U.S. patent application number 13/951158 was filed with the patent office on 2013-11-28 for organic light-emitting element, method for manufacturing the organic light-emitting element, apparatus for manufacturing the organic light-emitting element, and organic light-emitting device using the organic light-emitting element.
This patent application is currently assigned to HITACHI, Ltd.. The applicant listed for this patent is HITACHI, Ltd.. Invention is credited to Sukekazu ARATANI, Kotaro ARAYA, Shingo ISHIHARA, Hiroyuki KAGAWA, Kazuhito MASUDA, Shintaro TAKEDA.
Application Number | 20130313537 13/951158 |
Document ID | / |
Family ID | 41434083 |
Filed Date | 2013-11-28 |
United States Patent
Application |
20130313537 |
Kind Code |
A1 |
ARATANI; Sukekazu ; et
al. |
November 28, 2013 |
Organic Light-Emitting Element, Method for Manufacturing the
Organic Light-Emitting Element, Apparatus for Manufacturing the
Organic Light-Emitting Element, and Organic Light-Emitting Device
Using the Organic Light-Emitting Element
Abstract
An organic light-emitting display device is provided that has
prolonged service life, lowered wiring resistance that can lower
power consumption, and that is easy to manufacture. In a first
embodiment, a moisture capturing layer is provided between an upper
electrode and a lower electrode. A second embodiment includes a
metal substrate, an organic light-emitting element on the substrate
and an upper transparent electrode connected to the substrate
through a contact hole. In a third embodiment, a method is provided
for forming a first organic compound including a light-emitting
layer, heating the first organic compound in vacuo, and forming a
second organic compound.
Inventors: |
ARATANI; Sukekazu;
(Hitachiota, JP) ; MASUDA; Kazuhito; (Hitachi,
JP) ; ARAYA; Kotaro; (Hitachiota, JP) ;
KAGAWA; Hiroyuki; (Hitachinaka, JP) ; TAKEDA;
Shintaro; (Hitachi, JP) ; ISHIHARA; Shingo;
(Mito, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
HITACHI, Ltd. |
Tokyo |
|
JP |
|
|
Assignee: |
HITACHI, Ltd.
Tokyo
JP
|
Family ID: |
41434083 |
Appl. No.: |
13/951158 |
Filed: |
July 25, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12999859 |
Dec 17, 2010 |
8536611 |
|
|
PCT/JP2009/060867 |
Jun 15, 2009 |
|
|
|
13951158 |
|
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Current U.S.
Class: |
257/40 |
Current CPC
Class: |
H01L 51/0059 20130101;
H01L 51/0085 20130101; H01L 51/0087 20130101; H01L 2251/5346
20130101; H01L 51/5096 20130101; H05B 33/22 20130101; H01L 51/5203
20130101; H01L 51/50 20130101; H01L 2251/5315 20130101; C09K
2211/185 20130101; H01L 51/52 20130101; H01L 51/5259 20130101; H01L
51/5012 20130101; H01L 51/56 20130101; H01L 51/5234 20130101 |
Class at
Publication: |
257/40 |
International
Class: |
H01L 51/52 20060101
H01L051/52 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 17, 2008 |
JP |
2008-157330 |
Jun 25, 2008 |
JP |
2008-165213 |
Jul 3, 2008 |
JP |
2008 174074 |
Claims
1. An organic light-emitting display device comprising: a
light-emitting layer; an upper electrode and a lower electrode
sandwiching the light-emitting layer, wherein one of the upper and
lower electrodes comprises a transparent electrode transmitting a
light emitted from the light-emitting layer and the other electrode
of the upper and lower electrodes comprises a reflective electrode
which reflects a light emitted from the light-emitting layer; and a
moisture capturing layer disposed between the upper electrode and
the lower electrode.
2. The organic light-emitting display device according to claim 1,
wherein the moisture capturing layer is disposed between the
light-emitting layer and the upper electrode.
3. The organic light-emitting display device according to claim 2,
wherein a blocking layer and an electron transporting layer are
disposed between the upper and lower electrodes, and the moisture
capturing layer is disposed between the blocking layer and the
electron transporting layer.
4. The organic light-emitting display device according to claim 2,
wherein the moisture capturing layer is disposed adjacently to the
light-emitting layer, and the light-emitting layer is doped with a
dopant at a lower concentration on a side adjacent to the moisture
capturing layer than on the opposite side.
5. The organic light-emitting display device according to claim 2,
wherein the moisture capturing layer is disposed adjacently to the
light-emitting layer, and the light-emitting layer has a
light-emitting region separated from the moisture capturing
layer.
6. The organic light-emitting display device according to claim 2,
wherein a blocking layer is disposed between the upper and lower
electrodes, the moisture capturing layer is disposed between the
light-emitting layer and the blocking layer, and the light-emitting
layer contains an electron transporting material.
7. The organic light-emitting display device according to claim 2,
wherein a bank surface-treated to be water-repellent is disposed
between the upper and lower electrodes.
8. The organic light-emitting display device according to claim 2,
wherein a light-emitting dopant dispersed in the light-emitting
layer has an asymmetric structure.
9. The organic light-emitting display device according to claim 2,
wherein at least one of the materials, that constitute the
light-emitting layer, has an asymmetric structure.
10. The organic light-emitting display device according to claim 2,
wherein the light-emitting layer contains a high-molecular-weight
material.
11. The organic light-emitting display device according to claim 2,
wherein a thin, liquid-repellent film is disposed between adjacent
pixels.
12. The organic light-emitting display device according to claim 1,
wherein the moisture capturing layer contains a metal and/or metal
oxide.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation application of U.S.
application Ser. No. 12/999,859, filed Dec. 17, 2010 and the
subject matter of which is incorporated by reference herein and
which application is a 371 National Stage application of
PCT/JP2009/060867, filed Jun. 15, 2009.
FIELD OF THE INVENTION
[0002] The present invention relates to an organic light-emitting
element, a method for manufacturing the organic light-emitting
element, an apparatus for manufacturing the organic light-emitting
element, and an organic light-emitting device using the organic
light-emitting element.
BACKGROUND OF THE INVENTION
[0003] Recently, organic light-emitting display devices have been
attracting attention as plane type display devices of the next
generation. They have excellent characteristics of natural light,
wide view angles, fast response and so on.
[0004] Generally, an organic light-emitting element has a structure
with a glass substrate which supports an organic light
electroluminescent (EL) layer composed of a transparent electrode,
e.g., of ITO, hole transporting layer, light-emitting layer,
electron transporting layer and so on, and reflective electrode of
low work function, where light emitted from the light-emitting
layer is emitted from the back side of the substrate after passing
through the electrode.
[0005] These organic light-emitting display devices can now have
high efficiency and prolonged service life, when each of the
organic layers is formed by vacuum deposition. R. Meerheim et al,
for example, discloses that vacuum deposition can manufacture an
organic red-color-emitting element having a brightness half period
of 1,500,000 hours or more, when its initial brightness is 500
cd/m.sup.2 (Non-patent Document 1). The other methods for
manufacturing organic light-emitting display devices include wet
processes, e.g., spin coating and ink jetting for forming organic
layers. An organic light-emitting display device manufactured by a
wet process has a shorter service life and lower efficiency than an
organic light-emitting element manufactured by vacuum deposition.
Non-patent Document 2 discloses that an organic red-color-emitting
element manufactured by spin coating using polymers has a service
life of about 100,000 hours when its initial brightness is 500
cd/m.sup.2. The service life is about one-tenth that disclosed in
Non-patent Document 1.
[0006] Recently, use of low-molecular-weight materials for forming
films by embrocation has been studied. For example, Non-patent
Document 3 discloses that an organic red-color-emitting element has
a service life of at least 25,000 hours when its initial brightness
is 500 cd/m.sup.2. The element has a shorter service life than the
one manufactured by vacuum deposition using a low-molecular-weight
material, disclosed in Patent Document 1. As discussed above, an
element with a light-emitting layer manufactured by a wet process
has a shorter service life than the one manufactured by vacuum
deposition.
[0007] Organic light-emitting devices have been expected to find
use for thin-film illuminators, thin-film display devices,
illuminators for liquid-crystalline display devices. The
light-emitting device is provided with a plurality of organic
light-emitting elements forming pixels on a substrate. An organic
light-emitting element has a structure with a plurality of organic
layers disposed between upper and lower electrodes. The organic
layers include hole transporting layer, electron transporting layer
and light-emitting layer in which holes are recombined with
electrons. When a voltage is applied between the electrodes, holes
and electrons injected from the electrodes are recombined with each
other in the light-emitting layer to emit light.
[0008] For example, Patent Document 2 discloses an organic
light-emitting element having a stripe-shape lower electrode
transmitting emitted light and upper electrode serving as a common
electrode, wherein one of the electrodes is transparent. Power is
supplied to each side of the lower electrode to diminish uneven
brightness. The lower electrode, when transparent, has a high
resistivity and suffers voltage loss around the center of the
organic light-emitting device by wiring resistance, because of its
high resistivity, to increase power consumption, even when power is
supplied to each side. These troubles also occur with a transparent
upper electrode.
[0009] Ink jetting is one of the processes for manufacturing
organic layers for light-emitting display devices. For example,
Patent Document 3 discloses a process comprising steps for forming
a layer containing a first organic compound by embrocation, for
heating the layer under a vacuum immediately before forming a
layer, e.g., light-emitting layer, containing a second organic
compound, and for forming the layer containing a second organic
compound by vacuum deposition.
PRIOR ART DOCUMENTS
Patent Documents
[0010] Patent Document 1: JP-A-2004-185967 [0011] Patent Document
2: JP-A-2007-173519 [0012] Patent Document 3: W-A-2004-71558
Non-patent Documents
[0012] [0013] Non-patent Document 1: Appl. Phys. Lett., 89, 061111
(2006) [0014] Non-patent Document 2: IDW'06, p. 441 (2006) [0015]
Non-patent Document 3: IDW'07, p. 241 (2007)
SUMMARY OF THE INVENTION
Problems to be Solved by the Invention
[0016] It is an object of the first embodiment of the present
invention is to provide an organic light-emitting display device
having a prolonged service life, wherein its light-emitting layer
can be conveniently manufactured by a wet process
[0017] It is an object of the second embodiment of the present
invention is to provide an organic light-emitting device capable of
reducing power consumption by reducing wiring resistance in the
upper electrode (transparent electrode) which transmits light
emitted from its light-emitting layer.
[0018] The third embodiment of the present invention manufactures
and investigates a prototype element, wherein a light-emitting
layer is formed by embrocation and layers to be stacked thereon are
formed by vacuum deposition.
[0019] The embodiment manufactures two types of elements with a
hole injection layer, hole transporting layer, light-emitting layer
and electron transporting layer disposed between upper and lower
electrodes. One type (Element A) has the hole injection, hole
transporting and light-emitting layers formed by embrocation, and
the electron transporting layer formed by vacuum deposition. The
other type (Element B) has the hole injection and hole transporting
layers formed by embrocation, and the light-emitting and electron
transporting layers formed by vacuum deposition.
[0020] Element A has the light-emitting layer formed by embrocation
whereas Element B has the light-emitting layer formed by vacuum
deposition. Element A has a notably shorter service life than
Element B.
[0021] The embodiment also manufactures another type of element
(Element C) with the light-emitting layer formed by vacuum
deposition, as with Element B, and electron layer formed by vacuum
deposition after the light-emitting layer is exposed, for several
minutes, to an embrocation atmosphere having a dew point of
90.degree. C., which corresponds to a moisture content of about 100
ppb. Element C has a service life notably lower than that of
Element B and on a level with that of Element A.
[0022] The vacuum deposition chamber for vacuum deposition is kept
at 1.times.10.sup.-4 Pa or less. It is estimated that the
atmosphere in the chamber contains moisture at about 10 ppb, on the
assumption that the atmosphere substantially consists of moisture.
The moisture content in the atmosphere for embrocation (about 100
ppb) is much higher than the moisture content (about 10 ppb) in the
atmosphere in the vacuum deposition chamber. It is considered that
the notably deteriorated service life of Element C results from
moisture adsorbed by the light-emitting layer formed by vacuum
deposition.
[0023] Based on the observed life-related characteristics of
Elements A, B and C, the low service life of Element A with the
light-emitting layer formed by embrocation results from moisture
adsorbed by the light-emitting layer. These results indicate that
removal of moisture adsorbed on the organic light-emitting layer,
formed by embrocation, is an effective means for improving service
life of the organic light-emitting element.
[0024] Objects of the present invention are to provide a process
for manufacturing an organic light-emitting element of prolonged
service life, and also to provide an apparatus for manufacturing
the element.
Means for Solving the Problem
[0025] The organic light-emitting display device of the first
embodiment of the present invention is an organic light-emitting
display device comprising:
[0026] a light-emitting layer;
[0027] an upper electrode and a lower electrode sandwiching the
light-emitting layer, wherein one of the electrodes is a
transparent electrode transmitting a light emitted from the
light-emitting layer and the other electrode is a reflective
electrode which reflects a light emitted from the light-emitting
layer; and
[0028] a moisture capturing layer disposed between the upper
electrode and the lower electrode.
[0029] The organic light-emitting device of one embodiment of the
second embodiment of the present invention is an organic
light-emitting device comprising a light-emitting element disposed
on an electroconductive substrate, the light-emitting element
comprising a lower reflective electrode, an organic layer and an
upper transparent electrode, wherein the upper transparent
electrode is connected to the electroconductive substrate via a
contact hole disposed around the lower reflective electrode.
[0030] The organic light-emitting device of another embodiment of
the present invention is an organic light-emitting device
comprising a light-emitting element disposed on an
electroconnductive substrate, the light-emitting element comprising
an organic layer and an upper transparent electrode, wherein the
electroconductive substrate serves as a reflective electrode
capable of reflecting emitted light.
[0031] The third embodiment of the present invention relates to a
method for manufacturing an organic light-emitting element
having:
[0032] a substrate;
[0033] a first electrode and a second electrode formed on the
substrate; and
[0034] a first organic compound including a light-emitting layer
and a second organic compound sandwiched between the first
electrode and the second electrode, comprising the steps of:
[0035] forming the first organic compound;
[0036] heating the first organic compound under a vacuum; and
[0037] forming the second organic compound,
[0038] wherein the step of heating the first organic compound under
a vacuum is carried out between the step of forming the first
organic compound and the step of forming the second organic
compound.
[0039] The present invention also relates to an apparatus for
manufacturing an organic light-emitting element having:
[0040] a substrate;
[0041] a first electrode and a second electrode formed on the
substrate; and
[0042] a first organic compound including a light-emitting layer
and a second organic compound sandwiched between the first
electrode and the second electrode, which apparatus comprises:
[0043] an embrocation chamber for forming the first organic
compound;
[0044] a vacuum heat chamber for heating the first organic compound
under a vacuum;
[0045] a vacuum deposition chamber for forming the second organic
compound;
[0046] a chamber for forming the first electrode by a resistance
heating method or a sputtering method; and
[0047] a transfer chamber for transferring the substrate from the
embrocation chamber to the vacuum heat chamber, from the vacuum
heat chamber to the vacuum deposition chamber, and from the vacuum
deposition chamber to the chamber for forming the first
electrode.
[0048] Another embodiment of the apparatus of the present invention
is an apparatus for manufacturing an organic light-emitting element
having a first organic compound including a light-emitting layer
and a second organic compound sandwiched between a first electrode
and a second electrode, which apparatus comprises:
[0049] an embrocation chamber for forming the first organic
compound;
[0050] a vacuum deposition chamber for forming the second organic
compound;
[0051] a chamber for forming the first electrode by a resistance
heating method or a sputtering method; and
[0052] a transfer chamber for transferring a substrate from the
embrocation chamber to the vacuum deposition chamber, and from the
vacuum deposition chamber to the chamber for forming the first
electrode,
[0053] wherein a high-frequency dielectric device or a microwave
generator is disposed in the transfer chamber.
[0054] Still another embodiment of the apparatus of the present
invention is an apparatus for manufacturing an organic
light-emitting element having:
[0055] a substrate;
[0056] a first electrode and a second electrode formed on the
substrate; and
[0057] a first organic compound including a light-emitting layer
and a second organic compound sandwiched between the first
electrode and the second electrode, which apparatus comprises;
[0058] an embrocation chamber for forming the first organic
compound;
[0059] a vacuum deposition chamber for forming the second organic
compound;
[0060] a chamber for forming the first electrode by a resistance
heating method or a sputtering method; and
[0061] a transfer chamber for transferring the substrate from the
embrocation chamber to the vacuum deposition chamber, and from the
vacuum deposition chamber to the chamber for forming the first
electrode,
[0062] wherein a high-frequency dielectric device or a microwave
generator is disposed in the vacuum deposition chamber.
Advantages of the Invention
[0063] The first embodiment of the present invention is an organic
light-emitting display device which can be conveniently
manufactured to have a structure for suppressing moisture-caused
deterioration of light-emitting layer.
[0064] The second embodiment of the present invention is an organic
light-emitting device capable of reducing power consumption by
reducing wiring resistance in an upper transparent electrode.
[0065] The third embodiment of the present invention provides a
method for manufacturing an organic light-emitting element having a
prolonged service life and apparatus for manufacturing the
element.
BRIEF DESCRIPTION OF THE DRAWINGS
[0066] FIG. 1 is a cross-sectional view illustrating a red-color
pixel in an organic light-emitting display device of the first
embodiment of the present invention, manufactured in one
Example.
[0067] FIG. 2 is a cross-sectional view illustrating an organic EL
layer in the device illustrated in FIG. 1.
[0068] FIG. 3 is a cross-sectional view illustrating a red-color
pixel in an organic light-emitting display device of the first
embodiment of the present invention, manufactured in another
Example.
[0069] FIG. 4 is a cross-sectional view illustrating an organic EL
layer in the device illustrated in FIG. 3.
[0070] FIG. 5 is a cross-sectional view illustrating a red-color
pixel in an organic light-emitting display device of the first
embodiment of the present invention, manufactured in still another
Example.
[0071] FIG. 6 is a cross-sectional view illustrating an organic EL
layer in the device illustrated in FIG. 5.
[0072] FIG. 7 is a cross-sectional view illustrating a red-color
pixel in an organic light-emitting display device of the first
embodiment of the present invention, manufactured in still another
Example.
[0073] FIG. 8 is a cross-sectional view illustrating an organic EL
layer in the device illustrated in FIG. 7.
[0074] FIG. 9 is a cross-sectional view illustrating a red-color
pixel in an organic light-emitting display device of the first
embodiment of the present invention, manufactured in still another
Example.
[0075] FIG. 10 is a cross-sectional view illustrating an organic EL
layer in the device illustrated in FIG. 9.
[0076] FIG. 11 is a cross-sectional view illustrating a red-color
pixel in an organic light-emitting display device of the first
embodiment of the present invention, manufactured in still another
Example.
[0077] FIG. 12 is a cross-sectional view illustrating a red-color
pixel in an organic light-emitting display device of the first
embodiment of the present invention, manufactured in still another
Example.
[0078] FIG. 13 is a cross-sectional view illustrating an organic EL
layer in the device illustrated in FIG. 12.
[0079] FIG. 1A is a cross-sectional view illustrating an organic
light-emitting device of the second embodiment of the present
invention, manufactured in Example 1A.
[0080] FIG. 2A is a plan view illustrating the device illustrated
in FIG. 1A.
[0081] FIG. 3A is a cross-sectional view illustrating an organic
light-emitting device, manufactured in Example 2A.
[0082] FIG. 4A is a plan view illustrating the device illustrated
in FIG. 3A.
[0083] FIG. 5A is a cross-sectional view illustrating an organic
light-emitting device, manufactured in Example 3A.
[0084] FIG. 6A is a plan view illustrating the device illustrated
in FIG. 5A.
[0085] FIG. 7A is a cross-sectional view illustrating an organic
light-emitting device, manufactured in Example 4A.
[0086] FIG. 8A is a plan view illustrating the device illustrated
in FIG. 7A.
[0087] FIG. 9A is a plan view illustrating the device illustrated
in FIG. 7A.
[0088] FIG. 10A is a cross-sectional view illustrating an organic
light-emitting device, manufactured in Example 5A.
[0089] FIG. 11A is a plan view illustrating the device illustrated
in FIG. 10A.
[0090] FIG. 12A is a plan view illustrating the device illustrated
in FIG. 10A.
[0091] FIG. 13A is a cross-sectional view illustrating an organic
light-emitting device, manufactured in Example 6A.
[0092] FIG. 14A is a plan view illustrating the device illustrated
in FIG. 13A.
[0093] FIG. 15A is a plan view illustrating the device illustrated
in FIG. 13A.
[0094] FIG. 16A is a cross-sectional view illustrating an organic
light-emitting device, manufactured in Example 7A.
[0095] FIG. 17A is a plan view illustrating the device illustrated
in FIG. 16A.
[0096] FIG. 1BA is a plan view illustrating the device illustrated
in FIG. 16A.
[0097] FIGS. 1B (A), (B), (C), (D) and (E) illustrate process steps
of the third embodiment of the present invention for manufacturing
an organic light-emitting element.
[0098] FIG. 2B is a cross-sectional view illustrating the organic
light-emitting element manufactured by the third embodiment of the
present invention, emitting light from a second electrode.
[0099] FIG. 3B is a cross-sectional view illustrating the organic
light-emitting element manufactured by the third embodiment of the
present invention, emitting light from a first electrode.
[0100] FIG. 4B is a cross-sectional view illustrating the organic
light-emitting element manufactured by the third embodiment of the
present invention, emitting light from a first electrode.
[0101] FIG. 5B is a process chart for manufacturing an organic
light light-emitting element by the third embodiment of the present
invention.
[0102] FIG. 6B outlines the apparatus structure of the third
embodiment of the present invention for manufacturing an organic
light-emitting element.
[0103] FIG. 7B outlines the vacuum chamber structure in the
apparatus of the third embodiment of the present invention,
provided with a high-frequency dielectric device.
[0104] FIG. 8B outlines the transfer chamber structure in the
apparatus of the third embodiment of the present invention,
provided with a high-frequency dielectric device.
[0105] FIG. 9B outlines the apparatus structure of the third
embodiment of the present invention for manufacturing an organic
light-emitting element, provided with a high-frequency dielectric
device.
[0106] FIG. 10B outlines the vacuum chamber structure in the
apparatus of the third embodiment of the present invention,
provided with a high-frequency dielectric device.
DESCRIPTION OF REFERENCE NUMERALS
[0107] 1, 21, 41, 61, 81, 101, 121: Glass substrate [0108] 2, 22,
42, 62, 82, 102, 122: First interlayer insulating film [0109] 3,
23, 43, 63, 83, 103, 123: Second interlayer insulating film [0110]
4, 24, 44, 64, 84, 104, 124: Power line [0111] 5, 25, 45, 65, 85,
105, 125: Image signal line [0112] 6, 26, 46, 66, 86, 106, 126:
Third interlayer insulating film [0113] 7, 27, 47, 67, 87, 107:
Transparent electrode (lower electrode) [0114] 8, 28, 48, 68, 88,
128: Bank [0115] 9, 29, 49, 69, 91, 129: Organic EL layer [0116]
10, 30, 51, 71, 111, 130: Blocking layer [0117] 11, 50, 70, 90,
112, 132: Moisture capturing layer [0118] 12, 32, 52, 72, 92, 113,
132: Electron transporting layer [0119] 13, 33, 53, 73, 93, 114:
Upper electrode [0120] 14, 34, 54, 74, 89, 108, 134: Hole injection
layer [0121] 15, 35, 55, 75, 94, 109, 135: Hole transporting layer
[0122] 16, 36, 56, 76, 95, 110, 136: Light-emitting layer [0123]
127: Reflective electrode (lower electrode) [0124] 133: Transparent
electrode (upper electrode) [0125] 1A: Insulating film [0126] 2A:
Metallic substrate [0127] 3A: First interlayer insulating film
[0128] 4A: Lower reflective electrode [0129] 5A: Connecting
electrode [0130] 6A: Second interlayer insulating film [0131] 7A:
Hole transporting layer [0132] 8A: White-color-emitting layer
[0133] 9A: Electron transporting layer [0134] 10A: Electron
injection layer [0135] 11A: Upper transparent electrode [0136] 12A,
20A, 40A, 50A, 70A: Contact hole [0137] 13A: OLED substrate [0138]
14A: Sealing substrate [0139] 21A, 32A, 41A, 51A, 71A: Auxiliary
interconnector [0140] 31A: Composite substrate [0141] 42A: Third
interlayer insulating film [0142] 101B, 702, 802, 1002: Substrate
[0143] 102B: TFT-containing layer [0144] 103B, 205, 305, 405:
Second electrode [0145] 104B: Diaphragm (Barrier rib) [0146] 105B:
First organic compound [0147] 106B: Second organic compound [0148]
107B, 201, 301, 401: First electrode [0149] 108B: Heating apparatus
(Heat generator) [0150] 202, 302, 404: Electron transporting layer
[0151] 203, 303, 403: Light-emitting layer [0152] 204, 304, 402:
Hole transporting layer [0153] 406: Hole injection layer [0154]
501, 601, 901: Embrocation chamber (Application chamber) [0155]
502, 602, 701, 701A, 701B: Vacuum chamber for heating (Vacuum heat
chamber) [0156] 503, 603, 902, 1001, 1001A, 1001B: Vacuum
deposition chamber [0157] 504, 604, 903: Chamber for forming first
electrode [0158] 505, 605, 904: Sealing chamber [0159] 606, 801,
801A, 801B: Transfer chamber [0160] 703, 803, 1003: High-frequency
dielectric device
EMBODIMENTS FOR CARRYING OUT THE INVENTION
[0161] Examples (Examples 1 to 7) for manufacturing the organic
light-emitting display devices of the first embodiment of the
present invention are described below by referring to FIGS. 1 to
13.
[0162] Examples (Examples 1A to 7A) for manufacturing the organic
light-emitting devices of the second embodiment of the present
invention are described below by referring to FIGS. 1A to 18A.
[0163] Examples (Examples 1B to 7B) describe the third embodiment
of the present invention below in detail by referring to FIGS. 1B
to 10B. It should be understood that the present invention is not
limited by these examples.
EXAMPLES
Example 1
[0164] FIG. 1 presents a cross-sectional view illustrating a
red-color pixel structure in a bottom emission type organic
light-emitting display device, in which light emitted from a
light-emitting layer is emitted from a lower electrode. Referring
to FIG. 1, a glass substrate 1 supports a first interlayer
insulating film 2, second interlayer insulating film 3, power line
4, image signal line 5, third interlayer insulating film 6,
transparent electrode 7 (lower electrode), bank 8, organic EL layer
9, blocking layer 10, moisture capturing layer 11, electron
transporting layer 12 and upper electrode 13 (reflective
electrode), in this order from the substrate 1. FIG. 2 presents a
cross-sectional view illustrating the organic EL layer 9 disposed
around the center of the pixel. It is composed of a hole injection
layer 14, hole transporting layer 15 and light-emitting layer 16,
in this order from the bottom.
[0165] The moisture capturing layer 11 is disposed between the
transparent electrode 7 (lower electrode) and reflective electrode
13 (upper electrode).
[0166] The lower electrode 7 is a transparent electrode capable of
transmitting light emitted from the light-emitting layer 16. The
lower electrode 7 is made of ITO, and may be pattered by
photolithography. Any material may be used for the lower electrode
7, so long as it has transparency and high work function, e.g., IZO
and other electroconductive oxides in addition to ITO, and metals
of high work function (e.g., thin Ag).
[0167] The bank 8 works to separate the adjacent pixels from each
other. The bank 8 is made of an acryl-base resist, and the pattern
is formed by photolithography. The bank 8 is surface-treated with
CF.sub.4 plasma to be water-repellent, after the bank 8 becomes
insolubilized under heating. The bank 8 may be made of other
high-molecular-weight materials, e.g., polyimide, phenol, novolac
and epoxy resins.
[0168] The hole injection layer 14 injects holes transferred from
the lower electrode 7. The hole injection layer 14 is made of
poly(3,4-ethylene dioxythiophene) (PEDOT): polystyrene sulfonate
(PSS). Other materials useful for the hole injection layer 14
include polypyrrole-base and tirphenylamine-base polymers in
addition to PEDOT:PSS. Moreover, they may be combined with a
low-molecular-weight compound, and phthalocyanine-base and
starburst-amine-base compounds may be also used.
[0169] The hole transporting layer 15 is a layer for transporting
(transferring) a hole. The hole transporting layer 15 is made of an
arylamine-base polymer. Other polymers useful for the hole
transporting layer 15 include polyfluorene-base,
polyparaphenylene-base, polyarylene-base and polycarbazole-base
ones.
[0170] The light-emitting layer 16 provides the space in which
injected holes and electrons are recombined with each other to emit
light of wavelength determined by the layer constituent. The
light-emitting layer 16 contains a host material doped with a
light-emitting dopant. Example 1 uses 4,4'-di(N-carbazolyl)biphenyl
(CBP), represented by the following Formula (h1) as the host
material and an Ir complex, represented by the following Formula
[d1], as the dopant material, where host/dopant ratio is set at
10/1 by mass. The light-emitting layer 16 is formed by a wet
process, wherein a coating solution manufactured by dissolving the
host material and dopant in a solvent is spread to form the layer.
The applicable wet processes include ink jetting, printing and
spraying, and ink jetting is used in Example 1 with the solution
containing solids at 0.5% by mass. The solution for ink jetting
preferably has a viscosity of from 1 to 20 mPas at room
temperature. The solid concentration in the solution is not
limited, so long as the solution gives a desired layer thickness.
Example 1 uses a mixed polar solvent of aromatic-base, alcohol-base
solvents or the like. These solvents may be used individually.
##STR00001##
[0171] These materials for the host material and dopant are not
limited to the above. For example, the useful host materials
include carbazole derivative, e.g.,
4,4',4''-tri(N-carbazolyl)triphenylamine (TCTA) and
N,N'-dicarbazolyl-3,5-benzene (mCP); quinolinol complex, e.g.,
aluminum(III)bis(2-methyl-8-quinolinate)-4-(phenylphenolate)
(Balq); and iridium complex. They may be used in combination. The
host material may be incorporated with a high-molecular-weight
material, e.g., polycarbonate, working as a binder. Moreover, they
may be incorporated with a hole transporting material, e.g., a
triphenylamine derivative, or electron transporting material, e.g.,
an oxadiazole derivative or triazole derivative. The other
materials useful for the light-emitting dopant include
phosphorescent materials, e.g., other Ir complex, and Pt and Os
complexes. Fluorescent materials, e.g., distyrylamine derivative,
coumarin derivative and quinacridone derivative, are also
useful.
[0172] The blocking layer 10 blocks movements of the exciters
formed in the light-emitting layer 16 and holes injected into the
light-emitting layer 16 toward the electron transporting layer 12.
Example 1 uses
aluminum(III)bis(2-methyl-8-quinolinate)-4-(phenylphenolate) (Balq)
for the blocking layer 10. The material useful for the blocking
layer 10 is not limited to Balq. Examples of the other useful
materials include another quinolinol derivative, oxazole
derivativs, triazole complex and polynuclear hydrocarbon.
[0173] The moisture capturing layer 11, which is one of the major
features of the present invention, captures moisture present in the
thin film in the element. Example 1 uses barium oxide for the
moisture capturing layer 11. The material useful for the moisture
capturing layer 11 is not limited to barium oxide. Examples of the
other useful materials include oxides, e.g., lithium oxide, calcium
oxide, strontium oxide, aluminum oxide and diphosphate pentaoxide;
metals, e.g., Li, Ba, Ca and Cs; metallic carbonates, e.g., calcium
carbide; and Schiff base, e.g., that represented by the following
Formula [w1]. They may be used either individually or in
combination.
##STR00002##
R: --H, --CH.sub.3 or the like
[0174] The electron transporting layer 12 transports (transfers)
electrons. Example 1 uses tris(8-quinolinolate) aluminum
(Alq.sub.3) for the layer 12. The material useful for the layer 12
is not limited to Alq.sub.3. Examples of the other useful materials
include another quinolinol derivative, and oxadiazole derivative,
triaszole derivative, fllerene derivative, phenanthroline
derivative and quinoline derivative.
[0175] The upper electrode 13 is a reflective electrode which is
capable of reflecting light emitted from the light-emitting layer
16. Example 1 uses a laminate of LiF and Al for the upper electrode
13. The materials useful for the upper electrode 13 are not limited
to them. Examples of the other useful materials include Cs, Ba and
Ca compounds, e.g. other than LiF, and an electron transporting
material co-deposited with an alkaline metal (e.g., Li or Cs),
alkaline-earth metal or an electron donating organic material.
[0176] FIG. 3 presents a cross-sectional view illustrating a
red-color pixel manufactured in Comparative Example 1, and FIG. 4
presents a cross-sectional view illustrating the organic EL layer
29 in the pixel illustrated in FIG. 3. The pixel illustrated in
FIG. 3 (Comparative Example 1) differs from that illustrated in
FIG. 1 in that it has no moisture capturing layer 1 (cf. FIG.
1).
[0177] The pixel manufactured in Example 1 has a 1.2 times higher
brightness half period than that manufactured in Comparative
Example 1. The organic light-emitting display device manufactured
in Example 1 has a reduced amount of moisture present in the
light-emitting layer 16 to suppress moisture-caused deterioration,
and can prolong service life of the device.
[0178] The device manufactured in Example 1 has the blocking layer
10 and electron transporting layer 12 of the common material in
each pixel. The present invention is not limited to such a
structure. However, the blocking layer 10 and the electron
transporting layer 12 may be of different materials pixel by
pixel.
Example 2
[0179] FIG. 5 presents a cross-sectional view illustrating a
red-color pixel manufactured in Example 2, and FIG. 6 presents a
cross-sectional view illustrating an organic EL layer 49 in the
pixel illustrated in FIG. 5. The pixel illustrated in FIG. 5
differs from that illustrated in FIG. 1 in that it has a moisture
capturing layer 50 disposed between a light-emitting layer 56 and
blocking layer 51 and that the light-emitting layer 56 has a
so-called graded structure with a dopant dispersed at a lower
concentration in the vicinity of the blocking layer 51 than in the
vicinity of a hole transporting layer 55.
[0180] The pixel manufactured in Example 2 has a 1.2 times higher
brightness half period than that manufactured in Comparative
Example 1.
Example 3
[0181] FIG. 7 presents a cross-sectional view illustrating a
red-color pixel manufactured in Example 3, and FIG. 8 presents a
cross-sectional view illustrating an organic EL layer 69 in the
pixel illustrated in FIG. 7. The pixel illustrated in FIG. 7
differs from that illustrated in FIG. 5 in that its light-emitting
layer 76 contains Balq as a host material in place of CBP. CBP has
a hole mobility and electron mobility on a level with each other,
and can transfer both of these carriers. On the other hand, Balq is
a so-called electron transporting material having an electron
mobility higher than hole mobility. As a result, recombination of
the electrons and holes occurs in the vicinity of a hole
transporting layer 75 in the light-emitting layer 76.
[0182] The pixel manufactured in Example 3 has a 1.5 times higher
brightness half period than that manufactured in Comparative
Example 1.
Example 4
[0183] The pixel manufactured in Example 4 is the same as that
manufactured in Example 1, illustrated in FIG. 1, except that its
light-emitting layer 16 contains polycarbonate [Formula 3]. The
pixel manufactured in Example 4 has a 1.3 times higher brightness
half period than that manufactured in Comparative Example 1.
##STR00003##
Example 5
[0184] FIG. 9 presents a cross-sectional view illustrating a
red-color pixel manufactured in Example 5, and FIG. 10 presents a
cross-sectional view illustrating an organic EL layer 91 in the
pixel illustrated in FIG. 9. The pixel manufactured in Example 5 is
the same as that manufactured in Example 1, except that a moisture
capturing layer 90 is disposed between a hole injection layer 89
and hole transporting layer 94. The pixel manufactured in Example 5
has a 1.2 times higher brightness half period than that
manufactured in Comparative Example 1.
Example 6
[0185] FIG. 11 presents a cross-sectional view illustrating a
red-color pixel manufactured in Example 6. It is the same as that
manufactured in Example 1, illustrated in FIG. 1, except that a
liquid-repellent thin film of a fluorine compound, not shown in
FIG. 11, is disposed in place of the bank 8 illustrated in FIG. 1
between the adjacent pixels. The thin film can be controlled for
solubility/insolubility, when irradiated with light, to form the
liquid-repellent segment between the adjacent pixels. This allows a
light-emitting layer 110 to be formed selectively in the pixel.
[0186] The pixel manufactured in Comparative Example 2 is the same
as that manufactured in Example 6, except that it has no moisture
capturing layer 11 (illustrated in FIG. 1) in Comparative Example
2. The pixel manufactured in Example 6 has a 1.2 times higher
red-color brightness half period than that manufactured in
Comparative Example 2.
Example 7
[0187] FIG. 12 presents a cross-sectional view illustrating a
red-color pixel manufactured in Example 7, and FIG. 13 presents a
cross-sectional view illustrating an organic EL layer 129 in the
pixel illustrated in FIG. 12. The pixel manufactured in Example 7
is the same as that manufactured in Example 1, except that it uses
a lower electrode (reflective electrode) having a laminated
structure of Al/ITO, in place of the lower electrode (transparent
electrode) in the pixel illustrated in FIG. 1. The laminate
materials are not limited to the above. For example, Al may be
replaced by Ag, or the like and ITO may be replaced by IZO or ZnO,
which is also transparent. The laminated structure of metal and
transparent, electroconductive film may be replaced by Cr or
MoW.
[0188] The red-color pixel manufactured in Comparative Example 3 is
the same as that manufactured in Example 7, except that it has no
moisture capturing layer 131 illustrated in FIG. 12. The pixel
manufactured in Example 7 has a 1.2 times higher red-color
brightness half period than that manufactured in Comparative
Example 3.
[0189] The organic light-emitting display device with the pixel
manufactured in Example 7 has a so-called top cathode, top emission
type structure. However, the present invention is not limited to
this structure, and also applicable to a so-called top anode type
structure.
[0190] Examples described above only describe a red-color emitting
pixel. However, the present invention is also applicable to pixels
emitting other colors by adequately selecting materials for the
light-emitting dopant, hole transporting layer and electron
transporting layer. For example, the present invention can emit
green and blue colors by using the light-emitting dopants
represented by respective Formulae [d2] and [d3] as follows. The
materials are not limited to the above. Use of a material of
point-asymmetric structure can further improve device
performance.
##STR00004##
Example 1A
[0191] Examples (Examples 1A to 7A) for manufacturing the organic
light-emitting devices of the second embodiment of the present
invention are described. First, the organic light-emitting device
manufactured in Example 1A is described. FIG. 1A presents a
cross-sectional view illustrating an organic light-emitting device
manufactured in Example 1A, and FIG. 2A presents a plan view
illustrating the device illustrated in FIG. 1A.
[0192] The organic light-emitting device has a metallic substrate
2A which supports an organic light-emitting element composed of a
lower reflective electrode 4A serving as an anode, hole
transporting layer 7A, white-color-emitting layer 8A, electron
transporting layer 9A, electron injection layer 10A and upper
transparent electrode 11A serving as a cathode, disposed in this
order from the substrate 2A. It may have a hole injection layer, as
required, disposed between the lower reflective electrode 4A and
hole transporting layer 7A. Moreover, it may have a structure with
the hole transporting layer 7A and electron transporting layer 9A
serving as the white-color-emitting layer 8A.
[0193] The upper transparent electrode 11A transmits emitted light,
and the lower reflective electrode 4A reflects emitted light.
[0194] The device also has a sealing substrate 14A disposed on the
upper transparent electrode 11A in the light-emitting element. The
sealing substrate 14A works to block inflow of H.sub.2O and O.sub.2
present in the atmosphere into the upper transparent electrode 11A
and organic layers disposed below (hole transporting layer 7A,
electron transporting layer 9A and white-color-emitting layer 8A).
The materials useful for the sealing substrate 14A include
inorganic materials, e.g., SiO.sub.2, SiNx and Al.sub.2O.sub.3; and
organic compounds, e.g., polychloropyrene,
polyethyleneterephthalate, polyoxymethylene, polyvinyl chloride,
polyvinylidene fluoride, cyanoethylpullulan,
polymethylmethacrylate, polysulfone, polycarbonate and
polyimide.
[0195] The metallic substrate 2A is coated with a 2 .mu.m thick
acrylic insulating layer as a first interlayer insulating film 3A
on the light-emitting element side, and with an insulating film 1A
on the other side. Example 1A uses an acrylic insulating layer for
the first interlayer insulating film 3A. Other materials useful for
the film 3A include organic insulating materials, e.g.,
polychloropyrene, polyethyleneterephthalate, polyoxymethylene,
polyvinyl chloride, polyvinylidene fluoride, cyanoethylpullulan,
polymethylmethacrylate, polysulfone, polycarbonate and polyimide;
and inorganic materials, e.g., SiO.sub.2, SiNx and Al.sub.2O.sub.3.
They may be used either individually or in combination. For
example, the film 3A may have a laminated structure with an
inorganic insulating film disposed on an organic insulating
film.
[0196] The metallic substrate 2A is an electroconductive substrate
and also works as an auxiliary interconnector for applying a
voltage to the light-emitting element (composed of the lower
reflective electrode 4A, hole transporting layer 7A,
white-color-emitting layer 8A, electron transporting layer 9A,
electron injection layer 10A and upper transparent electrode 11A)
or as the reflective electrode capable of reflecting emitted light.
Any material may be used for the metallic substrate 2A, so long as
it is electroconductive. The useful materials include metals, e.g.,
aluminum, indium, molybdenum, nickel, copper, iron and their
alloys.
[0197] The insulating film 1A insulates the metallic substrate 2A
to which to a voltage is applied. Organic insulating materials are
useful for the insulating film 1A. These materials include acryl,
polychloropyrene, polyethyleneterephthalate, polyoxymethylene,
polyvinyl chloride, polyvinylidene fluoride, cyanoethylpullulan,
polymethylmethacrylate, polysulfone, polycarbonate and
polyimide.
[0198] Next, the first interlayer insulating film 3A is provided
with a plurality of contact holes 12A. The film 3A is coated with a
150 nm thick Al film to form the lower reflective electrode 4A and
connecting electrode 5A. Example 1A uses an aluminum film for the
lower reflective electrode 4A. The film material is not limited to
aluminum, and the useful materials include metals, e.g., indium,
molybdenum, nickel and their alloys; and inorganic materials, e.g.,
polysilicon and amorphous silicon. Also preferable are laminated
structures with an electroconductive, transparent electrode of tin
oxide, indium oxide, indium-tin-oxide (ITO) or the like disposed on
the above metals or their alloys.
[0199] Example 1A forms the lower reflective electrode 4A and
connection electrode 5A using the same aluminum film. However, they
may be made of different materials. For example, the lower
reflective electrode 4A may be made of a laminated film with an Al
film and In--Sn--O film (ITO film), and the connection electrode 5A
may be made of an ITO film. A different metallic film may be made
for each of these electrodes.
[0200] Next, a second interlayer insulating film 6A is formed to
cover the lower reflective electrode 4A and connection electrode 5A
edges. Example 1A also uses an acrylic insulating film for the film
6A. However, another compound may be used for the film. The useful
compounds for the film 6A include organic compounds, e.g.,
polychloropyrene, polyethyleneterephthalate, polyoxymethylene,
polyvinyl chloride, polyvinylidene fluoride, cyanoethylpullulan,
polymethylmethacrylate, polysulfone, polycarbonate and polyimide;
and inorganic materials, e.g., SiO.sub.2, SiNx and Al.sub.2O.sub.3.
Moreover, the film 6A may have a laminated structure with an
inorganic insulating film disposed on an organic insulating
film.
[0201] Next, a 50 nm thick
4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (.alpha.-NPD) vacuum
deposition film is formed on the lower reflective electrode 4A by a
vacuum deposition method. The vacuum deposition film is disposed
around the lower reflective electrode 4A but not on the connection
electrode 5A to work as the hole transporting layer 7A.
[0202] Example 1A uses .alpha.-NPD vacuum deposition film for the
hole transporting layer 7A. However, other compounds may be used.
The hole transporting layer 7A transports holes and injects them
into the white-color-emitting layer 8A. Therefore, it is preferably
made of a hole transporting material of high hole mobility. It is
also preferable that the layer 7A is made of a compound which is
chemically stable, low in ionization potential, low in affinity for
electrons and high in glass transition temperature. The preferable
compounds for the layer 7A include:
N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diam-
ine (TPD), 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl
(.alpha.-NPD),
1,3,5-tris[N-(4-diphenylaminophenyl)phenylamino]benzene
(p-DPA-TDAB), 4,4'-4''-tris(N-carbazol)triphenylamine (TCTA),
1,3,5-tris[N,N-bis(2-methylphenyl)-amino]-benzene (o-MTDAB),
1,3,5-tris[N,N-bis(3-methylphenyl)-amino]-benzene (m-MTDAB),
1,3,5-tris[N,N-bis(4-methylphenyl)-amino]-benzene (p-MTDAB),
4,4',4''-tris[1-naphthyl(phenyl)amino]triphenylamine (1-TNATA),
4,4',4''-tris[2-naphthyl(phenyl)amino]triphenylamine (2-TNATA),
4,4',4''-tris[biphen-4-yl-(3-methylphenyl)amino]triphenylamine
(p-PMTDATA),
4,4',4''-tris[9,9-dimethylfluoren-2-yl(phenyl)amino]triphenylamine
(TFATA), 4,4',4''-tris(N-carbazoyl)triphenylamine (TCTA),
1,3,5-tris-[N-(4-diphenylaminophenyl)phenylamino]benzene
(p-DPA-TDAB),
1,3,5-tris-{4-[methylphenyl(phenyl)amino]phenyl}benzene (MTDAPB),
N,N'-di(biphen-4-yl)-N,N'-diphenyl[1,1'-biphenyl]-4,4'-diamine
(p-BPD),
N,N'-bis(9,9-dimethylfluoren-2-yl)-N,N'-diphenylfluorene-2,7-diamine
(PFFA),
N,N,N',N'-tetrakis(9,9-dimethylfluoren-2-yl)-[1,1-biphenyl]-4,4'--
diamikne (FFD), (NDA)PP, and
4-4'-bis[N,N'-(3-tolyl)amino]-3-3'-dimethylbiphenyl (HMTPD). They
may be used either individually or in combination.
[0203] A hole injection layer may be disposed, as required, between
the lower reflective electrode 4A and the hole transporting layer
7A. The hole injection layer preferably has an adequate ionization
potential for lowering an injection barrier between the lower
reflective electrode 4A and the hole transporting layer 7A. It also
preferably works to smoothen rough surface of an under layer. The
useful compounds for the hole injection layer include, but not
limited to, copper phthalocyanine, starburst amine, polyaniline,
polythiophene, vanadium oxide, molybdenum oxide, ruthenium oxide
and aluminum oxide.
[0204] The hole transporting material may be incorporated with an
oxidant, to lower a barrier between it and the lower reflective
electrode 4A or improve its electroconductivity. The useful
oxidants include, but not limited to, Lewis acid compounds, e.g.,
ferric chloride, ammonium chloride, gallium chloride, indium
chloride, antimony pentachloride; and electron acceptable
compounds, e.g., trinitrofluorene; and vanadium oxide, molybdenum
oxide ruthenium oxide and aluminum oxide cited as the hole
injection compounds. They may be used either individually or in
combination.
[0205] Next, the hole transporting layer 7A is coated with a 20 nm
thick composite film (co-deposited film) with 4,4'-di(N-carbazole)
biphenyl (CBP) and
bis[2-(2'-benzo[4,5-a]thienyl)pyridinate-N,C3']iridium(acetylac-
etonate) (Brp.sub.2Ir(acac)), co-deposited under a vacuum. The CBP
and Brp.sub.2Ir(acac) deposition rates are set at 0.20 nm/second
and 0.02 nm/second, respectively. Brp.sub.2Ir(acac) works as a
dopant that determines emitted light color. The composite film of
CBP and Brp.sub.2 Ir (acac) is pattered using a precision mask with
a pattern of openings, each being similar in size to the lower
reflective electrode 4A.
[0206] Next, the composite film of CBP and Brp.sub.2Ir(acac) is
coated with a 40 nm thick composite film (co-deposited film) with
CBP and iridium complex (Ir(ppy).sub.3) co-deposited under a
vacuum. The CBP and Ir(ppy).sub.3 deposition rates are set at 0.20
nm/second and 0.02 nm/second, respectively. Ir(ppy).sub.3 works as
a dopant that determines emitted light color. The CBP/Ir(ppy).sub.3
composite film is pattered using a precision mask with a pattern of
openings, each being similar in size to the lower reflective
electrode 4A.
[0207] The above two-layered co-deposited structure (film) works as
the white-color-emitting layer 8A. Example 1A uses a laminated
structure of red-color-emitting and blue-color-emitting films for
the white-color-emitting layer 8A. However, the structure is not
limited to the above. More specifically, the structures of the
white-color-emitting layer 8A may be two-layered laminate with
orange-color-emitting and blue-color-emitting layers, and
yellow-color-emitting and blue-color-emitting layers; three-layered
laminate with red-color-emitting, green-color-emitting and
blue-color-emitting layers; and single layer incorporated with a
plurality species of light-emitting dopants dispersed in the host
material.
[0208] The white-color-emitting layer 8A provides the space in
which injected holes and electrons are recombined with each other
to emit light of wavelength determined by the layer constituent,
wherein light is emitted from the host material itself forming the
white-color-emitting layer 8A or from a small amount of the
light-emitting dopant dispersed in the host material. The useful
host materials include, but not limited to, a distyrylarylene
derivative (DPVBi), silole derivative with a benzene ring in the
skeleton (2PSP), oxadiazole derivative with a triphenylamine
structure at both ends (EM2), perinone derivative with a
phenanthrene group (P1), oligothiophene derivative with a
triphenylamine structure at both ends (BMA-3T), perylene derivative
(t-Bu-PTC), tris(8-quinolinol) aluminum, polyparaphenylenevinylene
derivative, polythiophene derivative, polyparaphenylene derivative,
polysilane derivative and polyacetylene derivative. They may be
used either individually or in combination.
[0209] The useful dopant materials include, but not limited to,
quinacridone, coumarin 6, Nile red, rubrene,
4-(dicyanomethylene)-2-methyl-6-(para-dimethylaminostyryl)-4H-pyrane
(DCM), dicarbazole derivative, porphyrin/platinum complex (PtOEP),
iridium complex (Ir(ppy).sub.3). They may be used either
individually or in combination.
[0210] Next, the white-light-emitting layer 8A is coated with a 15
nm thick tris(8-quinolinolate) aluminum (Alq.sub.3) film by vacuum
deposition. The deposited film works as the electron transporting
layer 9A.
[0211] The electron transporting layer 9A transports (transfers)
electrons and injects them into the white-color-emitting layer 8A.
Therefore, it is preferably made of an electron transporting
material of high electron mobility. The materials useful for the
layer 9A are not limited, but the preferable ones include
tris(8-quinolinol) aluminum, oxadiazole derivative, silole
derivative, zinc/benzothiazole complex and basocuproin (BCP). They
may be used either individually or in combination.
[0212] The electron transporting (transfer) material for the
electron transporting layer 9A is preferably incorporated with a
reductant, to lower a barrier between it and the upper transparent
electrode 11A or improve its electroconductivity. The useful
reductants include, but not limited to, alkaline metals,
alkaline-earth metals, alkaline metal oxides, alkaline-earth metal
oxides, rare-earth metal oxides, alkaline metal halides,
alkaline-earth metal halides, rare earth metal halides and alkaline
metal/aromatic compound complexes, of which especially preferable
alkaline metals are Cs, Li, Na and K. They may be used either
individually or in combination.
[0213] Next, the electron transporting layer 9A is coated with a
Mg/Ag composite film working as the electron injection layer 10A by
co-deposition carried out under a vacuum, wherein the Mg and Ag
deposition rates are set at 0.14.+-.0.05 nm/second and
0.01.+-.0.005 nm/second, respectively.
[0214] The electron injection layer 10A works to improve efficiency
of injecting electrons transferred from the upper transparent
electrode 11A into the electron transporting layer 9A. The
preferable materials for the layer 10A include, but not limited to,
lithium fluoride, magnesium fluoride, calcium fluoride, strontium
fluoride, barium fluoride, magnesium fluoride and aluminum
fluoride. They may be used either individually or in
combination.
[0215] Next, a 50 nm thick amorphous In--Zn--O (IZO) film working
as the upper transparent electrode 11A is formed by sputtering with
a target of In and Zn (In/(In+Zn) ratio: 0.83) under the conditions
of atmosphere: mixed Ar/O.sub.2 gas, degree of vacuum: 0.2 Pa and
sputtering output: 2 W/cm.sup.2. The laminate of the Mg/Ag film and
IZO film has a light transmittance of 65%.
[0216] The upper transparent electrode 11A is electrically
connected to the metallic substrate 2A via the connecting electrode
5A contacting with the contact holes 12A. Example 1A uses the
connecting electrode 5A to prevent disconnection between the upper
transparent electrode 11A and metallic substrate 2A at the contact
holes 12A. However, the upper transparent electrode 11A may be
connected to the metallic substrate 2A.
[0217] Thus, an OLED substrate 13A is formed, the substrate being
provided with the metallic substrate 2A and a plurality of the
stripe-shape organic light emitting elements (each comprising the
lower reflective electrode 4A, hole transporting layer 7A,
white-color-emitting layer 8A, electron transporting layer 9A,
electron injection layer 10A and upper transparent electrode
11A).
[0218] Next, the OLED substrate 13A is transferred to a sealing
chamber kept at a high dew point in a circulated flow of dry
nitrogen to prevent it from being exposed to the atmosphere.
[0219] Next, a glass substrate, which serves as a sealing substrate
14A, is put in the sealing chamber. The sealing substrate 14A is
provided with a photo-curable resin running along the substrate
edges by a known seal dispenser (not shown).
[0220] The sealing substrate 14A is pressure-bonded to the OLED
substrate 13A in the sealing chamber. A known light-shielding plate
is disposed outside of the sealing substrate 14A to prevent the
whole light-emitting device from being irradiated with ultraviolet
ray, and the resulting assembly is irradiated with UV ray from the
sealing substrate 14A side to cure the photo-curable resin.
[0221] Thus, the organic light-emitting device of Example 1A is
manufactured.
[0222] Example 1A disposes a plurality of the contact holes 12A and
stripe-shape lower reflective electrodes 4A in such a way that the
holes 12 A face each side of the electrode 4A, as illustrate in
FIG. 2A. As a result, the upper transparent electrode 11A is
connected to the metallic substrate 2A of low resistance via the
contact holes 12A, to reduce wiring resistance in the upper
transparent electrode 11A, thereby reducing power consumption
caused by wiring resistance. Moreover, temperature rise caused by
wiring resistance is reduced to suppress deteriorated service life
of the light-emitting element.
Example 2A
[0223] The organic light-emitting device manufactured in Example 2A
is described. FIG. 3A presents a cross-sectional view illustrating
the organic light-emitting device manufactured in Example 2A, and
FIG. 4A presents a plan view illustrating the device illustrated in
FIG. 3A, wherein the component playing the same role as that of the
component described above is marked with the same numeral, and
description of that component is partly omitted. In Example 2A, a
metallic substrate 2A serves as a reflective electrode capable of
reflecting emitted light.
[0224] The metallic substrate 2A is coated with a first interlayer
insulating film 3A on one side and with an insulating film 1A on
the other side, wherein the first interlayer insulating film 3A is
provided with a plurality of stripe-shape contact holes 20A in the
portion facing a lower reflective electrode for the organic
light-emitting element.
[0225] Next, an auxiliary interconnector 21A is disposed on the
first interlayer insulating film 3A, and then a second interlayer
insulating film 6A is disposed thereon. The film 6A is provided
with the auxiliary interconnector 21A and contact holes 12A in the
portion facing a lower reflective electrode for the organic
light-emitting element.
[0226] Next, a hole transporting layer 7A, white-color-emitting
layer 8A, electron transporting layer 9A, electron injection layer
10A and upper transparent electrode 11A are disposed in a manner
similar to that for Example 1A.
[0227] Next, the OLED substrate 13A and sealing substrate 14A are
sealed in a manner similar to that for Example 1A.
[0228] Example 2A electrically connects the upper transparent
electrode 11A and auxiliary interconnector 21A to each other to
reduce wiring resistance in the upper transparent electrode 11A,
thereby reducing power consumption caused by wiring resistance.
Moreover, temperature rise caused by wiring resistance is reduced
to suppress deteriorated service life of the light-emitting
element.
[0229] Moreover, Example 2A uses the metallic substrate 2A as the
lower reflective electrode in the light-emitting element, thereby
simplifying the layered structure, and decreasing the manufacturing
process steps and the production cost.
Example 3A
[0230] The organic light-emitting device manufactured in Example 3A
is described. FIG. 5A presents a cross-sectional view illustrating
the organic light-emitting device manufactured in Example 3A, and
FIG. 6A presents a plan view illustrating the device illustrated in
FIG. 5A, wherein the component playing the same role as that of the
component described above is marked with the same numeral, and
description of that component is partly omitted. Example 3A
disposes a light-emitting element on a composite substrate 31A
provided with an auxiliary interconnector 32A, to simplify the
layered structure.
[0231] The composite substrate 31A has the following structure. It
comprises a metallic substrate 2A coated with a first interlayer
insulating film 3A on one side and with an insulating film 1A on
the other side, the first interlayer insulating film 3A being
provided with a plurality of stripe-shape contact holes, wherein
the metallic substrate 2A portions facing the openings serve as a
lower reflective electrode of the organic light-emitting element.
It also comprises the auxiliary interconnector 32A and a second
interlayer insulating film 6A disposed on the interconnector 32A.
The film 6A is provided with contact holes 12A in the portions
facing the auxiliary interconnector and lower reflective electrode
in the organic light-emitting element.
[0232] Next, a hole transporting layer 7A, white-color-emitting
layer 8A, electron transporting layer 9A, electron injection layer
10A and upper transparent electrode 11A are disposed on the
composite substrate 31A in a manner similar to that for Example
1A.
[0233] Next, the OLED substrate 13A and sealing substrate 14A are
sealed in a manner similar to that for Example 1A.
[0234] Example 3A electrically connects the upper transparent
electrode 11A and auxiliary interconnector 32A to each other to
reduce wiring resistance in the upper transparent electrode 11A,
thereby reducing power consumption caused by wiring resistance.
Moreover, temperature rise caused by wiring resistance is reduced
to suppress deteriorated service life of the OLED element.
[0235] Moreover, Example 3A uses the metallic substrate 2A as the
lower reflective electrode in the light-emitting element, thereby
simplifying the layered structure, and decreasing the manufacturing
process steps and the production cost.
Example 4A
[0236] The organic light-emitting device manufactured in Example 4A
is described. FIG. 7A presents a cross-sectional view illustrating
the organic light-emitting device manufactured in Example 4A, and
FIGS. 8A and 9A present plan views illustrating the device
illustrated in FIG. 7A, wherein the component playing the same role
as that of the component described above is marked with the same
numeral, and description of that component is partly omitted.
Example 4A disposes auxiliary interconnectors 41A in such a way to
arrange the pixels in the organic light-emitting element in a
point-like pattern.
[0237] A metallic substrate 2A is coated with a first interlayer
insulating film 3A on one side and with an insulating film 1A on
the other side. Contact holes 12A and 40A are disposed to surround
each of the lower reflective electrodes 4A arranged in a point-like
pattern. The auxiliary interconnector 41A is disposed on the first
interlayer insulating film 3A.
[0238] The two auxiliary interconnectors 41 are provided on the
left and right sides of the contact holes 12A for each of the lower
reflective electrodes 4A. However, they may be brought together
into a single interconnector by changing their positions.
[0239] Then, a second interlayer insulating film 6A, lower
reflective electrode 4A, connecting electrode 5A and third
interlayer insulating film 42A are disposed on the first interlayer
insulating film 3A in a manner similar to that for Example 1A.
[0240] Next, a hole transporting layer 7A, white-color-emitting
layer 8A, electron transporting layer 9A, electron injection layer
10A and upper transparent electrode 11A are disposed in a manner
similar to that for Example 1A.
[0241] Next, the OLED substrate 13A and sealing substrate 14A are
sealed in a manner similar to that for Example 1A.
[0242] Example 4A electrically connects the upper transparent
electrode 11A and metallic substrate 2A to each other to reduce
wiring resistance in the upper transparent electrode 11A, thereby
reducing power consumption caused by wiring resistance. Moreover,
temperature rise caused by wiring resistance is reduced to suppress
deteriorated service life of the organic light-emitting
element.
[0243] Moreover, Example 4A disposes the auxiliary interconnectors
41A in such a way to arrange the lower reflective electrodes in a
point-like pattern. The contact holes 12A and 40A are disposed
around the lower reflective electrode 4A to connect the upper
transparent electrode 11A and metallic substrate 2A to each other,
thereby further reducing wiring resistance in the upper transparent
electrode 11A.
Example 5A
[0244] The organic light-emitting device manufactured in Example 5A
is described. FIG. 10A presents a cross-sectional view illustrating
the organic light-emitting device manufactured in Example 5A, and
FIGS. 11A and 12A present plan views illustrating the device
illustrated in FIG. 10A, wherein the component playing the same
role as that of the component described above is marked with the
same numeral, and description of that component is partly omitted.
Example 5A connects auxiliary interconnectors 41A running in the
horizontal direction to auxiliary interconnectors 51A running in
the vertical direction, in order to arrange the pixels in the
organic light-emitting element in a point-like pattern.
[0245] A metallic substrate 2A is coated with a first interlayer
insulating film 3A on one side and with an insulating film 1A on
the other side in a manner similar to that for Example 1A. Then,
the auxiliary interconnectors 41A and 51A are disposed on the film
3A. Arrangement of these interconnectors 41A and 51A is illustrated
in FIG. 11A. The interconnector 51A connects the interconnectors
41A in the adjacent lower reflective electrodes 4A right and left.
Example 5A does not continuously connect the interconnectors 51A
from one end to the other end. However, they may be connected from
one end to the other end by changing the contact hole 50A
positions. Example 5A uses the same material for the
interconnectors 41A and 51A. However, they may be made of materials
different from each other.
[0246] Then, a second interlayer insulating film 6A, lower
reflective electrode 4A, connecting electrode 5A and third
interlayer insulating film 42A are disposed on the first interlayer
insulating film 3A in a manner similar to that for Example 1A.
[0247] Next, a hole transporting layer 7A, white-color-emitting
layer 8A, electron transporting layer 9A, electron injection layer
10A and upper transparent electrode 11A are disposed in a manner
similar to that for Example 4A.
[0248] Next, the OLED substrate 13A and sealing substrate 14A are
sealed in a manner similar to that for Example 4A.
[0249] Example 5A electrically connects the upper transparent
electrode 11A and metallic substrate 2A to each other to reduce
wiring resistance in the upper transparent electrode 11A, thereby
reducing power consumption caused by wiring resistance. Moreover,
temperature rise caused by wiring resistance is reduced to suppress
deteriorated service life of the organic light-emitting
element.
[0250] Example 5A disposes the auxiliary interconnectors 41A in
such a way to arrange the pixels in the organic light-emitting
element in a point-like pattern. The contact holes 50A are disposed
between the adjacent lower reflective electrodes 4A one on the
other, to connect the upper transparent electrode 11A and metallic
substrate 2A to each other. This further reduces wiring resistance
in the upper transparent electrode 11A.
[0251] Still more, Example 5A disposes the auxiliary
interconnectors 51A, to further reduce wiring resistance in the
lower reflective electrode 4A.
Example 6A
[0252] The organic light-emitting device manufactured in Example 6A
is described. FIG. 13A presents a cross-sectional view illustrating
the organic light-emitting device manufactured in Example 6A, and
FIGS. 14A and 15A present plan views illustrating the device
illustrated in FIG. 13A, wherein the component playing the same
role as that of the component described above is marked with the
same numeral, and description of that component is partly omitted.
The light-emitting device manufactured in Example 6A is
characterized by the pixels arranged in a matrix pattern.
[0253] A metallic substrate 2A supports a first interlayer
insulating film 3A, lower reflective electrode 4A, connection
electrode 5A, second interlayer insulating film 6A, hole
transporting layer 7A, white-color-emitting layer 8A, electron
transporting layer 9A and electron injection layer 10A on one side,
and is coated with an insulating film 1A on the other side, in a
manner similar to that for Example 4A.
[0254] Next, an upper transparent electrode 11A is disposed on the
electron transporting layer 10A, to cover the lower reflective
electrode 4A and contact holes 12A and 40A, as illustrated in FIG.
15A.
[0255] Example 6A electrically connects the upper transparent
electrode 11A and metallic substrate 2A to each other, to reduce
wiring resistance in the upper transparent electrode 11A, thereby
reducing power consumption caused by wiring resistance. Moreover,
temperature rise caused by wiring resistance is reduced to suppress
deteriorated service life of the organic light-emitting
element.
[0256] Example 5A disposes the upper transparent electrodes 11A in
a stripe pattern, allowing the pixels, in which the upper
transparent electrode 11A intersects with the lower reflective
electrode 4A, to individually emit light. Therefore, the organic
light-emitting device manufactured in Example 6, when used as a
light source for a known liquid-crystalline display device, can
emit light pixel by pixel, thereby reducing power consumption and
improving contrast.
Example 7A
[0257] The organic light-emitting device manufactured in Example 7A
is described. FIG. 16A presents a cross-sectional view illustrating
the organic light-emitting device manufactured in Example 7A, and
FIGS. 17A and 18A present plan views illustrating the device
illustrated in FIG. 16A, wherein the component playing the same
role as that of the component described above is marked with the
same numeral, and description of that component is partly omitted.
Example 7A uses a metallic substrate 2A as a reflective electrode
(lower reflective electrode in the light-emitting element) capable
of reflecting emitted light to simplify the layered structure, and
disposes auxiliary interconnectors for an upper transparent
electrode 11A in a mesh pattern to reduce wiring resistance.
[0258] A metallic substrate 2A supports a first interlayer
insulating film 3A and contact holes 70A disposed in a point-like
pattern on one side, and is coated with an insulating film 1A on
the other side, in a manner similar to that for Example 2A.
[0259] Next, auxiliary interconnectors 21A and 71A are disposed on
the first interlayer insulating film 3A to surround the contact
holes 70A. Example 7A uses the same material for the
interconnectors 21A and 71A. However, they may be made of materials
different from each other. A second interlayer insulating film 6A
and contact holes 12A are disposed on the first interlayer
insulating film 3A in a manner similar to that for Example 2A.
[0260] Next, a hole transporting layer 7A, white-color-emitting
layer 8A, electron transporting layer 9A, electron injection layer
10A and upper transparent electrode 11A are disposed in a manner
similar to that for Example 2A.
[0261] Next, the OLED substrate 13A and sealing substrate 14A are
sealed in a manner similar to that for Example 2A.
[0262] Example 7A electrically connects the upper transparent
electrode 11A to the auxiliary interconnectors 21A and 71A, which
are disposed in a mesh pattern, to reduce wiring resistance in the
upper transparent electrode 11A, thereby reducing power consumption
caused by wiring resistance. Moreover, temperature rise caused by
wiring resistance is reduced to suppress deteriorated service life
of the organic light-emitting element.
[0263] Example 7A uses the metallic substrate 2A as the lower
reflective electrode capable of reflecting emitted light, thereby
simplifying the layered structure, and decreasing the manufacturing
process steps and the production cost.
Example 1B
[0264] Examples (Examples 1B to 7B) for the third embodiment of the
present invention are described by referring to FIGS. 1B, 2B, 5B
and 6B.
[0265] FIG. 1B illustrates process steps for manufacturing an
organic light-emitting element, wherein each of (A), (B), (C), (D)
and (E) presents a cross-sectional view of an organic
light-emitting element structure manufactured in each process step.
FIG. 2B outlines the organic light-emitting element structure which
emits light from the substrate side. FIG. 5B presents a process
flow chart for Example 1B, and FIG. 6B outlines the apparatus
structure for manufacturing the organic light-emitting element in
Example 1B.
[0266] The structure of organic light-emitting element manufactured
in Example 1B is described by referring to FIG. 2B.
[0267] The organic light-emitting element illustrated in FIG. 2B
has a laminated structure with a second electrode 205, hole
transporting layer 204, light-emitting layer 203, electron
transporting layer 202 and first electrode 201, disposed in this
order. It is of bottom emission type in which light emitted from
the light-emitting layer 203 is emitted from the second electrode
205 side, wherein the second electrode 205 and first electrode 201
serve as the respective anode and cathode.
[0268] The second electrode 205 is made of indium tin oxide (ITO),
and can be patterned by photolithography. The anode material for
the second electrode 205 is not limited to ITO, and any material
may be used so long as it has transparency and high work function,
e.g., indium zinc oxide (IZO) and other electroconductive oxides,
and metals of high work function (e.g., thin Ag).
[0269] The hole transporting layer 204 is composed of a layer of
hole injection material and/or layer of hole transporting material.
The hole injection layer is made of poly(3,4-ethylene
dioxythiophene (PEDOT): polystyrene sulfonate (PSS). These
materials are not limited for the hole injection layer. Other
materials useful for the layer include polypyrrole-base and
tirphenylamine-base polymers. Moreover, they may be combined with a
low-molecular-weight compound, and phthalocyanine-base and
starburst-amine-base compounds may be also used. The above layer
may be combined with a layer capable of transferring holes and
blocking electrons. The PEDOT:PSS layer is formed by embrocation,
and baked at 200.degree. C. for 15 minutes. The hole transporting
material layer is disposed between the PEDOT:PSS layer and
light-emitting layer. It is photo-curable with light having a
wavelength longer than that of near-ultraviolet ray. The hole
transporting material is composed of a polymer, cross-linking agent
and photo-polymerization initiator. The useful polymers include
arylamine-base, polyfluorene-base, polyparaphenylene-base,
polyarylene-base and polycarbazole-base ones. The useful
cross-linking agents include oxetane-base, epoxy-base,
vinyl-ether-base compounds. Example 1B uses an arylamine-base
polymer as the polymer, oxetane-base compound as the cross-linking
agent and triallylsulfonium salt as onium salt as the
photo-polymerization initiator.
[0270] The hole transporting material layer is formed by ink
jetting with a solution containing the above compounds. It can be
formed between the hole injection material layer and light-emitting
layer, because a bank is surface-treated to be water-repellent. The
hole transporting material layer is insolubilized by
photo-polymerization, when irradiated with light having a
wavelength longer than that of near-ultraviolet ray. The
photo-polymerization may be carried out in air.
[0271] The hole transporting material is not limited to the
photo-curable material described above. The useful
photo-polymerization initiators include those generate active
radicals or acids, when irradiated with light. Those generate
active radicals include acetophenone-base, benzoin-base,
benzophenone-base, thioxanthone-base and triazine-base
initiators.
[0272] The hole transporting material for the present invention may
be incorporated with a thermal polymerization initiator. The
initiators may be selected from those known as radical
polymerization initiators, including azo compounds, e.g.,
2,2'-azobisbutyronitrile, 2,2-azobis-(2,4-dimethylvaleronitrile),
2,2'-azobis-(4-methoxy-2,4-dimethylvaleronitrile); organic
peroxides, e.g., benzoyl peroxide, lauroly peroxide,
butylperoxypivalate and 1,1'-bis-(t-butylperoxy)cyclohexane; and
hydrogen peroxide.
[0273] The materials useful for the light-emitting layer 203
include polyfluorene-base, polyparaphenylene-base, polyarylene-base
and polycarbazole-base polymers, and so-called dendrimer type
materials having light-emitting and charge transfer functions.
So-called low-molecular-weight compounds may be also used. In such
cases, the host material is preferably a carbazole or fluorene
derivative. The dopant may be of Ir or Pt complex, and is dispersed
in the light-emitting polymer. Example 1B uses a polyfluorene-base
polymer for the light-emitting layer 203. The light-emitting layer
203 can be selectively disposed on the hole transporting layer 204,
when formed by ink jetting with a solution, because the bank is
kept water-repellent.
[0274] The applicable wet processes include ink jetting, printing
and spraying. The useful solvents include mixed polar solvents,
e.g., those of aromatic-base and alcohol-base solvents. It is
needless to say that aromatic-base and alcohol-base solvents can be
used individually. The solution (ink) preferably has a viscosity of
1 to 20 mPas at room temperature, when ink jetting is used. The
solid concentration in the solution is not limited, so long as the
solution gives a desired layer thickness.
[0275] The electron transporting 202 works to provide electrons to
the light-emitting layer 203. Example 1B forms the layer
light-emitting layer 202 by vacuum deposition using
bis(2-methyl-8-quinolinate)-4-(phenylphenolate) aluminum (BAlq).
However, the compound for the layer 202 is not limited to BAlq. The
other useful compounds include tris(8-quinolinolate) aluminum
derivatives, oxadiazole derivatives, triaszole derivatives,
fllerene derivatives, phenanthroline derivatives and quinoline
derivatives.
[0276] Example 1B uses a laminate of LiF and Al for the first
electrode 201. The materials useful for the electrode 201 are not
limited to them. Examples of the other useful materials include
electron transporting materials other than LiF (e.g., Cs, Ba and Ca
compounds) co-deposited with an alkaline metal (e.g., Li or Cs),
alkaline-earth metal or electron donating organic compound.
[0277] The method for manufacturing the organic light-emitting
element of the present invention is described by referring to FIG.
1B.
[0278] Example 1B uses a first organic compound 105B for the hole
transporting layer 204 and light-emitting layer 203, illustrated in
FIG. 2B, and second organic compound 106B for the electron
transporting layer 202, illustrated in FIG. 2B.
[0279] FIG. 1B (A) illustrates a process step for forming a second
electrode 1038 and diaphragm 104B.
[0280] A TFT-containing layer 102B is composed of an insulating
film covering a substrate 101B, TFT, drain and source electrodes in
the TFT, and insulating film for protecting the drain and source
electrodes. After the TFT-containing layer 1028 is formed, a second
electrode 103B is formed, wherein the electrode 103B is
electrically connected to the drain electrode or source electrode
in the TFT-containing layer 102B. Then, the diaphragm 104B is
formed to cover the second electrode 103B edges.
[0281] The material for the diaphragm 1048 is not limited. The
useful materials include various resins, e.g., polyimide and
acrylic resins. Example 1B uses a photo-sensitive polyimide resin.
The diaphragm 104B may be formed by embrocation, and lithographic
exposure and development with a given photo-mask. The bank is
surface-treated to be water-repellent. For example, the surface is
fluorinated with plasma of fluorine-base gas.
[0282] The diaphragm 104B may contain carbon to take on black color
to absorb more heat in the subsequent step of heating under a
vacuum. The black-color source is not limited to carbon, so long as
the diaphragm 104 takes on black color.
[0283] FIG. 1B (B) illustrates a process step for forming the first
organic compound 105B containing the light-emitting layer. The
first organic compound 105B formed in Example 1B is used for the
hole transporting layer 204 and light-emitting layer 203. The
compound 105B is formed on the second electrode 103B by
embrocation.
[0284] FIG. 1B (C) illustrates a step of heating under a vacuum
(10.sup.-4 Pa or less) to remove moisture from the first organic
compound 105B. The devices for securing the above degree of vacuum
include, but not limited to, cryo-pump, turbo molecular pump and
ion pump. Any type of pump may be used so long as it can secure the
above degree of vacuum. Example 1B uses a planar heat generator
(so-called hot plate type heat generator) as the heating apparatus
108B for the vacuum heating step. The heating apparatus 108B is
disposed on the substrate 101B side to be in contact with the
substrate 101B.
[0285] The degree of vacuum is preferably as close to 0 Pa as
possible. However, it is preferably 10.sup.-7 Pa or more in
consideration of the commercialized techniques.
[0286] The heating apparatus 108B heats the substrate 101B, and the
first organic compound 105B to 70 to 100.degree. C. Moisture is
removed from the first organic compound 105B which is heated by the
heating apparatus 108B in a vacuum chamber kept at 10.sup.-4
Pa.
[0287] Test results indicate that heating at 70.degree. C. under a
vacuum is more effective for prolonging service life of the element
than at 50.degree. C. Removal of moisture is observed at 80.degree.
C. and substantially completed at 100.degree. C., as revealed by
TDS analysis. It is considered that moisture is removed from the
first organic compound 105B when it is heated at 70 to 100.degree.
C. under a vacuum. The upper temperature limit is set at
100.degree. C., because the film may be deteriorated at a higher
temperature, depending on organic compound that constitutes the
film.
[0288] FIG. 1B (D) illustrates a step for forming a layer
containing the second organic compound 106B.
[0289] The second organic compound 106B formed in Example 1B is the
electron transporting layer 202, illustrated in FIG. 2.
[0290] The layer containing the second organic compound 106B is
formed on the layer containing the first organic compound 105B,
thermally treated under a vacuum to remove moisture, by vacuum
deposition. The degree of vacuum is kept at 10.sup.-4 Pa or less
also in this step. The devices for securing the above degree of
vacuum include, but not limited to, cryo-pump, turbo molecular pump
and ion pump. Any type of pump may be used so long as it can secure
the above degree of vacuum.
[0291] FIG. 1B (E) illustrates a step for forming a first electrode
107B.
[0292] The first electrode 107B is formed on the layer containing
the second organic compound 106B under a vacuum of 10.sup.-4 Pa or
less. The devices for securing the above degree of vacuum include,
but not limited to, cryo-pump, turbo molecular pump and ion pump.
Any type of pump may be used so long as it can secure the above
degree of vacuum.
[0293] Degree of vacuum is kept at 10.sup.-4 Pa or less from the
heating step, illustrated in FIG. 1B (C), to the first electrode
forming step, illustrated in FIG. 1B (E). A transfer step is
provided from one step to the subsequent one. Degree of vacuum is
kept at 10.sup.-4 Pa or less also in the transfer step.
[0294] The devices for securing the above degree of vacuum include,
but not limited to, cryo-pump, turbo molecular pump and ion pump.
Any type of pump may be used so long as it can secure the above
degree of vacuum.
[0295] FIG. 5B presents a flow chart of the process steps used in
Example 1B. The substrate 101B is transferred from an embrocation
chamber 501 for forming the first organic compound 105B to a vacuum
chamber 502 for heating the first organic compound 105B under a
vacuum, vacuum deposition chamber 503 for forming the second
organic compound 106B by vacuum deposition, chamber 504 for forming
the first electrode 107B and sealing chamber 505 for keeping the
manufactured organic light-emitting element unexposed to the
atmosphere, in this order. The first electrode 107B is formed by
resistance heating or sputtering in the chamber 504. FIG. 6B
outlines the apparatus structure for manufacturing the organic
light-emitting element in Example 1B. It comprises an embrocation
chamber 601, vacuum chamber 602 for heating under a vacuum, vacuum
deposition chamber 603, chamber 604 for forming the first
electrode, sealing chamber 605 and transfer chamber 606. Each
chamber forms a closed space by a door, and is completely
independent from the others.
[0296] The substrate 101B is coated with the first organic compound
105B in the embrocation chamber 601 by an embrocation method, and
is transferred to the transfer chamber 606 in an inert atmosphere
having a dew point of -90.degree. C. or higher (corresponding to a
moisture content of about 100 ppb or less) of the embrocation
chamber 601 and the transfer chamber 606 in the one-way direction
to prevent a back flow of from the transfer chamber 606 to the
embrocation chamber 601. The doors in the chambers 601 and 606 are
closed after the coated substrate 101B is transferred into the
chamber 606. The chamber 606 is kept at a vacuum of 10.sup.-4 Pa or
less by a vacuum pump (e.g., cryo-pump, turbo molecular pump, ion
pump or the like). Any type of pump may be used so long as it can
secure the above degree of vacuum. Then, the coated substrate 101B
is transferred from the transfer chamber 606 to the vacuum heat
chamber 602, where it is heated under a vacuum of 10.sup.-4 Pa or
less in the vacuum heat chamber 602. The vacuum heat chamber 602 is
equipped with a planar heat generator (so-called hot plate type
heating apparatus). The planar heat generator has a wider area than
the substrate 101B, to uniformly heat the substrate 101B at from
70.degree. C. to 100.degree. C., preferably at 100.degree. C.
[0297] The coated substrate 101B is heated at 100.degree. C. for 30
minutes, and then cooled for 30 minutes.
[0298] The chamber 602 is kept at a vacuum of 10.sup.-4 Pa or less
by a vacuum pump, e.g., cryo-pump, turbo molecular pump, ion pump
or the like.
[0299] The coated substrate 101B treated in the chamber 602 is
transferred back to the chamber 606, which is kept at a vacuum of
10.sup.-4 Pa or less. It is then transferred from the chamber 606
to the chamber 603, where it is coated with the second organic
compound 106 by vacuum deposition. It is then transferred back to
the chamber 606, and from the chamber 606 to the chamber 604, where
it is coated with the first electrode 107B to have the organic
light-emitting element. The element is transferred back to the
chamber 606, and then to the chamber 605, where it is kept
unexposed to the atmosphere.
[0300] The apparatus used in Example 1B for manufacturing the
organic light-emitting element has a structure of so-called cluster
type. It transfers the coated substrate 101B to each of the
chambers via a single transfer chamber. The transfer chamber 606 is
equipped with an arm for supporting the coated substrate 101B. The
apparatus structure including the transfer chamber 606 is not
limited to the one illustrated in FIG. 6B which only outlines the
structure. The chamber 606 has doors each opening for transferring
the coated substrate 101B to a specific chamber and bringing it
back from that chamber. It closes the door after receiving the
coated substrate 101B. The coated substrate 101B is then rotated
and moved, and transferred to the subsequent chamber.
[0301] The apparatus may have the two or more transfer chambers 606
for various reasons, e.g., locations of the chambers 601, 602, 603,
604 and 605, distance between the adjacent chambers and layout of
the chambers. Even in such a case, each of the transfer chambers
606 must be kept at 10.sup.-4 Pa or less.
[0302] The method and apparatus of Example 1B can conveniently
manufacture the light-emitting layer by embrocation, and organic
light-emitting element of prolonged service life.
[0303] The method and apparatus of Example 1B can remove moisture
from the light-emitting layer to manufacture the organic
light-emitting element of prolonged service life. The organic
light-emitting element manufactured by the present invention
described in Example 1B can find wide applicable areas, e.g.,
active-matrix or passive-matrix organic light-emitting display
devices, back lights for LCD panels, and various illuminators.
Example 2B
[0304] Example 2B is described by referring to FIGS. 1B, 3B, 5B and
6B.
[0305] FIG. 3B outlines the organic light-emitting element
structure manufactured in Example 2B. The element manufactured in
Example 2B differs from that manufactured in Example 1B in that a
second electrode 305 and first electrode 301 illustrated in FIG. 3B
serve as the respective reflective electrode and transparent
electrode.
[0306] The organic light-emitting element illustrated in FIG. 3B
has a laminated structure with a second electrode 305, hole
transporting layer 304, light-emitting layer 303, electron
transporting layer 302 and first electrode 301, disposed in this
order. It is of top emission type in which light emitted from the
light-emitting layer 303 is emitted from the first electrode 301
side, wherein the second electrode 305 and first electrode 301
serve as the respective anode and cathode. The light-emitting
element is manufactured in a manner similar to that for Example 1B,
by the method illustrated in FIG. 1B, process flow illustrated in
FIG. 5B and apparatus illustrated in FIG. 6B. The hole transporting
layer 304 and light-emitting layer 303 are of the first organic
compound 105B, and the electron transporting layer 302 is of the
second organic compound 106B. The hole transporting layer 304 and
light-emitting layer 303 are manufactured by embrocation, and the
electron transporting layer 302 by vacuum deposition.
[0307] The second electrode 305 has a laminated structure with Al
and ITO. Other materials useful for the second electrode 305
include Cr, Ag, Al and laminates of these metals with IZO. It is
manufactured by treating the thin film of the above material(s) by
photolithography or the like.
[0308] The first electrode 301 is made of In--Zn--O (IZO) film. The
first electrode material is not limited to IZO, needless to say.
Any material may be used so long as it is highly light-permeable.
For example, it may be made of transparent ITO or ZnO, or Cr, Ag or
the like formed into a thin film. The first electrode 301 is
manufactured by resistance heating or sputtering.
[0309] The substrate 101B, after being coated with the
light-emitting layer 303, is transferred from the chamber 602
eventually to the chamber 604 illustrated in FIG. 6, all of the
chambers being kept at 10.sup.-4 Pa or less.
[0310] The organic light-emitting element is manufactured in
Example 2B following the process flow chart illustrated in FIG. 5B
and by the apparatus illustrated in FIG. 6B, in which the coated
substrate 101B is transferred from one chamber to the subsequent
one, both of these figures being described in Example 1B.
[0311] The method and apparatus used in Example 2B can conveniently
manufacture the light-emitting layer by embrocation, and organic
light-emitting element of prolonged service life, the element being
of so-called top emission type. A top-emission type element gives
an organic light-emitting display device of higher aperture ratio.
Therefore, it can operate at a lower brightness, which leads to a
longer service life.
[0312] The method and apparatus used in Example 2B can remove
moisture from the light-emitting layer to manufacture the organic
light-emitting element of prolonged service life. The organic
light-emitting element manufactured in Example 2B can find wide
applicable areas, e.g., actively or passively driven organic
light-emitting display devices, back lights for liquid-crystalline
panels, and various illuminators.
Example 3B
[0313] Example 3B is described by referring to FIGS. 1B, 4B, 5B and
6B.
[0314] FIG. 4B outlines the organic light-emitting element
structure manufactured in Example 3B. The element manufactured in
Example 3B differs from that manufactured in Example 2B in that it
has a different organic compound disposed between a second
electrode 405 and first electrode 401. The element manufactured in
Example 3B has a laminated structure with a second electrode 405,
electron transporting layer 404, light-emitting layer 403, hole
transporting layer 402, hole injection layer 406 and first
electrode 401. It is of top emission type in which light emitted
from the light-emitting layer 403 is emitted from the first
electrode 401 side, wherein the second electrode 405 is reflective
and first electrode 401 is transparent. The hole injection layer
406, manufactured by vacuum deposition, is made of a metallic oxide
capable of efficiently injecting holes transferred from the first,
transparent electrode 401. The metallic oxide is selected from
those of molybdenum, ruthenium, aluminum, bismuth, gallium,
germanium, magnesium, antimony, silicon, titanium, tungsten,
yttrium, zirconium, iridium, rhenium and vanadium, having a work
function of 5.5 eV or more.
[0315] The second electrode 405 is made of an AlNi alloy. The
material useful for the electrode is not limited to the alloy.
Other materials useful for the second electrode 405 include Al,
AlNd alloy, AlSi alloy and Al/ITO laminate. It is manufactured by
treating the thin film of the above material(s) by photolithography
or the like.
[0316] The electron transporting layer 404 and light-emitting layer
403 are of the first organic compound 105B, and the hole
transporting layer 402 and hole injection layer 406 are of the
second organic compound 106B. The electron transporting layer 404
and light-emitting layer 403 are manufactured by embrocation, and
the hole transporting layer 402 and hole injection layer 406 by
vacuum deposition.
[0317] The first electrode 401 is made of In--Zn--O (IZO) film. The
first electrode material is not limited to IZO. Any material may be
used so long as it is highly light-permeable. For example, it may
be made of transparent ITO or ZnO, or Cr, Ag or the like formed
into a thin film. The first electrode 301 is manufactured by
resistance heating or sputtering. The substrate 1018, after being
coated with the light-emitting layer 403, is transferred from the
chamber 606 eventually to chamber 604 illustrated in FIG. 6B, all
of the chambers being kept at 10.sup.-4 Pa or less.
[0318] The organic light-emitting element is manufactured in
Example 3B following the process flow chart illustrated in FIG. 5B
and by the apparatus illustrated in FIG. 6B, in which the coated
substrate 101B is transferred from one chamber to the subsequent
one, both of these figures being described in Example 1B.
[0319] The method and apparatus used in Example 3B can conveniently
manufacture the light-emitting layer by embrocation, and organic
light-emitting element of prolonged service life, the element being
of so-called top emission type. A top-emission type element gives
an organic light-emitting display device of higher aperture ratio.
Therefore, it can operate at a lower brightness, which leads to a
longer service life. Moreover, Example 3B uses the metallic oxide
capable of efficiently injecting holes transferred from the anode,
thereby manufacturing the organic light-emitting element of high
efficiency.
[0320] The method and apparatus used in Example 3B can remove
moisture from the light-emitting layer to manufacture the organic
light-emitting element of prolonged service life. The organic
light-emitting element manufactured in Example 3B can find wide
applicable areas, e.g., actively or passively driven organic
light-emitting display devices, back lights for liquid-crystalline
panels, and various illuminators.
Example 4B
[0321] Example 4B is described by referring to FIGS. 1B, 5B, 6B and
7B.
[0322] Example 4B uses the same method and apparatus for
manufacturing the organic light-emitting elements having the
structure described in Examples 18 to 3B, except that a
high-frequency dielectric device is disposed as the heating
apparatus in the vacuum chamber 502 for heating the substrate under
a vacuum. A vacuum chamber 701 used in Example 4B is illustrated in
FIG. 7B which outlines a structure as one example of the process
step illustrated in FIG. 1B (C), wherein 701A and 701B are
respective plan and side views of the chamber. A substrate 702
contains the first organic compound 105 shown in FIG. 1B (C). The
high-frequency dielectric device 703 is disposed below the
substrate 702 (on the substrate 101B side in FIG. 1B), to heat the
second electrode 103B in the substrate 702. The position of the
device 703 is not limited to the one described above. The two or
more devices 703 may be disposed on the first electrode 107B side,
shown in FIG. 1 (E), to hold the substrate 101B in-between in the
vertical direction. Moreover, the device 703 may be disposed to
surround the substrate 702 to form a tunnel.
[0323] The high-frequency dielectric device 703 is at least as wide
as the substrate 702 both in the substrate travel direction and the
direction perpendicular to the travel direction. The substrate 702
travels in such a way to totally uniformly heat the second
electrode 103B in the substrate 702. The substrate 702 travels to
the right side, and the transfer chamber is positioned to the left
side of the vacuum chamber in Example 4B, as shown in FIG. 7B.
[0324] The high-frequency dielectric device 703, which is disposed
to heat the second electrode 103B, is not limited for its width in
the longitudinal direction, so long as it uniformly heats the
second electrode 103B in the substrate 101B.
[0325] The high-frequency dielectric device 703 used in Example 4B
heats the second electrode 103B by the Joule heat generated by eddy
current evolving in a conductor disposed in a high-frequency
electromagnetic field, the heat being in proportion to the
conductor surface skin resistance Rs. The Rs is given by the
formula Rs=.rho./.delta.=(.omega..mu..rho./2).sup.1/2, wherein
.omega. is angular frequency, .mu. is permeability, .rho. is
specific resistance and .delta. is the skin
depth=((2.rho./.omega..mu.).sup.1/2).
[0326] Power P generated in the conductor is represented by the
formula P.varies.R.intg.|I|.sup.2ds, wherein I is current flowing
in the conductor. The heat can be increased by increasing frequency
.omega., and by using a material of high permeability .mu. and
specific resistance .rho..
[0327] The high-frequency dielectric device 703 generates an
electromagnetic wave having a frequency of about 60 to 90 kHz to
heat the second electrode 103B. The second electrode 103B can be
easily heated, because it is sufficiently thin (thickness: 100 to
300 nm) and has a high resistance. As illustrated in FIG. 7B, the
substrate 702 is thoroughly heated uniformly while traveling in the
chamber. The second electrode 103B is heated at 70 to 100.degree.
C., preferably at 100.degree. C. Moisture can be removed in a short
time from the first organic compound 105B containing the
light-emitting layer by the heat from the second electrode 103B,
which is disposed immediately below the compound 105B. Moreover,
the cooling period can be shortened, because the substrate 702 is
not totally heated.
[0328] The high-frequency dielectric device 703 is disposed at
around the vacuum chamber 701 center in FIG. 7B. However, the
position of the device 703 is not limited to the above. It may be
located anywhere, so long as it can uniformly heat the substrate
702. For example, it may be located on the transfer chamber side in
the chamber 701, or on the doorway side of the substrate 702 in the
chamber 701 (left side in FIG. 7B). The substrate 702 is
transferred from the transfer chamber 606 to the vacuum chamber 701
while these chambers are kept at 10.sup.-4 Pa or less. The second
electrode 103B may be heated while the substrate 702 is transferred
from the transfer chamber 606 to the vacuum chamber 701.
[0329] The high-frequency dielectric device 703 generates an
electromagnetic wave having a frequency of about 60 to 90 kHz while
overlapping the second electrode 103B in the substrate 702 to heat
the second electrode 103B in a very short time, thereby removing
moisture from the first organic compound 105B containing the
light-emitting layer. The heating under a vacuum preferably lasts 1
minute or more for the structure manufactured in Example 4B.
[0330] Example 4B manufactures the organic light-emitting element
following the process flow chart illustrated in FIG. 5B and by the
apparatus illustrated in FIG. 6B for manufacturing the organic
light-emitting elements in Examples 1B to 3B, in which the coated
substrate 101B is transferred from one chamber to the subsequent
one, both of these figures being described in Example 1B.
[0331] The method and apparatus used in Example 4B can conveniently
manufacture the light-emitting layer by embrocation, and organic
light-emitting element of prolonged service life.
[0332] The high-frequency dielectric device 703 used in Example 4B
selectively heats the second electrode 103B while not heating the
whole substrate 702, thereby shortening the heating time and
cooling time, and hence improving productivity.
[0333] The method and apparatus used in Example 4B can remove
moisture from the light-emitting layer to manufacture the organic
light-emitting element of prolonged service life. The organic
light-emitting element manufactured in Example 4B can find wide
applicable areas, e.g., actively or passively driven organic
light-emitting display devices, back lights for liquid-crystalline
panels, and various illuminators.
Example 5B
[0334] Example 5B is described by referring to FIGS. 1B, 8B and
9B.
[0335] Example 5B uses the same method and apparatus described in
Example 4B for manufacturing the organic light-emitting elements
having the structure described in Examples 1B to 3B, except that a
high-frequency dielectric device is disposed at a different
location. FIG. 8B outlines the light-emitting element structure
manufactured in Example 5B. FIG. 9B outlines an apparatus structure
used in Example 5B for manufacturing an organic light-emitting
element. In Examples 5B, a high-frequency dielectric device 803 is
disposed in a transfer chamber 801. FIG. 8B outlines one example of
the vacuum heating step of FIG. 1B(C). The transfer chambers 801A
and 801B are respective plan and side views of the transfer
chamber. A substrate 802 contains the first organic compound 105B
illustrated in FIG. 1B (C). The substrate 802 is transferred from
an embrocation chamber 901 to a vacuum deposition chamber 902
invariably via the transfer chamber 801, in which the
high-frequency dielectric device 803 is disposed. The device 803
may be disposed on the side of doorway for transferring the
substrate 802, as with the case in Example 4B. In FIG. 8B, the
substrate 802 travels to the right side, and each chamber is
disposed on the left side.
[0336] An apparatus structure used in Example 5B for manufacturing
an organic light-emitting element is outlined by referring to FIG.
9B. The substrate 802 is transferred from the embrocation chamber
901 to the transfer chamber 801, where it is heated under a vacuum.
The substrate 802 treated in the transfer chamber 801 is then
transferred to the vacuum deposition chamber 902. The subsequent
steps are the same as those used in Example 1B.
[0337] The method and apparatus used in Example 5B can conveniently
manufacture the light-emitting layer by embrocation, and organic
light-emitting element of prolonged service life.
[0338] The apparatus for manufacturing an organic light-emitting
element, having the structure described in Example 5B, needs no
chamber for heating the substrate under a vacuum, thereby saving
the space. The apparatus described in Example 5B completes the
heating and cooling steps in a shorter time than those described in
Examples 1B to 3B. The organic light-emitting element manufactured
in Example 5B can find wide applicable areas, e.g., actively or
passively driven organic light-emitting display devices, back
lights for liquid-crystalline panels, and various illuminators.
Example 6B
[0339] Example 6B is described by referring to FIGS. 1B, 9B and
10B.
[0340] Example 6B uses the same method and apparatus described in
Example 5B for manufacturing the organic light-emitting elements
having the structure described in Examples 1B to 3B, except that a
high-frequency dielectric device is disposed in another chamber.
FIG. 10B outlines the vacuum deposition chamber 1001 structure, in
which the high-frequency dielectric device 1003 is disposed. The
device 1003 may be disposed in the chamber 1001 on the side of
doorway for transferring a substrate 1002, as with the cases in
Examples 4B and 5B, or at the interface between the transfer
chamber 801 and vacuum deposition chamber 902. In FIG. 10B, the
substrate 1002 travels to the right side, and the transfer chamber
is disposed on the left side.
[0341] An apparatus structure used in Example 5B for manufacturing
an organic light-emitting element is outlined by referring to FIG.
9B. The substrate 1002 is transferred from an embrocation chamber
901 to the transfer chamber 801, and then from the chamber 801 to
the vacuum deposition chamber 902, where it is heated under a
vacuum, as illustrated in FIG. 1B (C). The heated substrate 1002 is
then coated with the second organic compound 106B in the chamber
902 by vacuum deposition, and transferred back to the transfer
chamber 801. The subsequent steps are the same as those used in
Example 1B.
[0342] The method and apparatus used in Example 6B can conveniently
manufacture the light-emitting layer by embrocation, and organic
light-emitting element of prolonged service life.
[0343] The apparatus having the structure described in Example 6B
needs no chamber for heating the substrate under a vacuum, thereby
saving the space. It can complete the heating and cooling steps in
a shorter time than those described in Examples 1B to 3B. Moreover,
it can remove moisture from the light-emitting layer to give an
organic light-emitting element of prolonged service time.
[0344] The organic light-emitting element manufactured in Example
6B can find wide applicable areas, e.g., actively or passively
driven organic light-emitting display devices, back lights for
liquid-crystalline panels, and various illuminators.
Example 7B
[0345] The method and apparatus used in Example 7B are
characterized in that the high-frequency dielectric device used in
Examples 4B to 6B is replaced by a microwave generator for the
chamber for heating a substrate under a vacuum. They are the same
as those used in Examples 4B to 6B, except for the above. The
microwave generator can heat the first organic compound 105 under a
vacuum to remove moisture from the compound. It preferably outputs
0.1 to 1.5 kW for 1 minute or more.
[0346] The method and apparatus used in Example 7B can conveniently
manufacture the light-emitting layer by embrocation, and organic
light-emitting element of prolonged service life.
[0347] The apparatus described in Example 7B with the microwave
generator can complete the heating and cooling steps in a shorter
time, because the generator does not totally heat the substrate
101B, thereby improving productivity. Moreover, it can remove
moisture from the light-emitting layer to give an organic
light-emitting element of prolonged service time. The organic
light-emitting element manufactured in Example 7B can find wide
applicable areas, e.g., actively or passively driven organic
light-emitting display devices, back lights for liquid-crystalline
panels, and various illuminators.
[0348] In relation to the present invention, the following
technical matters are disclosed.
* * * * *