U.S. patent application number 15/527045 was filed with the patent office on 2018-02-15 for organic light-emitting device and method of manufacturing the same, and display device.
This patent application is currently assigned to BOE TECHNOLOGY GROUP CO., LTD.. The applicant listed for this patent is BOE TECHNOLOGY GROUP CO., LTD.. Invention is credited to Leilei CHENG, Xinwei GAO, Daqing HU, Wenbin JIA, Rui PENG, Xinxin WANG.
Application Number | 20180047931 15/527045 |
Document ID | / |
Family ID | 55559090 |
Filed Date | 2018-02-15 |
United States Patent
Application |
20180047931 |
Kind Code |
A1 |
PENG; Rui ; et al. |
February 15, 2018 |
ORGANIC LIGHT-EMITTING DEVICE AND METHOD OF MANUFACTURING THE SAME,
AND DISPLAY DEVICE
Abstract
Disclosed are an organic light-emitting device and a method of
manufacturing the same, and a display device. The organic
light-emitting device includes: a first electrode layer, a second
electrode layer, and an organic light-emitting layer sandwiched
between the first electrode layer and the second electrode layer,
wherein the first electrode layer includes a first transparent
conductive layer, a nanostructured layer and a second transparent
conductive layer sequentially, and the second transparent
conductive layer is closer to the organic light-emitting layer than
the first transparent conductive layer. In the organic
light-emitting device, silver nanowires or carbon nanotubes can be
introduced between the two transparent conductive layers of the
first electrode layer, which facilitates the injection equilibrium
of electrons-holes, thereby improving the quantum efficiency.
Therefore, the organic light-emitting device has a high luminous
efficiency.
Inventors: |
PENG; Rui; (Beijing, CN)
; GAO; Xinwei; (Beijing, CN) ; CHENG; Leilei;
(Beijing, CN) ; JIA; Wenbin; (Beijing, CN)
; WANG; Xinxin; (Beijing, CN) ; HU; Daqing;
(Beijing, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BOE TECHNOLOGY GROUP CO., LTD. |
Beijing |
|
CN |
|
|
Assignee: |
BOE TECHNOLOGY GROUP CO.,
LTD.
Beijing
CN
|
Family ID: |
55559090 |
Appl. No.: |
15/527045 |
Filed: |
November 15, 2016 |
PCT Filed: |
November 15, 2016 |
PCT NO: |
PCT/CN2016/105950 |
371 Date: |
May 16, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01L 51/56 20130101;
H01L 51/5225 20130101; H01L 51/5203 20130101; H01L 51/5209
20130101; H01L 51/0048 20130101 |
International
Class: |
H01L 51/52 20060101
H01L051/52; H01L 51/56 20060101 H01L051/56 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 6, 2016 |
CN |
201610009483.0 |
Claims
1. An organic light-emitting device, comprising a first electrode
layer, a second electrode layer, and an organic light-emitting
layer sandwiched between the first electrode layer and the second
electrode layer, wherein the first electrode layer comprises a
first transparent conductive layer, a nanostructured layer and a
second transparent conductive layer sequentially, and the second
transparent conductive layer is closer to the organic
light-emitting layer than the first transparent conductive
layer.
2. The organic light-emitting device according to claim 1, wherein
a material for forming the nanostructured layer comprises silver
nanowires or carbon nanotubes.
3. The organic light-emitting device according to claim 1, wherein
the nanostructured layer has a periodically undulating
microstructure at an interface with the second transparent
conductive layer.
4. The organic light-emitting device according to claim 3, wherein
the first transparent conductive layer is formed on a substrate;
the nanostructured layer is formed on the first transparent
conductive layer; and the second transparent conductive layer, the
organic light-emitting layer and the second electrode layer are
sequentially formed on the nanostructured layer in an equal
thickness manner.
5. The organic light-emitting device according to claim 3, wherein
the periodically undulating microstructure is a wavy structure.
6. The organic light-emitting device according to claim 3, wherein
the microstructure is formed by rolling a rod-like roller in a
predetermined direction on the nanostructured layer before being
cured.
7. The organic light-emitting device according to claim 1, wherein
the second transparent conductive layer has a thickness less than
that of the first transparent conductive layer.
8. A method of manufacturing an organic light-emitting device,
comprising: forming a first transparent conductive layer on a
substrate; forming a nanostructured layer on the first transparent
conductive layer; forming a second transparent conductive layer on
the nanostructured layer; preparing an organic light-emitting layer
on the second transparent conductive layer; and forming a second
electrode layer on the organic light-emitting layer.
9. The method according to claim 8, wherein a material for forming
the nanostructured layer comprises silver nanowires or carbon
nanotubes.
10. The method according to claim 9, wherein the forming a
nanostructured layer on the first transparent conductive layer
comprises: coating the first transparent conductive layer with a
suspension solution of silver nanowires or a dispersion of carbon
nanotubes; rolling on the coated first transparent conductive layer
in a predetermined direction using a rod-like roller to form a
nanostructured layer having a periodically undulating
microstructure at the surface; and curing the nanostructured
layer.
11. The method according to claim 10, wherein the nanostructured
layer is formed in a nitrogen atmosphere and/or under vacuum.
12. The method according to claim 11, wherein if the material for
forming the nanostructured layer comprises silver nanowires, the
method further comprises: increasing the adhesion between the
nanostructured layer and the first transparent conductive layer in
a photon sintering manner after forming the nanostructured layer on
the first transparent conductive layer.
13. A display device, comprising the organic light-emitting device
according to claim 1.
14. The organic light-emitting device according to claim 2, wherein
the second transparent conductive layer has a thickness less than
that of the first transparent conductive layer.
15. The organic light-emitting device according to claim 3, wherein
the second transparent conductive layer has a thickness less than
that of the first transparent conductive layer.
16. The organic light-emitting device according to claim 4, wherein
the second transparent conductive layer has a thickness less than
that of the first transparent conductive layer.
17. The organic light-emitting device according to claim 5, wherein
the second transparent conductive layer has a thickness less than
that of the first transparent conductive layer.
18. The organic light-emitting device according to claim 6, wherein
the second transparent conductive layer has a thickness less than
that of the first transparent conductive layer.
Description
TECHNICAL FIELD
[0001] Embodiments of the present disclosure relate to an organic
light-emitting device and a method of manufacturing the same, and a
display device.
BACKGROUND
[0002] Since the birth of Organic Light-Emitting Diode (OLED), it
has been widely used in the display and lighting industry owing to
its advantages such as self-luminescence, light weight, high color
gamut and low energy consumption. However, the development of OLED
is currently limited by many conditions. For example, ITO (indium
tin oxide) is currently used as a transparent anode, the bottom
emitting traditional organic light-emitting diode can achieve an
external quantum efficiency up to only 30%, i.e., the luminous
efficiency is low.
SUMMARY
[0003] Embodiments of the present invention provide an organic
light-emitting device and a method of manufacturing the same, and a
display device, which can achieve a high luminous efficiency.
[0004] In a first aspect, embodiments of the present invention
provide an organic light-emitting device, comprising a first
electrode layer, a second electrode layer, and an organic
light-emitting layer sandwiched between the first electrode layer
and the second electrode layer, wherein the first electrode layer
comprises a first transparent conductive layer, a nanostructured
layer and a second transparent conductive layer sequentially, and
the second transparent conductive layer is closer to the organic
light-emitting layer than the first transparent conductive
layer.
[0005] Optionally, a material for forming the nanostructured layer
comprises silver nanowires or carbon nanotubes.
[0006] Optionally, the nanostructured layer has a periodically
undulating microstructure at an interface with the second
transparent conductive layer.
[0007] Optionally, the first transparent conductive layer is formed
on a substrate; the nanostructured layer is formed on the first
transparent conductive layer; and the second transparent conductive
layer, the organic light-emitting layer and the second electrode
layer are sequentially formed on the nanostructured layer in an
equal thickness manner.
[0008] Optionally, the periodically undulating microstructure is a
wavy structure.
[0009] Optionally, the microstructure is formed by rolling a
rod-like roller in a predetermined direction on the nanostructured
layer before being cured.
[0010] Optionally, the second transparent conductive layer has a
thickness less than that of the first transparent conductive
layer.
[0011] In a second aspect, an embodiment of the present invention
further provides a method of manufacturing an organic light
emitting device, comprising:
[0012] forming a first transparent conductive layer on the
substrate;
[0013] forming a nanostructured layer on the first transparent
conductive layer;
[0014] forming a second transparent conductive layer on the
nanostructured layer;
[0015] preparing an organic light-emitting layer on the second
transparent conductive layer; and
[0016] forming a second electrode layer on the organic
light-emitting layer.
[0017] Optionally, the material for forming the nanostructured
layer comprises silver nanowires or carbon nanotubes.
[0018] Optionally, the forming a nanostructured layer on the first
transparent conductive layer comprises:
[0019] coating the first transparent conductive layer with a
suspension solution of silver nanowires or a dispersion of carbon
nanotubes;
[0020] rolling on the coated first transparent conductive layer in
a predetermined direction using a rod-like roller to form a
nanostructured layer having a periodically undulating
microstructure at the surface; and
[0021] curing the nanostructured layer.
[0022] Optionally, the nanostructured layer is formed in a nitrogen
atmosphere and/or under vacuum.
[0023] Optionally, if the material for forming the nanostructured
layer comprises silver nanowires, the method may further
comprise:
[0024] increasing the adhesion between the nanostructured layer and
the first transparent conductive layer in a photon sintering manner
after forming the nanostructured layer on the first transparent
conductive layer.
[0025] In a third aspect, embodiments of the present invention
provide a display device, comprising any one of the organic
light-emitting devices described above.
[0026] As can be seen from the above technical solutions, in the
organic light-emitting device according to the embodiments of the
present invention, the design of introducing silver nanowires or
carbon nanotubes between the two transparent conductive layers of
the first electrode layer facilitates injection equilibrium of
electrons-holes, thereby improving the quantum efficiency.
Therefore, the organic light-emitting devices according to
embodiments of the present invention can have a high luminous
efficiency.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] In order to more clearly illustrate the technical solutions
of the embodiments of the present invention, the drawings of the
embodiments are briefly described below. Apparently, the drawings
described below relate to only some embodiments of the present
invention and thus are not limitative on the present invention.
[0028] FIG. 1 is a structural schematic view of an organic
light-emitting device according to an embodiment of the present
invention.
[0029] FIGS. 2 to 4 show a flow chart of a method of manufacturing
an organic light-emitting device according to an embodiment of the
present invention.
DETAILED DESCRIPTION
[0030] To make clearer the objects, technical solutions and
advantages of the embodiments of the present invention, a clear and
full description of the technical solutions of the embodiments of
the present invention will be made with reference to the
accompanying drawings. Apparently, the embodiments described are
just part rather than all of the embodiments of the present
invention. Based on the embodiments of the present invention as
described, all the other embodiments obtained by a person of
ordinary skill in the art, without any creative labor, fall within
the protection scope of the present invention.
[0031] In a first aspect, embodiments of the present invention
provide an organic light-emitting device, comprising a first
electrode layer, a second electrode layer, and an organic
light-emitting layer sandwiched between the first electrode layer
and the second electrode layer, wherein the first electrode layer
comprises a first transparent conductive layer, a nanostructured
layer and a second transparent conductive layer sequentially, and
the second transparent conductive layer is closer to the organic
light-emitting layer than the first transparent conductive
layer.
[0032] It should be noted that the organic light emitting device of
the embodiment of the present invention can be provided with
reference to a structure of an organic light emitting diode (OLED)
in the prior art, and the present invention is not limited thereto.
Specifically, indium tin oxide (ITO) may be used to form the first
transparent conductive layer and the second transparent conductive
layer, and the second electrode layer may be formed of a metal or a
conductive resin. It is to be understood that the first electrode
layer and the second electrode layer respectively form two
electrodes of the organic light emitting device and supply a
driving voltage or driving current to the organic light emitting
layer for emitting light.
[0033] In the organic light emitting device provided by the
embodiment of the present invention, a nanostructure layer is
introduced between two transparent conductive layers of one of the
electrode layers, and such a design contributes to injection
equilibrium of electrons-holes, thereby improving the quantum
efficiency. Due to the high quantum efficiency, the organic light
emitting device provided by the embodiment of the present invention
can have a high luminous efficiency.
[0034] In a second aspect, embodiments of the present invention
provide a method of manufacturing an organic light-emitting device,
which can be used for making the organic light-emitting device as
described in the first aspect and comprises:
[0035] forming a first transparent conductive layer on a
substrate;
[0036] forming a nanostructured layer on the first transparent
conductive layer;
[0037] forming a second transparent conductive layer on the
nanostructured layer;
[0038] preparing an organic light-emitting layer on the second
transparent conductive layer; and
[0039] forming a second electrode layer on the organic
light-emitting layer.
[0040] Upon specific implementation, there may be a variety of
specific structures of the above-mentioned organic light-emitting
devices, and the corresponding preparation methods are also
different. The following will be illustrated with reference to the
accompanying drawings.
[0041] Reference may be made to FIG. 1 for a particular structure
of an organic light-emitting device according to the embodiment of
the present invention, which comprises: [0042] a substrate 100,
[0043] a first electrode layer 200 formed on the substrate 100 (the
first electrode layer 200 specifically including a first
transparent conductive layer 210, a nanostructured layer 220, and a
second transparent conductive layer 230), [0044] an organic
light-emitting layer 300 further formed on the second transparent
conductive layer 230, and [0045] a second electrode layer 400
further formed on the organic light-emitting layer 300; wherein the
material of the nanostructured layer 220 may include silver
nanowires or carbon nanotubes; both the upper surface of the
nanostructured layer 220 and the lower surface of the second
transparent conductive layer 230 have a wavy microstructure (i.e.,
there is a wavy microstructure at their interface); both the second
transparent conductive layer 230 and the organic light-emitting
layer 300 have a layer structure of a uniform thickness so that the
upper surface of the second transparent conductive layer 230 and
the upper surface of the organic light-emitting layer 300 have a
shape consistent with the upper surface of the nanostructured layer
220, i.e., they both have a wavy microstructure. Furthermore, the
second transparent conductive layer 230 has a thickness d2 that is
less than the thickness d1 of the first transparent conductive
layer 210.
[0046] In the embodiment of the present invention, the design of
introducing a nanostructured layer 220 between the two transparent
conductive layers 210 and 230 of the first electrode layer 200
facilitates injection equilibrium of electrons-holes, thereby
improving the quantum efficiency. As a consequence, the organic
light-emitting device according to the embodiment of the present
invention can have a high luminous efficiency.
[0047] Meanwhile, in the embodiment of the present invention, the
nanostructured layer 220 has a wavy microstructure at the interface
with the second transparent conductive layer 230. Moreover, because
the second transparent conductive layer 230 and the organic
light-emitting layer 300 are both layer structures with a uniform
thickness, the shapes of the upper surfaces of the second
transparent conductive layer 230 and the organic light-emitting
layer 300 are consistent with that of the upper surface of the
nanostructured layer 220, i.e., both of them also have a wavy
microstructure. Such a design can reduce the waveguide effect and
the microcavity effect, thereby improving the light out-coupling
efficiency of the organic light-emitting device and further
improving the luminous efficiency of the organic light-emitting
device. It is to be understood that, upon specific implementation,
the waveguide effect and the microcavity effect can be reduced to a
certain degree if the upper surface (i.e., the interface with the
layer structure thereabove) of any one or two of the nanostructured
layer 220, the second transparent conductive layer 230 and the
organic light-emitting layer 300 has a microstructure, and such
technical solutions should also fall within the protection scope of
the present invention. Further, even if the upper surfaces of the
nanostructured layer 220, the second transparent conductive layer
230, and the organic light-emitting layer 300 are flat, the
corresponding technical solutions can still improve the luminous
efficiency as compared with the prior art, and should fall within
the protection scope of the present invention. It is to be
understood that although the embodiments of the present invention
are illustrated with a periodically undulating microstructure which
is a wavy microstructure, the periodically undulating
microstructure in actual applications may also be in other forms as
long as it is periodically undulating. The corresponding technical
solutions should achieve similar effects and thus should also fall
within the protection scope of the present invention.
[0048] Besides, in the embodiment of the present invention, a first
transparent conductive layer 210 is formed on a substrate 100, and
then a nanostructured layer 220, a second transparent conductive
layer 230, an organic light-emitting layer 300, and a second
electrode layer 400 are sequentially formed on the transparent
conductive layer 210. Such a design results in convenience for
fabrication. Apparently, other structural designs may also be used
in practical applications, for example, a second electrode layer
400 is formed on a substrate 100 followed by forming an organic
light-emitting layer 300, a second transparent conductive layer
230, a nanostructured layer 220, and a first transparent conductive
layer 210 sequentially on the second electrode layer 400. Such a
technical solution can also improve the quantum efficiency. The
structure in FIG. 1 is not to be construed as limiting the
protection scope of the present invention.
[0049] Upon specific implementation, the microstructure described
above may be formed by rolling a rod-like roll in a predetermined
direction onto the nanostructured layer prior to curing. On the one
hand, the production is less difficult; on the other hand, the
nanostructured layer made has a micro-structure that is evenly
distributed, thereby improving the quantum efficiency. Apparently,
the microstructures described above may also be microstructures
made in other ways in particular embodiments.
[0050] In the embodiments of the present invention, the thickness
of the second transparent conductive layer is set smaller than the
thickness of the first transparent conductive layer, which can
further improve the light out-coupling efficiency of the organic
light-emitting device. In particular embodiments, the first
transparent conductive layer herein may have a thickness of from
about 100 to about 200 nm and the second transparent conductive
layer may have a thickness of from about 50 to about 100 nm.
[0051] In particular embodiments, the materials of the first
transparent conductive layer and the second transparent conductive
layer herein may be transparent electrode materials such as ITO and
the like. The nanostructured layer may be formed of silver
nanowires or carbon nanotubes.
[0052] In particular embodiments, the above-mentioned manufacturing
method may specifically include the following steps if it is used
for producing the organic light-emitting device described
above:
[0053] Step 1: a transparent electrode material is deposited on a
substrate to form a first transparent conductive layer.
[0054] In particular embodiments, an ITO material layer of about
100 to 200 nm can be formed on the substrate by a magnetron
sputtering process as the first transparent conductive layer.
Reference may be made to FIG. 2 for the structure obtained after
step S1, which includes a substrate 100 and a first transparent
conductive layer 210 formed on the substrate 100.
[0055] Step S2: a nanostructured layer is formed on the first
transparent conductive layer, wherein the material for forming the
nanostructured layer comprises silver nanowires or carbon
nanotubes.
[0056] In particular embodiments, a suspension solution (which may
be a about 0.5% isopropanol suspension) of silver nanowires or a
dispersion (about 0.1-0.5 wt % dispersion in an ethanol solution)
of carbon nanotubes may be scraped onto the surface of the first
transparent conductive layer 210, which is then rolled with a
rod-like roll in one direction. The rolling pressure may be 0.1-0.3
MPa, which can result in a number of periodically undulating
microstructures.
[0057] In particular embodiments, in order to make the surface of
the nanostructure layer robust, a curing step may be performed
after forming silver nanowires. Specifically, the curing step may
include a film-forming solidification process and a hardening
process. The film-forming solidification process can be placing the
substrate on which silver nanowires have been formed in a vacuum
oven for solidification wherein the vacuum for solidification can
be about 100-133 Pa, and the temperature can be room temperature to
about 60.degree. C.; the hardening process can be baking the
solidified structure at about 100.degree. C. to about 200.degree.
C. for about 30 min.
[0058] In particular embodiments, these processes may be carried
out in a nitrogen atmosphere or under vacuum, and different
operations can be carried out in a nitrogen atmosphere and under
vacuum to prevent the silver nanowires from being oxidized in the
air.
[0059] Reference may be made to FIG. 3 for the structure obtained
after step S2, which further includes a nanostructure layer 220
having a microstructure on the upper surface as compared to FIG.
2.
[0060] In step S3, the adhesion between the nanostructure layer and
the first transparent conductive layer is increased by photon
sintering.
[0061] In particular embodiments, the exposure time for photonic
sintering can be controlled as from about 500 to 2000 .mu.s.
[0062] Step S3 can enhance the adhesion between the nanostructured
layer and the first transparent conductive layer. Of course, in
particular embodiments, step S3 is not a necessary step. In
particular, if the material for forming the nanostructure layer is
a carbon nanotube dispersion, it is not necessary to perform step
S3 here.
[0063] In step S4, a transparent electrode material is deposited on
the nanostructured layer to form a second transparent conductive
layer.
[0064] In particular embodiments, an ITO material layer of about
50-100 nm may be deposited on the nanostructure layer as the second
transparent conductive layer. During the deposition process, the
thickness of the resulting second transparent conductive layer at
each position can be made equal by reasonable controlling. This
enables the upper surface of the second transparent conductive
layer to also have a microstructure.
[0065] Reference may be made to FIG. 4 for the structure obtained
after step S4, which further includes a second transparent
conductive layer 230 as compared to FIG. 3.
[0066] In step S5, an organic light-emitting layer and a second
electrode layer are formed sequentially on the second transparent
conductive layer.
[0067] Reference may be made to FIG. 1 for the structure obtained
after step S5, which further comprises an organic light-emitting
layer 300 and a second electrode layer 400 as compared to FIG.
4.
[0068] In a third aspect, embodiments of the present invention
further provide a display device, comprising any organic
light-emitting device as described in the first aspect. It shall be
noted that the display device may be any product or component
having a display function, such as a display panel, electronic
paper, a mobile phone, a tablet, a TV set, a monitor, a laptop, a
digital photo frame, a navigator, or the like.
[0069] Unless otherwise defined, the technical terms or scientific
terms used herein shall have general meanings interpreted by a
person of ordinary skill in the art to which the present invention
pertains. The words "first", "second" and the like used in the
description and claims of the present application do not denote any
order, quantity or importance, but are merely used to distinguish
different components. Likewise, the words "one", "a", "an" and the
like do not denote any limitation on number, but represent the
presence of at least one. The words "comprise", "include" and the
like mean that the elements or objects preceding the words cover
the elements or objects listed after the words and their
equivalents, without excluding other elements or objects. The words
"upper", "lower", "left", "right" and the like are used only to
represent the relative positional relationship, and the relative
positional relationship may be changed accordingly if the absolute
position of the object described changes.
[0070] It shall be noted that the technical features in the
embodiments can be used in any combination if they are not
contradictory.
[0071] The above are merely exemplary embodiments of the present
invention, and are not intended to limit the protection scope of
the present invention, which is yet determined by the appended
claims.
[0072] The present application claims the priority of the Chinese
patent application No. 201610009483.0 submitted on Jan. 6, 2016,
which is incorporated herein by reference as part of the present
application.
* * * * *