U.S. patent application number 10/743337 was filed with the patent office on 2004-12-02 for polymer, electroluminescent device, and light emitting device.
This patent application is currently assigned to SEMICONDUCTOR ENERGY LABORATORY, CO., LTD.. Invention is credited to Nomura, Ryoji, Seo, Satoshi, Takasu, Takako.
Application Number | 20040241494 10/743337 |
Document ID | / |
Family ID | 32677344 |
Filed Date | 2004-12-02 |
United States Patent
Application |
20040241494 |
Kind Code |
A1 |
Takasu, Takako ; et
al. |
December 2, 2004 |
Polymer, electroluminescent device, and light emitting device
Abstract
A novel electroluminescent polymer is represented by the general
formula (I). A is (a-1) or the like, and B or B' is either the
following (b-1) or (b-2). A film of the polymer represented by the
general formula (I) can be formed by electrolytic polymerization,
and further emits light in a different color by an electric field
when a substituent thereof is changed. Therefore, a light-emitting
device that is capable of multicolor displaying can be easily
obtained. 12
Inventors: |
Takasu, Takako; (Chigasaki,
JP) ; Seo, Satoshi; (Kawasaki, JP) ; Nomura,
Ryoji; (Yamato, JP) |
Correspondence
Address: |
NIXON PEABODY, LLP
401 9TH STREET, NW
SUITE 900
WASHINGTON
DC
20004-2128
US
|
Assignee: |
SEMICONDUCTOR ENERGY LABORATORY,
CO., LTD.
Atsugi-shi
JP
|
Family ID: |
32677344 |
Appl. No.: |
10/743337 |
Filed: |
December 23, 2003 |
Current U.S.
Class: |
428/690 ;
257/103; 257/40; 257/89; 313/504; 428/917 |
Current CPC
Class: |
C09K 2211/1425 20130101;
C08G 61/124 20130101; H01L 51/0006 20130101; H01L 51/5012 20130101;
H01L 27/3211 20130101; C09K 2211/1466 20130101; C09K 2211/1458
20130101; H01L 51/0052 20130101; C09K 11/06 20130101; H01L 51/0039
20130101; H01L 51/0036 20130101; H01L 51/0043 20130101; C09K
2211/14 20130101; Y10S 428/917 20130101; H01L 51/0094 20130101;
C09K 2211/1416 20130101; C08G 61/126 20130101 |
Class at
Publication: |
428/690 ;
428/917; 313/504; 257/040; 257/089; 257/103 |
International
Class: |
H05B 033/14; C09K
011/06 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 25, 2002 |
JP |
2002-375654 |
Claims
1. A polymer having the following general formula as a repeating
unit. 19[In the general formula (I), m and n are 1 or 2, A is any
of the following (a-1) to (a-20), and B and B' are identical or
different, and are either (b-1) or (b-2). 2021(R.sub.1 and R.sub.2
of (a-1) and R.sub.5 and R.sub.6 of (a-20) are identical or
different, and R.sub.1 to R.sub.6 are a hydrogen atom, a hologen
atom, or an organic substituent that may include an oxygen atom, a
sulfur atom or a nitrogen atom.) 22(R.sub.7 and R.sub.8 of (b-1)
and R.sub.9 and R.sub.10 of (b-2) are respectively identical or
different, and R.sub.7 to R.sub.10 are a hydrogen atom, a hologen
atom, or an organic substituent that may include an oxygen atom, a
sulfur atom or a nitrogen atom.)])
2. An electroluminescent device having a layer including a polymer
having a repeating unit represented by the following general
formula (I) between a pair of electrodes. 23[In the general formula
(I), m and n are 1 or 2, A is any of the following (a-1) to (a-20),
and B and B' are identical or different, and are either (b1) or
(b-2). 2425(R.sub.1 and R.sub.2 of (a-1) and R.sub.5 and R.sub.6 of
(a-20) are identical or different, and R.sub.1 to R.sub.6 are a
hydrogen atom, a hologen atom, or an organic substituent that may
include an oxygen atom, a sulfur atom or a nitrogen atom.)
26(R.sub.7 and R.sub.8 of (b-1) and R.sub.9 and R.sub.10 of (b-2)
are respectively identical or different, and R.sub.7 to R.sub.10
are a hydrogen atom, a hologen atom, or an organic substituent that
may include an oxygen atom, a sulfur atom or a nitrogen atom.)]
3. The light-emitting device according to claim 1 or 2, wherein the
layer including the polymer is a layer formed by electrolytic
polymerization.
4. A light-emitting device having a plurality of electroluminescent
devices, wherein each of the plurality of electroluminescent
devices has an opposed pair of electrodes and a layer including a
polymer, which is formed between the pair of electrodes, and
wherein the polymer is a compound having a repeating unit
represented by the following general formula (D). 27[In the general
formula (I), m and n are 1 or 2, A is any of the following (a-1) to
(a-20), and B and B' are identical or different, and are either
(b-1) or (b-2). 2829(R.sub.1 and R.sub.2 of (a-1) and R.sub.5 and
R.sub.6 of (a-20) are identical or different, and R.sub.1 to
R.sub.6 are a hydrogen atom, a hologen atom, or an organic
substituent that may include an oxygen atom, a sulfur atom or a
nitrogen atom.) 30(R.sub.7 and R.sub.8 of (b1)) and R.sub.9 and
R.sub.10 of (b-2) are respectively identical or different, and
R.sub.7 to R.sub.10 are a hydrogen atom, a hologen atom, or an
organic substituent that may include an oxygen atom, a sulfur atom
or a nitrogen atom.)]
5. The light-emitting device according to claim 4, wherein at least
one of the plurality of electroluminescent devices has the polymer
which is different from those of the other electroluminescent
devices.
6. A light-emitting device having: a substrate having an insulating
surface; a plurality of stripe-shaped first electrodes formed at
the insulating surface of the substrate; a layer including a
polymer, which is formed on each of the plurality of first
electrodes; and a plurality of stripe-shaped second electrodes
arranged to be orthogonal to the first electrodes, which are formed
on the plurality of layers including the polymer, wherein the
polymer is a compound having a repeating unit represented by the
following general formula (I). 31[In the general formula (I), m and
n are 1 or 2, A is any of the following (a-1) to (a-20), and B and
B' are identical or different, and are either (b-1) or (b-2).
3233(R.sub.1 and R.sub.2 of (a-1) and R.sub.5 and R.sub.6 of (a-20)
are identical or different, and R.sub.1 to R.sub.6 are a hydrogen
atom, a hologen atom, or an organic substituent that may include an
oxygen atom, a sulfur atom or a nitrogen atom.) 34(R.sub.7 and
R.sub.8 of (b-1) and R.sub.9 and R.sub.10 of (b-2) are respectively
identical or different, and R.sub.7 to R.sub.10 are a hydrogen
atom, a hologen atom, or an organic substituent that may include an
oxygen atom, a sulfur atom or a nitrogen atom.)]
7. The light-emitting device according to claim 6, wherein at least
one of the plurality of layers including the polymer has the
polymer which is different from those of the other layers including
the polymer.
8. The light-emitting device according to claim 6 or 7, wherein the
layers including the polymer are layers formed by electrolytic
polymerization.
9. A light-emitting device having: a substrate having an insulating
surface; a plurality of first electrodes formed at the insulating
surface of the substrate; a layer including a polymer, which is
formed on each of the plurality of first electrodes; and a second
electrode opposed to each of the plurality of first electrodes with
the plurality of layers including the polymer interposed in
between, wherein polymer is a compound having a repeating unit
represented by the following general formula (I). 35[In the general
formula (I), m and n are 1 or 2, A is any of the following (a-1) to
(a-20), and B and B' are identical or different, and are either
(b1) or (b-2). 3637(R.sub.1 and R.sub.2 of (a-1) and R.sub.5 and
R.sub.6 of (a-20) are identical or different, and R.sub.1 to
R.sub.6 are a hydrogen atom, a hologen atom, or an organic
substituent that may include an oxygen atom, a sulfur atom or a
nitrogen atom.) 38(R.sub.7 and R.sub.8 of (b-1) and R.sub.9 and
R.sub.10 of (b-2) are respectively identical or different, and
R.sub.7 to R.sub.10 are a hydrogen atom, a hologen atom, or an
organic substituent that may include an oxygen atom, a sulfur atom
or a nitrogen atom.)]
10. The light-emitting device according to claim 9, wherein at
least one of the plurality of layers including the polymer has the
included polymer which is different from those of the other layers
including the polymer.
11. A light-emitting device having a plurality of first to third
pixels that emit light in different colors from each other on a
substrate having an insulating surface, having: a plurality of
first electrodes; a layer including a polymer, which is formed on
each of the plurality of first electrodes; and a second electrode
opposed to the plurality of first electrodes, which is formed on
the layer including the polymer, wherein the first electrode is
provided with respect to each of the plurality of first to third
pixels, and the second electrode is provided in common with the
plurality of first to third pixels, and wherein the polymer is a
compound that has a repeating unit represented by the following
general formula (I), and the polymer of the layer including the
polymer is different from each other in the first to third pixels.
39[In the general formula (I), m and n are 1 or 2, A is any of the
following (a-1) to (a-20), and B and B' are identical or different,
and are either (b-1) or (b-2). 4041(R.sub.1 and R.sub.2 of (a-1)
and R.sub.5 and R.sub.6 of (a-20) are identical or different, and
R.sub.1 to R.sub.6 are a hydrogen atom, a hologen atom, or an
organic substituent that may include an oxygen atom, a sulfur atom
or a nitrogen atom.) 42(R.sub.7 and R.sub.8 of (b-1) and R.sub.9
and R.sub.10 of (b-2) are respectively identical or different, and
R.sub.7 to R.sub.10 are a hydrogen atom, a hologen atom, or an
organic substituent that may include an oxygen atom, a sulfur atom
or a nitrogen atom.)]
12. The light-emitting device according to any one of claims 9 to
11, wherein the layer including the polymer is a layer formed by
electrolytic polymerization.
13. The light-emitting device according to any one of claim 9 to
claim 11, has a plurality of data signal lines, the plurality of
scan signal lines, and a plurality of nonlinear elements connected
to one of the data signal lines and one of the scan signal lines,
wherein the plurality of first electrodes are respectively the
nonlinear elements.
14. The light-emitting device according to claim 13, wherein at
least a thin film transistor is used as the nonlinear elements.
Description
TECHNICAL FIELD
[0001] The present invention relates to an electroluminescent
polymer, in particular, relates to a polymer that can be formed by
electrolytic polymerization. In addition, the present invention an
electroluminescent device, a light-emitting device, and the like
using this polymer.
BACKGROUND ART
[0002] Since an electroluminescent element utilizing
electroluminescence of an organic compound has high visibility due
to being self-luminous, and has characteristics such as a low
driving voltage, the use as a light-emitting device has attracted
attention in various display devices.
[0003] Further, particularly in order to expand applications of the
aforementioned electroluminescent device, a multicolor application
such as an area-color or full-color display (hereinafter, referred
to as "a multicolor display device") is expected.
[0004] As methods of manufacturing a multicolor display device
using an electroluminescent device, the following methods are
known:
[0005] (1) A method of arranging EL materials emit in three primary
colors of red (R), green (G), blue (B) in a matrix (Refer to
Japanese Patent Laid-Open No. 57-157487, Japanese Patent Laid-Open
No. 58-147989, and Japanese Patent Laid-Open No. 3-214593, for
example.).
[0006] (2) A method of taking out three primary colors of RGB,
where an EL device that emits in white is combined with a color
filter (Refer to Japanese Patent Laid-Open No. 1-315988 and
Japanese Patent Laid-Open No. 2-273496, for example.).
[0007] (3) A method of converting into three primary colors of RGB,
where an EL device that emits in blue is combined with a
color-changing fluorescent film (Refer to Japanese Patent Laid-Open
No. 3-152897, for example).
[0008] (4) Further, a technique of making a conductive polymer
material that is used for an electroluminescent device into ink to
perform patterning of an EL material by an ink-jet method is known
as a method of manufacturing a multicolor display device without
forming a color filter or a fluorescence conversion filter required
for the aforementioned method (2) or (3) (Japanese Patent Laid-Open
No. 10-153967 and Japanese Patent Laid-Open No. 11-87062, for
example).
[0009] However, a group of .pi.-conjugated polymers that have been
researched long as conductive polymer materials in terms of
advantages such as stability have rigid main chains, and are often
insoluble or non-melted generally, which therefore cannot be used
in the aforementioned ink-jet method. Consequently, for the use in
the ink-jet method, a chemical contrivance (such as introduction of
a substituent) for solubilizing the conductive polymer materials is
required. However, in the case of being solubilized, there is a
problem such as lowering of a charge transport property or thermal
stability. Further, In the case of forming the conductive polymer
materials by the ink-jet method as a hole injection layer, advanced
techniques are required in order to prevent an electric leak
between respective pixels (crosstalk).
[0010] Besides, as another method of manufacturing an
electroluminescent device, electrochemical methods have been
proposed. As one of the electrochemical methods, electrolytic
polymerization is known, which is a method in which at least one of
an anode electrode and a cathode electrode opposed mutually is
dipped in an electrolytic solution (a polymerization solution)
including a material for forming a hole transport layer or an
electron transport layer, and then, the hole transport layer or the
electron transport layer is formed on the dipped anode electrode or
cathode electrode to be covered by applying a voltage between the
anode electrode and the cathode electrode. In manufacturing of an
electroluminescent device by electrolytic polymerization, a
conjugated polymer material that is superior in an injection of a
hole or an electron and a charge transport performance and also has
high stability thermally can be used (Refer to Japanese Patent
Laid-Open 9-976979, for example.). However, an organic material for
forming a light-emitting layer by an electrochemical method is not
mentioned at all in Japanese Patent Laid-Open 9-976979.
DISCLOSURE OF INVENTION
[0011] (Problem to be solved by the Invention)
[0012] Among methods of manufacturing a multicolor display device,
a method that is required to form a color filter or a fluorescence
conversion filter has a defect that an increase in cost is
unavoidable as a color filter for a conventional liquid crystal
display device. Further, although the case of using an inkjet
method does not have these defects, advanced techniques are
required, and the problem is that a polymer material to be used has
to be soluble.
[0013] In addition, while it is known that a conjugated polymer
material that is superior in a charge injection and transport
property and also has high stability thermally can be used as an
electron transport layer when an electrochemical method such as
electrolytic polymerization is used to form a hole transport layer
or the electron transport layer, forming a light-emitting layer by
electrolytic polymerization is not known. In other words, an
organic material for forming a light-emitting layer, which can be
synthesized by electrolytic polymerization, is not known.
[0014] It is an object of the present invention to resolve the
defect of related art to propose a group of polymers that can be
polymerized by electrolytic polymerization and emits various colors
by an electric field. In addition, it is an object of the present
invention to provide an electroluminescent device using this group
of polymers and a light-emitting device such as a multicolor
display device.
[0015] (Means for solving the Problem)
[0016] In order to solve the above-mentioned objects, a structure
of a polymer according to the present invention is characterized by
the following general formula (I) as a repeating unit. 3
[0017] [In the general formula (I), m and n are 1 or 2, A is any of
the following (a-1) to (a-20), and B and B' are identical or
different, and are either (b-1) or (b-2). 45
[0018] (R.sub.1 and R.sub.2 of (a-1) and R.sub.5 and R.sub.6 of
(a-20) are identical or different, and R.sub.1 to R.sub.6 are a
hydrogen atom, a hologen atom, or an organic substituent that may
include an oxygen atom, a sulfur atom or a nitrogen atom.) 6
[0019] (R.sub.7 and R.sub.8 of (b-1) and R.sub.9 and R.sub.10 of
(b-2) are respectively identical or different, and R.sub.7 to
R.sub.10 are a hydrogen atom, a hologen atom, or an organic
substituent that may include an oxygen atom, a sulfur atom or a
nitrogen atom.)]
[0020] The polymer shown by the aforementioned general formula (I)
is a compound designed with a focus mainly on a synthesis by
electrolytic polymerization being possible, and is a novel polymer
found by the inventors. Of course, a polymer according to the
present invention can not only be synthesized by electrolytic
polymerization but also by formed by a known synthesis method.
[0021] In addition, the novel polymer represented by the
aforementioned general formula (I) is made to emit light by an
electric field, and therefore can be used as a light-emitting layer
(a light emitter) of an electroluminescent device. Consequently, as
another invention, the present invention is related to an
electroluminescent device, which is characterized by having a layer
including a polymer that has a repeating unit represented by the
aforementioned general formula (I) between a pair of
electrodes.
[0022] In the electroluminescent device that has the aforementioned
structure, the layer including the polymer functions as a
light-emitting layer. Further, in order to take out light emitted
by the layer including the polymer, one or both of the pair of
electrode may be transparent or translucent.
[0023] The aforementioned electroluminescent device is
characterized also in that the layer including the polymer is
formed by electrolytic polymerization.
[0024] In addition, a light-emitting device can be formed by having
a plurality of electroluminescent devices as the above as
pixels.
[0025] In other words, a first light-emitting device according to
the present invention is a light-emitting device that has a
plurality of electroluminescent device, each of the plurality of
electroluminescent device has an opposed pair of electrodes and a
layer including a polymer formed between the pair of the
electrodes, and is characterized in that the polymer is a compound
that has a repeating unit represented by the aforementioned general
formula (I).
[0026] In addition, a layer including a polymer represented by the
aforementioned general formula (I) is appropriate as a
light-emitting layer a so-called passive electroluminescent
display.
[0027] In other words, a second light-emitting device according to
the present invention has a substrate that has an insulating
surface, a plurality of stripe-shaped first electrodes formed at
the insulating surface of the substrate, a layer including a
polymer, which is formed on each of the plurality of first
electrodes, and a plurality of stripe-shaped second electrodes
arranged to be orthogonal to the first electrodes, which are formed
on the plurality of layers including the polymer, and is
characterized in that the polymer is a compound that has a
repeating unit represented by the aforementioned general formula
(I).
[0028] Further, a third light-emitting device according to the
present invention has a substrate that has an insulating surface, a
plurality of first electrodes formed at the insulating surface of
the substrate, a layer including a polymer, which is formed on each
of the plurality of first electrodes, and a second electrode
opposed to each of the plurality of first electrodes with the
plurality of layers including the polymer interposed in between,
and is characterized in that the polymer is a compound that has a
repeating unit represented by the aforementioned general formula
(I).
[0029] In the aforementioned first to three display devices
according to the present invention, one of the plurality of layers
including the polymer is characterized in that the included polymer
is different from those of the other layers including the polymer.
This structure makes it possible to emit light in plural colors and
obtain a light-emitting display device that is capable of
multicolor displaying.
[0030] In a similar way, a fourth light-emitting device according
to the present invention is a device that becomes capable of
multicolor displaying, has a plurality of first to third pixels
that emit light in different colors from each other on a substrate
that has an insulating surface, has a plurality of first
electrodes, a layer including a polymer, which is formed on each of
the plurality of first electrodes, and a second electrode opposed
to the plurality of first electrodes, which is formed on the layer
including the polymer, and is characterized in that the first
electrode is provided with respect to each of the plurality of
first to third pixels, the second electrode is provided in common
with the plurality of first to third pixels, the polymer is a
compound that has a repeating unit represented by the
aforementioned general formula (I), and the polymer of the layer
including the polymer is different from each other in the first to
third pixels.
[0031] Further, an electroluminescent device according to the
present invention, which uses a novel polymer represented by the
aforementioned general formula (I), can be applied to an active
matrix light-emitting device. In this case, in the aforementioned
third and fourth light-emitting devices according to the present
invention, it is preferable to further include a data signal line,
a scan signal line, a nonlinear element connected to the data
signal line, the scan signal line, and the first electrode. It is
preferable that the nonlinear element is composed of a combination
of a thin film transistor and a capacitor connected to each other
or a combination of a thin film transistor and a parasitic
capacitor of the thin film transistor.
[0032] The layer including a polymer in the specification indicates
a layer that may include a component taken unavoidably for forming
the layer, various additives, or another component not to directly
relevant to a function of the layer or not to prevent a function of
the layer.
[0033] The light-emitting device in the specification indicates a
light-emitting device and an image display device, and the like
that use an organic light-emitting element. In addition, a module
that has a connecter such as an anisotropic conductive film (ACF:
Anisotropic Conductive Film), a flexible printed circuit (FPC:
Flexible printed circuit) a TAB (Tape Automated Bonding) tape, or a
TCP (Tape Carrier Package) attached, a module that has a printed
wiring board provided at the tip of a TAB tape or a TCP, and a
module that has an IC (integrated circuit) directly mounted by a
COG (Chip On Glass) method are all included in the light-emitting
device.
[0034] (Effect of the Invention)
[0035] The group of polymers represented by the general formula (I)
according to the present invention can be synthesized by
electrolytic polymerization. Since polymerization and formation of
a patterned film can be carried out at the same time in the
electrolytic polymerization, an electroluminescent device can be
easily made.
[0036] Consequently, it is possible to provide a light-emitting
device that is capable of multicolor displaying, which uses a layer
including a novel polymer according to the present invention for a
light-emitting layer.
BRIEF DESCRIPTION OF DRAWINGS
[0037] FIG. 1 is a diagram showing sectional structure of an
electroluminescent device.
[0038] FIG. 2 is a top view of a light-emitting device.
[0039] FIG. 3 is a top view and a sectional view of a
light-emitting device.
[0040] FIG. 4 is a specific example of electric appliances.
BEST MODE FOR CARRYING OUT THE INVENTION
[0041] First, specific examples of polymers represented by the
aforementioned general formula (I) will be described.
[0042] First, specific examples of the R.sub.1 to R.sub.6 of the A
in the general formula (I) will be described. The R.sub.1 to
R.sub.6 includes an aliphatic hydrocarbon group having 4 to 30
carbon atoms (such as an n-butyl group, an isobutyl group, a
sec-butyl group, a tert-butyl group, an n-pentyl group, an n-peptyl
group, a 2,6-dimethylheptyl group, 1-ethylpentyl group, an n-octyl
group, an n-decyl group, an undecyl group, or an n-heptadecyl
group) and a cyclohydrocarbon group having 4 to 10 carbon atoms
(such as a cyclobutyl group, a cyclopentyl group, a cyclohexyl
group, a cycloheptyl group, a cyclooctyl group, a cyclononyl group,
or a cyclodecyl group). Alternatively, an aromatic group such as a
phenyl group, a naphthyl group, an anthranil group, or a pyrenyl
group may be included.
[0043] These aromatic groups may be connected to a carbonyl group
with an alkylene group having 1 to 5 carbon atoms in between. In
addition, a group having a heterocycle may be included. Further,
the aforementioned substituents may be connected to a thiophene
moiety or pyrrol with an oxygen atom, a sulfur atom, a nitrogen
atom, or a silicon atom.
[0044] In addition, specific examples of the substituents R.sub.7
to R.sub.10 in B and B' of the general formula (I) include an
aliphatic hydrocarbon group having 4 to 30 carbon atoms (such as an
n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl
group, an n-pentyl group, an n-peptyl group, a 2,6-dimethylheptyl
group, 1-ethylpentyl group, an n-octyl group, an n-decyl group, an
undecyl group, or an n-heptadecyl group) and a cyclohydrocarbon
group having 4 to 10 carbon atoms (such as a cyclobutyl group, a
cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a
cyclooctyl group, a cyclononyl group, or a cyclodecyl group).
Alternatively, an aromatic group such as a phenyl group, a naphthyl
group, an anthranil group, or a pyrenyl group may be included.
[0045] These aromatic groups may be connected to a carbonyl group
with an alkylene group having 1 to 5 carbon atoms in between. In
addition, a group having a heterocycle may be included. Further,
the aforementioned substituents may be connected to a thiophene
moiety or pyrrol with an oxygen atom, a sulfur atom, a nitrogen
atom, or a silicon atom.
[0046] Next, a material for forming the polymer represented by the
general formula (I) will be described.
[0047] This polymer represented by the general formula (I) can be
obtained by cationic polymerization of a monomer represented by the
following general formula (II). A, B, and B' in the general formula
(II) are the same as A, B, and B' in the general formula (I),
respectively. 7
[0048] Next, preferable examples of monomers represented by the
aforementioned general formula (II) are shown below, of course,
which is not limited to these monomers in order to form a polymer
according to the present invention.
[0049] The following monomers shown by chemical formulas (1) to
(20) are specific examples in the case where B and B' are both the
thiophene represented by (b1). 8910
[0050] The following monomers shown by chemical formulas (21) to
(40) are specific examples in the case where B and B' are both the
pyrrol represented by (b-2). 111213
[0051] The following monomers shown by chemical formulas (41) to
(60) are specific examples in the case where one of B and B' is
(b-1) and the other is (b-2). 141516
[0052] A polymer according to the present invention, which has a
repeating unit represented by the aforementioned general formula
(I), can be synthesized and formed as a patterned film by using
electrolytic polymerization.
[0053] In the case of synthesis and deposition by electrolytic
polymerization, a polymer that has a repeating unit represented by
the aforementioned general formula (I) can be deposited on a
patterned electrode by dipping a substrate that has the patterned
electrode in a certain electrolytic solution and electrifying the
electrolytic solution. In other words, a patterned layer including
the polymer can be easily formed.
[0054] The patterned electrode in the specification denotes an
electrode pattern for determining the shape that emits light when
an electroluminescent device is made to emit light. For example, a
plurality of stripe-shaped electrode patterns are used in the case
of an electroluminescent device of a dot-matrix device, and a
specific segment electrode pattern is used in the case of a segment
device.
[0055] The certain electrolytic solution is a solution that has a
supporting electrolyte dissolved in solvent, a solvent that has a
high dielectric constant such as water, acetonitrile, or propylene
carbonate is preferable as the solvent to be used, and various
perchlorates, another salts, aids, or the like are used as the
supporting electrolyte. A monomer represented by the aforementioned
general formula (II), which is dissolved, is added to the
electrolytic solution like this to carry out electrolytic
polymerization.
[0056] Consequently, as a method of manufacturing an
electroluminescent device using a layer including a polymer
represented by the general formula (I), the aforementioned
electrolytic polymerization can be used. For example, a layer
including a polymer that has a repeating unit represented by the
aforementioned general formula (I) is formed by electrolytic
polymerization on a patterned electrode over a transparent
substrate comprising glass, synthetic resin, or the like. The layer
including the polymer that has the repeating unit represented by
the aforementioned general formula (I) may be formed on the
electrode and on the periphery thereof, and is not to be considered
always limited to only the upper surface of the electrode.
[0057] In the case of using electrolytic polymerization to
manufacture an electroluminescent device, what is necessary is to
include a process of forming a layer including a polymer
represented by the general formula (I) by electrolytic
polymerization as described above, another operation, and treatment
and the like may be included before and after the process of
electrolytic polymerization or in the process as long as the
electroluminescent device functions as it is.
[0058] In addition, as an electroluminescent device, a structure
such as a device that has a layer including a conductive polymer,
which is provided on an electrode, or a device that has a layer
including a conductive polymer, which is provided on an electrode,
and that has a layer comprising an inorganic compound between
another electrode paring with the electrode and the layer including
the conductive polymer, is exemplified. The order and number of
layers to be laminated and the thickness of each layer are not
particularly limited. Not only a light-emitting layer but also a
hole transport layer and an electro transport layer may be formed.
Alternatively, a charge injection layer may be provided in close
contact with the electrode in order to improve adhesiveness to the
electrode and improve a charge injection from the electrode.
Alternatively, a thin buffer layer may be provided at an interface
of a charge transport layer or a light-emitting layer in order to
improve an adhesiveness of the interface, prevent crystallization,
and the like.
[0059] Next, a method of manufacturing a light-emitting device that
is capable of multicolor displaying will be described.
[0060] For example, a plurality of patterned electrodes are formed
to correspond to a plurality of pixels over a transparent substrate
comprising glass, synthetic resin, or the like. By dipping this
substrate in an electrolytic solution including a monomer
represented by the aforementioned general formula (I) and
electrifying one of the electrodes, a layer including a first
polymer that has a repeating unit represented by the aforementioned
general formula (I) is formed on the electrified electrode as a
light-emitting layer.
[0061] Again, the substrate is infiltrated with an electrolytic
solution including a monomer that is different from the foregoing
one, and in accordance with the same process, a layer including a
second polymer represented by the aforementioned general formula
(I), which is different from the first polymer, is formed as a
light-emitting layer on an electrode that is different from the
electrode on which the first polymer is deposited. By repeating the
process like this, a plurality of pixels that emit light in
different colors are formed over the transparent substrate.
EMBODIMENTS
[0062] Hereinafter, the drawings are used to describe embodiments
of the present invention. The present invention is not to be
considered limited to the descriptions of the following
embodiments, unless depart from the scope thereof.
Embodiment 1
[0063] In the present embodiment, a method of manufacturing an
electroluminescent device will be described.
[0064] FIG. 1 shows a sectional structure of an electroluminescent
device.
[0065] On a glass substrate 100, an ITO film 101 of a thickness of
110 nm is deposited by sputtering, the ITO 101 is made into a dot
shape of 2 mm.times.2 mm by etching, and the glass substrate 101
that the patterned ITO electrode 101 is dipped in an electrolytic
solution that has a monomer represented by the following chemical
formula (61) and uses ammonium perchlorate as a supporting
electrolyte. 17
[0066] Then, by using the ITO electrode 101 as one electrode,
preparing a platinum wiring as an electrode paring therewith, and
applying a voltage therebetween, a light-emitting layer 102
including a polymer of the aforementioned chemical formula (61) is
electrochemically formed on the ITO electrode 101.
[0067] After this is washed with water, vacuum drying is performed.
Next, a cathode 103 is formed by depositing Ca and subsequently Al
to manufacture the electroluminescent device.
[0068] In FIG. 1, what is necessary is that either the first
electrode or the second electrode has transparency to visible
light. Further, the second electrode is necessarily a cathode in
the case where the first electrode is an anode while the second
electrode is necessarily an anode in the case where the first
electrode is a cathode.
Embodiment 2
[0069] In the present embodiment, a method of an active-matrix
multicolor light-emitting device will be described.
[0070] FIG. 2 is a partial view of an active matrix light-emitting
device.
[0071] On a transparent substrate 201 comprising glass, synthetic
resin, or the like, a plurality of patterned first electrodes 202
are formed, and an insulator partition 203 projecting above more
than the first electrodes 202 and surrounding a pixel portion is
formed.
[0072] Further, a data signal line 204, a scan signal line 205, and
a nonlinear element 206 are provided, and the nonlinear element is
connected to the first electrode through a contact 207. With this,
each pixel can be switched separately. The nonlinear element 206 is
composed of, typically, an electrically connected thin film
transistor and capacitor, a combination of a thin film transistor
and a parasitic capacitor of the thin film transistor, or the like.
In the same way as Embodiment 1, the substrate is dipped in an
electrolytic solution that has a monomer represented by the
aforementioned chemical formula (61) and uses ammonium perchlorate
as a supporting electrolyte.
[0073] Then, by using the data signal line 204 as one electrode
with a platinum wiring as a counter electrode and applying a
voltage to these electrode, a film including a polymer of the
aforementioned chemical formula (61) is electrochemically formed on
the electrode on the nonlinear element connected to the data signal
line 204.
[0074] Next, the glass substrate is dipped in an electrolytic
solution that has a monomer represented by the following chemical
formula (62) and uses ammonium perchlorate as a supporting
electrolyte. 18
[0075] Then, by using a data signal line 208 and applying a voltage
with a platinum wiring as a counter electrode, a film including a
polymer of the aforementioned chemical formula (62) is
electrochemically formed on the electrode on the nonlinear element
connected to the data signal line 208. Thereon, a shared second
electrode is formed all over the plurality of first electrodes.
[0076] In a light-emitting element of the light-emitting device of
FIG. 2, what is necessary is that either the first electrode or the
second electrode has transparency to visible light. Further, the
second electrode is necessarily a cathode in the case where the
first electrode is an anode while the second electrode is
necessarily an anode in the case where the first electrode is a
cathode.
Embodiment 3
[0077] In the present embodiment, a light-emitting device that has
an electroluminescent device according to the present invention in
a pixel portion will be described with reference to FIG. 3. FIG.
3(A) is a top view showing the light-emitting device and FIG. 3(B)
is a sectional view of FIG. 3(A) cut along A-A'.
[0078] In FIG. 3(A), as for rectangular areas indicated by dotted
lines, respectively, reference numeral 301 denotes a driver circuit
portion (a source side driver circuit), 302 is a pixel portion, and
303 is a driver circuit portion (a gate side driver circuit). In
addition, reference numeral 304 denotes a sealing substrate and 305
denotes a sealing agent. The inside 307 surrounded by the sealing
agent 305 is space (void).
[0079] Reference numeral 308 denotes a wiring for transmitting
signals to be input to the source side driver circuit 301 and the
gate side driver circuit 303, and receives a video signal, a clock
signal, a start signal, a reset signal, and the like from FPC
(Flexible Printed Circuit) 309 that serves as an external input
terminal. Though only the FPC is shown in the figure as the
reference numeral 308 here, a printed wiring board (PWB) may be
attached to the FPC. A light-emitting device in the specification
includes not only a light-emitting device body but also a state
where an FPC or a PWB is attached thereto.
[0080] Next, the sectional structure will be explained with
reference to FIG. 3(B).
[0081] In the source side driver circuit 301, a CMOS circuit is
formed of a combination of an n-channel TFT 323 and a p-channel TFT
324. The TFTs forming the driver circuit may also be formed of a
known CMOS circuit, PMOS circuit, or NMOS circuit. The gate side
driver circuit 303 is also similar to the source side driver
circuit 301. Although the present embodiment shows a driver
integrated type in which a driver circuit is formed over a
substrate, which is not always necessary, the driver circuit can be
formed not on the device substrate but at the outside thereof.
[0082] The pixel portion 302 is formed of a plurality of pixels,
each including a switching TFT 311, a current controlling TFT 312,
and a first electrode 313 connected to a drain thereof
electrically.
[0083] In addition, an insulator 314 is formed to cover an edge of
the first electrode 313. Here, the insulator 314 is formed of a
positive photosensitive acrylic resin. Besides, in order to obtain
a favorable coverage, the insulator 314 has a top portion or bottom
potion formed with a curved surface with a curvature. For example,
in the case of using positive photosensitive acrylic as a material
of the insulator 314, only the top portion of the insulator 314 can
easily have a curved surface with a curvature radius (0.2 .mu.m to
3 .mu.m). In addition, any of a photosensitive negative type that
becomes insoluble in an etchant by light and a positive type that
becomes soluble in an etchant by light can be used as the insulator
314.
[0084] On the first electrode 313, a light-emitting layer 416 and a
second electrode 317 are respectively formed. Here, as a material
that is used for the first electrode 313 functioning as an anode,
it is preferable to use a material that has a large work function.
For example, in addition to single layers such as an ITO (indium
tin oxide) film, an indium zinc oxide (IZO) film, a titanium
nitride film, a chromium film, a tungsten film, a Zn film, and a Pt
film, a laminate of a titanium nitride film and a film including
aluminum as its main component, a three-layer structure of a
titanium nitride film, a film including aluminum as its main
component, and a titanium nitride film, and the like can be used.
When a laminated structure is employed, the resistance as a wiring
is low, favorable ohmic contact can be taken, and it is possible to
function as an anode.
[0085] Further, the light-emitting layer 316 is formed by
electrolytic polymerization that is an electrochemical method. The
light-emitting layer 316 includes a polymer that has a repeating
unit of the aforementioned general formula (I) according to the
present invention. In addition, the light-emitting layer 316 may
include not only this polymer but also another material, which may
be a low molecular weight compound, a high molecular compound, or a
high molecular weight compound, or an inorganic compound. Further,
the light-emitting layer 316 may have a single layer or a laminate
of an organic compound of a high molecular weight compound or a low
molecular weight compound, or a layer including an inorganic
compound may be laminated in combination with these.
[0086] As a material that is used for the second electrode
(cathode) 317 formed on the light-emitting layer 316, a material
that has a small work function (Al, Ag, Li, or Ca, an alloy thereof
such as MgAg, MgIn, AlLi, or CaF.sub.2, or CaN) may be used. In the
case of transmitting light generated in the light-emitting layer
316 through the second electrode 317, it is preferable to use a
laminate of a thinned metal and a transparent conductive film (such
as ITO (an alloy of indium oxide and tin oxide), an alloy of indium
oxide and zinc oxide (In.sub.2O.sub.3--ZnO), or zinc oxide (ZnO))
film as the second electrode (cathode) 317.
[0087] Further, a structure is obtained by bonding the sealing
substrate 304 and the device substrate 310 with the sealing agent
305, where an electroluminescent device 318 is equipped in the
space 307 surrounded by the device substrate 301, the sealing
substrate 304, and the sealing agent 305. The space 307 is filled
with inert gas (such as nitrogen or argon), which may be filled
with the sealing agent 305 alternatively.
[0088] It is preferable to use epoxy resin for the sealing agent
305, and a material that allows no permeation of moisture or oxygen
to as much as possible is desirable. Further, as a material that is
used for the sealing substrate 304, a plastic substrate comprising
FRP (Fiberglass-Reinforced Plastics), PVF (polyvinylfluoride),
Mylar, polyester, acrylic, or the like can be used besides a glass
substrate and a quarts substrate.
[0089] In this way, the light-emitting device that has the
electroluminescent device according to the present invention can be
obtained.
Embodiment 4
[0090] In the present embodiment, various electric appliances
completed with the use of a light-emitting device that has an
electroluminescent device according to the present invention will
be described.
[0091] As electric appliances manufactured with the use of a
light-emitting device that has an electroluminescent device
according to the present invention, a video camera, a digital
camera, a goggle-type display (head mount display), a navigation
system, a sound reproduction device (such as an in-car audio system
or an audio set), a laptop personal computer, a game machine, a
personal digital assistance (such as a mobile computer, a mobile
phone, a portable game machine, or an electronic book), an image
reproduction device equipped with a recording medium (specifically,
a device equipped with a display device that can reproduce a
recording medium such as a digital versatile disc (DVD) and display
the image), and the like can be given. FIG. 4 shows specific
examples of these electric appliances.
[0092] FIG. 4(A) is a display device, which includes a frame body
2001, a support 2002, a display portion 2003, a speaker portion
2004, a video input terminal 2005, and the like. A light-emitting
device that has an electroluminescent device according to the
present invention is used for the display portion 2003 to
manufacture the display device. The display device includes all
devices for displaying information such as for a personal computer,
for receiving TV broad casting, and for displaying an
advertisement.
[0093] FIG. 4(B) is a laptop personal computer, which includes a
main body 2201, a frame body 2202, a display portion 2203, a
keyboard 2204, an external connection port 2205, a pointing mouse
2206, and the like. A light-emitting device that has an organic
light-emitting element according to the present invention is used
for the display portion 2203 to manufacture the laptop personal
computer.
[0094] FIG. 4(C) is a mobile computer, which includes a main body
2301, a display portion 2302, a switch 2303, an operation key 2304,
an infrared port 2305, and the like. A light-emitting device that
has an organic light-emitting element according to the present
invention is used for the display portion 2302 to manufacture the
mobile computer.
[0095] FIG. 4(D) is a portable image reproduction device equipped
with a recording medium (specifically, a DVD reproduction device),
which includes a main body 2401, a frame body 2402, a display
portion A 2403, a display portion B 2404, a recording medium (such
as DVD) reading portion 2405, an operation key 2406, a speaker
portion 2407, and the like. The display portion A 2403 is used
mainly for displaying image information while the display portion B
2404 is used mainly for displaying character information, and a
light-emitting device that has an organic light-emitting element
according to the present invention is used for these display
portion A 2403 and display portion B 2404 to manufacture the
portable image reproduction device equipped with the recording
medium. The image reproduction device equipped with the recording
medium further includes a home game machine and the like.
[0096] FIG. 4(E) is a goggle-type display (head mount display),
which includes a main body 2501, a display portion 2502, an arm
portion 2503, and the like. A light-emitting device that has an
organic light-emitting element according to the present invention
is used for the display portion 2502 to manufacture the goggle-type
display.
[0097] FIG. 4(F) is a video camera, which includes a main body
2601, a display portion 2602, a frame body 2603, an external
connection port 2604, a remote control receiving portion 2605, an
image receiving portion 2606, a battery 2607, a sound input portion
2608, an operation key 2609, an eye piece 2610, and the like. A
light-emitting device that has an organic light-emitting element
according to the present invention is used for the display portion
2602 to manufacture the video camera.
[0098] FIG. 4(G) is a mobile phone, which includes a main body
2701, a frame body 2702, a display portion 2703, a voice input
portion 2704, a voice output portion 2705, an operation key 2706,
an external connection port 2707, an antenna 2708, and the like. A
light-emitting device that has an organic light-emitting element
according to the present invention is used for the display portion
2703 to manufacture the mobile phone. The mobile phone can have
power consumption suppressed by displaying white characters on a
black background in the display portion 2703.
Industrial Applicability
[0099] Since a novel polymer according to the present invention is
easily formed by electrolytic polymerization as a patterned layer,
a full-color electroluminescent device can be manufactured with
higher productivity.
[0100] In addition, as described in Embodiment 4, a light-emitting
device according to the present invention is quite widely applied,
and this light-emitting device is applicable to electric appliances
in all fields.
* * * * *