JPH10223375A - Organic el element and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic EL element capable of high-dignity light emission display by providing an insulator formed on substantially the same plane as a transparent electrode surface, a rear electrode formed opposite to the transparent electrode between the transparent electrodes formed with given intervals on a transparent substrate surface and a light emitting layer of organic EL material between the transparent electrode and the rear electrode. SOLUTION: A transparent electrode material 11 such as ITO is adhered to a surface of a transparent substrate 10 such as glass, quartz, transparent resin or the like, a photo resist 16 is applied, a transparent electrode 12 formed with a given interval is left, and the transparent electrode material 11 is removed. An insulator 14 is fully adhered and polished so that a surface transparent electrode 12 and the insulator is on the same plane. A luminous layer consisting of an organic EL material is laminated on the same surface, and a rear electrode of a stripe pattern is formed by mask evaporation. Thereby, the EL element is formed in the stripe shape and on the same plane of the transparent electrode 12 and the insulator 14, the transparent electrode 12 and the rear electrode are insulated, and certain dot light emission is made possible without generating short-circuit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat light source, a display, and an organic EL element used for light emission display of a predetermined pattern, and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, for example, an organic EL (electroluminescence) element which emits a dot matrix has a light-transmitting ITO film formed on a glass substrate on one surface thereof.
The film is etched into stripes to form transparent electrodes,
A hole transport material such as a triphenylamine derivative (TPD) is provided on the surface thereof, and an electron transport material such as an aluminum chelate complex (Alq ₃ ) as a light emitting material is laminated thereon. And, on the surface, Al, Li, Ag, Mg, In
And the like are formed by vapor deposition or the like attached in a stripe shape in a direction orthogonal to the pattern of the transparent electrode. In this organic organic EL element, a predetermined current is applied to the intersection of a transparent electrode and a back electrode to emit light. In the production of the organic EL device, the above-mentioned electrode material and EL material are sequentially formed on a glass substrate by vacuum deposition.

[0003]

Here, the organic EL element is an element through which a current flows. In order to prevent the amount of light emission from being different from the difference in resistance due to the difference in the conductor path length, the organic EL element must It was necessary to minimize the resistance of the path. Therefore, for that purpose, the thickness of the ITO film must be
About 1 μm is required. on the other hand. If the material of the light emitting layer is thick, no current flows, so that both TPD and Alq ₃ have a thickness of 50%.
It is formed in a thin layer of about 0 °.

[0004] Therefore, since the difference between the thickness of the transparent electrode and the thickness of the light emitting layer is extremely large, the step cannot be completely covered by deposition of the EL material or the like. Some thin or missing parts of the material
In some cases, a short circuit occurred between the back electrode and the transparent electrode, resulting in a portion that did not emit light.

SUMMARY OF THE INVENTION The present invention has been made in view of the above conventional technology, and has an organic EL element capable of performing high-quality light-emitting display with a simple configuration, without causing a short circuit between a back electrode and a transparent electrode. It is an object of the present invention to provide a manufacturing method thereof.

[0006]

SUMMARY OF THE INVENTION The present invention provides a transparent electrode in which a transparent electrode material such as ITO is formed on a transparent substrate surface such as glass, quartz or resin at a predetermined interval, and a portion between the transparent electrodes. An insulator formed substantially flush with the surface of the transparent electrode, a back electrode formed facing the transparent electrode, a hole transport material and an electron provided between the transparent electrode and the back electrode. An organic EL device comprising a transport material and a light emitting layer made of an organic EL material made of a light emitting material. Further, an insulator and a conductor are provided in a portion between the transparent electrodes, respectively, and the insulator and the conductor are formed flush with the transparent electrode. In addition, the transparent electrode is formed in a wide portion and a narrow portion, and the space between them is insulated by an insulator having a relatively narrow predetermined width,
A conductor is provided at a portion between the transparent electrodes opposite to the insulator with the narrow portion of the transparent electrode interposed therebetween, and the surfaces of the insulator and the conductor are formed flush with the surface of the transparent electrode. Is what it is.

Further, according to the present invention, a transparent electrode material such as ITO is adhered all over the surface of a transparent substrate made of glass, quartz, transparent resin or the like by a vacuum thin film forming technique such as vapor deposition, and a photoresist is applied to the surface. Then, a transparent electrode pattern is formed at a predetermined interval using a photomask, the transparent electrode material is removed while leaving the transparent electrode pattern, and thereafter, an insulator is deposited on a portion where the electrode material is removed. Etc., and the surface thereof is treated by polishing or the like so that the transparent electrode and the insulator portion are substantially flush with each other, and the hole transport material and the electron transport are applied to the substantially flush surface. An organic EL device in which a light emitting layer made of an organic EL material made of a material or other light emitting material is laminated by a vacuum thin film forming technique, and a back electrode is formed by a vacuum thin film forming technique.
This is a method for manufacturing an element.

Further, according to the present invention, a transparent electrode material such as ITO is adhered to the entire surface of a transparent substrate similar to the above by a vacuum thin film forming technique such as vapor deposition, a photoresist is applied to the surface, and a photomask is formed. A transparent electrode pattern is formed at a predetermined interval using the transparent electrode material, leaving the transparent electrode pattern, and then removing the electrode material from the transparent electrode. An insulator was deposited by a vacuum thin film forming technique such as vapor deposition from a predetermined oblique direction having a component perpendicular to the longitudinal direction of the transparent electrode, and thereafter, the component had a component substantially opposite to the direction in which the insulator was deposited. A conductor is adhered from an oblique direction by a vacuum thin film forming technique such as vapor deposition, and then the surfaces are polished by polishing or the like so that the transparent electrode, the insulator, and the conductor portion are substantially flush with each other. Management, and this almost hole flush surface transport material and electron transport material other luminescent material with an organic E
This is a method of manufacturing an organic EL device in which a light emitting layer made of L material is laminated by a vacuum thin film forming technique, and a back electrode is formed by a vacuum thin film forming technique.

The present invention also provides a method for forming a transparent electrode material such as ITO on one surface of a transparent substrate by a vacuum thin film forming technique such as vapor deposition, and applying a photoresist on the surface to form a photomask. Using the transparent electrode material, a predetermined pattern is formed so as to form a transparent electrode in which a wide portion and a narrow portion having a predetermined width are alternately formed, and the transparent electrode material is formed between the wide portion and the narrow portion of the transparent electrode. An insulator is attached to a relatively narrow portion by masking by a vacuum thin film forming technique such as evaporation by masking, and before or after this, a relatively wide portion between the wide portion and the narrow portion of the transparent electrode is formed. A conductor is attached by masking a vacuum thin film forming technique such as evaporation between the transparent electrodes between the transparent electrodes, and then these surfaces are surfaced so that the transparent electrode, the insulator, and the conductor portion are substantially flush with each other. By polishing Management, and this almost hole flush surface transport material and electron transport material other luminescent material with an organic E
This is a method of manufacturing an organic EL device in which a light emitting layer made of L material is laminated by a vacuum thin film forming technique, and a back electrode is formed by a vacuum thin film forming technique.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. 1 (A) to 1 (D)
1 shows a first embodiment of the organic EL device of the present invention. The organic EL device of this embodiment has a transparent electrode material 11 such as ITO on one side of a transparent substrate 10 made of glass, quartz, resin or the like. Is formed. The transparent electrode 12 has a thickness of about 1 μm and is formed on the stripe at a predetermined pitch.
It is formed on a transparent electrode 12 having a width of m. Between the transparent electrodes 12, an insulator 14 such as SiO ₂ is formed on the stripe with a thickness of about 1 μm and a width of 0.5 mm. Therefore, the surfaces of the transparent electrode 12 and the insulator 14 are located on the same plane and are formed flush.

On the surfaces of the transparent electrode 12 and the insulator 14, 5
A light emitting layer (not shown) made of an organic EL material using a hole transporting material of about 00 °, an electron transporting material of about 500 ° and other light emitting materials is laminated. Then, for example, 0.01 to 0.05% of Li is applied to the surface of the electron transporting material of the light emitting layer.
A back electrode of an Al-Li alloy having a purity of about 99% is formed in a stripe shape with a predetermined pitch in a direction perpendicular to and facing the transparent electrode 12 with an appropriate thickness of about 500 ° to 1000 °.

Further, the surface of this back electrode is appropriately
A conductive pattern made of Al or the like having a purity of 9.999% or more is formed in a stripe shape. On this surface, a protective layer (not shown) is further laminated. The protective layer is formed of a metal thin film such as Ag or Al, a resin such as phenol or epoxy, or a conductive paint, and shields the back electrode and the light emitting layer from the outside air.

In the light emitting layer, as a hole transporting material among the base materials, there are a triphenylamine derivative (TPD), a hydrazone derivative, an arylamine derivative and the like. Also,
As electron transport materials, aluminum chelate complexes (Al
q ₃ ), distyrylbiphenyl derivatives (DPVBi),
An oxadiazole derivative, a bistyrylanthracene derivative, a benzoxazolethiophene derivative, perylenes, thiazoles, or the like is used. Further, an appropriate light emitting material may be mixed, or a light emitting layer in which a hole transport material and an electron transport material are mixed may be formed. In this case, the ratio of the hole transport material to the electron transport material is from 10:90 to 90:10
Can be changed as appropriate within the range.

As shown in FIG. 1A, the manufacturing method of the EL element of this embodiment is to form an ITO film on a surface of a transparent substrate 10 made of glass, quartz, transparent resin or the like by a vacuum thin film forming technique such as vapor deposition or sputtering. A transparent electrode material 11 is adhered to one surface. Then, a photoresist 16 is formed on the surface.
Then, a pattern of the transparent electrodes 12 is formed at predetermined intervals using a photomask, and as shown in FIG. 1B, the transparent electrode material 11 is removed while leaving the pattern of the transparent electrodes 12. Thereafter, as shown in FIG.
An insulator 14 such as SiO _{2 is} adhered to the entire surface of the portion from which 1 is removed and the portion where the transparent electrode 12 remains by a vacuum thin film forming technique such as vapor deposition. Then, the transparent electrode 12 on the surface
The surface is polished by chemical mechanical polishing (CMP) so that the insulator 14 is flush with the surface. Thereafter, a light emitting layer made of an organic EL material made of a hole transporting material, an electron transporting material or another light emitting material is laminated on the entire surface by a vacuum thin film forming technique, and a back electrode is formed by a vacuum thin film forming technique. The back electrode forms a stripe pattern by mask evaporation.

Here, the deposition conditions are, for example, that the degree of vacuum is 6 ×
At 10 ⁻⁶ Torr, a film is formed at a deposition rate of 50 ° / sec in the case of an EL material. Further, the light emitting layer and the like may be formed by flash evaporation. In the flash evaporation method, an organic EL material previously mixed at a predetermined ratio is dropped to an evaporation source heated to 300 to 600 ° C., preferably 400 to 500 ° C., and the organic EL material is evaporated at a stroke. Alternatively, the organic EL material may be housed in a container, and the container may be rapidly heated and vapor-deposited at once.

According to the LE device of this embodiment, the surface on which the light emitting layer is formed is formed in a stripe shape of the transparent electrode 12 and the insulator 14 and is formed flush with the transparent electrode 12 and the back electrode. Are reliably insulated by the light emitting layer, and a short circuit does not occur during this period, thereby enabling reliable dot emission.

Next, a second embodiment of the present invention will be described with reference to FIGS. 2 (A) to 2 (D). Here, the same members as those in the above embodiment are denoted by the same reference numerals, and description thereof will be omitted. In the organic EL device of this embodiment, a transparent electrode 12 made of a transparent electrode material 11 such as ITO is formed on one side of a transparent substrate 10 made of glass, quartz, resin, or the like, and the transparent electrode 12 has a thickness of about 1 μm. Formed, for example,
It is formed with a pitch of 1.5 mm and a width of 1 mm. Along the one edge of the transparent electrode 12, a portion of the transparent electrode 12 between the transparent electrodes 12 has a stripe-shaped insulator 18 such as SiO ₂ having a thickness of 1 μm.
The thickness is about m. Further, a conductor 20 such as Al is formed between the insulator 18 and the other end of the transparent electrode 12 to a thickness of about 1 μm. Therefore, the surfaces of the transparent electrode 12, the insulator 18, and the conductor 20 are located on the same plane and are flush with each other.

As shown in FIG. 2A, the manufacturing method of the EL element of this embodiment is to form an ITO film on a surface of a transparent substrate 10 such as glass, quartz, transparent resin or the like by a vacuum thin film forming technique such as vapor deposition or sputtering. A transparent electrode material 11 is adhered to one surface. Then, a photoresist 16 is formed on the surface.
Then, a pattern of the transparent electrodes 12 is formed at predetermined intervals using a photomask, and as shown in FIG. 2B, the transparent electrode material 11 is removed while leaving the pattern of the transparent electrodes 12. Thereafter, as shown in FIG. 2C, first, the insulator 18 is attached by a vacuum thin film forming technique such as vapor deposition from a predetermined oblique direction having a component perpendicular to the stripe direction of the transparent electrode 12. . As a result, a layer of an insulator 18 such as SiO ₂ is formed in a stripe shape along the surface of the photoresist 16 and one edge of the transparent electrode 12. Next, the conductor 20 is adhered by a vacuum thin film forming technique such as vapor deposition from an oblique direction that is symmetrical with respect to the vapor deposition direction of the insulator 18 with respect to a vertical line formed on the surface of the substrate 10. Then, the transparent electrode 12 and the insulator 1 on the surface
8. The surface is polished by chemical mechanical polishing (CMP) so that the conductor 20 is flush. Thereafter, as in the first embodiment, a light emitting layer made of an organic EL material is laminated on the entire surface by a vacuum thin film forming technique, and a back electrode is formed by a vacuum thin film forming technique.

According to the LE device of this embodiment, the surface on which the light emitting layer is laminated is formed flush with the surface of the light emitting layer.
2, a pattern of the conductor 20 is formed, and the resistance of the path to the transparent electrode 12 is reduced.

Next, a third embodiment of the present invention will be described with reference to FIGS. 3 (A) to 3 (D). Here, the same members as those in the above embodiment are denoted by the same reference numerals, and description thereof will be omitted. In the organic EL device of this embodiment, a transparent electrode 12 made of a transparent electrode material 11 such as ITO is formed on one side of a transparent substrate 10 made of glass, quartz, resin, or the like, and the transparent electrode 12 has a thickness of about 1 μm. Formed, for example,
It is formed with a pitch of 1.5 mm and a width of 1 mm. The transparent electrode 12 includes a wide portion 22 and a narrow portion 24, each of which is formed in a stripe shape in parallel. Between the wide part 22 and the narrow part 24 of the transparent electrode 12, Si
An insulator 26 such as O ₂ is formed to a thickness of about 1 μm. Further, a conductor 28 made of Al or the like is formed with a thickness of about 1 μm between the transparent electrodes 12, that is, on the opposite side of the insulator 26 across the narrow width portion 24. Therefore, the surfaces of the transparent electrode 12, the insulator 26, and the conductor 28 are located on the same plane and are flush with each other.

As shown in FIG. 3A, the manufacturing method of the EL element of this embodiment is to form an ITO film on a surface of a transparent substrate 10 such as glass, quartz or transparent resin by a vacuum thin film forming technique such as vapor deposition or sputtering. A transparent electrode material 11 is adhered to one surface. Then, a photoresist 16 is formed on the surface.
Is applied, and a pattern of the transparent electrodes 12 at predetermined intervals is formed using a photomask. At this time, the transparent electrode 12 is formed so as to be separated into the wide portion 22 and the narrow portion 24. Then, as shown in FIG. 3B, the transparent electrode material 11 is removed while leaving the pattern of the transparent electrode 12. Thereafter, as shown in FIG. 3 (B), first, an insulator 26 is deposited by a mask 32 in which a relatively narrow slit 30 is formed between the large width portion 22 and the small width portion 24 of the transparent electrode 12. Formed by the vacuum thin film forming technique described above. Next, as shown in FIG. 3 (C), the conductor 28 is deposited by a mask 36 having a relatively wide slit 34 formed between the transparent electrodes 12 between the transparent electrodes 12 by vapor deposition or the like. Formed by the vacuum thin film forming technique described above. Note that the order of forming the insulator 26 and the conductor 28 may be reversed. Hereinafter, in the same manner as in the above embodiment, polishing is performed, a light emitting layer is formed, and a back electrode is formed.

According to the LE element of this embodiment, the surface on which the light emitting layer is laminated is formed to be flush with the transparent electrode 1.
2, the pattern of the conductor 20 is formed, the resistance of the path leading to the transparent electrode 12 is reduced, the insulation by the insulator 26 is ensured, and a more reliable element can be formed. . In addition, since the insulator 26 and the conductor 28 are formed by mask evaporation, a short circuit between adjacent portions does not occur.

The conductor of the organic EL device of the present invention may be formed of gold (Au) or another metal other than Al, and the thin film may be formed by sputtering other than vapor deposition or other vacuum thin film forming techniques. May be.

[0024]

According to the organic EL device and the method of manufacturing the same of the present invention, the surface on which the light emitting layer is formed is formed on a uniform plane, and a short circuit between the transparent electrode and the back electrode does not occur, thereby forming a high quality device. be able to.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a process of manufacturing an organic EL device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a manufacturing process of an organic EL device according to a second embodiment of the present invention.

FIG. 3 is a cross-sectional view illustrating a process of manufacturing an organic EL device according to a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Substrate 12 Transparent electrode 14, 18, 26 Insulator 20, 28 Conductor

Continuation of the front page (72) Inventor Tetsuya Tanbo 3158 Shimookubo, Osawanomachi, Kamishinkawa-gun, Toyama Prefecture Hokuriku Electric Industry Co., Ltd.

Claims (6)

[Claims] 1. A transparent electrode in which transparent electrode materials are formed on a transparent substrate surface at predetermined intervals, and an insulator provided between the transparent electrodes and formed substantially flush with the surface of the transparent electrode. And a back electrode formed to face the transparent electrode, and a light emitting layer of an organic EL material provided between the transparent electrode and the back electrode. 2. An insulator and a conductor are provided in a portion between the transparent electrodes, and the insulator and the conductor are formed flush with the transparent electrode. 2. The organic EL device according to 1. 3. The transparent electrode is formed in a large width portion and a narrow width portion, and is insulated by a relatively narrow insulator having a predetermined width. 2. The organic E according to claim 1, wherein a conductor is provided in a portion between the transparent electrodes on the opposite side of the body, and the surfaces of the insulator and the conductor are formed flush with the surface of the transparent electrode.
L element. 4. A transparent electrode material is adhered to one surface of the surface of a transparent substrate by a vacuum thin film forming technique such as vapor deposition, a photoresist is applied to the surface, and a transparent electrode pattern is formed at a predetermined interval using a photomask. Is formed, the transparent electrode material is removed while leaving the pattern of the transparent electrode, and thereafter, an insulator is adhered to a portion where the electrode material is removed by a vacuum thin film forming technique, and the surface thereof is covered with the transparent electrode and the transparent electrode. The surface is polished so that the insulator portion is substantially flush, a light emitting layer made of an organic EL material is laminated on the substantially flush surface by a vacuum thin film forming technique, and the back electrode is further formed by a vacuum thin film forming technique. A method for manufacturing an organic EL element to be formed. 5. A transparent electrode material is adhered to one surface of a transparent substrate by a vacuum thin film forming technique, a photoresist is applied to the surface, and a transparent electrode pattern is formed at a predetermined interval using a photomask. Removing the transparent electrode material while leaving the pattern of the transparent electrode, and then removing a portion of the electrode material at a portion having a component perpendicular to the longitudinal direction of the transparent electrode with respect to the transparent electrode. An insulator is attached by a vacuum thin film forming technique from an oblique direction, and thereafter, a conductor is attached by a vacuum thin film forming technique such as evaporation from a direction having a component substantially opposite to the attaching direction of the insulator. Thereafter, the surfaces are polished so that the transparent electrode, the insulator, and the conductor portion are substantially flush with each other, and a light emitting layer made of an organic EL material is formed on the substantially flush surface in a vacuum thin film. A method of manufacturing an organic EL element, wherein the organic EL device is laminated by a technique and the back electrode is formed by a vacuum thin film forming technique. 6. A transparent electrode material is adhered to one surface of the transparent substrate by a vacuum thin film forming technique such as vapor deposition, a photoresist is applied to the surface, and the transparent electrode material is applied to a predetermined surface using a photomask. Form a predetermined pattern so as to become a transparent electrode having a wide width portion and a narrow width portion alternately formed,
At the relatively narrow portion between the wide portion and the narrow portion of the transparent electrode, an insulator is attached by vacuum thin film formation technology by masking, and before or after this, the thick portion of the transparent electrode and A conductor is attached to the relatively wide portion between the narrow portions by masking by a vacuum thin film forming technique, and then these surfaces are substantially flush with the transparent electrode, the insulator, and the conductor portion. A method of manufacturing an organic EL device, in which a surface is polished so that a light emitting layer made of an organic EL material is laminated on the almost flush surface by a vacuum thin film forming technique, and further, a back electrode is formed by a vacuum thin film forming technique .