WO2017072920A1

WO2017072920A1 - Organic el display device

Info

Publication number: WO2017072920A1
Application number: PCT/JP2015/080604
Authority: WO
Inventors: 小玉　光文; 恵紺野; 洋平藤村; 朋久高山; 圭介渡辺
Original assignee: 双葉電子工業株式会社; 双葉モバイルディスプレイ株式会社
Priority date: 2015-10-29
Filing date: 2015-10-29
Publication date: 2017-05-04

Abstract

The present disclosure relates to an organic EL display device wherein deterioration of the service life is suppressed. This organic EL display device is provided with: a first substrate; a first light emitting element and a second light emitting element, which are provided on the first substrate, and include organic EL layers, respectively; an element isolating section, which is provided on the first substrate, and separates the first light emitting element and the second light emitting element from each other; a second substrate that is provided on the first light emitting element, the second light emitting element, and the element isolating section; and a filling material that is provided such that a gap between the first substrate and the second substrate is filled with the filling material. The first substrate, first light emitting element, second light emitting element, element isolating section, second substrate, and filling material have light transmitting characteristics, and the filling material contains a desiccant having light transmitting characteristics, and covers an exposed region of the element isolating section.

Description

Organic EL display device

The present invention relates to an organic EL display device.

In recent years, a self-luminous display device using an organic EL layer (EL: Electro-Luminescence) as a light emitting layer has been used as a display device. For example, Patent Document 1 described below describes a panel of a passive matrix organic EL display device having an image display array composed of a plurality of light emitting units. Such a panel is provided with a plurality of strip-shaped partition walls arranged side by side.

JP-A-8-315981

In Patent Document 1, a plurality of light emitting portions are separated from each other by separating a conductive layer provided on the light emitting layer using a partition wall. When the conductive layer is separated using the partition wall in this way, a part of the partition wall is exposed without being covered with the conductive layer. There is a risk that moisture in the air may enter the panel from the exposed portion of the partition wall. When moisture enters the organic EL layer, the lifetime of the organic EL layer is reduced, and the reliability of the organic EL display device is reduced.

In recent years, the organic EL display device has been made a see-through type to improve the design. In such a see-through organic EL display device, a light-impermeable desiccant cannot be disposed on the light emitting layer. Therefore, in the see-through type organic EL display device having the structure of Patent Document 1, the lifetime of the organic EL layer is significantly reduced.

An object of one aspect of the present invention is to provide an organic EL display device capable of suppressing a reduction in lifetime.

An organic EL display device according to one embodiment of the present invention is provided over a first substrate, a first substrate, a first light-emitting element and a second light-emitting element each including an organic EL layer, and the first substrate. A first light emitting element, a second light emitting element, a second substrate provided on the second light emitting element, and the element separating section; a first substrate; The first substrate, the first light-emitting element, the second light-emitting element, the element separating portion, the second substrate, and the filler have a light-transmitting property. The filler includes a light-transmitting desiccant and covers the exposed region of the element isolation portion.

The element isolation portion includes a strip-shaped first portion provided on the first substrate and a strip-shaped second portion provided on the first portion. In the width direction of the element isolation portion, the second portion Both sides of the part may protrude from the first part.

Further, the second portion may have a taper shape in the width direction cross section.

Further, the second portion may have a width direction cross-section inversely tapered shape.

In addition, the organic EL display device described in the above paragraph is further provided with a frame-shaped adhesive portion that is provided along the edge of the first substrate and joins the first substrate and the second substrate. The region surrounded by the part may be filled.

Further, the first substrate and the second substrate may have flexibility.

According to one embodiment of the present invention, it is possible to provide an organic EL display device that can suppress a reduction in lifetime.

FIG. 1 is a schematic perspective view showing the organic EL display device according to the first embodiment. FIG. 2 is a sectional view taken along line AA in FIG. FIG. 3 is a sectional view taken along line BB in FIG. FIG. 4 is a partial cross-sectional view of the organic EL display device according to the second embodiment. FIG. 5A is a partial cross-sectional view of an organic EL display device according to a first modification of the second embodiment. FIG. 5B is a partial cross-sectional view of an organic EL display device according to a second modification of the second embodiment.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, the same reference numerals are used for the same elements or elements having the same functions, and redundant description is omitted.

(First embodiment)
FIG. 1 is a schematic perspective view showing the organic EL display device according to the first embodiment. An organic EL display device 1 shown in FIG. 1 is a self-luminous passive matrix display using an organic EL. The organic EL display device 1 includes an element substrate 2 (first substrate), light emitting elements 3A to 3F and

element separation portions

4A and 4B provided on the element substrate 2, an element substrate 2, light emitting elements 3A to 3F, and elements A sealing substrate 5 (second substrate) provided on the

separation portions

4A and 4B, an external connection circuit 6, and an adhesive portion 7 for joining the element substrate 2 and the sealing substrate 5 are provided. Although omitted in FIG. 1, the organic EL display device 1 includes a plurality of light-emitting elements (not shown) other than the light-emitting elements 3A to 3F and a plurality of element separation parts (not shown) other than the

element separation parts

4A and 4B.

The element substrate 2 has insulation and light transmission and has a substantially rectangular main surface 2 a facing the sealing substrate 5. The light transmissive property means a function of transmitting at least part of light. For example, the element substrate 2 having light transmissivity may have a function of transmitting incident light and may absorb or reflect a part of the light. For example, a glass substrate or a plastic substrate is used as the element substrate 2. When the organic EL display device 1 has flexibility, for example, a PET film (polyethylene terephthalate film) or a polyimide film is used as the element substrate 2. On the main surface 2a of the element substrate 2, in addition to the light emitting element and the element separating portion, a driving circuit for driving the light emitting element, wiring for connecting the driving circuit and the light emitting element, an external connection terminal, and the like are provided. .

The light emitting elements 3A to 3F are self-light emitting elements arranged in a matrix on the main surface 2a, and correspond to the pixels of the organic EL display device 1. The light emitting elements 3A to 3F are independently controlled to a light emitting state or a non-light emitting state. For example, in the organic EL display device 1, only the light emitting element 3A can be in a light emitting state, and the light emitting elements 3B to 3F can be in a non-light emitting state. The light emitting elements 3A to 3F have the same structure.

The

element separating portions

4A and 4B are members that separate adjacent light emitting elements, and extend so as to form a belt shape in a plan view. As shown in FIG. 1, when the light emitting elements 3A to 3C are arranged in order along the extending direction of one side of the main surface 2a, the element separating portion 4A is located between the adjacent

light emitting elements

3A and 3B. The

light emitting elements

3A and 3B are separated by extending in a direction orthogonal to the extending direction. Similarly, the element separation part 4B extends in a direction orthogonal to the extending direction between the adjacent

light emitting elements

3B and 3C, and separates the

light emitting elements

3B and 3C. Detailed configurations of the light emitting element and the element separating portion will be described later. Note that the direction orthogonal to the extending direction is not limited to a direction intersecting at right angles to the extending direction, and may be a direction intersecting substantially at right angles.

The sealing substrate 5 has insulation and light transmission, and has a substantially rectangular main surface 5 a facing the element substrate 2. The sealing substrate 5 is a substrate that covers the region where the light emitting element is provided by bonding to the element substrate 2 through the bonding portion 7. For example, a glass substrate or a plastic substrate is used as the sealing substrate 5. When the organic EL display device 1 has flexibility, for example, a PET film (polyethylene terephthalate film) or a polyimide film is used as the sealing substrate 5.

The external connection circuit 6 is a circuit connected to a drive circuit or the like provided on the main surface 2 a of the element substrate 2. The organic EL display device 1 can be connected to an external device, a power source, and the like via an external connection circuit 6 connected to an external connection terminal provided on the element substrate 2. As the external connection circuit 6, for example, an FPC (Flexible Printed Circuit) is used.

The bonding portion 7 is a member that joins the element substrate 2 and the sealing substrate 5 as described above, and is a frame-like member provided along the edge of the element substrate 2. The bonding portion 7 is provided so as to surround the light emitting element and the element separation portion provided on the element substrate 2. FIG. 2 is a sectional view taken along line AA in FIG. As shown in FIG. 2, the bonding portion 7 accurately bonds the second insulating film 13 on the first insulating film 11 provided on the main surface 2 a of the element substrate 2 and the sealing substrate 5. Yes. The bonding portion 7 includes, for example, an ultraviolet curable epoxy resin. The edge of the element substrate 2 may include a region around the edge of the element substrate 2.

FIG. 3 is a sectional view taken along line BB in FIG. As shown in FIG. 3, on the main surface 2a of the element substrate 2, the first insulating film 11, the first electrode 12, the second insulating film 13, the organic EL layers 14A and 14B, and the

second electrode

15A and 15B, the element isolation | separation part 4A, the filler 16, and the sealing substrate 5 are provided. On the main surface 2a, the light emitting element 3A (first light emitting element) is formed by the first electrode 12, the organic EL layer 14A, and the second electrode 15A. Further, the light emitting element 3B (second light emitting element) is formed by the first electrode 12, the organic EL layer 14B, and the second electrode 15B.

The first insulating film 11 is a light transmissive film provided so as to cover the main surface 2 a of the element substrate 2. As the first insulating film 11, for example, a silicon oxide film, a silicon nitride film, a silicon oxynitride film, or an aluminum oxide film is used. The first insulating film 11 is formed by, for example, a CVD method (chemical vapor deposition method).

The first electrode 12 is an electrode that functions as an anode of the

light emitting elements

3A and 3B, and is provided on the first insulating film 11. The first electrode 12 is composed of a transparent conductive layer patterned in a stripe shape. The first electrode 12 extends in a direction orthogonal to the extending direction of the element isolation portion 4A, in other words, in a direction from the light emitting element 3A toward the light emitting element 3B. As a material for the transparent conductive layer, for example, ITO (indium tin oxide) is used. The transparent conductive layer may have a single layer structure or a multilayer structure. The transparent conductive layer is formed by, for example, vapor deposition using an electron beam or the like, or PVD method (physical vapor deposition method) such as sputtering. The first electrode 12 is formed by patterning the formed transparent conductive layer using, for example, a resist mask. Note that the transparent conductive layer may be a conductive layer having optical transparency, and may not be a completely transparent conductive layer.

The second insulating film 13 is a light transmissive film provided on the first insulating film 11 and the first electrode 12. As the second insulating film 13, for example, an inorganic film such as a silicon oxide film, a silicon nitride film, a silicon oxynitride film, or an aluminum oxide film, or an organic film such as a novolac resin, an acrylic resin, or a polyimide is used. The thickness of the second insulating film 13 is about 1 μm, for example. When the second insulating film 13 is an inorganic film, the second insulating film 13 is formed by, for example, a CVD method. When the second insulating film 13 is an organic film, the second insulating film 13 is formed by, for example, spin coating. The second insulating film 13 is provided with

openings

13a and 13b. A portion of the first electrode 12 is exposed from the second insulating film 13 through the

openings

13a and 13b. The opening 13a is formed to provide the light emitting element 3A, and the opening 13b is formed to provide the light emitting element 3B. The

openings

13a and 13b are provided by patterning using a resist mask, for example.

The organic EL layers 14A and 14B are layers including at least an organic compound (light emitting material) that emits light when electrons and holes are injected. The organic EL layer 14 A is a light transmission layer that is in contact with the first electrode 12 in the opening 13 a and is provided on the second insulating film 13. The organic EL layer 14B is a light transmission layer provided on the second insulating film 13 while being in contact with the first electrode 12 in the opening 13b. The thickness of the organic EL layers 14A and 14B is, for example, not less than 100 nm and not more than 500 nm. The organic EL layers 14A and 14B are formed, for example, by a dry method such as a vacuum evaporation method or a wet method such as an inkjet. In the first embodiment, a dry method is applied to form (patterned) organic EL layers 14A and 14B separated (patterned) by the element isolation unit 4A (details will be described later).

The light emitting material contained in the organic EL layers 14A and 14B may be a low molecular compound or a high molecular compound. The light emitting material may be a fluorescent material or a phosphorescent material. The organic EL layers 14A and 14B may include an electron injection layer, an electron transport layer, a hole injection layer, a hole transport layer, and the like in addition to the light emitting layer containing the light emitting material. In this case, for example, the organic EL layers 14 A and 14 B are formed by sequentially stacking a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer on the first electrode 12. The light generated by the organic EL layers 14A and 14B may be monochromatic light such as red light or blue light, or may be white light. When the organic EL layers 14A and 14B exhibit white light, each of the organic EL layers 14A and 14B may include a plurality of light emitting layers that generate different lights.

The

second electrodes

15A and 15B are electrodes that function as cathodes of the

light emitting elements

3A and 3B, respectively. The second electrode 15A is provided on and in contact with the organic EL layer 14A. The second electrode 15B is provided in contact with the organic EL layer 14B. Each of the

second electrodes

15A and 15B is composed of a patterned transparent conductive layer. As a material for the transparent conductive layer, for example, IZO (indium zinc oxide), aluminum, silver, and magnesium are used. The transparent conductive layer may have a single layer structure or a multilayer structure. When the transparent conductive layer includes any one of an aluminum film, a silver film, and a magnesium film, each of the aluminum film, the silver film, and the magnesium film has a thickness of about 1 nm or less. A transparent conductive layer is formed by PVD methods, such as vapor deposition using an electron beam etc., or sputtering, for example. In the first embodiment,

second electrodes

15A and 15B separated (patterned) by the element separation unit 4A are formed (details will be described later).

The element separation portion 4A provided between the

light emitting elements

3A and 3B is provided on the second insulating film 13 that is not covered with the organic EL layers 14A and 14B and the

second electrodes

15A and 15B. The element isolation portion 4A is in contact with the second insulating film 13 and extends substantially parallel to the main surface 2a of the element substrate 2, and the top surface 4b that faces the bottom surface 4a and extends substantially parallel to the bottom surface 4a. And side surfaces 4c and 4d connecting the bottom surface 4a and the top surface 4b. In a direction perpendicular to the direction in which the element isolation portion 4A extends in a strip shape (the width direction of the element isolation portion 4A), the length of the top surface 4b is larger than the length of the bottom surface 4a, and both sides of the top surface 4b are on the bottom surface 4a. Protruding from. The side surface 4c is an inclined surface from one end of the bottom surface 4a on the light emitting element 3A side to one end of the top surface 4b on the light emitting element 3A side, and the side surface 4d is the top surface from the other end of the bottom surface 4a on the light emitting element 3B side. 4b is an inclined surface toward the other end of the light emitting element 3B side. Therefore, the element isolation portion 4A has an inversely tapered shape in the cross section in the width direction. The height of the element isolation portion 4A is larger than the total thickness of the organic EL layer 14A and the second electrode 15A (or the total thickness of the organic EL layer 14B and the second electrode 15B), for example, 2 μm or more and 10 μm or less. It is. The element isolation portion 4A is formed of an organic resin having light transmissivity such as a novolac resin. The plurality of element isolation parts including the element isolation part 4B have substantially the same shape as the element isolation part 4A.

The element isolation part 4A is provided on the second insulating film 13 before the formation of the organic EL layers 14A and 14B and the

second electrodes

15A and 15B. Therefore, on the top surface 4b of the element isolation portion 4A, an organic layer 17 made of the same material as the organic EL layers 14A and 14B, and a conductive layer 18 made of the same material as the

second electrodes

15A and 15B, Is provided. By providing the organic layer 17 on the element separation portion 4A, the organic EL layers 14A and 14B are favorably separated. Similarly, by providing the conductive layer 18 on the element isolation portion 4A, the

second electrodes

15A and 15B are well separated.

The bottom surface 4 a is in contact with the second insulating film 13. Further, as described above, the top surface 4 b is covered with the organic layer 17. For this reason, the bottom surface 4a and the top surface 4b in the element isolation portion 4A are not exposed. On the other hand, the side surfaces 4c and 4d of the element isolation portion 4A are exposed regions that are not covered by the organic layer 17 and the conductive layer 18 or the like. Although not shown, the side surface orthogonal to the extending direction of the element isolation portion 4A may be an exposed region or not an exposed region.

Here, an example of a method for forming the element isolation portion according to the first embodiment will be described. First, a resin layer having a thickness of about 3 μm is formed on the second insulating film 13 by applying a resin on the second insulating film 13 by spin coating and then performing a heat treatment at 100 ° C. to 150 ° C. In the first embodiment, a negative resist is used as the resin. Next, a part of the resin layer is exposed using a photomask in which a stripe-shaped opening is formed. Next, heat treatment is performed at 100 ° C. to 150 ° C., and the resin layer is developed using tetramethylammonium hydroxide (TMAH). The development of the resin layer means removing an unexposed area in the resin layer. Further, by performing a heat treatment at 100 ° C. to 150 ° C., a plurality of band-shaped element isolation portions extending in a predetermined direction are formed.

The filler 16 is a member provided so as to fill a gap between the element substrate 2 and the sealing substrate 5. The filler 16 includes the second insulating film 13 on the element substrate 2, the organic EL layers 14A and 14B, the

second electrodes

15A and 15B, the side surfaces 4c and 4d that are exposed regions of the element isolation portion 4A, the organic layer 17, and the conductive layer. Covers layer 18. The filler 16 is filled in a region surrounded by the adhesive portion 7 between the element substrate 2 and the sealing substrate 5 and is in contact with the sealing substrate 5 without a gap. The filler 16 is formed of an organic resin having light transmissivity such as an epoxy resin. The filler 16 is provided on the element substrate 2 by a coating method such as an inkjet method or a dispensing method. The filler 16 may be in a cured state or in an uncured state.

The filler 16 includes a desiccant having light permeability. A linear or cyclic organometallic compound is used as the filler containing a desiccant having light permeability. This organometallic compound includes, for example, any of aluminum, lanthanum, yttrium, gallium, silicon, or germanium. In this embodiment, for example, OleDry (trademark) manufactured by Futaba Electronics Co., Ltd. is used. The content of the desiccant in the filler 16 may be 50% by weight or more and 95% by weight or less. In this case, the filler 16 can suitably absorb moisture remaining in the gap between the element substrate 2 and the sealing substrate 5 and moisture entering from the partition wall. Further, the filler 16 can satisfactorily fill the gap.

According to the organic EL display device 1 according to the first embodiment described above, the filler 16 covers the side surfaces 4c and 4d, which are exposed regions of the element separation portion 4A that separates the light emitting element 3A and the light emitting element 3B. At the same time, it is provided so as to fill a gap between the element substrate 2 and the sealing substrate 5. For this reason, the air between the element substrate 2 and the sealing substrate 5 is pushed out by the filler 16, and the exposed region of the element separation portion 4A is covered with the filler 16 so as not to contact the air. Thereby, it can suppress that the water | moisture content in air permeates into the organic EL layer 14A of the light emitting element 3A and the organic EL layer 14B of the light emitting element 3B adjacent to the element separating part 4A through the exposed region of the element separating part 4A. . Here, since the filler 16 contains a desiccant, moisture around the light emitting element and the element separation portion in the organic EL display device 1 is absorbed by the desiccant in the filler 16. In addition, since the desiccant can come into contact with the exposed region of the element isolation portion, it is very difficult for moisture in the air to enter the organic EL layers 14A and 14B through the exposed region.

Since the filler 16 also covers the second insulating film 13 exposed from the organic EL layers 14A and 14B and the

second electrodes

15A and 15B, the moisture in the air is organic through the second insulating film 13. Infiltration into the EL layers 14A and 14B can also be suppressed. Further, since the filler 16 also covers the organic EL layers 14A and 14B, it is possible to suppress moisture in the air from directly entering the organic EL layers 14A and 14B. In addition, gas can be prevented from being released from the exposed region of the element isolation portion 4A by the filler 16. Furthermore, since the filler 16 according to the first embodiment covers all the light emitting elements and the element separating portion in the organic EL display device 1, the filling material 16 is provided for the organic EL layer included in the light emitting elements other than the light emitting elements 3 A and 3 B. Infiltration of moisture can also be suppressed.

Moreover, according to the organic EL display device 1 according to the first embodiment, since the desiccant is contained in the filler 16, it is not necessary to provide the desiccant outside the region where the light emitting element is provided in the element substrate 2. In this case, the area surrounded by the bonding portion 7 can be expanded.

In addition, according to the organic EL display device 1 according to the first embodiment, the element substrate 2, the light emitting elements 3A to 3F, the

element separation portions

4A and 4B, the sealing substrate 5, and the filler 16 have light transmittance. The desiccant contained in the filler 16 is light transmissive. Thereby, the organic EL display device 1 can emit light to both the element substrate 2 side and the sealing substrate 5 side.

In summary, according to the first embodiment, in addition to being able to suppress a decrease in the lifetime of the organic EL display device 1, a see-through type organic EL display device capable of double-sided light emission and having a narrow frame. Can provide.

The organic EL display device 1 according to the first embodiment includes a frame-shaped adhesive portion 7 that is provided along the edge of the element substrate 2 and joins the element substrate 2 and the sealing substrate 5. May be filled in a region surrounded by the bonding portion 7. In this case, since the filler 16 is suppressed from leaking from the edges of the element substrate 2 and the sealing substrate 5, the yield of the organic EL display device 1 is improved. In addition, since the region where the filler 16 is formed is limited to the region surrounded by the bonding portion 7, the air in the region can be pushed out more favorably by the filler 16.

Further, the element substrate 2 and the sealing substrate 5 may have flexibility. In this case, a flexible organic EL display device can be realized.

(Second Embodiment)
Hereinafter, an organic EL display device according to the second embodiment will be described. In the second embodiment, the configuration of the first embodiment may be used as appropriate within the technically possible range.

FIG. 4 is a partial cross-sectional view of the organic EL display device according to the second embodiment. As shown in FIG. 4, the organic EL display device 1 A includes an element separation unit 21 provided on the element substrate 2. The element isolation unit 21 includes a first portion 22 provided in contact with the second insulating film 13 and a second portion 23 provided on the first portion 22. The element isolation part 21 extends in a strip shape along one side of the main surface 2a, similarly to the element isolation part 4A of the first embodiment. Accordingly, the first portion 22 and the second portion 23 included in the element isolation portion 21 extend in a strip shape along the one side.

The first portion 22 is in contact with the second insulating film 13 and extends substantially parallel to the main surface 2a of the element substrate 2, and the top surface 22b that faces the bottom surface 22a and extends substantially parallel to the bottom surface 22a. And side surfaces 22c and 22d connecting the bottom surface 22a and the top surface 22b. In the width direction of the element isolation part 21, the length of the bottom surface 22a and the length of the top surface 22b are substantially the same. Each of the side surfaces 22c and 22d extends so as to be orthogonal to the bottom surface 22a and the top surface 22b, and the heights of the side surfaces 22c and 22d are substantially the same. Accordingly, the first portion 22 has a substantially rectangular shape in the cross section in the width direction. The height of the first portion 22 is larger than the total thickness of the organic EL layer 14A and the second electrode 15A (or the total thickness of the organic EL layer 14B and the second electrode 15B), for example, 2 μm or more and 5 μm or less. It is. The 1st part 22 is formed with organic resin (1st resin) provided with light transmittances, such as a polyimide, for example.

The second portion 23 is in contact with the top surface 22b of the first portion 22 and extends substantially parallel to the top surface 22b. The top surface 23b faces the bottom surface 23a and extends substantially parallel to the bottom surface 23a. And side surfaces 23c and 23d connecting the bottom surface 23a and the top surface 23b. In the width direction of the element isolation part 21, the length of the bottom surface 23 a and the length of the top surface 23 b are substantially the same and are longer than the lengths of the bottom surface 22 a and the top surface 22 b of the first portion 22. Each of the side surfaces 23c and 23d extends so as to be orthogonal to the bottom surface 23a and the top surface 23b, and the heights of the side surfaces 23c and 23d are substantially the same. Accordingly, the second portion 23 has a substantially rectangular shape in the cross section in the width direction. The height of the second portion 23 is, for example, not less than 2 μm and not more than 5 μm. The second portion 23 is formed of an organic resin (second resin) having light transmissivity such as a novolac resin.

In the width direction of the element isolation portion 21, the side surface 23 c of the second portion 23 is located closer to the organic EL layer 14 A side (or the light emitting element 3 A (see FIG. 3) side) than the side surface 22 c of the first portion 22. Similarly, in the width direction of the element isolation portion 21, the side surface 23d of the second portion 23 is located closer to the organic EL layer 14B side (or the light emitting element 3B (see FIG. 3) side) than the side surface 22d of the first portion 22. . Therefore, both sides of the second portion 23 protrude from the first portion 22 in the width direction of the element isolation portion 21, and the element isolation portion 21 has a so-called overhang shape in the cross section in the width direction. In the width direction of the element isolation part 21, the distance between the side surface 22c and the side surface 23c is 1 μm or more and 10 μm or less, and the distance between the side surface 22d and the side surface 23d is 1 μm or more and 10 μm or less. In this case, the organic EL layers 14A and 14B and the

second electrodes

15A and 15B are satisfactorily separated by the element separation part 21, and the shape of the element separation part 21 is stably maintained.

Here, an example of a method for forming the element isolation portion according to the second embodiment will be described. First, after applying a first resin on the second insulating film 13 by spin coating, a heat treatment at 100 ° C. to 150 ° C. is performed to form a first resin layer having a thickness of about 3 μm on the second insulating film 13. To do. Next, a second resin layer having a thickness of about 3 μm is formed on the first resin layer by applying a second resin on the first resin layer by spin coating and then performing a heat treatment at 100 ° C. to 150 ° C. . In the second embodiment, a non-photosensitive resin is used as the first resin, and a negative resist is used as the second resin. Next, a part of the second resin layer is exposed using a photomask in which stripe-shaped openings are formed. Next, after heat treatment at 100 ° C. to 150 ° C., the second resin layer is developed using TMAH, and the first resin layer is etched. By adjusting the development time of the second resin layer and the etching time of the first resin layer, a part of the first resin layer that overlaps the exposed region of the second resin layer that is difficult to be dissolved is removed by TMAH. Further, by performing heat treatment at 100 ° C. to 150 ° C., a plurality of strip-shaped element isolation portions 21 having an overhang shape and extending in a predetermined direction are formed. In addition, the etching time of the first resin layer is shortened by selecting the second resin so that the solubility of the second resin in the etchant TMAH is lower than the solubility of the first resin in TMAH. Also good.

Next, the operational effects of the second embodiment will be described in comparison with the first embodiment. In the first embodiment, the conductive layer 18 may cover the entire surface of the element isolation portion 4A depending on the manufacturing conditions of the transparent conductive layer forming the

second electrodes

15A and 15B. In this case, in the first embodiment, the

second electrodes

15A and 15B are not separated by the element isolation portion 4A, but become a single transparent conductive layer. Thereby, in 1st Embodiment, light emitting

element

3A, 3B may short-circuit.

On the other hand, according to the organic EL display device 1 A according to the second embodiment, the element separating unit 21 includes the band-shaped first portion 22 provided on the element substrate 2 and the band-shaped first portion 22 provided on the first portion 22. And a second portion 23. Further, both sides of the second portion 23 protrude from the first portion 22 in the width direction of the element isolation portion 21. In this case, the second portion 23 functions as a bag for the first portion 22. For this reason, even if the manufacturing conditions are set so that the coating ratio of the transparent conductive layer to the element substrate 2 is increased, a part of the first part 22 of the element separation part 21 and one part of the second part 23 Part is exposed from the conductive layer 18. Specifically, a region of the first portion 22 adjacent to the second portion 23 of the side surfaces 22c and 22d and a region of the second portion 23 that is not in contact with the first portion 22 of the bottom surface 23a It becomes an exposed area. Thereby, the conductive layer 18 provided on the element isolation part 21 is more easily separated from the

second electrodes

15A and 15B than in the first embodiment. Therefore, in the organic EL display device 1 A according to the second embodiment, even when the manufacturing conditions are changed, the light emitting elements adjacent to each other with the element isolation unit 21 interposed therebetween are favorably separated.

Further, the exposed region of the element isolation part 21 of the second embodiment is covered with the filler 16. For this reason, according to the organic EL display device 1 A according to the second embodiment, the same operational effects as those of the first embodiment are exhibited.

Next, an organic EL display device according to a modification of the second embodiment will be described with reference to FIGS. 5 (a) and 5 (b). FIG. 5A is a partial cross-sectional view of an organic EL display device according to a first modification of the second embodiment. As shown in FIG. 5A, the second portion 23A of the element isolation portion 21A in the organic EL display device 1B has a forward tapered shape in the cross section in the width direction. That is, in the width direction of the element isolation portion 21A, the length of the bottom surface 23a is larger than the length of the top surface 23b, and both sides of the bottom surface 23a protrude from the top surface 23b. In this case, the width of the element isolation portion 21A can be narrower than that of the second portion of the second embodiment. Therefore, the ratio of the light emitting elements provided on the element substrate 2 can be increased. Also in the first modified example, the same operational effects as those of the second embodiment are achieved.

FIG. 5B is a partial cross-sectional view of an organic EL display device according to a second modification of the second embodiment. As shown in FIG. 5B, the second portion 23B of the element isolation portion 21B in the organic EL display device 1C has an inversely tapered shape in the cross section in the width direction. That is, in the width direction of the element isolation portion 21B, the length of the top surface 23b is larger than the length of the bottom surface 23a, and both sides of the top surface 23b protrude from the bottom surface 23a. In this case, the filler 16 can easily flow into the side surfaces 22 c and 22 d of the first portion 22. Therefore, the exposed region of the element isolation portion 21 B is easily covered with the filler 16. Also in the second modified example, the same effects as those of the second embodiment are achieved.

The organic EL display device according to the present invention is not limited to the above-described embodiments and modifications, and various other modifications are possible. For example, the present invention is not applied only to the organic EL display device described above. For example, the present invention may be applied to a segment type organic EL display device.

In the embodiment and the modification, the first electrode is an anode and the second electrode is a cathode. However, the first electrode may be a cathode and the second electrode may be an anode.

In the embodiment and the modification, the organic EL layer is formed without patterning, but is not limited thereto. That is, the organic EL layer may be formed by patterning so as to be provided only in the light emitting element, for example. In this case, for example, the organic EL layer is formed by patterning using a mask. When the organic EL layer is formed using a mask, the element isolation portion may be a portion on which the mask is placed. In the above embodiment, when the organic EL layer is not provided outside the light emitting element, the height of the element separating portion may be larger than the thickness of the second electrode.

DESCRIPTION OF

SYMBOLS

1,1A-1C ... Organic EL display device, 2 ... Element substrate, 3A-3F ... Light emitting element, 4A, 4B, 21, 21A, 21B ... Element separation part, 5 ... Sealing substrate, 7 ... Adhesion part, 11 ... 1st insulating film, 12 ... 1st electrode, 13 ... 2nd insulating film, 14A, 14B ... Organic EL layer, 15A, 15B ... 2nd electrode, 16 ... Filler, 22 ... 1st part, 23, 23A, 23B ... the second part.

Claims

A first substrate;
A first light emitting device and a second light emitting device each provided on the first substrate, each including an organic EL layer;
An element separation unit provided on the first substrate and separating the first light emitting element and the second light emitting element;
A second substrate provided on the first light emitting element, on the second light emitting element, and on the element separating portion;
A filler provided so as to fill a gap between the first substrate and the second substrate;
With
The first substrate, the first light emitting element, the second light emitting element, the element separating portion, the second substrate, and the filler have light transmittance,
The filler includes a light-transmitting desiccant and covers an exposed region of the element isolation part.
Organic EL display device.
The element isolation portion has a strip-shaped first portion provided on the first substrate and a strip-shaped second portion provided on the first portion;
The organic EL display device according to claim 1, wherein both sides of the second portion protrude from the first portion in a width direction of the element isolation portion.
The organic EL display device according to claim 2, wherein the second portion has a cross-sectional forward taper shape in the width direction.
The organic EL display device according to claim 2, wherein the second portion has a cross-section inversely tapered shape in the width direction.
A frame-like adhesive portion that is provided along an edge of the first substrate and that joins the first substrate and the second substrate;
The organic EL display device according to any one of claims 1 to 4, wherein the filler is filled in a region surrounded by the adhesive portion.
The organic EL display device according to any one of claims 1 to 5, wherein the first substrate and the second substrate have flexibility.