyl, C.sub.1 to C.sub.20 heteroalkyl,
unsubstituted or C.sub.1 to C.sub.12 substituted C.sub.6 to
C.sub.20 aryl, unsubstituted or C.sub.1 to C.sub.12 substituted
heteroaryl with 5 to 20 ring-forming atoms, halogenated or
perhalogenated C.sub.1 to C.sub.20 alkyl, halogenated or
perhalogenated C.sub.1 to C.sub.20 heteroalkyl, halogenated or
perhalogenated C.sub.6 to C.sub.20 aryl, halogenated or
perhalogenated heteroaryl with 5 to 20 ring-forming atoms.
[0245] According to another aspect the charge neutral metal amide
compound of the hole injection layer may be selected preferably
from at least one fluorinated compound, based on general formula
Ia, having the Formula F36 to F46:
##STR00093## ##STR00094##
[0246] In Table 1 below metal amide compounds according to formula
Ia are listed, which can be preferably used as hole injection layer
(HIL) material.
TABLE-US-00001 TABLE 1 Compounds of formula (Ia) which can be
suitable used for an hole injection layer (HIL) Metal amide
Structure CAS number Li TFSI ##STR00095## 90076-65-6 Na TFSI
##STR00096## 91742-21-1 K TFSI ##STR00097## 90076-67-8 Cs TFSI
##STR00098## 91742-16-4 Mg (TFSI).sub.2 ##STR00099## 133395-16-1 Fe
(TFSI).sub.3 ##STR00100## 207861-59-4 Ag TFSI ##STR00101##
189114-61-2 Mn (TFSI).sub.2 ##STR00102## 207861-55-0 Sn
(TFSI).sub.4 ##STR00103## 1019840-51-7 Sm (TFSI).sub.3 ##STR00104##
222733-67-7 Lu (TFSI).sub.3 ##STR00105## 887919-24-6 Sc
(TFSI).sub.3 ##STR00106## 176726-07-1 Nd (TFSI).sub.3 ##STR00107##
207861-67-4 U(O).sub.2 (TFSI).sub.2 ##STR00108## 943217-83-2 V(O)
(TFSI).sub.3 ##STR00109## --
[0247] Particularly preferred are metal amide compounds for use as
HIL-material listed in Table 2.
TABLE-US-00002 TABLE 2 Compounds of formula (Ia) which can be
suitable used for an hole injection layer (HIL) ##STR00110##
##STR00111## ##STR00112## ##STR00113## ##STR00114## ##STR00115##
##STR00116## ##STR00117## ##STR00118## ##STR00119## ##STR00120##
##STR00121## ##STR00122## ##STR00123## ##STR00124## ##STR00125##
##STR00126## ##STR00127## ##STR00128## ##STR00129## ##STR00130##
##STR00131## ##STR00132## ##STR00133## ##STR00134## ##STR00135##
##STR00136## ##STR00137## ##STR00138## ##STR00139## ##STR00140##
##STR00141## ##STR00142## ##STR00143## ##STR00144## ##STR00145##
##STR00146## ##STR00147## ##STR00148## ##STR00149## ##STR00150##
##STR00151## ##STR00152## ##STR00153## ##STR00154## ##STR00155##
##STR00156## ##STR00157## ##STR00158## ##STR00159## ##STR00160##
##STR00161## ##STR00162## ##STR00163## ##STR00164##
##STR00165##
Compounds Used in the Hole Transport Layer (HTL)
[0248] The HTL may be formed of any compound that is commonly used
to form a HTL. Compound that can be suitably used is disclosed for
example in Y. Shirota and H. Kageyama, Chem. Rev. 2007, 107,
953-1010 an incorporated by reference. Examples of the compound
that may be used to form the HTL 140 are: a carbazole derivative,
such as N-phenylcarbazole or polyvinylcarbazole; an amine
derivative having an aromatic condensation ring, such as
N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1-biphenyl]-4,4'-diamine
(T-1), or N,N'-di(naphthalene-1-yl)-N,N'-diphenyl benzydine
(alpha-NPD); and a triphenylamine-based compound, such as
4,4',4''-tris(N-carbazolyl)triphenylamine (T-10). Among these
compounds, T-10 can transport holes and inhibit excitons from being
diffused into the EML.
[0249] According to a preferred aspect, the hole transport layer
may comprises in addition a triarylamine compound having the
Formula VIIa:
##STR00166##
wherein: [0250] Ar.sup.1 and Ar.sup.2=independently selected from
substituted or unsubstituted C.sub.6 to C.sub.20 arylene; [0251]
Ar.sup.3 and Ar.sup.4=independently selected from substituted or
unsubstituted C.sub.6 to C.sub.20 aryl; [0252] Ar.sup.3 and
Ar.sup.4=independently selected from substituted or unsubstituted
C.sub.6 to C.sub.20 aryl or C.sub.5 to C.sub.40 heteroaryl; [0253]
R.sup.9=a single chemical bond, a unsubstituted or substituted
C.sub.1 to C.sub.6 alkyl and unsubstituted or substituted C.sub.1
to C.sub.5 heteroalkyl; [0254] q=0, 1 or 2; [0255] r=0 or 1;
wherein [0256] the substituents for Ar.sup.1 to Ar.sup.6 are
independently selected from C.sub.1 to C.sub.20 alkyl, C.sub.1 to
C.sub.20 heteroalkyl, or halide; and [0257] the substitutents for
R.sup.9 are independently selected from C.sub.1 to C.sub.6 alkyl,
C.sub.1 to C.sub.5 heteroalkyl, C.sub.6 to C.sub.20 aryl and
C.sub.5 to C.sub.20 heteroaryl.
[0258] According to a further preferred aspect, the hole transport
layer may comprises a triarylamine compound of Formula VIIa,
wherein Ar.sup.1 and Ar.sup.2 are Ph; Ar.sup.3 to Ar.sup.6 are
selected from phenyl, tolyl, xylyl, mesityl, biphenyl, 1-naphthyl,
2-napthyl, 2-(9,9-dialkyl-fluorenyl), 2-(9-alkyl-9'-aryl-fluorenyl)
and 2-(9,9-diaryl-fluorenyl); R.sup.9=single bond; r=1 and q=1.
[0259] According to a further preferred aspect, the hole transport
layer may comprises a triarylamine compound of Formula VIIa,
wherein Ar.sup.1 and Ar.sup.2 are independently selected from
phenyl and biphenyl; Ar.sup.3 to Ar.sup.6 are selected from phenyl,
tolyl, xylyl, mesityl, biphenyl, 1-naphthyl, 2-napthyl,
2-(9,9-dialkyl-fluorenyl), 2-(9-alkyl-9'-aryl-fluorenyl) and
2-(9,9-diaryl-fluorenyl); R.sup.9=single bond; r=1 and q=1.
[0260] According to a further preferred aspect, the hole transport
layer may comprises a triarylamine compound of Formula VIIa,
wherein Ar.sup.1 and Ar.sup.2 are phenyl; Ar.sup.3 to Ar.sup.6 are
selected from phenyl, tolyl, xylyl, mesityl, biphenyl, 1-naphthyl,
2-napthyl, 2-(9,9-dialkyl-fluorenyl), 2-(9-alkyl-9'-aryl-fluorenyl)
and 2-(9,9-diaryl-fluorenyl); R.sup.9=9,9'-fluorenyl; r=1 and
q=1.
[0261] According to a further preferred aspect, the hole transport
layer may comprises a triarylamine compound of Formula VIIa,
wherein Ar.sup.1 is phenyl; Ar.sup.3 to Ar.sup.6 are selected from
phenyl, tolyl, xylyl, mesityl, biphenyl, 1-naphthyl, 2-napthyl,
2-(9,9-dialkyl-fluorenyl), 2-(9-alkyl-9'-aryl-fluorenyl) and
2-(9,9-diaryl-fluorenyl); R.sup.9=single bond; r=0 and q=1. The
substituent on Ar.sup.1 is selected from phenyl, biphenyl,
2-(9,9-dialkyl-fluorenyl), 2-(9-alkyl-9'-aryl-fluorenyl) and
2-(9,9-diaryl-fluorenyl).
[0262] According to a further preferred aspect, the hole transport
layer may comprises a triarylamine compound of Formula VIIa,
wherein N, Ar.sup.1 and Ar.sup.3 form a carbazole ring; Ar.sup.2 is
phenyl or biphenyl; Ar.sup.3 to Ar.sup.6 are selected from phenyl,
tolyl, xylyl, mesityl, biphenyl, 1-naphthyl, 2-napthyl,
2-(9,9-dialkyl-fluorenyl), 2-(9-alkyl-9'-aryl-fluorenyl) and
2-(9,9-diaryl-fluorenyl); R.sup.9=single bond; r=1 and q=1.
[0263] Preferably in Formula VIIa the q may be selected from 1 or
2.
[0264] Compounds of formula VIIa that can be suitable used as
HTL-material may have an molecular weight suitable for thermal
vacuum deposition and HOMO levels that provides a good hole
transport performance into the emission layer.
[0265] According to a more preferred embodiment the Ar.sup.1 and
Ar.sup.2 of Formula VIIa may be independently selected from
phenylene, biphenylene, naphthylene, anthranylene, carbazolylene,
or fluorenylene, preferably from phenylene or biphenylene.
[0266] According to a more preferred embodiment the Ar.sup.3 to
Ar.sup.6 of Formula VIIa may be independently selected from phenyl,
biphenyl, terphenyl, quartphenyl, fluorenyl, napthyl, anthranyl,
phenanthryl, thiophenyl, fluorenyl, or carbazolyl.
[0267] Even more preferred, Ar.sup.3 to Ar.sup.6 of Formula VIIa
may be independently selected from phenyl, biphenyl, fluorenyl,
napthyl, thiopheneyl, fluorenyl, or carbazolyl.
[0268] At least two of Ar.sup.1 to Ar.sup.6 of Formula VIIa may
form a cyclic structure, for example Ar.sup.1 and Ar.sup.3; or
Ar.sup.1 and Ar.sup.4; or Ar.sup.2 and Ar.sup.5; or Ar.sup.2 and
Ar.sup.6; may be a carbazole, phenazoline or phenoxazine ring.
[0269] Further preferred, at least one of Ar.sup.1 to Ar.sup.6 of
Formula VIIa may be unsubstituted, even more preferred at least two
of Ar.sup.1 to Ar.sup.6 of Formula VII may be unsubstituted.
Compounds of formula VIIa, wherein not all Ar.sup.1 to Ar.sup.6 are
substituted are particularly suited for vacuum thermal
deposition.
[0270] Preferably, the hole transport layer comprises a
triarylamine compound of formula VIIa I, wherein the substituents
on Ar.sup.3 to Ar.sup.6 are independently selected from C.sub.1 to
C.sub.12 alkyl, C.sub.1 to C.sub.12 alkoxy or halide, preferably
from C.sub.1 to C.sub.8 alkyl, C.sub.1 to C.sub.8 heteroalkyl or
fluoride, even more preferred from C.sub.1 to C.sub.5 alkyl,
C.sub.1 to C.sub.5 heteroalkyl or fluoride.
[0271] Preferably, the hole transport layer comprises a
triarylamine compound of formula VIIa, wherein the substituents on
Ar.sup.3 to Ar.sup.6 are independently selected from C.sub.1 to
C.sub.12 alkyl or halide, preferably from C.sub.1 to C.sub.8 alkyl,
even more preferred from C.sub.1 to C.sub.5 alkyl. When the
substituents are selected from alkyl groups, the HOMO level of the
hole transport layer may have a HOMO level suitable for good hole
transport into the emission layer, in particular of phosphorescent
blue and green emitters and emission which relies on TADF
(thermally activated delayed fluorescence) and the OLED may have
low voltage, high efficiency and good stability.
[0272] Examples of particularly preferred compounds of Formula VIIa
are shown in Table 3.
TABLE-US-00003 TABLE 3 Triarylamine compounds of formula VIIa HOMO
Name Structure (eV) N,N,N',N'-Tetrakis(4- methylphenyl)-benzidine
(T-1) ##STR00167## -4.99 N4,N4,N4',N4'- tetra(biphenyl-4-
yl)biphenyl-4,4'-diamine (T-2) ##STR00168## -5.08
Biphenyl-4-yl(9,9- diphenyl-9H-fluoren-2- yl)-[4-(9-phenyl-9H-
carbazol-3-yl)phenyl]- amine (T-3) ##STR00169## -5.10
N,N'-Bis(naphthalen-1- yl)-N,N'-bis(phenyl)- benzidine (T-4)
##STR00170## -5.11 N1,N3-di([1,1'- biphenyl]-4-yl)-5-(9,9-
dimethyl-9H-fluoren-2- yl)-N1,N3-bis(3,5- dimethylphenyl)benzene-
1,3-diamine (T-5) ##STR00171## -5.18 N1,N3-di([1,1'-
biphenyl]-4-yl)-5-(9,9- dimethyl-9H-fluoren-2- yl)-N1,N3-
dimesitylbenzene-1,3- diamine (T-6) ##STR00172## -5.22
N,N'-((9H-fluorene-9,9- diyl)bis(4,1- phenylene))bis(N-([1,1'-
biphenyl]-4-yl)-[1,1'- biphenyl]-4-amine) (T-7) ##STR00173## -5.24
N4,N4''-di(naphthalen-1- yl)-N4,N4''-diphenyl-
[1,1':4',1''-terphenyl]- 4,4''-diamine (CAS 139255-16-6) (T-8)
##STR00174## -5.25 4,4'-Bis-(N-(1-naphthyl)- N-phenyl-amino)-
quaterphenyl (CAS 650609-47-5) (T-9) ##STR00175## -5.33
4,4',4''-Tris(carbazol-9- yl)-triphenylamine (T-10) ##STR00176##
-5.7
[0273] According to another aspect, the hole injection layer (HIL)
may comprises about .ltoreq.2 wt.-% of a triarylamine compound,
wherein the triarylamine compound differs from the charge neutral
metal amide compound according to formula Ia to Id.
[0274] According to another aspect, the hole injection layer (HIL)
may comprises about .ltoreq.2 wt.-% of a triarylamine compound
according to the general Formula VIIa.
[0275] According to another aspect, the hole injection layer (HIL)
may be free of a triarylamine compound according to the general
Formula VIIa.
[0276] More preferred the hole injection layer (HIL) may be free of
a triarylamine compound.
[0277] Other examples of the compounds that may be used for forming
the HTL 140 are oligothiophenes and phthalocyanines disclosed for
example in Yasuhiko Shirota and Hiroshi Kageyama, Chem. Rev. 2007,
107, 953-1010 and in Facchetti, Materials Today 10, 2007, 28 and
incorporated by reference.
Compounds Used in the Electron Transport Layer (ETL)
[0278] The OLED according to the present invention may not contain
an electron transport layer (ETL). However, the OLED according to
the present invention may optional contain an electron transport
layer (ETL).
[0279] According to various embodiments the OLED may comprises an
electron transport layer or an electron transport layer stack
comprising at least a first electron transport layer and at least a
second electron transport layer.
[0280] According to various embodiments of the OLED of the present
invention the electron transport layer may comprises at least one
matrix compound.
[0281] According to various embodiments of the OLED the matrix
compound may be selected from: [0282] an anthracene based compound
or a heteroaryl substituted anthracene based compound, preferably
2-(4-(9,10-di(naphthalen-2-yl)anthracene-2-yl)phenyl)-1-phenyl-1H-benzo[d-
]imidazole and/or
N4,N4''-di(naphthalen-1-yl)-N4,N4''-diphenyl-[1,1':4',1''-terphenyl]-4,4'-
'-diamine; [0283] a phosphine oxide based compound, preferably
(3-(dibenzo[c,h]acridin-7-yl)phenyl)diphenylphosphine oxide and/or
phenyl bis(3-(pyren-1-yl)phenyl)phosphine oxide and/or
3-Phenyl-3H-benzo[b]dinaphtho[2,1-d:1',2'-f]phosphepine-3-oxide; or
[0284] a substituted phenanthroline compound, preferably
2,4,7,9-tetraphenyl-1,10-phenanthroline,
4,7-diphenyl-2,9-di-p-tolyl-1,10-phenanthroline, or
2,9-di(biphenyl-4-yl)-4,7-diphenyl-1,10-phenanthroline.
[0285] According to various embodiments of the OLED the matrix
compound of the electron transport layer may be preferably selected
from: [0286] a phosphine oxide based compound, preferably
(3-(dibenzo[c,h]acridin-7-yl)phenyl)diphenylphosphine oxide,
3-phenyl-3H-benzo[b]dinaphtho[2,1-d:1',2'-f]phosphepine-3-oxide
and/or phenyl bis(3-(pyren-1-yl)phenyl)phosphine oxide; or a
substituted phenanthroline compound, preferably
2,4,7,9-tetraphenyl-1,10-phenanthroline,
4,7-diphenyl-2,9-di-p-tolyl-1,10-phenanthroline, or
2,9-di(biphenyl-4-yl)-4,7-diphenyl-1,10-phenanthroline.
[0287] According to various embodiments of the OLED the matrix
compound of the electron transport layer may be more preferred
selected from: [0288] a phosphine oxide based compound, preferably
(3-(dibenzo[c,h]acridin-7-yl)phenyl)diphenylphosphine oxide,
3-phenyl-3H-benzo[b]dinaphtho[2,1-d:1',2'-f]phosphepine-3-oxide
and/or phenyl bis(3-(pyren-1-yl)phenyl)phosphine oxide.
[0289] According to various embodiments of the OLED of the present
invention the thicknesses of the electron transport layer may be in
the range of about .gtoreq.0.5 nm to about .ltoreq.95 nm,
preferably of about .gtoreq.3 nm to about .ltoreq.80 nm, further
preferred of about .gtoreq.5 nm to about .ltoreq.60 nm, also
preferred of about .gtoreq.6 nm to about .ltoreq.40 nm, in addition
preferred about .gtoreq.8 nm to about .ltoreq.20 nm and more
preferred of about .gtoreq.10 nm to about .ltoreq.18 nm.
[0290] According to various embodiments of the OLED of the present
invention the thicknesses of the electron transport layer stack can
be in the range of about .gtoreq.25 nm to about .ltoreq.100 nm,
preferably of about .gtoreq.30 nm to about .ltoreq.80 nm, further
preferred of about .gtoreq.35 nm to about .ltoreq.60 nm, and more
preferred of about .gtoreq.36 nm to about .ltoreq.40 nm.
[0291] According to various embodiments of the OLED of the present
invention the electron transport layer may comprises: [0292] a)
about .gtoreq.10 wt.-% to about .ltoreq.70 wt.-%, preferably about
.gtoreq.20 wt.-% to about .ltoreq.65 wt.-% and also preferred about
.gtoreq.50 wt.-% to about .ltoreq.60 wt.-% of a lithium halide or
an lithium organic complex of a lithium quinolate, a lithium
borate, a lithium phenolate and/or a lithium Schiff base,
preferably of a lithium quinolate complex has the formula I, II or
III:
[0292] ##STR00177## [0293] wherein [0294] A1 to A6 are same or
independently selected from CH, CR, N, O, [0295] R is same or
independently selected from hydrogen, halogen, alkyl or aryl or
heteroaryl with 1 to 20 carbon atoms, and more preferred of a
lithium 8-hydroxyquinolate; [0296] b) about .ltoreq.90 wt.-% to
about .gtoreq.30 wt.-%, preferably about .ltoreq.80 wt.-% to about
.gtoreq.35 wt.-% and also preferred about .ltoreq.50 wt.-% to about
.gtoreq.40 wt.-% of a matrix compound of: [0297] an anthracene
based compound or a hetero substituted anthracene based compound,
preferably
2-(4-(9,10-di(naphthalen-2-yl)anthracene-2-yl)phenyl)-1-phenyl-1H-benzo[d-
]imidazole and/or
N4,N4''-di(naphthalen-1-yl)-N4,N4''-diphenyl-[1,1':4',1''-terphenyl]-4,4'-
'-diamine; or [0298] a phosphine oxide based compound, preferably
(3-(dibenzo[c,h]acridin-7-yl)phenyl)diphenylphosphine oxide and/or
phenyl bis(3-(pyren-1-yl)phenyl)phosphine oxide and/or
3-Phenyl-3H-benzo[b]dinaphtho[2,1-d:1,2'-f]phosphepine-3-oxide; or
[0299] a substituted phenanthroline compound, preferably
2,4,7,9-tetraphenyl-1,10-phenanthroline,
4,7-diphenyl-2,9-di-p-tolyl-1,10-phenanthroline, or
2,9-di(biphenyl-4-yl)-4,7-diphenyl-1,10-phenanthroline; whereby
[0300] more preferred is a phosphine oxide based compound and most
preferred is (3-(dibenzo[c,h]acridin-7-yl)phenyl)diphenylphosphine
oxide; based on the total weight of the electron transport
layer.
[0301] According to one embodiment of the OLED, the electron
transport layer comprises of about .gtoreq.50 wt.-% to about
.ltoreq.60 wt.-% of a first lithium halide or a first lithium
organic complex and about .ltoreq.50 wt.-% to about .gtoreq.40
wt.-% of a matrix compound of: [0302] a phosphine oxide based
compound, preferably
(3-(dibenzo[c,h]acridin-7-yl)phenyl)diphenylphosphine oxide,
3-phenyl-3H-benzo[b]dinaphtho[2,1-d: 1,2'-f]phosphepine-3-oxide
and/or phenyl bis(3-(pyren-1-yl)phenyl)phosphine oxide; or [0303] a
substituted phenanthroline compound, preferably
2,4,7,9-tetraphenyl-1,10-phenanthroline,
4,7-diphenyl-2,9-di-p-tolyl-1,10-phenanthroline, or
2,9-di(biphenyl-4-yl)-4,7-diphenyl-1,10-phenanthroline.
[0304] The light-emitting diode (OLED) may comprises at least two
electrodes, an anode electrode and a second cathode electrode.
[0305] The electron transport layer/s or electron transport layer
stack is not an electrode. The electron transport layer/s or
electron transport layer are sandwiched between two electrodes,
namely sandwiched between an anode and a second cathode.
[0306] The ETL may be formed optional on an EML or on the HBL if
the HBL is formed. The ETL includes a first layer including a first
lithium halide or a first lithium organic complex; and optional a
second electron transport layer including a second lithium halide
or a second lithium organic complex, wherein optional the first
lithium organic complex is not the same as the second lithium
organic complex and wherein the first lithium halide is not the
same as the second lithium halide.
[0307] The ETL includes a first layer comprising a first matrix
compound and a lithium halide or a lithium organic complex; and
optional a second electron transport layer comprising a second
matrix compound and a metal dopant selected from a group comprising
alkali, alkaline earth and rare earth metals.
[0308] The ETL includes a first layer comprising a first matrix
compound and a lithium halide or a lithium organic complex; and
optional a second electron transport layer comprising a second
matrix compound and is free of dopant.
[0309] The ETL may have a stacked structure, preferably of two
ETL-layers, so that injection and transport of electrons may be
balanced and holes may be efficiently blocked. In a conventional
OLED, since the amounts of electrons and holes vary with time,
after driving is initiated, the number of excitons generated in an
emission area may be reduced. As a result, a carrier balance may
not be maintained, so as to reduce the lifetime of the OLED.
[0310] However, in the ETL, the first layer and the second layer
may have similar or identical energy levels, so that the carrier
balance may be uniformly maintained, while controlling the
electron-transfer rate.
[0311] Matrix compound for the electron layer that can be suitable
used are selected from the group comprising anthracen compounds,
preferably
2-(4-(9,10-di(naphthalen-2-yl)anthracen-2-yl)phenyl)-1-phenyl-1H-benzo[d]-
imidazole
[0312] Anthracene compounds that can be used as matrix materials
are disclosed in U.S. Pat. No. 6,878,469 B and incorporated by
reference.
[0313] Other matrix compounds that can be used are
diphenylphosphine oxide, preferably
(3-(dibenzo[c,h]acridin-7-yl)phenyl)diphenylphosphine oxide,
phenylbis(3-(pyren-1-yl)phenyl)phosphine oxide,
3-phenyl-3H-benzo[b]dinaphtho[2,1-d:1',2'-f]phosphepine-3-oxide,
phenyldi(pyren-1-yl)phosphine oxide.
[0314] Diphenylphosphine oxide compounds that can be used as matrix
materials are disclosed in EP 2395571 A1, WO2013079217 A1, EP
13187905, EP13199361 and JP2002063989 A1, incorporated by
reference.
[0315] Other suitable matrix compounds that can be used are
phenanthroline compounds, preferably selected from the group
comprising of 2,4,7,9-tetraphenyl-1,10-phenanthroline,
4,7-diphenyl-2,9-di-p-tolyl-1,10-phenanthroline, and
2,9-di(biphenyl-4-yl)-4,7-diphenyl-1,10-phenanthroline.
Phenanthroline compounds that can be used as matrix materials are
disclosed in EP 1786050 A1 and incorporated by reference.
[0316] The matrix compound of the electron transport layer may be a
compound that efficiently transports electrons, such as an
anthracene-based compound, diphenylphosphine oxide based compound,
or a phenanthroline based compound, preferably a matrix compound
mentioned in Table 4. For example, the matrix compound of the
electron transport layer may be selected from the group consisting
of Compound 5, a compound represented by Formula 2, and a compound
represented by Formula 3 below:
##STR00178##
[0317] In Formulae 2 and 3, R.sub.1 to R.sub.6 are each
independently a hydrogen atom, a halogen atom, a hydroxy group, a
cyano group, a substituted or unsubstituted C.sub.1-C.sub.30 alkyl
group, a substituted or unsubstituted C.sub.1-C.sub.30 alkoxy
group, a substituted or unsubstituted C.sub.1-C.sub.30 acyl group,
a substituted or unsubstituted C.sub.2-C.sub.30 alkenyl group, a
substituted or unsubstituted C.sub.2-C.sub.30 alkynyl group, a
substituted or unsubstituted C.sub.6-C.sub.30 aryl group, or a
substituted or unsubstituted C.sub.3-C.sub.30 heteroaryl group. At
least two adjacent R.sub.1 to R.sub.6 groups are optionally bonded
to each other, to form a saturated or unsaturated ring. L.sub.1 is
a bond, a substituted or unsubstituted C.sub.1-C.sub.30 alkylene
group, a substituted or unsubstituted C.sub.6-C.sub.30 arylene
group, or a substituted or unsubstituted C.sub.3-C.sub.30 hetero
arylene group. Q.sub.1 through Q.sub.9 are each independently a
hydrogen atom, a substituted or unsubstituted C.sub.6-C.sub.30 aryl
group, or a substituted or unsubstituted C.sub.3-C.sub.30 hetero
aryl group, and "a" is an integer from 1 to 10.
[0318] For example, R.sup.1 to R.sub.6 may be each independently
selected from the group consisting of a hydrogen atom, a halogen
atom, a hydroxy group, a cyano group, a methyl group, an ethyl
group, a propyl group, a butyl group, a methoxy group, an ethoxy
group, a propoxy group, a butoxy group, a phenyl group, a naphthyl
group, an anthryl group, a pyridinyl group, and a pyrazinyl
group.
[0319] In particular, in Formula 2 and/or 3, R.sub.1 to R.sub.4 may
each be a hydrogen atom, R.sub.5 may be selected from the group
consisting of a halogen atom, a hydroxy group, a cyano group, a
methyl group, an ethyl group, a propyl group, a butyl group, a
methoxy group, an ethoxy group, a propoxy group, a butoxy group, a
phenyl group, a naphthyl group, an anthryl group, a pyridinyl
group, and a pyrazinyl group. In addition, in Formula 3, R.sub.1 to
R.sub.6 may each be a hydrogen atom.
[0320] For example, in Formula 2 and/or 3, Q.sub.1 to Q.sub.9 are
each independently a hydrogen atom, a phenyl group, a naphthyl
group, an anthryl group, a pyridinyl group, and a pyrazinyl group.
In particular, in Formulae 2 and/or 3, Q.sub.1, Q.sub.3-Q.sub.6,
Q.sub.8 and Q.sub.9 are hydrogen atoms, and Q.sub.2 and Q.sub.7 may
be each independently selected from the group consisting of a
phenyl group, a naphthyl group, an anthryl group, a pyridinyl
group, and a pyrazinyl group.
[0321] For example, L.sub.1, in Formula 2 and/or 3, may be selected
from the group consisting of a phenylene group, a naphthylene
group, an anthrylene group, a pyridinylene group, and a
pyrazinylene group. In particular, L.sub.1 may be a phenylene group
or a pyridinylene group. For example, "a" may be 1, 2, or, 3.
[0322] The matrix compound for the ETL-layer may be further
selected from Compound 5, 6, or 7 below:
##STR00179##
TABLE-US-00004 TABLE 4 Chemical structures of matrix materials that
can be suitable used for ETL-layer Internal name IUPAC name
Structure Reference MX 1 2-(4-(9,10-di(naphthalen-2-
yl)anthracen-2-yl)phenyl)-1- phenyl-1H- benzo[d]imidazole
##STR00180## US 6878469 B2. MX 2 (3-(dibenzo[c,h]acridin-7-
yl)phenyl)diphenylphosphine oxide ##STR00181## EP 2395571B1,
WO2013079217A1 MX 3 Phenylbis(3-(pyren-1- yl)phenyl)phosphine oxide
##STR00182## EP13187905.8 MX 4 3-Phenyl-3H- benzo[b]dinaphtho[2,1-
d:1',2'-f]phosphepine-3- oxide ##STR00183## EP13199361.0 MX 5
Phenyldi(pyren-1- yl)phosphine oxide ##STR00184## JP4876333 MX 6
2,4,7,9-tetraphenyl-1,10- phenanthroline ##STR00185## EP1786050 MX
8 2,9-di(biphenyl-4-yl)-4,7- diphenyl-1,10- phenanthroline
##STR00186## EP1786050 MX 9 4,7-diphenyl-2,9-di-p-tolyl-
1,10-phenanthroline ##STR00187## EP1786050
[0323] The electron transport layer may comprises a lithium halide
or a lithium organic complex.
[0324] Suitable organic ligands to form a lithium organic complex
that can be used for the electron transport layer are disclosed,
and incorporated by reference, for example in US 2014/0048792 and
Kathirgamanathan, Poopathy; Arkley, Vincent; Surendrakumar,
Sivagnanasundram; Chan, Yun F.; Ravichandran, Seenivasagam;
Ganeshamurugan, Subramaniam; Kumaraverl, Muttulingam; Antipan-Lara,
Juan; Paramaswara, Gnanamolly; Reddy, Vanga R., Digest of Technical
Papers--Society for Information Display International Symposium
(2010), 41(Bk. 1), 465-468.
TABLE-US-00005 TABLE 5 Lithium organic complex that can be suitable
used for the ETL-layer IUPAC name Structure Reference LiQ lithium
8-hydroxyquinolate ##STR00188## WO 2013079217 A1 Li-1 lithium
tetra(1H-pyrazol-1- yl)borate ##STR00189## WO 2013079676 A1 Li-2
lithium 2-(diphenyl- phosphoryl)phenolate ##STR00190## WO
2013079678 A1 Li-3 lithium 2-(pyridin-2- yl)phenolate ##STR00191##
JP2 008195623 Li-4 lithium 2-(1-phenyl-1H- benzo[d]imidazol-2-
yl)phenolate ##STR00192## JP 2001291593, Li-5 lithium
2-(benzo[d]oxazol-2- yl)phenolate ##STR00193## US 20030165711 Li-6
lithium 2-(diphenyl- phosphoryl)pyridin-3-olate ##STR00194## EP
2724388
[0325] The organic ligand of the lithium organic complex of the
electron transport layer may be selected from the group comprising
a quinolate, a borate, a phenolate, a pyridinolate or a Schiff base
ligand, or Table 5; [0326] preferably the lithium quinolate complex
has the formula I:
##STR00195##
[0326] wherein [0327] A1 to A6 are same or independently selected
from CH, CR, N, O; [0328] R is same or independently selected from
hydrogen, halogen, alkyl or aryl or heteroaryl with 1 to 20 carbon
atoms; and more preferred A1 to A6 are CH; [0329] preferably the
borate based organic ligand is a tetra(1H-pyrazol-1-yl)borate;
[0330] preferably the phenolate is a 2-(pyridin-2-yl)phenolate or a
2-(diphenylphosphoryl)phenolate; [0331] preferably the lithium
Schiff base has the structure 100, 101, 102 or 103:
[0331] ##STR00196## [0332] more preferred the lithium organic
complex is selected from a compound of Table 2X. The lithium halide
of the electron transport layer may be selected from the group
comprising a LiF, LiCl, LiBr or LiJ, and preferably LiF.
[0333] The ETL may be formed on the EML by vacuum deposition, spin
coating, slot-die coating, printing, casting, or the like. When the
ETL is formed by vacuum deposition or spin coating, the deposition
and coating conditions may be similar to those for formation of the
HIL 130. However, the deposition and coating conditions may vary,
according to a compound that is used to form the ETL.
Substrate
[0334] The substrate may be any substrate that is commonly used in
manufacturing of organic light-emitting diodes. If light is emitted
through the substrate, the substrate may be a transparent material,
for example a glass substrate or a transparent plastic substrate,
having excellent mechanical strength, thermal stability,
transparency, surface smoothness, ease of handling, and
waterproofness. If light is emitted through the top surface, the
substrate may be a transparent or non-transparent material, for
example a glass substrate, a plastic substrate, a metal substrate
or a silicon substrate.
Anode Electrode
[0335] The anode electrode may be formed by depositing or
sputtering a compound that is used to form the anode electrode. The
compound used to form the anode electrode may be a high
work-function compound, so as to facilitate hole injection. The
anode material may also be selected from a low work function
material (i.e. Aluminum). The anode electrode may be a transparent
or reflective electrode. Transparent conductive compounds, such as
indium tin oxide (ITO), indium zinc oxide (IZO), tin-dioxide
(SnO.sub.2), and zinc oxide (ZnO), may be used to form the anode
electrode 120. The anode electrode 120 may also be formed using
magnesium (Mg), aluminum (Al), aluminum-lithium (Al--Li), calcium
(Ca), magnesium-indium (Mg--In), magnesium-silver (Mg--Ag), silver
(Ag), gold (Au), or the like.
[0336] The HIL may be formed on the anode electrode by vacuum
deposition, spin coating, printing, casting, slot-die coating,
Langmuir-Blodgett (LB) deposition, or the like. When the HIL is
formed using vacuum deposition, the deposition conditions may vary
according to the compound that is used to form the HIL, and the
desired structure and thermal properties of the HIL. In general,
however, conditions for vacuum deposition may include a deposition
temperature of 100.degree. C. to 500.degree. C., a pressure of
10.sup.-8 to 10.sup.-3 torr (1 torr equals 133.322 Pa), and a
deposition rate of 0.1 to 10 nm/sec.
HIL--Forming Conditions
[0337] When the HIL is formed using spin coating or printing,
coating conditions may vary according to a compound that is used to
form the HIL, and the desired structure and thermal properties of
the HIL. For example, the coating conditions may include a coating
speed of about 2000 rpm to about 5000 rpm, and a thermal treatment
temperature of about 80.degree. C. to about 200.degree. C. Thermal
treatment removes a solvent after the coating is performed.
HTL--Forming Conditions
[0338] The hole transport layer (HTL) may be formed on the HIL by
vacuum deposition, spin coating, slot-die coating, printing,
casting, Langmuir-Blodgett (LB) deposition, or the like. When the
HTL is formed by vacuum deposition or spin coating, the conditions
for deposition and coating may be similar to those for the
formation of the HIL. However, the conditions for the vacuum or
solution deposition may vary, according to the compound that is
used to form the HTL.
Emission Layer (EML)
[0339] The EML may be formed on the HTL by vacuum deposition, spin
coating, slot-die coating, printing, casting, LB, or the like. When
the EML is formed using vacuum deposition or spin coating, the
conditions for deposition and coating may be similar to those for
the formation of the HIL. However, the conditions for deposition
and coating may vary, according to the compound that is used to
form the EML.
[0340] The emission layer (EML) may be formed of a combination of a
host and a dopant. Example of the host are Alq3,
4,4'-N,N'-dicarbazole-biphenyl (CBP), poly(n-vinylcarbazole) (PVK),
9,10-di(naphthalene-2-yl)anthracene (ADN),
4,4',4''-Tris(carbazol-9-yl)-triphenylamine (TCTA),
1,3,5-tris(N-phenylbenzimidazole-2-yl)benzene (TPBI),
3-tert-butyl-9,10-di-2-naphthylanthracenee (TBADN), distyrylarylene
(DSA), Bis(2-(2-hydroxyphenyl)benzo-thiazolate)zinc (Zn(BTZ) 2), E3
below, AND, Compound 1 below, and Compound 2 below.
##STR00197##
[0341] The dopant may be a phosphorescent or fluorescent emitter.
Phosphorescent emitters are preferred due to their higher
efficiency
[0342] Examples of a red dopant are PtOEP, Ir(piq) 3, and Btp
2Ir(acac), but are not limited thereto. These compounds are
phosphorescent emitters, however, fluorescent red dopants could
also be used.
##STR00198##
[0343] Examples of a phosphorescent green dopant are Ir(ppy) 3
(ppy=phenylpyridine), Ir(ppy) 2(acac), Ir(mpyp) 3 are shown below.
Compound 3 is an example of a fluorescent green emitter and the
structure is shown below.
##STR00199##
[0344] Examples of a phosphorescent blue dopant are F.sub.2Irpic,
(F.sub.2ppy).sub.2Ir(tmd) and Ir(dfppz) 3, ter-fluorene, the
structures are shown below. 4,4'-bis(4-diphenyl amiostyryl)biphenyl
(DPAVBi), 2,5,8,11-tetra-tert-butyl perylene (TBPe), and Compound 4
below are examples of fluorescent blue dopants.
##STR00200##
[0345] The amount of the dopant may be in the range of about 0.01
to about 50 parts by weight, based on 100 parts by weight of the
host. The EML may have a thickness of about 10 nm to about 100 nm,
for example, about 20 nm to about 60 nm. When the thickness of the
EML is within this range, the EML may have excellent light
emission, without a substantial increase in driving voltage.
Hole Blocking Layer (HBL)
[0346] When the EML comprises a phosphorescent dopant, a hole
blocking layer (HBL) may be formed on the EML, by using vacuum
deposition, spin coating, slot-die coating, printing, casting, LB
deposition, or the like, in order to prevent the diffusion of
triplet excitons or holes into the ETL.
[0347] When the HBL is formed using vacuum deposition or spin
coating, the conditions for deposition and coating may be similar
to those for the formation of the HIL. However, the conditions for
deposition and coating may vary, according to the compound that is
used to form the HBL. Any compound that is commonly used to form a
HBL may be used. Examples of compounds for forming the HBL include
an oxadiazole derivative, a triazole derivative, and a
phenanthroline derivative.
[0348] The HBL may have a thickness of about 5 nm to about 100 nm,
for example, about 10 nm to about 30 nm. When the thickness of the
HBL is within this range, the HBL may have excellent hole-blocking
properties, without a substantial increase in driving voltage.
Electron Injection Layer (EIL)
[0349] The optional EIL, which may facilitates injection of
electrons from the cathode, may be formed on the ETL, preferably
directly on the electron transport layer. Examples of materials for
forming the EIL include LiF, NaCl, CsF, Li.sub.2O, BaO, Ca, Ba, Yb,
Mg which are known in the art. Deposition and coating conditions
for forming the EIL are similar to those for formation of the HIL,
although the deposition and coating conditions may vary, according
to a material that is used to form the EIL.
[0350] The thickness of the EIL may be in the range of about 0.1 nm
to 10 nm, for example, in the range of 0.5 nm to 9 nm. When the
thickness of the EIL is within this range, the EIL may have
satisfactory electron-injecting properties, without a substantial
increase in driving voltage.
Cathode Electrode
[0351] The cathode electrode is formed on the EIL if present. The
cathode electrode may be a cathode, which is an electron-injecting
electrode. The cathode electrode may be formed of a metal, an
alloy, an electrically conductive compound, or a mixture thereof.
The cathode electrode may have a low work function. For example,
the cathode electrode may be formed of lithium (Li), magnesium
(Mg), aluminum (Al), aluminum (Al)-lithium (Li), calcium (Ca),
barium (Ba), ytterbium (Yb), magnesium (Mg)-indium (In), magnesium
(Mg)-silver (Ag), or the like. In addition, the cathode electrode
may be formed of a transparent conductive material, such as ITO or
IZO.
[0352] The thickness of the cathode electrode may be in the range
of about 5 nm to 1000 nm, for example, in the range of 10 nm to 100
nm. When the cathode electrode is in the range of 5 nm to 50 nm,
the electrode will transparent even if a metal or metal alloy is
used.
[0353] Since the layers of the ETL have similar or identical energy
levels, the injection and transport of the electrons may be
controlled, and the holes may be efficiently blocked. Thus, the
OLED may have long lifetime.
Light-Emitting Diode (OLED)
[0354] According to another aspect of the present invention, there
is provided an organic light-emitting diode (OLED) comprising: a
substrate; a anode electrode formed on the substrate; a hole
injection layer comprising a metal amide according to the
invention, a hole transport layer, an emission layer, and a cathode
electrode.
[0355] According to another aspect of the present invention, there
is provided an organic light-emitting diode (OLED) comprising a
hole injection layer according to the invention and an emission
layer.
[0356] According to another aspect of the present invention, there
is provided an organic light-emitting diode (OLED) comprising:
[0357] an anode, a hole injection layer according to the invention
and an emission layer, wherein the hole injection layer is direct
arranged on the anode and the emission layer is direct arranged on
the hole injection layer; or [0358] an anode, a hole injection
layer according to the invention, a hole transport layer and an
emission layer, wherein the composition of the hole injection layer
is different to the composition of the hole transport layer.
[0359] According to another aspect of the present invention, there
is provided an organic light-emitting diode (OLED) comprising:
[0360] an anode, a hole injection layer according to the invention
and an emission layer, wherein the hole injection layer is direct
arranged on the anode and the emission layer is direct arranged on
the hole injection layer; or [0361] an anode, a hole injection
layer according to the invention, a hole transport layer and an
emission layer, wherein the composition of the hole injection layer
is different to the composition of the hole transport layer;
wherein the hole injection layer comprises the charge neutral metal
amide compound in the range of about .gtoreq.50 wt.-% to about
.ltoreq.100 wt.-%, preferably about .gtoreq.60 wt.-% to about
.ltoreq.100 wt.-%, further preferred about .gtoreq.70 wt.-% to
about .ltoreq.100 wt.-%, in addition preferred about .gtoreq.80
wt.-% to about .ltoreq.100 wt.-%, or about .gtoreq.95 wt.-% to
about .ltoreq.100 wt.-%, or about .gtoreq.98 wt.-% to about
.ltoreq.100 wt.-%, or about .gtoreq.99 wt.-% to about .ltoreq.100
wt.-%, and more preferred about .gtoreq.90 wt.-% to about
.ltoreq.100 wt.-% or about .gtoreq.95 wt.-% to about .ltoreq.99
wt.-%; or consist of a charge neutral metal amide compound
according to the invention.
[0362] According to another aspect of the present invention, there
is provided an organic light-emitting diode (OLED) comprising: a
substrate; a anode electrode formed on the substrate; a hole
injection layer comprising a metal amide according to the
invention, a hole transport layer, an emission layer, hole blocking
layer and a cathode electrode.
[0363] According to another aspect of the present invention, there
is provided an organic light-emitting diode (OLED) comprising: a
substrate; a anode electrode formed on the substrate; a hole
injection layer comprising a charge neutral metal amide according
to the invention, a hole transport layer, an emission layer, hole
blocking layer, electron transport layer, and a cathode
electrode.
[0364] According to another aspect of the present invention, there
is provided an organic light-emitting diode (OLED) comprising: a
substrate; a anode electrode formed on the substrate; a hole
injection layer comprising a charge neutral metal amide according
to the invention, a hole transport layer, an emission layer, hole
blocking layer, electron transport layer, an electron injection
layer, and a cathode electrode.
[0365] According to another aspect, there is provided an organic
light-emitting diode (OLED) comprising: at least one layer selected
from the group consisting of a hole injection layer, a hole
transport layer, an emission layer, a hole blocking layer, an
electron transport layer, exactly in that order between the anode
electrode and the cathode electrode.
[0366] According to various embodiments of the present invention,
there is provided an organic light-emitting diode (OLED) further
comprising an electron injection layer formed between the electron
transport layer and the cathode electrode.
[0367] According to various embodiments of the OLED of the present
invention, the OLED may not comprises an electron injection
layer.
[0368] According to various embodiments of the OLED of the present
invention, the OLED may not comprises an electron transport
layer.
[0369] According to various embodiments of the OLED of the present
invention, the OLED may not comprises an electron transport layer
and an electron injection layer.
[0370] According to another aspect of the present invention, there
is provided a method of manufacturing an organic light-emitting
diode (OLED), the method using: [0371] at least one deposition
source, preferably two deposition sources and more preferred at
least three deposition sources; and/or [0372] deposition via vacuum
thermal evaporation; and/or [0373] deposition via solution
processing, preferably the processing is selected from
spin-coating, printing, casting and/or slot-die coating.
Method of Manufacture
[0374] According to various embodiments of the present invention,
the method may further include forming on the anode electrode an
hole injection layer, an hole transport layer, an emission layer
and a cathode electrode, exactly in that order.
[0375] According to various embodiments of the present invention,
the method may further include forming on the anode electrode an
hole injection layer, an hole transport layer, an emission layer,
an electron transport layer, and a cathode electrode, exactly in
that order.
[0376] According to various embodiments of the present invention,
the method may further include forming on the anode electrode an
hole injection layer, an hole transport layer, hole blocking layer,
an emission layer, an electron transport layer, and a cathode
electrode, exactly in that order.
[0377] According to various embodiments of the present invention,
the method may further include the steps for forming an organic
light-emitting diode (OLED), wherein [0378] on a substrate a anode
electrode is formed, [0379] on the anode electrode an hole
injection layer is formed, [0380] on the hole injection layer an
hole transport layer is formed, [0381] optional on the hole
transport layer a hole blocking layer is formed, [0382] than an
emission layer is formed thereon, [0383] on the emission layer
optional an electron transport layer is formed, preferably an
electron transport layer stack, [0384] finally a cathode electrode
is formed thereon, [0385] optional an electron injection layer is
formed between the electron transport layer and the cathode
electrode.
[0386] The method of manufacturing the OLED may comprising the
steps: [0387] the hole injection layer according to the invention
is deposited on an anode layer, an optional hole transport layer is
deposited on the hole injection layer, an emission layer is
deposited on the hole transport layer, an optional hole blocking
layer is deposited on the emission layer, an optional electron
transport layer is deposited on the hole blocking layer, an
optional electron injection layer is deposited on the electron
transport layer and a cathode is deposited on the electron
injection layer, wherein the layers are arranged in that order and
sandwiched between the anode and the cathode.
[0388] However, according to one aspect the layers are deposited
the other way around, starting with the cathode, and sandwiched
between the cathode and the anode.
[0389] For example, starting with the cathode layer, optional
electron injection layer, electron transport layer, optional hole
blocking layer, emission layer, hole transport layer, hole
injection layer, anode electrode, exactly in this order.
[0390] The anode electrode and/or the cathode electrode can be
deposit on a substrate. Preferably the anode is deposit on a
substrate.
[0391] Additional aspects and/or advantages of the invention will
be set forth in part in the description which follows and, in part,
will be obvious from the description, or may be learned by practice
of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0392] These and/or other aspects and advantages of the present
invention will become apparent and more readily appreciated from
the following description of the exemplary embodiments, taken in
conjunction with the accompanying drawings, of which:
[0393] FIG. 1 is a schematic sectional view of an organic
light-emitting diode (OLED), according to an exemplary embodiment
of the present invention;
[0394] FIG. 2 is a schematic sectional view of an OLED, according
to an exemplary embodiment of the present invention.
[0395] FIG. 3 is a schematic sectional view of an OLED, according
to an exemplary embodiment of the present invention.
[0396] FIG. 4 is an overview of metal amides based on general
Formula Ia that can be used according to the invention.
[0397] FIG. 5 is an overview of metal amides that can be used
according to the invention with specific A.sup.1 and A.sup.2,
wherein A.sup.1 and A.sup.2 are SO.sub.2.
[0398] FIG. 6 is an overview of metal amides that can be used
according to the invention with specific A.sup.1 and A.sup.2,
wherein A.sup.1 and A.sup.2 are POR.sup.8.
[0399] FIG. 7 is an overview of metal amides that can be used
according to the invention with specific A.sup.1 and A.sup.2,
wherein A.sup.1 and A.sup.2 are CO.
[0400] FIG. 8 is an overview of metal amides that can be used
according to the invention with specific A.sup.1 and A.sup.2,
wherein A.sup.1 and A.sup.2 are selected different, wherein A.sup.1
is SO.sub.2 and A.sup.2 is POR.sup.8.
DETAILED DESCRIPTION
[0401] Reference will now be made in detail to the exemplary
embodiments of the present invention, examples of which are
illustrated in the accompanying drawings, wherein like reference
numerals refer to the like elements throughout. The exemplary
embodiments are described below, in order to explain the aspects of
the present invention, by referring to the figures.
[0402] Herein, when a first element is referred to as being formed
or disposed "on" a second element, the first element can be
disposed directly on the second element, or one or more other
elements may be disposed there between. When a first element is
referred to as being formed or disposed "directly on" a second
element, no other elements are disposed there between.
[0403] FIG. 1 is a schematic sectional view of an organic
light-emitting diode (OLED) 100, according to an exemplary
embodiment of the p