WO2012121251A1

WO2012121251A1 - Planar light emitting device

Info

Publication number: WO2012121251A1
Application number: PCT/JP2012/055698
Authority: WO
Inventors: 將有鎌倉; 佐々木　博之
Original assignee: パナソニック株式会社
Priority date: 2011-03-07
Filing date: 2012-03-06
Publication date: 2012-09-13
Also published as: TWI460852B; JPWO2012121251A1; TW201246530A

Abstract

This planar light emitting device includes an organic EL device comprising a light-transmitting substrate, first electrode, light emitting layer, and second electrode. A plurality of first terminal parts is arranged to the side of a right-angled rectangular shaped light emitting part in which the first electrode, light emitting layer and second electrode are stacked and are electrically connected to the first electrode. A plurality of second terminal parts is arranged to the side of the light emitting part and electrically connected to the second electrode. An auxiliary electrode is formed in the vicinity of the peripheral part of the surface on the opposite side from the substrate side for the first electrode and is electrically connected to the first electrode. The m second terminal parts and (m + 1) first terminal parts each along two parallel edges of the light emitting part are arranged such that first terminal parts are positioned on both sides in the direction of width of the second terminal parts, and here, m is an integer of 1 or more. The first terminal parts and second terminal parts are formed from a transparent conductive oxide layer and metal layer, respectively. The value for the total dimension of the width of the first terminal parts divided by the total dimension for the width of the second terminal parts is 0.33 - 0.67.

Description

Planar light emitting device

The present invention relates to a planar light emitting device.

Conventionally, a planar light emitting device having a configuration shown in FIGS. 11 to 14 has been proposed (see Japanese Patent Application Publication No. 2010-198980 (hereinafter referred to as “Document 1”)). This planar light emitting device includes a transparent substrate 101 having a first surface (front) and a second surface (back), an organic EL element 102 formed on one surface of the transparent substrate 101, that is, the second surface, and an organic The light emitting portion 120 of the EL element 102 is covered with a sealing base 103 fixed to the second surface side of the transparent substrate 101 by a nonconductive adhesive.

The above-described planar light emitting device uses the other surface of the transparent substrate 101, that is, the first surface as a light emitting surface (light emitting surface). For example, a glass substrate is used as the transparent substrate 101. In the planar light emitting device, the transparent substrate 101 is formed in a rectangular shape in plan view.

The organic EL element 102 includes a planar anode 121 formed on the second surface side of the transparent substrate 101, and an organic layer 122 formed on the opposite side of the planar anode 121 to the transparent substrate 101 and including at least a light emitting layer; The organic layer 122 is provided with a planar cathode 123 formed on the side opposite to the planar anode 121 side and facing the planar anode 21. Here, in the organic EL element 102, the planar anode 121 is made of a transparent conductive film (for example, an ITO film, an IZO film, etc.) having a square shape in plan view, and the planar cathode 123 is a metal film having a square shape in plan view. Become. The metal film constituting the planar cathode 123 is made of an Al film, but it is not limited to the Al film, and may be made of a metal having a smaller resistivity and a smaller work function than a transparent conductive film, For example, it is described that it may be configured by a laminated film of an Mg film and an Ag film. The organic layer 122 is formed in a square shape in plan view.

In addition, the organic EL element 102 is formed on the second surface side of the transparent substrate 101 at both ends in the longitudinal direction of the transparent substrate 101 and is electrically connected to the planar anode 121, and a transparent substrate A cathode feeding portion 125 formed on the second surface side of the transparent substrate 101 at both ends in the longitudinal direction of the 101 and electrically connected to the planar cathode 123 is provided. Here, in the organic EL element 102, each of the anode power supply unit 124 and the cathode power supply unit 125 is made of a transparent conductive film (for example, an ITO film, an IZO film, etc.).

The above-described organic EL element 102 is formed such that two positive

electrode feeding parts

124 and 124 are separated in the short direction of the transparent substrate 101 at both ends in the longitudinal direction of the transparent substrate 101. One cathode feeding portion 125 is disposed between two anode feeding portions 124 adjacent to each other in the hand direction.

In the planar cathode 123, the planar cathode 123 extends from the central portion in the longitudinal direction of one side edge along the short direction of the transparent substrate 101 and extends in the direction orthogonal to the one side edge. It is electrically connected to the cathode power supply unit 125 via the same. Here, the planar cathode 123 and the lead wiring 123b are simultaneously formed with the same material and the same thickness.

Further, the organic EL element 102 is formed on the second surface side of the transparent substrate 101 over the entire circumference of the surface of the planar anode 121 on the opposite side to the transparent substrate 101 side. And a frame-shaped auxiliary electrode 126 for anodes connected in the same manner. Here, the frame-shaped auxiliary electrode 126 for an anode is formed in a square frame shape in plan view. The organic EL element 102 further includes a cathode feeding portion auxiliary electrode 128 stacked on the side opposite to the transparent substrate 101 in the cathode feeding portion 125 and electrically connected to the cathode feeding portion 125. Here, the frame-like auxiliary electrode 126 for the anode and the auxiliary electrode 128 for the cathode feeding portion are constituted by a laminated film of a Cr film and an Au film.

In addition, the anode frame-shaped auxiliary electrode 126 described above is continuously and integrally formed with an anode power feeding portion auxiliary electrode 127 which is stacked on the anode power feeding portion 124 and electrically connected to the anode power feeding portion 124.

In the planar light emitting device described above, the planar anode 121, the anode feeding portion 124 and the cathode feeding portion 125 are simultaneously formed with the same transparent conductive material (for example, ITO, IZO, etc.) in the same thickness. In the planar light emitting device, the anode feeding portion auxiliary electrode 127 and the cathode feeding portion auxiliary electrode 128 are formed of the same material and in the same thickness. The planar light emitting device has a total dimension of the width of the anode-side external connection electrode E1 composed of the anode feeding portion 124 and the anode feeding portion auxiliary electrode 127, the cathode feeding portion 125, and the cathode feeding portion auxiliary electrode 128. And the total dimension of the width of the cathode-side external connection electrode E2 composed of and is set to the same value.

Further, the organic EL element 102 is provided with an insulating film 129 having a square frame shape in plan view covering the side edges of the frame auxiliary electrode 126 for the anode and the planar anode 121 on the second surface side of the transparent substrate 101. The organic EL element 102 is configured such that a short circuit between the frame auxiliary electrode 126 for anode and the planar anode 121 and the planar cathode 123 is prevented by the insulating film 129. Document 1 describes that, for example, polyimide, novolac resin, epoxy resin or the like may be adopted as the material of the insulating film 129.

Moreover, in the planar light emitting device, an epoxy resin containing a filler is used as a sealing material which constitutes the above-mentioned nonconductive adhesive.

By the way, in order to light the organic EL element 102 with high luminance in the above-described planar light emitting device, it is necessary to flow a larger current. However, in the planar light emitting device described above, the metal material is used for each of the auxiliary electrode 127 for the anode power supply portion in the anode side external connection electrode E1, the auxiliary electrode 128 for the cathode power supply portion in the cathode side external connection electrode E2, and the planar cathode 123. There is a concern that the reliability may be reduced due to electromigration.

The present invention has been made in view of the above problems, and an object thereof is to provide a planar light emitting device capable of improving the reliability while suppressing the increase of the drive voltage.

The planar light emitting device of the present invention comprises a translucent substrate (1) and an organic EL element (2) formed on one surface side of the translucent substrate (1). The organic EL element (2) is provided with a first electrode (21) disposed on the one surface side of the translucent substrate (1) and formed of a transparent conductive film, and the translucent property of the first electrode (21) A light emitting layer (220) made of an organic material and disposed on the side opposite to the substrate (1) side, and a metal film placed on the side opposite to the first electrode (21) side of the light emitting layer (220) The first electrode (21) is disposed on the side of a light emitting portion in which two electrodes (23), the first electrode (21), the light emitting layer (220), and the second electrode (23) overlap. A plurality of first terminal portions (T1) connected to each other, a plurality of second terminal portions (T2) disposed laterally of the light emitting portion and electrically connected to the second electrode (23); The material of the first electrode (21) is made of a material having a specific resistance smaller than that of the first electrode (21). The gender substrate (1) side and a side opposite the formed near the peripheral portion of the surface of the first electrode (21) electrically connected to an auxiliary electrode (26). The planar view shape of the said light emission part is right-angled quadrilateral shape. The m second terminal portions (T2) and the (m + 1) first terminal portions (T1) are arranged along the predetermined parallel two sides of the light emitting portion having the right-angled quadrilateral shape, and the second terminals. It arrange | positions so that a 1st terminal part (T1) may be located in the both sides of the width direction of a part (T2), and m is an integer greater than or equal to 1 here. Each of the first terminal portion (T1) and the second terminal portion (T2) has a laminated structure of a transparent conductive oxide layer and a metal layer. A value obtained by dividing the total dimension of the width of the first terminal portion (T1) by the total dimension of the width of the second terminal portion (T2) is 0.33 or more and 0.67 or less.

In one embodiment, a value obtained by dividing the total dimension of the width of the first terminal portion (T1) by the total dimension of the width of the second terminal portion (T2) is 0.33 or more and less than 0.5.

In one embodiment, the organic EL element (2) is an insulating film covering side edges of the auxiliary electrode (26) and the first electrode (21) on the one surface side of the translucent substrate (1). And 29).

In one embodiment, m ≧ 2.

In the planar light emitting device of the present invention, it is possible to improve the reliability while suppressing the increase of the drive voltage.

The preferred embodiments of the present invention will be described in more detail. Other features and advantages of the present invention will be better understood in conjunction with the following detailed description and the accompanying drawings.
It is a rear view of the planar light-emitting device of embodiment. FIG. 2A is a schematic cross-sectional view taken along the line BB ′ of FIG. 1, and FIG. 2B is a schematic cross-sectional view taken along the line CC ′ of FIG. FIG. 6 is a schematic cross-sectional view taken along the line DD ′ of FIG. 1 showing the planar light emitting device of the above. It is a principal process top view for explaining the manufacturing method same as the above. It is a principal process top view for explaining the manufacturing method same as the above. It is a principal process top view for explaining the manufacturing method same as the above. It is a principal process top view for explaining the manufacturing method same as the above. It is a principal process top view for explaining the manufacturing method same as the above. It is a principal process top view for explaining the manufacturing method same as the above. It is a figure which shows the simulation result of the characteristic of a planar light-emitting device same as the above. 11A shows a rear view, FIG. 11B shows a schematic cross-sectional view taken along the line BB 'in FIG. 11A, and FIG. 11C shows a schematic cross-sectional view taken along the line CC' in FIG. 11A. It is a front view of a planar light-emitting device same as the above. It is a principal part enlarged view of FIG. 11B. It is a principal part enlarged view of FIG. 11C.

Hereinafter, the planar light emitting device of the present embodiment will be described based on FIGS. 1 to 3.

The planar light emitting device A includes the organic EL element module 3 and the cover substrate 5. The organic EL element module 3 includes a translucent substrate 1 having a first surface (front) and a second surface (back), and an organic EL device formed on one surface of the translucent substrate 1, that is, the second surface. And two. In one example, the translucent substrate 1 has a rectangular shape in which two have four straight sides longer than the other two, and two long sides are along the first direction, and the light emitting portion of the organic EL element 2 is The numeral 20 is in the form of a quadrangle having four right angles (hereinafter referred to as a "right square"). In the example of FIG. 1, the light emission part 20 is square shape. The cover substrate 5 has a first surface and a second surface, and the organic EL element module 3 is attached to the organic EL element module 3 via the bonding portion 4 so that the first surface is disposed opposite to the second surface side of the translucent substrate 1. It is fixed. In addition, the planar light emitting device A is the heat spreader plate 6 (on the second surface of the cover substrate 5 in the example of FIGS. 2A and 2B) on the opposite side of the cover substrate 5 to the organic EL element 2 side. 2 and 3). Here, in the cover substrate 5, a recess 51 is formed on the surface (first surface) facing the organic EL element module 3 so as to cover the whole of the organic EL element 2. The peripheral portion 51 (the outer peripheral portion of the first surface) is bonded to the organic EL element module 3 over the entire periphery. Thus, in the planar light emitting device A, the light emitting unit 20 of the organic EL element 2 is housed in an airtight space surrounded by the light transmitting substrate 1, the cover substrate 5, and the bonding unit 4. In the planar light emitting device A, a hygroscopic material (not shown) that adsorbs moisture is attached to the inner bottom surface of the recess 51 in the cover substrate 5.

The organic EL element 2 is disposed on the second surface side of the translucent substrate 1 and is made of a transparent conductive film, and the organic electrode is disposed on the opposite side to the translucent substrate 1 side of the first electrode 21. And a second electrode 23 disposed on the opposite side of the organic EL layer 22 from the side of the first electrode 21 and made of a metal film. In the example of FIGS. 2A and 2B, the first electrode 21 is a right quadrilateral shape having a first surface (lower surface) and a second surface (upper surface), and the first surface of the first electrode 21 is a translucent substrate 1. It is formed on the second surface of the translucent substrate 1 so as to be bonded to the second surface. The organic EL layer 22 has a first surface (lower surface) and a second surface (upper surface), and the first electrode 21 is bonded such that the first surface of the organic EL layer 22 is bonded to the second surface of the first electrode 21. Is formed on the second surface of the The second electrode 23 has a first surface (lower surface) and a second surface (upper surface), and the organic EL layer 22 is formed such that the first surface of the second electrode 23 is bonded to the second surface of the organic EL layer 22. Is formed on the second surface of the

The organic EL element 2 also includes a plurality of first terminal portions T1 and a plurality of second terminal portions T2. Each first terminal portion T1 is disposed on the side of the light emitting unit 20 where the first electrode 21, the organic EL layer 22, and the second electrode 23 overlap, and is electrically connected to the first electrode 21. Each second terminal portion T2 is disposed to the side of the light emitting unit 20, and is electrically connected to the second electrode 23 via a lead wire 23b extended from the second electrode 23. In the example of FIGS. 1 and 2A, the plurality of first terminal portions T1 (24 and 27) are formed so as to be formed directly on the second surface of the translucent substrate 1 and directly coupled to the first electrode 21. It is disposed at each of both ends in the longitudinal direction of the flexible substrate 1. In the example of FIGS. 1 and 2B, the plurality of second terminal portions T2 (25 and 28) are formed directly on the second surface of the translucent substrate 1 and electrically connected to the second electrode 23 through the lead wiring 23b. Are disposed at each of both ends in the longitudinal direction of the translucent substrate 1.

Further, the organic EL element 2 is provided with an auxiliary electrode 26. The auxiliary electrode 26 is made of a material having a smaller specific resistance than the first electrode 21 and is formed along the periphery of the surface of the (at least) first electrode 21 opposite to the light transmitting substrate 1 side. The first electrode 21 is electrically connected. In the example of FIGS. 1 to 3, the auxiliary electrode 26 has a rectangular quadrilateral frame shape, and is directly on the second surface of the first electrode 21 (and each portion of the plurality of first terminal portions T1 (24)). It is formed. In addition, the organic EL element 2 includes the insulating film 29, which covers the entire auxiliary electrode 26 and also covers the side edge of the first electrode 21 in the vicinity of the auxiliary electrode 26. It is formed on the surface side. The insulating film 29 prevents the short circuit between the auxiliary electrode 26 and the first electrode 21 and the second electrode 23 of the organic EL element 2. The auxiliary electrode 26 is a rectangular quadrilateral frame along the entire periphery of the second surface of the first electrode 21. However, the auxiliary electrode 26 does not necessarily have to be a rectangular quadrilateral frame. As long as they are electrically connected to 21, they may be divided into a partially opened shape (for example, a C-shape or a U-shape) or a plurality.

The above-described light emitting unit 20 of the organic EL element 2 is a region where the light transmitting substrate 1, the first electrode 21, the organic EL layer 22 (light emitting layer 220), and the second electrode 23 overlap in the thickness direction of the light transmitting substrate 1. The region other than the light emitting unit 20 in the organic EL element 2 is a non-light emitting unit. Here, the organic EL element 2 has the respective shapes in plan view of the first electrode 21, the organic EL layer 22 and the second electrode 23 as a right quadrilateral shape (square in the illustrated example) smaller than the translucent substrate 1. is there. Therefore, the plan view shape of the light emitting unit 20 is a right quadrilateral shape (square in the illustrated example) smaller than the translucent substrate 1. In addition, the auxiliary electrode 26 has a frame shape having a rectangular quadrangle as viewed in plan. In addition, the insulating film 29 has a frame shape having a rectangular quadrilateral shape in plan view.

The organic EL element 2 includes m second terminal portions T2 and [m + 1] first terminal portions T1 along each of two parallel sides of the light emitting unit 20 in the second direction orthogonal to the first direction. The first terminal portions T1 are disposed on both sides in the width direction of the second terminal portions T2 (both sides of the second terminal portions T2 in the second direction). Here, m is an integer of 1 or more. In the example of FIG. 1, m is "2". Therefore, in the example shown in FIG. 1, the plurality of first terminal portions T1 and the plurality of second terminal portions T2 are provided at each of both end portions in the longitudinal direction of the translucent substrate 1. Specifically, in each of both ends of the translucent substrate 1 in the first direction, the three first terminal portions T1 of the organic EL element 2 are in the lateral direction of the translucent substrate 1 (in the second direction). The second terminal portions T2 are disposed between the first terminal portions T1 adjacent to each other in the second direction.

Here, the first terminal portion T1 includes a transparent conductive oxide layer 24 (hereinafter also referred to as "first layer 24" as a first transparent conductive oxide layer) and a metal layer 27 (hereinafter "first metal layer 27"). Also has a laminated structure of The second terminal portion T2 includes a transparent conductive oxide layer 25 (hereinafter also referred to as "second layer 25" as a second transparent conductive oxide layer) and a metal layer 28 (hereinafter also referred to as "second metal layer 28") And a laminated structure of In the example of FIG. 2A, the plurality of first layers 24 of the plurality of first terminal portions T1 are formed so as to be formed directly on the second surface of the translucent substrate 1 and directly coupled to the first electrode 21. Each of the plurality of metal layers 27 is disposed at each of both ends in the longitudinal direction of the elastic substrate 1 and is formed directly on the end of the first layer 24 in its own first terminal portion T1. Further, in the example of FIG. 2B, the plurality of second layers 25 of the plurality of second terminal portions T2 are formed directly on the second surface of the translucent substrate 1 and are connected to the second electrode 23 through the lead wiring 23b. Each of the plurality of metal layers 28 is disposed at an end of the second layer 25 of its own second terminal portion T2 so as to be electrically connected to each of both ends in the longitudinal direction of the translucent substrate 1. It is formed right above the part.

Further, the planar shape of the heat spreader plate 6 is a right quadrilateral shape (square shape in the illustrated example) which is smaller than the cover substrate 5 and larger than the light emitting portion 20.

Hereinafter, each component of the planar light emitting device A will be described in detail.

The planar light emitting device A uses the first surface of the translucent substrate 1 as a light emitting surface (light emitting surface). Therefore, in the planar light emitting device A, in the first surface of the light transmitting substrate 1, the area onto which the first electrode 21, the organic EL layer 22, and the second electrode 23 are projected overlapping is the light emitting surface. . The translucent substrate 1 has a rectangular shape in a plan view, but the shape is not limited to this, and may be, for example, a square shape.

Although a glass substrate is used as the translucent substrate 1, the present invention is not limited to this, and for example, a plastic substrate may be used. As the glass substrate, for example, a soda lime glass substrate, an alkali-free glass substrate or the like can be used. Further, as the plastic substrate, for example, a polyethylene terephthalate (PET) substrate, a polyethylene naphthalate (PEN) substrate, a polyether sulfone (PES) substrate, a polycarbonate (PC) substrate or the like may be used. When a plastic substrate is used, a SiON film, a SiN film or the like may be formed on the surface of the plastic substrate to suppress the permeation of moisture.

When a glass substrate is used as the translucent substrate 1, the unevenness of the second surface of the translucent substrate 1 may cause the generation of a leak current of the organic EL element 2 (a cause of deterioration of the organic EL element 2) Can be For this reason, when using a glass substrate as the translucent substrate 1, it is preferable to prepare a glass substrate for element formation polished with high accuracy so that the surface roughness of the second surface is reduced. As for the surface roughness of the second surface of the translucent substrate 1, it is preferable to set the arithmetic average roughness Ra defined by JIS B 0601-2001 (ISO 4287-1997) to several nm or less. On the other hand, when a plastic substrate is used as the light-transmissive substrate 1, one having an arithmetic average roughness Ra of several nm or less on the second surface can be obtained at low cost without particularly performing high-precision polishing. It is possible.

In the organic EL element 2, the first electrode 21 constitutes an anode, and the second electrode 23 constitutes a cathode. In the organic EL element 2, the organic EL layer 22 interposed between the first electrode 21 and the second electrode 23 is, in order from the first electrode 21 side, a hole transport layer, the above-mentioned light emitting layer, an electron transport layer, It has an electron injection layer.

The laminated structure of the organic EL layer 22 described above is not limited to the above-mentioned example, and for example, a single layer structure of the light emitting layer 220, a laminated structure of a hole transporting layer, a light emitting layer 220 and an electron transporting layer, a hole transporting layer A stacked structure with the light emitting layer 220 or a stacked structure with the light emitting layer 220 and the electron transporting layer may be used. In addition, a hole injection layer may be interposed between the first electrode 21 and the hole transport layer. The light emitting layer 220 may have a single layer structure or a multilayer structure. For example, when the desired emission color is white, three dopant dyes of red, green and blue may be doped in the light emitting layer 220, and the blue hole transporting light emitting layer and the green electron transport may be doped. It is possible to adopt a laminated structure of a luminescent light emitting layer and a red electron transporting light emitting layer, or a laminated structure of a blue electron transporting light emitting layer, a green electron transporting light emitting layer and a red electron transporting light emitting layer. It is also good. In addition, an organic EL layer 22 having a function of emitting light when a voltage is applied by being sandwiched between the first electrode 21 and the second electrode 23 is one light emitting unit, and a plurality of light emitting units are intermediates having light transparency and conductivity. Multi-unit structure in which layers are stacked and electrically connected in series (that is, a structure including a plurality of light emitting units overlapping in the thickness direction between one first electrode 21 and one second electrode 23) May be adopted.

The first electrode 21 constituting the anode is an electrode for injecting holes into the light emitting layer 220, and has a large work function (for example, compared to the second electrode 23). It is preferable to use an electrode material made of a mixture, and it is preferable to use one having a work function of 4 eV or more and 6 eV or less so that the difference from the HOMO (Highest Occupied Molecular Orbital) level is not too large. Examples of the electrode material of the first electrode 21 include ITO (Indium Tin Oxide), tin oxide, zinc oxide, IZO (Indium Zinc Oxide), copper iodide and the like, conductive polymers such as PEDOT and polyaniline, and any acceptor and the like. And conductive light transmitting materials such as conductive polymers and carbon nanotubes. Here, the first electrode 21 may be formed as a thin film on the second surface side of the translucent substrate 1 by, for example, a sputtering method, a vacuum evaporation method, a coating method, or the like.

The sheet resistance of the first electrode 21 is preferably several hundred ohms / square or less, and more preferably 100 ohms / square or less. Here, the film thickness of the first electrode 21 varies depending on the light transmittance of the first electrode 21, the sheet resistance, etc., but it is preferable to set it in a range of 500 nm or less, preferably 10 nm to 200 nm.

Further, the second electrode 23 constituting the cathode is an electrode for injecting electrons into the light emitting layer 220, and has a small work function (for example, compared to the first electrode 21), a metal, an alloy, an electrically conductive compound, It is preferable to use an electrode material made of a mixture of these materials, and it is preferable to use one having a work function of 1.9 eV or more and 5 eV or less so that the difference with the lowest unoccupied molecular orbital (LUMO) level is not too large. As an electrode material of the second electrode 23, for example, aluminum, silver, magnesium, gold, copper, chromium, molybdenum, palladium, tin, etc., and alloys of these with other metals, such as magnesium-silver mixture, magnesium-indium Mixtures, aluminum-lithium alloys may be mentioned by way of example. In addition, metal, metal oxide, etc., and a mixture of these with other metals, for example, an extremely thin film of aluminum oxide (here, a thin film of 1 nm or less capable of flowing electrons by tunnel injection) and aluminum A laminated film with a thin film can also be used. As an electrode material of the second electrode 23, a metal having a high reflectance to light emitted from the light emitting layer 220 and a low resistivity is preferable, and aluminum or silver is preferable.

As a material of the light emitting layer 220, any material known as a material for an organic EL element can be used. For example, anthracene, naphthalene, pyrene, tetracene, coronene, perylene, phthaloperylene, naphthaloperylene, diphenyl butadiene, tetraphenyl butadiene, coumarin, oxadiazole, bisbenzoxazoline, bisstyryl, cyclopentadiene, quinoline metal complex, tris (8-hydroxyki Norinate) aluminum complex, tris (4-methyl-8-quinolinate) aluminum complex, tris (5-phenyl-8-quinolinate) aluminum complex, aminoquinoline metal complex, benzoquinoline metal complex, tri- (p-terphenyl-) 4-yl) amine, 1-aryl-2,5-di (2-thienyl) pyrrole derivative, pyran, quinacridone, rubrene, distyrylbenzene derivative, distyrylarylene derivative, distyryl And amine derivatives, and various fluorescent pigments, but include those including a material system and its derivatives described above, not limited to these. In addition, it is also preferable to appropriately mix and use a light emitting material selected from among these compounds. Moreover, not only compounds that produce fluorescence, as typified by the above compounds, but also material systems that emit light from spin multiplets, such as phosphorescent materials that produce phosphorescence, and a site made of them in a part of the molecule Compounds can also be suitably used. The light emitting layer 220 made of these materials may be deposited by a dry process such as evaporation or transfer, or may be deposited by a wet process such as spin coating, spray coating, die coating or gravure printing. It may be a membrane.

The material used for the above-described hole injection layer can be formed using a hole injection organic material, a metal oxide, a so-called acceptor organic material or inorganic material, a p-doped layer or the like. The hole-injecting organic material is a material having a hole-transporting property, a work function of about 5.0 to 6.0 eV, and a strong adhesion to the first electrode 21. For example, CuPc, starburst amine, etc. are examples thereof. The hole-injectable metal oxide is, for example, a metal oxide containing any of molybdenum, rhenium, tungsten, vanadium, zinc, indium, tin, gallium, titanium, and aluminum. In addition, oxides of a plurality of metals other than the oxides of only one metal, such as indium and tin, indium and zinc, aluminum and gallium, gallium and zinc, titanium and niobium, etc. It may be In addition, the hole injection layer made of these materials may be formed by a dry process such as evaporation or transfer, or formed by a wet process such as spin coating, spray coating, die coating, or gravure printing. It may be a membrane.

The material used for the hole transport layer can be selected, for example, from the group of compounds having a hole transportability. Examples of the compound of this type include 4,4′-bis [N- (naphthyl) -N-phenyl-amino] biphenyl (α-NPD), N, N′-bis (3-methylphenyl)-(1 1,1′-biphenyl) -4,4′-diamine (TPD), 2-TNATA, 4,4 ′, 4 ′ ′-tris (N- (3-methylphenyl) N-phenylamino) triphenylamine (MTDATA) Arylamine compounds, amine compounds containing a carbazole group, with 4,4′-N, N′-dicarbazole biphenyl (CBP), spiro-NPD, spiro-TPD, spiro-TAD, TNB and the like as representative examples Although amine compounds containing a fluorene derivative can be mentioned, it is possible to use any generally known hole transport material.

The material used for the electron transport layer can be selected from the group of compounds having electron transportability. Examples of this type of compound include metal complexes known as electron transporting materials such as Alq ₃ and compounds having a heterocycle such as phenanthroline derivatives, pyridine derivatives, tetrazine derivatives, oxadiazole derivatives, etc. Rather, it is possible to use any of the commonly known electron transport materials.

The material of the electron injection layer is, for example, metal fluorides such as lithium fluoride and magnesium fluoride, metal halides such as metal chlorides represented by sodium chloride and magnesium chloride, aluminum, cobalt, zirconium, etc. Oxides, nitrides, carbides, oxynitrides, etc. of various metals such as titanium, vanadium, niobium, chromium, tantalum, tungsten, manganese, molybdenum, ruthenium, iron, nickel, copper, gallium, zinc, silicon etc. eg aluminum oxide It is arbitrarily selected from those to be insulators such as magnesium oxide, iron oxide, aluminum nitride, silicon nitride, silicon carbide, silicon oxynitride, boron nitride, etc., silicon compounds such as SiO ₂ and SiO, carbon compounds, etc. Can be used. These materials can be formed into thin films by vacuum evaporation, sputtering, or the like.

The material of the lead-out wiring 23b is the same as that of the second electrode 23. Here, the thickness of the lead wire 23 b is set to the same thickness as that of the second electrode 23. The lead-out wiring 23 b is formed continuously with the second electrode 23. Therefore, the planar light emitting device A of this embodiment can simultaneously form the lead-out wiring 23 b and the second electrode 23 at the time of manufacture. Further, the lead-out wiring 23b is extended to a portion formed inside the bonding region 25a with the bonding portion 4 in the second layer 25 of the second terminal portion T2. The width (wiring width) dimension of the lead wire 23b prevents the short circuit with the first terminal portion T1 and secures a predetermined insulation distance between the first terminal portion T1 and the second terminal portion T2. It is set to a value slightly smaller than the width dimension of. The width dimension of the lead-out wiring 23b is preferably equal to or less than the width of the second terminal portion T2, but a value as large as possible is preferable in order to enhance the electromigration resistance.

The material of the first layer 24 and the second layer 25 is a transparent conductive oxide (TCO), and for example, ITO, AZO, GZO, IZO, etc. can be adopted. The materials of the first layer 24 and the second layer 25 are the same as those of the first electrode 21, and the first electrode 21, the first layer 24 and the second layer 25 have the same thickness.

In addition, the material of the first metal layer 27 and the second metal layer 28 is, for example, a metal such as aluminum, silver, gold, copper, chromium, molybdenum, aluminum, palladium, tin, lead, magnesium, or at least one of these metals. Alloys containing seeds are preferred. The first metal layer 27 and the second metal layer 28 are not limited to a single layer structure, and may have a multilayer structure. For example, the first metal layer 27 and the second metal layer 28 can adopt a three-layer structure of MoNb layer / AlNd layer / MoNb layer. In the three-layer structure, it is preferable that the lower MoNb layer be provided as an adhesive layer with the base, and the upper MoNb layer be provided as a protective layer for the AlNd layer. Further, in the present embodiment, the material of the first metal layer 27 and the material of the second metal layer 28 are the same, and the first metal layer 27 and the second metal layer 28 are set to the same thickness. The first metal layer 27 and the second metal layer 28 may employ the same material as the second electrode 23.

Moreover, as a material of the auxiliary electrode 26, for example, metals such as aluminum, silver, gold, copper, chromium, molybdenum, aluminum, palladium, tin, lead, magnesium and alloys containing at least one of these metals are preferable. . The auxiliary electrode 26 is not limited to a single layer structure, and may have a multilayer structure. For example, the auxiliary electrode 26 can adopt a three-layer structure of MoNb layer / AlNd layer / MoNb layer. In this three-layer structure, the lower MoNb layer is preferably provided as an adhesive layer with the base, and the upper MoNb layer is preferably provided as a protective layer for the AlNd layer. In the planar light emitting device A of the present embodiment, the material of the auxiliary electrode 26 and the materials of the first metal layer 27 and the second metal layer 28 are the same. As a result, in the planar light emitting device A of the present embodiment, it is possible to simultaneously form the auxiliary electrode 26 and the first metal layer 27 and the second metal layer 28 at the time of manufacture, thereby achieving cost reduction.

In addition, as a material of the insulating film 29, for example, polyimide is adopted, but not limited to this, for example, novolac resin, epoxy resin, etc. can be adopted.

In the organic EL element 2 described above, the region where only the organic EL layer 22 intervenes between the first electrode 21 and the second electrode 23 constitutes the light emitting unit 20 described above, and the planar shape of the light emitting unit 20 is insulating It has a right quadrilateral shape (square shape in the illustrated example) which is the same as the shape of the inner peripheral edge of the film 29. Here, in the planar light emitting device A, a portion other than the light emitting portion 20 of the organic EL element 2 is a non-light emitting portion in plan view.

Further, although a glass substrate is used as the cover substrate 5, the present invention is not limited to this, and for example, a plastic substrate may be used. As the glass substrate, for example, a soda lime glass substrate, an alkali-free glass substrate or the like can be used. Further, as the plastic substrate, for example, a polyethylene terephthalate (PET) substrate, a polyethylene naphthalate (PEN) substrate, a polyether sulfone (PES) substrate, a polycarbonate (PC) substrate or the like may be used. When a plastic substrate is used, a SiON film, a SiN film or the like may be formed on the surface of the plastic substrate to suppress the permeation of moisture.

The cover substrate 5 is bonded to the organic EL element module 3 via the bonding portion 4 as described above. Here, as shown in FIGS. 2A, 2B and 3, the interface between the bonding portion 4 and the organic EL element module 3 is the first interface between the bonding portion 4 and the first terminal portion T1, the bonding portion 4 and the second There is a second interface with the terminal portion T2 and a third interface with the bonding portion 4 and the translucent substrate 1.

Although an epoxy resin is used as the material of the bonding portion 4, the material is not limited to this, and for example, an acrylic resin, frit glass, or the like may be adopted. As an epoxy resin and an acrylic resin, an ultraviolet curing thing may be used and a thermosetting thing may be used. Further, as a material of the bonding portion 4, a material in which a filler (for example, silica, alumina or the like) is contained in an epoxy resin may be used.

As the above-mentioned hygroscopic material, for example, a calcium oxide desiccant (a getter into which calcium oxide is kneaded) or the like can be used.

As a material of the heat spreader plate 6, a metal having a high thermal conductivity among various metals is preferable, and copper is adopted. The material of the heat spreader plate 6 is not limited to copper, and may be, for example, aluminum, gold or the like. In addition, as the heat spreader 6, you may use metal foil (for example, copper foil, aluminum foil, a gold foil etc.).

Further, in the planar light emitting device A of the present embodiment, the opening size of the recess 51 in the cover substrate 5 is set larger than the size of the outer peripheral shape of the insulating film 29, and the peripheral portion of the cover substrate 5 Is bonded to the organic EL element module 3 via the Thus, the planar light emitting device A can improve the moisture resistance because the first electrode 21 and the second electrode 23 are not exposed. Here, it is a part of each of 1st terminal area T1 and 2nd terminal area T2 that is exposed among organic EL elements 2. As shown in FIG.

Here, although the first terminal portion T1 has the laminated structure of the first layer 24 and the first metal layer 27 as described above, the bonding region 24a constituted only by the first layer 24 is The first terminal portion T1 is provided along the circumferential direction of the joint portion 4 over the entire length in the width direction of the first terminal portion T1. In addition, although the second terminal portion T2 has the laminated structure of the second layer 25 and the second metal layer 28 as described above, the joining region 25a constituted only by the second layer 25 is joined. The second terminal portion T2 is provided along the circumferential direction of the portion 4 over the entire length in the width direction of the second terminal portion T2. Therefore, the first interface between the bonding portion 4 and the first terminal portion T1 is constituted by the interface between the bonding portion 4 and the first layer 24, and the second interface between the bonding portion 4 and the second terminal portion T2 is bonding An interface between the portion 4 and the second layer 25 is formed. Thereby, the planar light emitting device A of the present embodiment can improve the bonding strength between the bonding portion 4 and the first terminal portion T1 and the second terminal portion T2, and further, the first metal layer 27 and the first metal layer 27 and the It becomes possible to prevent the occurrence of oxidation due to the time-dependent change of the two-metal layer 28 and change in the state of the first interface and the second interface, and it becomes possible to improve the reliability.

Moreover, in the planar light emitting device A of the present embodiment, by including the heat equalizing plate 6, it is possible to achieve soaking of the temperature of the light emitting portion 20 of the organic EL element 2, so that It becomes possible to reduce the in-plane variation of temperature, and to improve the heat dissipation. Thus, in the planar light emitting device A, the temperature rise of the organic EL element 2 can be suppressed, and the life can be extended when the input power is increased to achieve high luminance.

Hereinafter, a method of manufacturing the planar light emitting device A of the present embodiment will be described with reference to FIGS. 4 to 9.

First, on the second surface side of the light-transmissive substrate 1 made of a glass substrate, the first electrode 21, the first layer 24, and the same made of the same transparent conductive oxide (for example, ITO, AZO, GZO, IZO, etc.) The second layer 25 is simultaneously formed by vapor deposition, sputtering or the like to obtain the structure shown in FIG. That is, each first layer 24 is continuous with the first electrode 21 without a gap, while each second layer 25 is separated from the first electrode 21 with a gap (FIGS. 2A, 2B and 4). reference).

Next, the auxiliary electrode 26, the first metal layer 27 and the second metal layer 28 made of, for example, the same metal material or the like are formed on the second surface side of the translucent substrate 1 using a vapor deposition method, a sputtering method, or the like. By forming simultaneously, the structure shown in FIG. 5 is obtained.

Subsequently, an insulating film 29 made of a resin material (for example, polyimide, novolac resin, epoxy resin or the like) is formed on the second surface side of the translucent substrate 1 to obtain a structure shown in FIG.

Thereafter, the organic EL layer 22 is formed on the second surface side of the translucent substrate 1 by, for example, a vapor deposition method to obtain a structure shown in FIG. The method of forming the organic EL layer 22 is not limited to the vapor deposition method, and may be a coating method, for example, and may be appropriately selected according to the material of the organic EL layer 22.

Subsequently, the second electrode 23 and the lead wire 23b made of the same metal material (for example, aluminum, silver, etc.) are formed on the second surface side of the translucent substrate 1 using a vapor deposition method, a sputtering method, or the like. Thus, the organic EL element module 3 having the structure shown in FIG. 8 is obtained.

Thereafter, the material (for example, epoxy resin, acrylic resin, glass frit, and the like) 4a of the bonding portion 4 is applied to the second surface side of the translucent substrate 1 by a dispenser or the like to obtain a structure shown in FIG. Here, in the application step of applying the material 4 a of the bonding portion 4, the material 4 a is applied to the peripheral portion of the organic EL element module 3 in the form of a rectangular quadrilateral, but the cover is not the organic EL element module 3. The material 4 a of the bonding portion 4 may be applied to the periphery of the recess 51 in the substrate 5 in a rectangular frame shape. In addition, the coating apparatus which apply | coats the material 4a of the junction part 4 may use not only a dispenser but a screen printing apparatus, a die coater, a slit coater etc., for example.

In any case, after the material 4a of the joint 4 is applied, the cover substrate 5 to which the moisture absorbing material and the heat spreader plate 6 have been previously attached is overlapped, and the material 4a of the joint 4 is cured from an uncured state. By bonding, the planar light emitting device A having the structure shown in FIG. 1 is obtained. When the material 4a of the joint 4 is to be cured from the uncured state, if the material 4a is of the ultraviolet curing type, the material 4a is cured by irradiating it with ultraviolet light. When the material 4a of the joint 4 is a thermosetting type, the material 4a is cured by heating the material 4a. As the hygroscopic material, it is possible to use, for example, a seal-type desiccant or a coating-type desiccant, and the curing step in the case of using the coating-type desiccant is a combination with the material 4 a of the joint 4 Depending on the situation, it may be performed either alone before overlaying the cover substrate 5 and the organic EL element module 3 or in the curing step of curing the material 4 a of the bonding portion 4. As a method of applying the coating-type desiccant, for example, a method using a dispenser, a screen printing apparatus, a metal mask, a die coater, a slit coater or the like can be adopted.

In the planar light emitting device A of the present embodiment, the planar size of the light emitting unit 20 is set to 80 mm, but not limited to this, for example, it may be appropriately set in the range of about 30 to 300 mm. Moreover, although the center-to-center distance between the two first terminal portions T1 and T1 disposed on both sides in the width direction of the second terminal portion T2 is set to 30 mm, this value is an example, and the value is particularly limited Absent. The thickness of the first electrode 21 is in the range of about 110 nm to 300 nm, the thickness of the organic EL layer 22 is in the range of about 150 nm to 300 nm, the thickness of the second electrode 23 is in the range of about 70 nm to 300 nm The thickness of each of the auxiliary electrode 26, the first metal film 27 and the second metal film 28 is appropriately set in the range of about 300 nm to 600 nm. There is no particular limitation.

Further, with regard to the width of the auxiliary electrode 26, the wider the width, the lower the impedance of the auxiliary electrode 26, and the in-plane variation of the luminance of the light emitting unit 20 is reduced. Since it decreases, it is preferable to set in the range of about 0.3 mm to 3 mm. In a luminaire in which a plurality of planar light emitting devices A according to the present embodiment are arranged as a light source, as the width of the auxiliary electrode 26 is narrowed, the distance between the adjacent light emitting units 20 can be reduced and the appearance becomes better. In addition, although the distance between the first terminal portion T1 and the second terminal portion T2 and the peripheral edge of the translucent substrate 1 is set to 0.2 mm, this value is not particularly limited. It is preferable to set appropriately in the range of about 1 to 2 mm. In order to reduce the area of the non-light emitting portion of the planar light emitting device A, it is preferable to shorten the distance between the first terminal portion T1 and the second terminal portion T2 and the peripheral edge of the translucent substrate 1. When it is necessary to secure a predetermined creepage distance between the portion T1 and the second terminal portion T2 and another metal member (for example, a metal fixture body of a lighting fixture), the creepage distance is longer than the creepage distance. It is preferable to set it to a value.

By the way, in the example of FIG. 1, the width dimension (length in the second direction) of the lead wire 23b formed of metal such as aluminum or silver is set to a value slightly smaller than the width dimension of the second terminal portion T2. However, if a current of critical current density (1 × 10 ⁵ A / cm ² when metal is aluminum) flows for a long time in the lead wire 23 b of the lead wire 23 b, electromigration occurs and disconnection easily occurs. There is a concern that On the other hand, the first layer 24 formed of TCO such as ITO and continued to the first electrode 21 has a large critical current density and a large margin with respect to the critical current density as compared with the lead-out wiring 23b.

Therefore, the inventors of the present invention improve the electromigration resistance (hereinafter abbreviated as EM resistance) by making the total dimension of the width of the second terminal portion T2 larger than the total dimension of the width of the first terminal portion T1. I thought about that. Referring to FIG. 1, the total dimension of the widths of the second terminal portions T2 is the total dimension of the widths of the four second terminal portions T2 (the widths of all the second terminal portions T2 in the second direction). The total dimension of the widths of the first terminal portions T1 is the total dimension of the widths of the six first terminal portions T1 (the widths of all the first terminal portions T1 in the second direction).

The sum of the total dimension of the width of the first terminal portion T1 and the total dimension of the second terminal portion T2 is a constant value, and the total dimension of the width of the first terminal portion T1 is the total dimension of the width of the second terminal portion T2. FIG. 10 shows the results of simulating the brightness uniformity and the drive voltage under the conditions of each terminal width ratio by variously changing the terminal width ratio which is the value divided by. In FIG. 10, the horizontal axis represents the terminal width ratio, the vertical axis on the left is the luminance uniformity, and the vertical axis on the right is the drive voltage. Further, in FIG. 10, A1 is a simulation result of the luminance uniformity, and A2 is a simulation result of the drive voltage. Here, when the total dimension of the width of the first terminal portion T1 and the total dimension of the width of the second terminal portion T2 have the same value, the terminal width ratio is 0.5. On the other hand, when the total dimension of the width of the second terminal portion T2 is larger than the total dimension of the width of the first terminal portion T1, the terminal width ratio becomes smaller than 0.5. Conversely, when the total dimension of the width of the second terminal portion T2 is smaller than the total dimension of the width of the first terminal portion T1, the terminal width ratio becomes larger than 0.5.

In the above simulation, the first electrode 21, the first layer 24, and the second layer 25 are made of an ITO film having a thickness of 150 nm, the thickness of the organic EL layer 22 is made 150 nm, and the second electrode 23 and the lead wire 23b are provided. The planar size of the light emitting unit 20 is 80 mm square, and the distance between the centers of two first terminal portions T1 and T1 disposed on both sides in the width direction of the second terminal portion T2 is 30 mm. The current supplied to the organic EL element 2 was 275 mA. Further, in the simulation, using the value of the sheet resistance of each component of the organic EL element 2 and the voltage-current characteristics of the organic EL layer 22, the voltage at the first electrode 21, the second electrode 23 and the auxiliary electrode 26 The distribution and the current density distribution of the current flowing in the thickness direction of the organic EL layer 22 are calculated. Also, the luminance uniformity is a percentage of the lowest current density to the highest current density in the current density distribution.

From FIG. 10, it can be seen that the luminance uniformity is substantially constant even if the terminal width ratio is changed in the range of 0.25 to 0.83. Further, from FIG. 10, when the terminal width ratio is changed in the range of 0.25 to 0.83, the drive voltage is lowest when the terminal width ratio is 0.5, and the terminal width ratio is more than 0.5. It can be seen that the drive voltage tends to become higher as it becomes larger, and the drive voltage tends to become higher as the terminal width ratio becomes smaller than 0.5. However, even if the terminal width ratio is smaller than 0.5, if the terminal width ratio is 0.33 or more, it is found that the driving voltage is substantially the same as the case where the terminal width ratio is 0.5. I got In short, in the basic configuration of the planar light emitting device A described above, the case where the terminal width ratio is 0.5 is the lowest power consumption, but if the terminal width ratio is 0.33 or more, the terminal width ratio is 0. It is possible to achieve the same level of power consumption as in the case of 5. As in the case where the terminal width ratio is 0.5, it is possible to achieve energy saving by lowering the drive voltage.

Therefore, in the planar light emitting device A of the present embodiment, a value obtained by dividing the total dimension of the width of the first terminal portion T1 by the total dimension of the width of the second terminal portion T2 (hereinafter referred to as "set value") is 0.33. It is made to set by more than 0.67. The set value is preferably 0.33 or more and 0.6 or less, and more preferably 0.33 or more and less than 0.5.

In the planar light emitting device A according to the present embodiment described above, the drive voltage increases because the set value is 0.33 or more and 0.67 or less (desirably 0.6 or less, more preferably less than 0.5). It is possible to improve the reliability by improving the EM resistance while suppressing the In the planar light emitting device A, the luminance is substantially proportional to the value of the current flowing through the organic EL element 2. Therefore, when driving with a constant current, the lower the drive voltage, the higher the power efficiency, and the lower the power consumption. It is possible to

Further, regarding the planar light emitting device A, the total number of the first terminal portions T1 and the second terminal portions T2 disposed along each of the two sides of the light emitting unit 20 with the terminal width ratio being 0.5 (terminals Table 1 shows the results of simulating the drive voltage and the brightness uniformity when the number is varied. In this simulation, the first electrode 21, the first layer 24, and the second layer 25 are made of an ITO film having a thickness of 150 nm, the thickness of the organic EL layer 22 is 150 nm, and the second electrode 23 and the lead wire 23b are thick. An Al film of 80 nm was used, the planar size of the light emitting unit 20 was 80 mm, and the current flow to the organic EL element 2 was 275 mA. In the example shown in FIG. 1, the number of terminals is five. Further, in the simulation, using the value of the sheet resistance of each component of the organic EL element 2 and the voltage-current characteristics of the organic EL layer 22, the voltage at the first electrode 21, the second electrode 23 and the auxiliary electrode 26 The distribution and the current density distribution of the current flowing in the thickness direction of the organic EL layer 22 are calculated. Also, the luminance uniformity is a percentage of the lowest current density to the highest current density in the current density distribution.

From Table 1, it can be seen that when the number of terminals is an odd number of 5 or more, the drive voltage is substantially constant, and the luminance uniformity is high and substantially constant as compared to the case of three terminals. Therefore, the m second terminal portions T2 and the [m + 1] first terminal portions T1 have a width of the second terminal portion T2 along each of two predetermined parallel sides of the light emitting unit 20 having a rectangular quadrilateral shape. In the planar light emitting device A of this embodiment disposed so that the first terminal portions T1 are positioned on both sides of the direction, it is sufficient that m よい 1, but by m 、 2, the case of m = 1 In comparison with the above, it is possible to improve the brightness uniformity. Even when the terminal width ratio is 0.67 or less (desirably 0.6 or less, more preferably less than 0.5), the drive voltage is substantially constant if the number of terminals is an odd number of 5 or more as in Table 1. The brightness uniformity is high and substantially constant as compared to the case of three terminals. However, as the number of terminals increases, the number of connection points with metal wires (bonding wires) and the like increases, so from the viewpoint of the number of connection points, it is preferable to reduce the number of terminals. Therefore, in the planar light emitting device A of the present embodiment, the number of terminals is preferably five.

By the way, the plan view shape of the light-transmissive substrate 1 may be a right-angled quadrilateral shape, and is not limited to a rectangular shape, and may be a square shape in which two sides are along the first direction. If the shape is a rectangular shape extending in the second direction, two long sides in the light emitting unit 20 correspond to two parallel sides of the light emitting unit 20 in the second direction described above. Further, the planar view shape of the translucent substrate 1 is a rectangular shape in which two long sides are in the first direction, and the planar view shape of the light emitting unit 20 is not similar to the translucent substrate 1 and the two long sides are In the rectangular shape along the second direction, two long sides in the light emitting unit 20 correspond to two parallel sides of the light emitting unit 20 in the second direction described above.

In the organic EL element 2 described above, the first electrode 21 made of a transparent conductive film constitutes an anode, and the second electrode 23 whose sheet resistance is smaller than that of the first electrode 21 constitutes a cathode. May constitute a cathode and the second electrode 23 may constitute an anode, in any case, as long as it is possible to extract light through the first electrode 21 made of a transparent conductive film.

Moreover, although the planar light-emitting device A demonstrated by embodiment can be used suitably as a light source for illumination, for example, it is possible not only for illumination but to use for another use.

Although the present invention has been described with reference to several preferred embodiments, various modifications and variations can be made by those skilled in the art without departing from the true spirit and scope of the present invention, ie, the claims.

Claims

A translucent substrate,
A planar light emitting device comprising: an organic EL element formed on one surface side of the translucent substrate;
The organic EL element is
A first electrode disposed on the one surface side of the translucent substrate and made of a transparent conductive film;
A light emitting layer which is disposed on the side opposite to the light transmitting substrate side of the first electrode and made of an organic material;
A second electrode formed of a metal film and disposed on the side opposite to the first electrode side in the light emitting layer;
A plurality of first terminal portions disposed on the side of the light emitting portion where the first electrode, the light emitting layer, and the second electrode overlap, and electrically connected to the first electrode;
A plurality of second terminal portions disposed laterally of the light emitting portion and electrically connected to the second electrode;
An auxiliary formed of a material having a smaller specific resistance than the first electrode and formed in the vicinity of a peripheral portion of the surface of the first electrode opposite to the light transmitting substrate side and electrically connected to the first electrode Equipped with electrodes,
The plan view shape of the light emitting unit is a right quadrilateral shape,
The m second terminals and [m + 1] first terminals along each of two predetermined parallel sides of the light emitting section having the right-angled quadrilateral shape are disposed on both sides in the width direction of the second terminals. Are arranged so that the first terminal portion is located, where m is an integer of 1 or more,
Each of the first terminal portion and the second terminal portion has a laminated structure of a transparent conductive oxide layer and a metal layer,
A value obtained by dividing the total dimension of the width of the first terminal portion by the total dimension of the width of the second terminal portion is 0.33 or more and 0.67 or less.
The planar light emitting device according to claim 1, wherein a value obtained by dividing the total dimension of the width of the first terminal portion by the total dimension of the width of the second terminal portion is 0.33 or more and less than 0.5. .
3. The planar light emission according to claim 1, wherein the organic EL element further comprises an insulating film covering side edges of the auxiliary electrode and the first electrode on the one surface side of the translucent substrate. apparatus.
The planar light emitting device according to any one of claims 1 to 3, wherein m m2.