JP2005108678A - Organic el light emitting device and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic EL light emitting device preventing the disconnection of a positive electrode and the invasion of moisture into a seal part, and to provide a manufacturing method of the same. <P>SOLUTION: The organic EL light emitting device 100 is formed with a flattened film 106 for flattening a color filter on an element substrate 103 made of transparent glass, a positive electrode 109 arranged on the flattened film 106, an organic EL layer 102 formed between the positive electrode 109 and a negative electrode 111, and an opposing base plate 104 opposing the element substrate 103. The outer peripheral part 108 of the flattened film 106 is tapered, and the taper angle 107 of the outer peripheral part 108 of the flattened film 106 is 10 to 40°. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an organic EL (Electroluminescence) light emitting device and a method for manufacturing the same, and more particularly to an organic EL light emitting device having a color filter.

  In recent years, a color display device using an organic EL element has attracted attention because of its excellent display performance. In a configuration in which a light emitting layer is formed for each display color (red, green, blue), the light emitting layer of the organic EL layer is However, it is usually formed by R, G, and B coating methods, the device structure is complicated, and mask alignment is difficult. As described above, when the manufacturing is complicated, the cost becomes high, and it is difficult to achieve high precision and a large screen. As a configuration for solving these problems, a configuration has been proposed in which a light emitting layer is a white light emitting layer and a desired light emission color is obtained by a color filter.

FIG. 5 is a cross-sectional view of a conventional color display device. As shown in FIG. 5, in the color display device 500 having the above-described configuration, a color filter structure portion 510 including a color filter 503 and a planarizing film 504 is formed on a glass substrate 501, and the color filter structure portion 510 has an upper surface. In addition, an anode 505, an organic EL layer 506, and a cathode 507 are sequentially stacked (see Patent Document 1).
In addition, since the organic EL material has high reactivity with oxygen and moisture, a seal portion 508 is provided between the substrate 501 and the substrate 502 in order to block the organic EL layer 506 from the outside air, and the inside is sealed.

In general, the structures of the outer peripheral portions of the color filter 503 and the planarization film 504 are steep steps 509. For this reason, when the anode 505 is formed on the planarizing film 504, the thickness of the anode 505 is reduced at the step portion 509, and disconnection occurs. Further, the step 509 where the layers having different linear expansion coefficients are laminated, particularly the bent portion, is likely to generate stress, and the anode 505 is likely to float (separate) or break. Further, in such a shape, when the anode 505 is subsequently formed and patterned, erosion due to etching causes a disconnection.
On the other hand, when the planarization film 504 extends to the outside of the seal portion 508, the moisture passes through the planarization film 504 outside the seal portion 508 (moisture route 511) and enters the seal portion 508. (Moisture route 512). These moistures cause the organic EL layer 506 to deteriorate and cause dark spots.

Japanese Patent Laid-Open No. 10-116687

As described above, the structure of the conventional planarization film has a steep step at the outer periphery of the planarization film and the color filter. For this reason, the anode formed on this also has a similar step, the thickness of the anode becomes thin at the edge of the step, and stress is generated, so that the anode is easily disconnected.
On the other hand, when the planarizing film extends to the outside of the seal portion, there is a problem that moisture enters the seal portion and the organic EL light emitting layer is deteriorated.

The present invention has been made to solve such problems. The first problem to be solved by the present invention is to make the film thickness of the edge portion of the anode uniform with the structure of the planarization film. Another object of the present invention is to provide an organic EL light-emitting device that can relieve stress at this portion and prevent disconnection of the anode, and a method for manufacturing the same.
A second problem to be solved by the present invention is to provide an organic EL light-emitting device that prevents moisture from entering the seal portion.

  A first organic EL light emitting device according to the present invention includes a planarization film for planarizing a color filter, a first electrode provided on the planarization film, the first electrode, and a second electrode. An organic EL light emitting device including an organic EL layer provided between electrodes, wherein an outer peripheral portion of the planarizing film has a taper. With such a configuration, the thickness of the anode accompanying the structure of the planarizing film can be made uniform, the stress at the step portion can be relaxed, and disconnection of the anode can be prevented.

Moreover, the 1st organic electroluminescent light-emitting device concerning this invention has a taper in the outer peripheral part of the said color filter. With such a configuration, the taper of the planarizing film can be easily manufactured and the disconnection of the anode can be prevented.
In the first organic EL light emitting device according to the present invention, the planarization film has a taper angle of 10 to 40 °.

  Furthermore, in the first organic EL light emitting device according to the present invention, the end portion of the planarizing film is installed on the inner side of the outer wall surface of the sealing material for sealing. With such a configuration, moisture outside the sealing material cannot pass through the planarization film, so that moisture can be prevented from entering the sealing material and deterioration of the organic EL element can be prevented. Can be prevented.

  A first organic EL light emitting device according to the present invention includes an element substrate in which a color filter, a planarizing film, an anode, an organic EL layer, and a cathode are stacked in this order, and an opposing substrate facing the element substrate. In the light emitting device, the organic EL layer is separately disposed at a position where a pixel is formed, the color filter is disposed at a position corresponding to the arrangement of the organic EL layer, and the light emitting layer of the organic EL layer is It is a white light emitting layer, the outer peripheral part of the said planarization film | membrane has a taper, and the said taper angle is 10-40 degrees.

A second organic EL light emitting device according to the present invention includes an element substrate provided with a flattening film for flattening a color filter, and the element substrate facing the element substrate and sandwiching a sealing material for sealing. And an end portion of the flattening film is disposed on the inner side of the outer wall surface of the sealing material for sealing.
Further, the end portion of the flattening film is disposed away from the inner wall surface of the sealing material for sealing. With such a configuration, moisture outside the sealing material cannot pass through the planarization film, so that moisture can be prevented from entering the sealing material and deterioration of the organic EL element can be prevented. Can be prevented.

  A method for manufacturing an organic EL light emitting device according to the present invention is a method for manufacturing an organic EL light emitting device having a flattening film for flattening a color filter, the step of forming a color filter on a transparent substrate, and the color Forming a photosensitive resin layer on the filter; arranging a mask with a proximity gap on the surface of the photosensitive resin layer; and exposing the photosensitive resin layer by irradiating ultraviolet rays through the mask. And a step of forming a flattened film having a taper by subsequent development. With such a configuration, the thickness of the anode accompanying the structure of the planarizing film can be made uniform, the stress at the step portion can be relaxed, and disconnection of the anode can be prevented.

A method for manufacturing an organic EL light emitting device according to the present invention is a method for manufacturing an organic EL light emitting device having a color filter, the step of forming a photosensitive resin layer on a transparent substrate, and the surface of the photosensitive resin layer. And arranging a mask with a proximity gap, and exposing the photosensitive resin layer by irradiating ultraviolet rays through the mask, and thereafter developing to form a tapered color filter. With such a configuration, it becomes easy to form a taper of the flattening film on the color filter, uniform the film thickness of the anode accompanying the structure of the flattening film, relieve the stress of the stepped portion, and disconnect the anode. Can be prevented.
In the method for manufacturing an organic EL light emitting device according to the present invention, the proximity gap is 60 μm to 400 μm. By controlling the proximity gap, a color filter or a flattened film having a desired taper angle can be manufactured.

  The present invention provides an organic EL light-emitting device that prevents disconnection of the anode and prevents moisture from entering the seal portion, and a method for manufacturing the same.

  Hereinafter, embodiments to which the present invention can be applied will be described. The following description is to describe the embodiment of the present invention, and the present invention is not limited to the following embodiment. For clarity of explanation, the following description is omitted and simplified as appropriate. Further, those skilled in the art will be able to easily change, add, and convert each element of the following embodiments within the scope of the present invention. In addition, what attached | subjected the same code | symbol in each figure has shown the same element, and abbreviate | omits description suitably.

Embodiment 1 of the Invention
A first organic EL light emitting device according to the present invention will be described with reference to FIGS. FIG. 6 is a sectional view of the organic EL light emitting device according to the present invention. FIG. 1 is a cross-sectional view of an organic EL light emitting panel in the organic EL light emitting device according to the present invention. 100 is an organic EL light emitting panel, 102 is an organic EL layer, 103 is an element substrate, 104 is a counter substrate, 105 is a color filter, 106 is a planarizing film, 107 is a taper angle, 108 is an outer periphery of the planarizing film 106, 109 Is an anode, 110 is a light emitting layer, 111 is a cathode, 112 is a hole transport layer, 113 is an electron transport layer, 600 is an organic EL light emitting device, 601 is a water replenishing material, 603 is a λ / 4 plate, 604 is a polarizing plate, 605 Is an auxiliary wiring, and 606 is a driving IC.

In FIG. 6, the organic EL light emitting device 600 has an organic EL light emitting panel 100 to which a driving IC 606 is attached via an auxiliary wiring 605, and a λ / 4 plate on the surface facing the organic EL light emitting layer 102 of the element substrate 103. 603 and a polarizing plate 604 are attached.
The organic EL light emitting panel 100 has a display area composed of a plurality of pixels arranged in a matrix and a frame area that is an outer peripheral area thereof. The organic EL light emitting panel 100 includes an element substrate 103 on which an array circuit is formed and an opposite substrate 104, and the organic EL element is sealed between the two substrates. The color organic EL light emitting device has an RGB color filter 105 on an element substrate 103. Each pixel in the display area of the organic EL light emitting panel 100 performs color display of any one of RGB. Of course, a black and white display displays either white or black. In the display region on the element substrate 103, a plurality of signal lines and gate lines are arranged in a matrix. The signal line and the gate line are arranged so as to overlap each other at a substantially right angle.

Each pixel selected by the gate voltage input from the drive IC 606 applies an electric field to the organic EL light emitting layer 102 based on the display signal voltage input from the drive IC 606. A voltage input from the drive IC 606 is sent to the pixel electrode via the source / drain of the TFT, and the pixel electrode and the common electrode apply an electric field to the organic EL light emitting layer. By changing this voltage, the voltage applied to the organic EL light emitting layer can be changed, and the luminance of the light of the organic EL light emitting layer is controlled. A circuit for applying a common potential to the common electrode is configured on a control circuit board (not shown). As the organic EL light emitting panel 100, in addition to the above active matrix type, a simple matrix type having no switching element is known. The present invention is applicable to various types of organic EL light emitting panels. Alternatively, the light from the planar light source device can be applied to various display devices controlled by a panel.
The optical operation of the organic EL light emitting panel 100 will be described. White light emitted from the organic EL light emitting layer 102 is reflected by the cathode 111 made of a metal reflective electrode such as aluminum, passes through the color filter 105, and becomes R (red), G (green), and B (blue). The colors are divided. The colored light passes through the element substrate 103, the λ / 4 plate 603, and the polarizing plate 604.
Note that the λ / 4 plate 603 and the polarizing plate 604 disposed outside the element substrate 103 are for the purpose of removing the reflected light from the surface of the element substrate 103 and the reflected light from the cathode 111. Therefore, the display contrast can be remarkably improved.

  The organic EL light emitting panel of the organic EL light emitting device according to the present invention will be described with reference to FIG. In FIG. 1, an organic EL light emitting panel 100 includes a color filter 105, a planarization film 106 for planarizing unevenness on the surface of the color filter 105, an anode 109, an organic EL layer 102, and an element substrate 103 in order. The device substrate 103 including the cathode 111 and the counter substrate 104 facing the device substrate 103 are provided, and the outer peripheral portion 108 of the planarization film 106 has a taper.

  The taper angle 107 of the planarizing film 106 is 10 to 40 °, and preferably 15 to 25 °. When the taper angle 107 is less than 10 °, the surface of the outer peripheral portion 108 of the planarizing film 106 becomes rough, and even if an anode is formed thereafter, the planarized film is peeled off and disconnected. In addition, it becomes difficult to produce a taper having a desired angle. On the other hand, when the taper angle 107 exceeds 40 °, the outer peripheral portion 108 of the flattening film 106 becomes a step with a steep angle, so that the thickness of the anode 109 formed thereon becomes thin and the bent portion. The stress generated in the case becomes larger, causing disconnection.

  In FIG. 1, the outer peripheral portion of the color filter is described as a steep step, but the color filter 105 may also have a taper at the outer peripheral portion as shown in FIG. As a result, the flattening film 106 to be formed later can easily form a taper at the outer periphery.

With such a configuration, the thickness of the stepped portion of the anode 109 associated with the structure of the planarization film 106 can be made uniform, stress generated in the portion can be relaxed, and disconnection of the anode 109 can be prevented.
The organic EL layer 102 is disposed on the element substrate 103 separately at a position where a pixel is formed, and the color filter 105 is disposed at a position corresponding to the arrangement of the organic EL layer 102. Therefore, the color filter 105 is not formed on the entire surface of the element substrate 103 but is formed partially corresponding to the position of the organic EL layer 102.

In the embodiment of the present invention, the light emitting layer 110 of the organic EL layer 102 is composed of, for example, a white light emitting layer. In the present invention, red, blue and green filters are formed as color filters to obtain the three primary colors of light. Therefore, the structure of the organic EL element 102 is simple compared to a configuration that obtains the necessary three primary colors by a combination of light emission other than white light, and the red, blue, and green light-emitting layers are separately applied in terms of manufacturing. Therefore, it is not necessary to form by mask exposure.
A method for manufacturing the organic EL light emitting device according to the present invention will be described later.

Embodiment 2 of the Invention
The second organic EL light emitting device according to the present invention will be described with reference to FIGS. FIG. 4 is a sectional view of an organic EL light-emitting panel incorporated in the organic EL light-emitting device according to the present invention. 401 is a sealing material for sealing, and 701 is an organic EL light emitting region. About the structure which attached | subjected the same code | symbol as FIG. 1 and FIG. 6, the same or equivalent part is shown and description is abbreviate | omitted.

  As shown in FIG. 4, the end portion of the flattening film 106 is installed inside the outer wall surface of the sealing material 401 for sealing.

In FIG. 4A, the end portion of the planarizing film 106 is installed between the outer wall surface and the inner wall surface of the sealing material 401 for sealing.
In FIG. 4B, the end portion of the planarizing film 106 is placed in contact with the inner wall surface of the sealing material 401 for sealing.
In FIG. 4C, the end portion of the planarizing film 106 is installed away from the inner wall surface of the sealing material 401 for sealing. From the viewpoint that moisture hardly enters from the outside, it is more preferable that the end portion of the planarizing film 106 is separated from the inner wall surface of the sealing material 401 as shown in FIG.

In each of FIGS. 4A to 4C, the end portion of the planarization film 106 is shown as a steep step. On the other hand, as shown in FIG. 4D, the end portion of the flattening film 106 may be disposed apart from the inner wall surface of the sealing material 401 and may have a taper.
With such a configuration, moisture outside the sealing material cannot pass through the planarization film, so that moisture can be prevented from entering the sealing material and deterioration of the organic EL element can be prevented. Can be prevented.
As shown in FIG. 6, an anode 109 is usually formed on the planarizing film 106.
A method for manufacturing the organic EL light emitting device according to the present invention will be described later.

Embodiment 3 of the Invention
A method for manufacturing an organic EL light emitting device according to the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view of an organic EL light emitting panel of an organic EL light emitting device according to the present invention. FIG. 8 is a flowchart showing manufacturing steps of the organic EL light emitting device according to the present invention. About the structure which attached | subjected the same code | symbol as FIG.1, FIG.4 and FIG.6, the same or equivalent part is shown and description is abbreviate | omitted. The organic EL light emitting device usually includes an organic EL light emitting panel in which a plurality of organic EL layers 102 serving as pixels are arranged. As shown in FIG. 1, the organic EL light emitting panel 100 includes an element substrate 103 on which an organic EL element is formed, and a counter substrate 104 disposed to face the element substrate 103 so as to seal the organic EL layer 102. .

First, the manufacturing method of an element substrate provided with an organic EL element is demonstrated.
First, a transparent glass substrate having a thickness of, for example, 0.7 mm to 1.1 mm is used for the element substrate 103 (step S801). As the transparent glass substrate, alkali-free glass (for example, AN100 manufactured by Asahi Glass Co., Ltd.) or alkali glass (for example, AS manufactured by Asahi Glass Co., Ltd.) can be used.
A black matrix (not shown in FIG. 1) is formed and patterned on the element substrate 103 with a film thickness of about 0.1 μm, for example (step S802). The black matrix material and the formation method may be any known ones. For example, a metal chromium film can be formed by sputtering and patterned by photolithography.

  Next, the color filter 105 is arranged in a portion not covered with the black matrix (step S803). As a material of the color filter 105, the color material may be a known dye or pigment, and the colored resin may be a known material such as an epoxy resin or an acrylic resin. As a method for producing the color filter 105, a known method such as a pigment dispersion method (etching method, color resist method), a dyeing method, a dye dispersion method, a printing method, or an electrodeposition method can be used. In the embodiment of the present invention, for example, a negative acrylic photosensitive resin is used for the color filter 105, and the film thickness is about 1.2 μm.

Next, the planarizing film 106 is formed (Steps S804 and S805). The planarization film 106 is a transparent photosensitive resin layer that protects the surface of the color filter 105, planarizes the unevenness thereof, and the outer peripheral portion of the planarization film 106 is tapered.
The material of the planarizing film 106 may be a known photosensitive resin, and examples thereof include a photosensitive polyimide resin and a photosensitive acrylic resin. In the embodiment of the present invention, a negative acrylic photosensitive resin is used. Is used.

  A known method can be used as the method for forming the flattening film (step S804). If the coating solution is applied to the substrate surface by a dipping method, a spinner method, a spray method, a roll coating method, flexographic printing, or the like. Good. The thickness of the flattening film 106 is made thicker than the thickness of the color filter 105 so that the unevenness of the color filter 105 can be flattened, and the thickness is set such that the distance between the anode 109 and the color filter 105 is not too large. Is preferred. In the embodiment of the present invention, for example, a negative acrylic photosensitive resin is disposed on the color filter 105 and the black matrix so as to have a predetermined film thickness by spin coating, and becomes a planarizing film. The functional resin layer 201 was formed, and the film thickness was about 1.5 μm.

A method for forming a planarizing film (steps S804 and S805) will be described with reference to FIGS. FIG. 3 is a diagram illustrating a method for forming a photosensitive resin layer. 201 is a photosensitive resin layer, 202 is a mask, 203 to 205 are proximity gaps, 206 is ultraviolet rays, and 207 to 209 are flattening films. About the structure which attached | subjected the same code | symbol as FIG.1, FIG.4 and FIG.6, the same or equivalent part is shown and description is abbreviate | omitted.
In FIG. 3B, a photosensitive resin layer 201 is formed on the element substrate 103 which is a transparent substrate, a mask 202 is disposed with a proximity gap 204 on the surface of the photosensitive resin layer 201, and ultraviolet rays are passed through the mask. A photosensitive resin layer 208 having a taper is formed by exposing 206 to the photosensitive resin layer 201 and then developing the photosensitive resin layer 201.

Further, the photosensitive resin layer 201 in FIG. 3 corresponds to the planarizing film 106 in FIG.
In the embodiment of the present invention, the planarization film 106 is formed by irradiating with ultraviolet rays 206 as shown in FIG. 3B or FIG. 3C, and exposing the mask to cure the photosensitive resin layer 201. . When exposing the ultraviolet ray 206 to the photosensitive resin layer 201 with a mask, a specific proximity gap is provided between the mask 202 and the photosensitive resin layer 201, and the ultraviolet ray is exposed through the mask. Normally, when exposing to ultraviolet rays, as shown in FIG. 3A, the proximity gap 203 is small, and the ultraviolet rays 206 passing through the mask 202 irradiate the photosensitive resin layer 201 straight. Therefore, the outer peripheral portion of the resulting photosensitive resin layer 201 has a steep step.

  In the manufacturing method according to the present invention, it is possible to manufacture a flattening film 106 having a larger proximity gap than usual and exposing to ultraviolet rays to have a tapered outer peripheral portion 108. For example, the proximity gap 204 in FIG. 3B is set larger than the proximity gap 203 in FIG. By increasing the proximity gap, the ultraviolet ray 206 in FIG. 8B that has passed through the mask 202 is diffracted and irradiates the photosensitive resin layer 201. The ultraviolet energy passing through the mask 202 and diffracted has a lower ultraviolet energy amount than that of the ultraviolet light irradiated at the central portion, and the photosensitive resin cannot be completely cured. Therefore, the photosensitive resin layer 201 cured at the base of the diffracted ultraviolet ray is not completely cured but is cured in a tapered shape and developed.

Further, as shown in FIG. 3C, the proximity gap 205 can be set larger to form a gentler taper.
In the manufacturing method in the present invention, the proximity gap is 60 μm to 400 μm, and preferably 80 μm to 300 μm.
The exposure machine to be used is not particularly limited as long as the exposure machine can set the proximity gap.
The taper angle 107 of the planarizing film 106 formed by controlling the proximity gap is 10 to 40 °, and preferably 15 to 25 °. When the taper angle is less than 10 °, the surface of the outer peripheral portion of the planarization film 106 becomes rough, and even after the anode 109 is formed, the planarization film 106 is peeled off and disconnected. In addition, it becomes difficult to produce a taper having a desired angle. On the other hand, if the taper angle exceeds 40 °, the outer peripheral portion 108 of the flattening film 106 becomes a step having a steep angle, so that the thickness of the anode formed thereon becomes thin, and the stress in this portion becomes large. Cause disconnection.

  In FIG. 1, the end of the color filter 105 has a steep step, and the planarization film 106 has a tapered structure. The taper angle 107 is the taper angle of the planarization film 106. The shape of the outer peripheral portion of the color filter 105 may be a tapered structure in addition to such a steep step (FIG. 2). The manufacturing method of the color filter having a taper on the outer periphery is the same as the method for the planarizing film.

  The color filter 105 is disposed at a position corresponding to the organic EL layer 102 that is separately disposed. Therefore, the color filter 105 is not formed on the entire surface of the element substrate 103 but is formed partially corresponding to the position of the organic EL layer 102.

Thus, in the manufacturing method of the present invention, a desired taper angle 107 can be obtained at the outer peripheral portion of the planarization film 106 by controlling the proximity gap. As a result, the anode 109 subsequently formed on the planarizing film 106 is also uniformly deposited along the gentle slope at the outer peripheral portion 108 of the planarizing film 106, and this stress is relaxed to prevent disconnection. be able to. Further, since the anode 109 is formed with such a taper, the ITO etching solution performed thereafter is less likely to be eroded, and the occurrence of disconnection of the anode is prevented.
As a method of providing a desired taper at the outer peripheral portion 108 of the planarizing film 106, there is a method of cutting the planarizing film 106 after curing. However, it is much simpler to provide a taper at the outer peripheral portion 108 of the planarization film 106 by controlling the proximity gap as in the manufacturing method of the present invention.

  After the planarization film 106 is formed, silicon oxide for improving the adhesion of ITO, which is the electrode material of the anode 109, is formed, and then ITO is formed (step S807). ITO can be deposited with good uniformity over the entire surface of the element substrate 103 on which the planarization film 106 is formed by sputtering or vapor deposition. Here, the film is formed with a film thickness of 150 nm by a DC sputtering method. An ITO pattern is formed by photolithography and etching. This ITO pattern becomes the anode. As the resist, phenol novolac resin is used and exposure development is performed. Etching may be either wet etching or dry etching. Here, ITO was patterned using a mixed solution of hydrochloric acid and nitric acid. Monoethanolamine was used as the resist stripping material.

  A material for the auxiliary wiring 605 is formed on the ITO pattern (step S808). As the auxiliary wiring electrode material, a low-resistance metal such as Al or an Al alloy is used, and can be formed by sputtering or vapor deposition. Further, in order to improve the adhesion to the base or to prevent corrosion, a barrier layer such as TiN or Cr may be formed on the lower layer or the upper layer of the Al film to form the auxiliary wiring in a laminated structure. This barrier layer can also be formed by sputtering or vapor deposition. Here, for example, a Cr / Al / Cr laminated film or a MoNb / Al / MoNb laminated film having a total thickness of 450 nm is formed as the auxiliary wiring electrode material by DC sputtering. The auxiliary wiring electrode material is patterned by photolithography and etching to form an auxiliary wiring pattern (step S809). For the etching, an etching solution made of a mixed aqueous solution of phosphoric acid, acetic acid, nitric acid or the like can be used. It is also possible to form the anode material and the auxiliary wiring electrode material in order, and then pattern the auxiliary wiring electrode material and the anode material in order. A signal is supplied to the anode or the cathode by the auxiliary wiring pattern.

  Next, an opening insulating film is formed (step S810). As the insulating film, photosensitive polyimide is spin-coated, patterned after a photolithography process, and then cured to form an opening insulating film having a pixel opening in a pixel. At the same time, a contact hole between the cathode and the auxiliary wiring is formed. For example, the pixel opening is formed with a size of about 300 μm × 300 μm, and the contact hole between the cathode and the auxiliary wiring is formed with a size of about 200 μm × 200 μm.

  Next, a cathode barrier is formed (step S811). For the cathode partition, for example, novolac resin is used. A novolak resin is spin-coated, patterned by a photolithography process, and then photoreacted to form cathode barrier ribs. It is desirable to use a negative type photosensitive resin so that the cathode partition has an inversely tapered structure. When a negative photosensitive resin is used, when light is irradiated from above, the photoreaction becomes insufficient at deeper locations. As a result, when viewed from above, the cross-sectional area of the cured portion has a structure that is narrower on the lower side than on the upper side. This means that it has an inverted taper structure. With such a structure, the cathodes can be separated from each other because the portions that are shaded when viewed from the vapor deposition source during vapor deposition of the cathodes do not reach the vapor deposition. Further, oxygen plasma or ultraviolet light may be irradiated in order to modify the surface of the ITO layer in the opening.

Next, an organic EL element is formed on the pixel opening (step S812). For example, the organic EL layer 102 and the cathode 111 in FIG. In many cases, the organic EL layer 102 includes an interface layer, a hole transport layer, a light emitting layer, an electron injection layer, and the like. However, it may have a different layer structure.
The typical structural example of the organic EL element which can be used by this invention is shown below. But it is not limited to these, It may have a layer structure different from these.

(1) Anode / light emitting layer / cathode (2) Anode / hole injection layer / light emitting layer / cathode (3) Anode / light emitting layer / electron injection layer / cathode (4) Anode / hole injection layer / light emitting layer / electron Injection layer / cathode (5) anode / organic semiconductor layer / light emitting layer / cathode

(6) Anode / organic semiconductor layer / electron barrier layer / light emitting layer / cathode (7) anode / hole injection layer / light emitting layer / adhesion improving layer / cathode (8) anode / hole injection layer / hole transport layer / Light emitting layer / electron transport layer / electron injection layer / cathode Among these, (4) anode / hole injection layer / light emission layer / electron injection layer / cathode, (8) anode / hole injection layer / hole transport layer The configuration of / light emitting layer / electron transport layer / electron injection layer / cathode is preferable.

  The thickness of the organic EL layer 102 is usually about 100 to 300 nm. Copper phthalocyanine (CuPc) is 10 nm thick as the interface layer, and N, N′-di (naphthalen-1-yl) -N, N′-diphenyl-benzidine (α-NPD) is 60 nm thick as the hole transport layer, Alq is deposited to a thickness of 50 nm as a light emitting layer, and LiF is deposited to a thickness of 0.5 nm as an electron injection layer. In the above structure, a triphenylamine-based material such as triphenyldiamine (TPD) can be used for the hole transport layer instead of α-NPD.

  In the embodiment of the present invention, the light emitting layer 110 is composed of, for example, a white light emitting layer. In the present invention, red, blue and green filters are formed as color filters to obtain the three primary colors of light. Therefore, the structure of the organic EL element 102 is simple compared to a configuration that obtains the necessary three primary colors by a combination of light emission other than white light, and the red, blue, and green light-emitting layers are separately applied in terms of manufacturing. Therefore, it is not necessary to form by mask exposure.

  Al is often used for the cathode 111, but alkali metals such as Li, Ag, Ca, Mg, Y, In, and alloys containing them can also be used. The thickness of the cathode 111 is usually about 50 to 300 nm, and here it is assumed that the thickness is 200 nm. In addition, the cathode 111 can be formed by physical vapor deposition (PVD) such as sputtering or ion plating. Thereby, an organic EL element is formed. Through these steps, an element substrate on which a plurality of organic EL elements are formed is manufactured. Usually, a plurality of organic EL display panels having a plurality of organic EL elements are formed on one substrate. Then, by cutting and separating each organic EL display panel, a plurality of organic EL display panels can be obtained from one mother glass. The manufacturing process of the organic EL element substrate described above is an example of a manufacturing process of an element substrate used in a typical organic EL display device, and is not limited to the manufacturing process described above.

Next, the manufacturing process of the counter substrate for sealing the organic EL element will be described with reference to FIGS. The same reference numerals as those in FIGS. 1, 3, 4, and 6 denote the same or corresponding parts, and the description thereof is omitted.
Since the organic EL element is deteriorated by moisture in the air, the counter substrate 104 is used for sealing in a nitrogen atmosphere. A glass substrate having a thickness of 0.7 mm to 1.1 mm is used as the counter substrate 104 (step S821), and the same substrate as the element substrate 103 can be used. Then, the counter substrate 104 is processed to provide a water catching material storage unit for placing the water catching material 601 for capturing moisture (step S822) (not shown in FIG. 6). The water catching material storage unit is formed, for example, by digging a part of the counter substrate 104 by etching or sandblasting. The water catching material 601 is disposed in the water catching material storage unit (step S823). For the water catching material 601, calcium oxide powder or the like is used.

Subsequently, application | coating of the sealing material for sealing is demonstrated using FIG.7 and FIG.8. FIG. 7 is a plan view of the organic EL light emitting device according to the present invention. Reference numeral 701 denotes an organic EL display area, and reference numeral 702 denotes an organic EL light emitting panel. The same reference numerals as those in FIGS. 1, 3, 4, and 6 denote the same or corresponding parts, and the description thereof will be omitted.
In FIG. 6, a water replenishing material 601 is provided inside the sealing material 401 for sealing, but a getter agent for absorbing a gas such as oxygen may be used in addition to this.

  First, the sealing material 401 for sealing is apply | coated to the surface in which the water catching material accommodating part of the opposing board | substrate 104 was provided using dispenser (step S824). The sealing material 401 for sealing is provided so as to surround the organic EL display region 701. As the sealing material 401 for sealing, a photosensitive epoxy resin is desirable. For example, a photocationic polymerization type epoxy resin can be used and functions as an adhesive for bonding the element substrate 103 and the counter substrate 104 together.

  The positional relationship between the sealing sealant 401 and the end portion of the planarizing film 106 is important in blocking moisture outside the sealing sealant 401. That is, as shown in each drawing of FIG. 4, in the organic EL light emitting device according to the present invention, the planarization film 106 is arranged so that the end portion is inside the outer wall surface of the sealing material 401 for sealing. ing.

  For example, in FIG. 4A, the end portion of the planarizing film 106 is disposed so as to be inside the outer wall surface and the inner wall surface of the sealing material 401 for sealing. In FIG. 4B, the end portion of the planarizing film 106 is disposed so as to contact the inner wall surface of the sealing material 401 for sealing. In FIG. 4C, the end portion of the planarizing film 106 is disposed away from the inner wall surface of the sealing material 401 for sealing. As described above, since the planarization film 106 does not extend to the outside of the sealing material 401, moisture outside the sealing material 401 is sealed via the sealing material 401. 401 cannot enter the inside. Therefore, deterioration of the organic EL layer 102 due to moisture can be prevented.

In each of FIGS. 4A to 4C, the end portion of the planarization film 106 is shown as a steep step. Further, as shown in FIG. 4D, the end portion of the planarizing film 106 may be disposed apart from the inner wall surface of the sealing material 401 for sealing and may have a tapered shape.
A sealing substrate is manufactured by the above manufacturing process. The above manufacturing process is a typical example, and the present invention is not limited to this.

  Next, the element substrate and the counter substrate are bonded together to seal the organic EL element (step S813). Subsequent steps will be described with reference to FIGS. The same reference numerals as those in FIGS. 1, 3, 4, and 6 denote the same or corresponding parts, and the description thereof is omitted.

  The element substrate 103 is provided with an organic EL display region 701 including a plurality of organic EL elements formed in the above steps S801 to S812 and an auxiliary wiring 605 for supplying a signal to each element. As shown in FIG. 7, the element substrate 103 is provided with six organic EL display regions 701, and an organic EL light emitting panel is formed by cutting and separating the substrate. On the counter substrate 104 slightly smaller than the element substrate 103, a water catching material storage portion is formed for each organic EL display region 701, and a water catching material 601 is arranged. The counter substrate 104 is provided with a sealing material 401 for sealing that surrounds each organic EL display region 701.

  The element substrate 103 and the counter substrate 104 are aligned so as to face each other, both substrates are pressurized, and each sealing material is irradiated with UV light. As a result, as shown in FIG. 6, the two substrates are bonded. Each organic EL display region 701 provided on the element substrate 103 is surrounded by a sealing material 401 for sealing as shown in FIG. A water catching material 601 is disposed in a space surrounded by both substrates and the sealing material 401 for sealing, and prevents deterioration of the organic EL element due to moisture remaining or entering the sealed space. The organic EL element is sealed with a pair of substrates including the element substrate 103 and the counter substrate 104. Since the auxiliary wiring 605 is connected to an external drive circuit, part of the sealing material 401 for sealing may be bonded across the auxiliary wiring 605.

  After the element substrate 103 and the counter substrate 104 are bonded together to form a pair of substrates, a drive circuit and the like are mounted (step S814). An auxiliary wiring 605 is disposed on the element substrate 103 outside the region surrounded by the sealing material 401 for sealing. A terminal portion is formed at an outer end portion of the auxiliary wiring 605, and an anisotropic conductive film (ACF) is attached to the terminal portion to connect the driving IC 606. Specifically, ACF is temporarily crimped to the terminal portion. ACF uses Hitachi Chemical Anisolm 7106U. The temporary pressure bonding temperature is 80 ° C., the pressure bonding pressure is 1.0 MPa, and the pressure bonding time is 5 seconds. Next, the driving IC is finally bonded to the terminal portion. The main press bonding temperature was 170 ° C. As a result, the driving IC is mounted. Further, a flexible substrate for supplying a signal from the outside to the driving IC 606 is connected.

Thereafter, a λ / 4 plate 603 and a polarizing plate 604 are attached to the surface of the element substrate 103 facing the counter substrate 104, and this organic EL display panel is attached to the housing, thereby completing the organic EL display device (step). S815). Thus, an organic EL display device can be provided.
Through these steps, a substrate element on which a plurality of organic EL layers 102 are formed is manufactured. Usually, a plurality of organic EL display panels having a plurality of organic EL elements are formed on one element substrate. The manufacturing process of the organic EL element substrate described above is an example of a manufacturing process of an element substrate used in a typical organic EL display device, and is not limited to the above manufacturing process.

The organic EL light emitting device of the present invention can also be used for an organic EL display device or an organic EL light source device using an organic EL element. The organic EL light emitting device includes devices utilizing light emission of an organic EL element such as an organic EL display device and an organic EL light source device.
Hereinafter, the present invention will be described more specifically with reference to examples.

(Creation of organic EL light emitting device 1)
First, a negative type acrylic photosensitive resin (RE0410 manufactured by Mitsubishi Chemical Corporation) was used on a transparent glass substrate to form a color filter having a film thickness of about 1.2 μm. Thereafter, a transparent flattening film was formed on the color filter. As a material for the flattening film, a negative acrylic photosensitive resin (V2301PR manufactured by Nippon Steel Chemical Co., Ltd.) was used and formed with a film thickness of about 1.5 μm. Thereafter, using a mask having an opening corresponding to the organic EL display area, a high pressure mercury lamp is used as a light source, and an ultraviolet ray is irradiated under the conditions of an exposure amount of 400 mJ and a proximity gap of 150 μm. The planarizing film was cured. After the flattening film was cured, it was developed with a potassium carbonate / potassium bicarbonate mixed developer to obtain a flattening film having an outer peripheral taper angle of 20 °.

  Then, 5 mm of silicon oxide was formed, and then ITO was formed as an anode with a resistance value of 10Ω / □ and a film thickness of about 150 nm. An organic EL layer was formed on the ITO. Copper phthalocyanine (CuPc) is 10 nm thick as the hole injection layer, and N, N′-di (naphthalen-1-yl) -N, N′-diphenyl-benzidine (α-NPD) is thick as the hole transport layer. 60 nm, Alq as a light emitting layer was deposited with a thickness of 30 nm, and LiF was deposited as an electron injection layer with a thickness of 30 nm. The light emitting layer was a white light emitting layer. Al was used for the cathode, and its thickness was about 200 nm. Thus, the organic EL light emitting device 1 having a taper angle of 20 ° at the outer peripheral portion of the planarizing film was formed.

(Creation of organic EL light emitting devices 2 to 10)
In Example 1, organic EL light emitting devices 2 to 10 were produced in the same manner as in Example 1 except that the value of the proximity gap was changed as shown in Table 1.

(Evaluation of disconnection rate of organic EL light emitting device)
The organic EL light-emitting device 1 having a taper angle of 20 ° at the outer peripheral portion of the planarizing film prepared in Example 1 was driven, and the disconnection of the anode wiring was confirmed depending on whether light was emitted. For each taper angle, 100 organic EL light emitting devices were used.
In the same manner, the organic EL light emitting devices 2 to 10 were evaluated.
The results are shown in Table 1.

It is sectional drawing which shows the structure of the organic electroluminescent light emission panel concerning this invention. It is sectional drawing which shows the structure of the organic electroluminescent light emission panel concerning this invention. It is sectional drawing which shows the exposure state of the photosensitive resin layer in the manufacturing method of the organic electroluminescent light emitting device concerning this invention. It is sectional drawing which shows the position of the sealing material for sealing, and the planarization film | membrane of the organic electroluminescent light emitting device concerning this invention. It is sectional drawing which shows the structure of the conventional organic electroluminescent light emission panel. It is sectional drawing which shows the structure of the organic electroluminescent light-emitting device concerning this invention. It is a top view which shows the structure of the organic electroluminescent light-emitting device concerning this invention. It is a flowchart which shows the manufacturing process of the organic electroluminescent light emitting device concerning this invention.

Explanation of symbols

100: Organic EL light emitting panel
102: Organic EL layer 103: Element substrate 104: Counter substrate 105: Color filter 106: Flattened film 107: Tapered angle 108: Peripheral part 109 of the flattened film 109: Anode 110: Light emitting layer 111: Cathode 112: Hole transport layer 113: Electron transport layer 201: Photosensitive resin layer 202: Masks 203, 204, 205: Proximity gap 206: Ultraviolet rays 207, 208, 209: Planarization film 401: Sealing sealing material 501: Organic EL light emitting panel 501 502: Substrate 503: Color filter 504: Flattened film 505: Anode 506: Organic EL layer 507: Cathode 508: Seal part 509: Anode end part 510: Color filter structure part 511, 512: Water intrusion 600: Organic EL light emission Device 601: Water replenishment material 603: λ / 4 plate 604: Polarizing plate 605: Auxiliary wiring 60 6: Drive IC 701: Organic EL display region 702: Organic EL light emitting panel

Claims (10)

A flattening film for flattening the color filter, a first electrode provided on the flattening film, and an organic EL layer provided between the first electrode and the second electrode are provided. An organic EL light emitting device,
An organic EL light emitting device having an outer peripheral portion of the planarizing film having a taper.   The organic EL light-emitting device according to claim 1, wherein an outer peripheral portion of the color filter has a taper.   The organic EL light-emitting device according to claim 1, wherein a taper angle of the planarizing film is 10 to 40 °.   The organic EL light-emitting device according to claim 1, wherein an end portion of the planarizing film is installed on an inner side than an outer wall surface of the sealing material for sealing. An element substrate in which a color filter, a planarizing film, an anode, an organic EL layer and a cathode are laminated in this order;
An organic EL light emitting device having a counter substrate facing the element substrate,
The organic EL layer is separately disposed at a position where a pixel is formed,
The color filter is arranged at a position corresponding to the arrangement of the organic EL layer,
The light emitting layer of the organic EL layer is a white light emitting layer,
An organic EL light emitting device in which an outer peripheral portion of the planarizing film has a taper, and the taper angle is 10 to 40 °. An element substrate having a flattening film for flattening the color filter;
Opposing the element substrate, and having a counter substrate fixed to the element substrate with a sealing material interposed therebetween,
An organic EL light-emitting device in which an end portion of the flattening film is installed inside an outer wall surface of the sealing material for sealing.   The organic EL light-emitting device according to claim 6, wherein an end portion of the planarizing film is disposed apart from an inner wall surface of the sealing material for sealing. A method for manufacturing an organic EL light-emitting device having a flattening film for flattening a color filter,
Forming a color filter on a transparent substrate;
Forming a photosensitive resin layer on the color filter;
Placing a mask with a proximity gap on the surface of the photosensitive resin layer;
Forming a planarized film having a taper by exposing the photosensitive resin layer by irradiating ultraviolet rays through a mask and then developing the organic resin light emitting device. A method of manufacturing an organic EL light emitting device having a color filter,
Forming a photosensitive resin layer on a transparent substrate;
Placing a mask with a proximity gap on the surface of the photosensitive resin layer;
Forming a color filter having a taper by exposing the photosensitive resin layer by irradiating ultraviolet rays through a mask and then developing the organic resin light-emitting device.   The method for manufacturing an organic EL light-emitting device according to claim 8 or 9, wherein the proximity gap is 60 μm to 400 μm.

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