JP2007073305A - Organic el light emitting device and manufacturing method of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic EL light emitting device provided with an auxiliary electrode of a transparent electrode having an inter-layer insulation layer formed on the supporting electrode with high quality, with reduced unevenness of brightness. <P>SOLUTION: The auxiliary electrode 12 having a prescribed pattern, a first electrode take-out wiring 13 and a second electrode take-out wiring 14, and a transparent electrode 15 covering a part of the first electrode take-out wiring 13 and the second electrode take-out wiring 14 are arranged on a transparent glass substrate 11, The inter-layer insulating layer 16 is formed on the upper part of the auxiliary electrode 12 through the transparent electrode 15, and the organic EL layer 17 is laminated on the the transparent electrode 15. An opposing electrode 18 is formed on the organic EL layer 17 and the inter-layer insulating layer in opposition to the transparent electrode 15, and the opposing electrode 18 is connected to the second electrode take-out wiring 14. Furthermore, whole part is airtightly sealed by a sealing can 19. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an organic EL light-emitting device and a method for manufacturing the same, and more specifically, an organic EL layer containing an organic light-emitting material is sandwiched between a transparent electrode and a counter electrode to assist in reducing the resistance of the transparent electrode. The present invention relates to an organic EL light emitting device provided with an electrode and a method for manufacturing the same.

  In recent years, by utilizing the electroluminescence (EL) phenomenon of an organic thin film, an organic EL layer containing an organic light emitting layer is sandwiched between a pair of electrodes, and a voltage is applied between the electrodes to pass a current through the organic EL layer. Various studies for practical application of organic EL elements that emit light have been energetically advanced. This organic EL element is a self-luminous element suitable for a display device such as an FPD (flat panel display), a surface light source backlight of a liquid crystal display device composed of non-self-luminous elements, or an illuminating device such as an illumination lamp. Hereinafter, the display device and the illumination device using the organic EL element are collectively referred to as an organic EL light emitting device.

  In the organic EL light emitting device, a transparent electrode made of a translucent material such as ITO (indium tin oxide) or ZnO (zinc oxide) is essential. However, in general, the conductivity of the transparent electrode is not sufficiently large. For this reason, the difference in the resistance value of the current path increases between the portion near and far from the power source of the light emitting device, and the difference also increases in the current value of the organic EL layer. Since the light emission luminance of the organic EL layer strongly depends on the current value, the luminance unevenness of the light emission tends to occur in the organic EL light emitting device. Therefore, various methods have been proposed as a method for reducing the luminance unevenness, in which a low-resistance auxiliary electrode is electrically connected to the transparent electrode (see, for example, Patent Document 1).

  A conventional organic EL light emitting device having the auxiliary electrode will be described with reference to FIGS. FIG. 7 is a cross-sectional view of a conventional organic EL light-emitting device, and FIG. 8 is a cross-sectional view for each process showing the manufacturing method.

  As shown in FIG. 7, in the organic EL light emitting device 100, for example, a transparent electrode 102 is formed on a transparent glass substrate 101. The auxiliary electrode 103 having a predetermined pattern is disposed on the transparent electrode 102 by a metal material having a resistivity lower than that of the transparent electrode 102. Further, an interlayer insulating layer 104 is provided so as to cover the auxiliary electrode 103, and an organic EL layer 105 containing an organic light emitting material is laminated on the transparent electrode 102. A counter electrode 106 is provided on the organic EL layer 105 so as to face the transparent electrode 102, and the transparent electrode 102 is connected to a power source through a first electrode lead-out wiring 107. Similarly, the counter electrode 106 is connected to another power source through the second electrode extraction wiring 108. The whole is hermetically sealed by a sealing can 109.

In the organic EL light emitting device 100, the transparent electrode 102, the organic EL layer 105, and the counter electrode 106 constitute an organic EL element. Here, the auxiliary electrode 103 has a smaller resistivity than the transparent electrode 102 but does not transmit visible light. Therefore, a structure in which the interlayer insulating layer 104 is provided so as to cover the auxiliary electrode 103 is provided, and a region where the auxiliary electrode 103 is provided is a non-light emitting region where no organic light emission occurs.
Further, the organic EL element of the organic EL light emitting device 100 is particularly susceptible to deterioration due to oxygen or moisture. Therefore, the sealing can 109 is hermetically sealed. Although not shown, a desiccant such as barium oxide powder is enclosed in the sealing can 109 so as to adsorb oxygen gas or moisture.

  In the method of manufacturing the organic EL light emitting device 100, after the transparent glass substrate 101 is washed, a transparent electrode film having a large work function (for example, 4 eV or more) such as an ITO film is vacuum deposited on the surface of the transparent glass substrate 101. The film is formed by a method or a sputtering method. Then, the transparent electrode 102 is formed by patterning into a predetermined shape (FIG. 8A).

  Next, a low-resistance metal film having a low resistivity such as aluminum (Al) is formed by sputtering, and the low-resistance metal film is processed by known photolithography and wet etching. In this manner, the auxiliary electrode 103 is disposed in a predetermined region on the transparent electrode 102, and the first electrode extraction wiring 107 and the second electrode extraction wiring 108 are formed (FIG. 8B). Here, the auxiliary electrode 103 has a visible light non-transmission property.

  Next, for example, a positive photosensitive polyimide film is formed on the entire surface by spin coating, and exposure and development are performed to cover the interlayer insulating layer 104 made of the polyimide film on the wiring of the auxiliary electrode 103 (FIG. 8C). ).

  Next, the organic EL layer 105 is formed on the transparent electrode 102 by a vacuum deposition method using a metal mask for organic film formation (FIG. 8D). Here, the organic EL layer 105 is, for example, 4,4′-bis [N- (2-naphthyl) -N-phenyl-amino] biphenyl (hereinafter abbreviated as α-NPD) which is a hole transport layer, It is an organic thin film formed by laminating a tris (8-quinolinolato) aluminum complex (hereinafter abbreviated as Alq3) which is an organic light emitting layer. Alternatively, the organic EL layer 105 may be a single layer including only an organic light emitting layer, or one layer of a hole injection layer, a hole transport layer, a hole blocking layer, an electron injection layer, an electron transport layer, and an electron blocking layer. A multilayer structure in which the above and the organic light emitting layer are stacked may be used.

  Next, the counter electrode 106 that covers the organic EL layer 105 and the interlayer insulating layer 104 and is electrically connected to the second electrode lead-out wiring 108 is formed by a sputtering method using a metal mask for forming a metal film (FIG. 8). (E)). Here, the counter electrode 106 is formed by sputtering a metal having a small work function (for example, 4 eV or less) such as lithium fluoride (LiF) or Al.

After this, the whole is hermetically sealed with a glass or stainless steel sealing can 109 as shown in FIG. In this hermetic sealing, a UV curable adhesive is applied to the edge of the sealing can 109. And the edge part of the sealing can 109 is joined to the surface of the transparent glass substrate 101 or the surface of the 1st electrode extraction wiring 107 and the 2nd electrode extraction wiring 108 through the said adhesive agent. Although not shown, a desiccant such as barium oxide powder is sealed in the sealing can 109 so that oxygen gas or moisture is adsorbed.
JP 2004-349138 A

However, the conventional organic EL light emitting device has a problem that it is difficult to form a high-quality interlayer insulating layer with high reliability between the auxiliary electrode 103 and the counter electrode 106 formed on the transparent electrode 102. . This is because it is difficult to obtain sufficient adhesion between the interlayer insulating layer 104 such as the photosensitive polyimide film and the auxiliary electrode 103. Furthermore, this is because pinholes are easily formed in the photosensitive polyimide film of the interlayer insulating layer 104 at the step portion of the auxiliary electrode 103. Here, if the film forming conditions of the photosensitive polyimide film are poor, a part of the interlayer insulating layer 104 may be peeled off in the development process after the exposure. For this reason, it has been difficult to improve the manufacturing yield of the organic EL light emitting device.
On the other hand, an effective interlayer insulating film replacing the photosensitive polyimide film has not been found at present. This is because even if an inorganic insulating film such as a high-quality silicon oxide film is applied to the interlayer insulating layer 104, it is difficult to selectively form the insulating film on the auxiliary electrode 103. When such an inorganic insulating film is used, the selective wet etching is essential, but the inorganic insulating film cannot be etched without damaging the transparent electrode 102 or the transparent glass substrate 101.

  Further, the organic EL light emitting device has a problem that the counter electrode 106 formed to cover the interlayer insulating layer 104 is likely to be disconnected at the step portion of the auxiliary electrode 103. This is because in the sputtering of a metal material having a low work function, the metal film deposited on the stepped portion tends to be extremely thin. This is also a factor that makes it difficult to improve the manufacturing yield of the organic EL light emitting device.

  Further, since the region where the auxiliary electrode 103 is disposed does not transmit visible light, the auxiliary electrode 103 cannot be freely disposed on the transparent electrode 102, and when it is disposed as a wiring thereof. There was a problem that many restrictions occurred. For this reason, there are many cases where the luminance unevenness in the organic EL light emitting device using the auxiliary electrode is insufficiently solved.

  The present invention has been made in view of the above circumstances, and in an organic EL light emitting device having an auxiliary electrode of a transparent electrode, the interlayer insulating layer formed on the upper area of the auxiliary electrode is of high quality. Thus, an object of the present invention is to provide an organic EL light-emitting device that has a high manufacturing yield and a low luminance unevenness.

  In order to achieve the above object, the organic EL light-emitting device of the present invention is an organic EL light-emitting device in which at least an organic light-emitting layer is sandwiched between a pair of opposed electrodes on a transparent substrate and light is emitted from the transparent substrate side. The auxiliary electrode disposed on the surface of the transparent substrate, the transparent electrode formed by covering the auxiliary electrode and electrically connecting to the auxiliary electrode as one electrode of the pair of electrodes, and the auxiliary An interlayer insulating layer formed on the upper part of the electrode via the transparent electrode; and a counter electrode disposed as opposed to the transparent electrode so as to cover the interlayer insulating layer as the other electrode of the pair of electrodes. It is configured.

  Since the adhesion between the upper transparent electrode and the interlayer insulating layer becomes very high, a high-quality interlayer insulating layer is provided on the transparent electrode in the upper region of the auxiliary electrode so as to be sandwiched between the counter electrode by the above invention. Become. Thus, an organic EL light emitting device having high reliability and high manufacturing yield is realized.

  In a preferred aspect of the invention, the auxiliary electrode is made of a material having a lower resistivity than the transparent electrode. Alternatively, the auxiliary electrode is embedded in an insulating film formed on the surface of the transparent substrate. Alternatively, the auxiliary electrode is embedded in a recess formed on the surface of the transparent substrate.

  According to the above invention, the underlying step of the interlayer insulating film is greatly reduced. For this reason, pinholes in the stepped portion of the interlayer insulating layer are eliminated, the electrical insulating property of the interlayer insulating layer is extremely excellent, and an organic EL light emitting device having high reliability and a high manufacturing yield is realized.

  And in the suitable one aspect | mode of the said invention, the said recessed part has an inclined surface in the inner wall. Alternatively, in the concave portion, a relational expression of sin θ = 1 / n is satisfied, where θ is an inclination angle of the inclined surface with respect to an axis perpendicular to the surface of the transparent substrate, and n is a refractive index of the transparent substrate. .

  According to the above invention, the light that has been totally reflected on the exit surface of the transparent substrate and has not been emitted to the outside of the transparent substrate is reflected once by the inclined surface and then incident on the exit surface. It can be made below the critical angle of reflection. Then, EL light can be emitted to the outside of the transparent substrate from the inclined surface of the recess in which the auxiliary electrode is embedded. For this reason, conventionally, the influence on the display or illumination of the auxiliary electrode which is a non-light emitting region is extremely small, and the degree of freedom of wiring when the auxiliary electrode is provided increases. In this way, a high-brightness organic EL light-emitting device with high reliability and extremely low brightness unevenness is realized.

  In the above invention, the interlayer insulating layer is made of a photosensitive insulating film. A suitable photosensitive insulating film is a photosensitive polyimide film.

  And the manufacturing method of the organic electroluminescent light-emitting device of this invention is a manufacturing method of the organic electroluminescent light-emitting device which emits light from the said transparent substrate side at least an organic light emitting layer is pinched between a pair of opposing electrodes on a transparent substrate. A step of forming an auxiliary electrode on the surface of the transparent substrate, a step of forming a transparent electrode that covers the auxiliary electrode and is electrically connected to the auxiliary electrode as one electrode of the pair of electrodes, and the transparent Forming a photosensitive insulating film on the electrode, exposing and developing the photosensitive insulating film to form an interlayer insulating layer on the auxiliary electrode via the transparent electrode, and as the other electrode of the pair of electrodes And a step of forming a counter electrode that covers the interlayer insulating layer and is disposed to face the transparent electrode.

  Alternatively, the organic EL light emitting device manufacturing method of the present invention is a method for manufacturing an organic EL light emitting device in which at least an organic light emitting layer is sandwiched between a pair of opposed electrodes on a transparent substrate and light is emitted from the transparent substrate side. A step of forming an aluminum film on the surface of the transparent substrate; a step of selectively anodizing the aluminum film to form an auxiliary electrode; and covering the auxiliary electrode as one electrode of the pair of electrodes Forming a transparent electrode electrically connected to the surface of the auxiliary electrode; forming a photosensitive insulating film on the transparent electrode; and exposing and developing the photosensitive insulating film to form the transparent electrode on the auxiliary electrode. A step of forming an interlayer insulating layer through the substrate, and a step of forming a counter electrode that covers the interlayer insulating layer and is disposed opposite to the transparent electrode as the other electrode of the pair of electrodes. You have me.

  Alternatively, the organic EL light emitting device manufacturing method of the present invention is a method for manufacturing an organic EL light emitting device in which at least an organic light emitting layer is sandwiched between a pair of opposed electrodes on a transparent substrate and light is emitted from the transparent substrate side. A step of forming a recess in the surface of the transparent substrate; a step of forming an auxiliary electrode so as to be embedded in the recess; and a surface of the auxiliary electrode and the transparent substrate as one electrode of the pair of electrodes Forming a transparent electrode that is electrically connected to the auxiliary electrode, forming a photosensitive insulating film on the transparent electrode, exposing and developing the photosensitive insulating film, and forming the transparent electrode on the auxiliary electrode. A step of forming an interlayer insulating layer through the substrate, and a step of forming a counter electrode that covers the interlayer insulating layer and is disposed opposite to the transparent electrode as the other electrode of the pair of electrodes. You have me.

  According to the configuration of the present invention, in an organic EL light emitting device provided with an auxiliary electrode of a transparent electrode, the interlayer insulating layer formed on the upper area of the auxiliary electrode is of high quality, has a high manufacturing yield, and has uneven luminance. It is possible to provide an organic EL light-emitting device in which the size is reduced.

Several preferred embodiments of the present invention will be described below with reference to the drawings. In this drawing, the same or similar parts are denoted by common reference numerals.
(Embodiment 1)
A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view of a preferred organic EL light-emitting device of the present embodiment, and FIG. 2 is a cross-sectional view by process showing the manufacturing method.

As shown in FIG. 1, in the organic EL light emitting device 10, for example, an auxiliary electrode 12 having a predetermined pattern is disposed on a transparent glass substrate 11. Similarly, a first electrode extraction wiring 13 and a second electrode extraction wiring 14 are formed. Then, a transparent electrode 15 that covers and electrically connects part of the auxiliary electrode 12 and the first electrode lead-out wiring 13 is formed. Here, the transparent electrode 15 is a transparent electrode made of a light-transmitting material such as ITO, and the auxiliary electrode 12 is made of Al having a resistivity lower than that of the transparent electrode.
Further, an interlayer insulating layer 16 is provided on the auxiliary electrode 12 via a transparent electrode 15, and an organic EL layer 17 is laminated on the transparent electrode 15. A counter electrode 18 is provided on the organic EL layer 17 and the interlayer insulating layer 16 so as to face the transparent electrode 15. Here, the transparent electrode 15 is connected to a power source through the first electrode lead-out wiring 13. Similarly, the counter electrode 18 is connected to another power source through the second electrode lead-out wiring 14. The whole is hermetically sealed by a sealing can 19.

In the organic EL light emitting device 10, the transparent electrode 15, the organic EL layer 17, and the counter electrode 18 constitute an organic EL element. Even in this case, the auxiliary electrode 12 is a non-translucent electrode that has a lower resistivity than the transparent electrode 15 but does not transmit visible light. In view of this, the interlayer insulating layer 16 is provided on the auxiliary electrode 12 via the transparent electrode 15, and the area where the auxiliary electrode 12 is disposed is a non-light emitting area where no organic light emission occurs.
Further, as described in the prior art, since the organic EL element of the organic EL light emitting device 10 is easily deteriorated by oxygen or moisture, the organic EL element is hermetically sealed by the sealing can 19. ing. And the said transparent glass substrate 11 and the sealing can 19 are comprised with the material which has non-moisture permeability. Although not shown, a desiccant such as barium oxide powder is enclosed in the sealing can 19 so as to adsorb oxygen gas or moisture.

  In the method for manufacturing the organic EL light emitting device 10, after the transparent glass substrate 11 is washed, a low resistance metal film such as Al is formed by sputtering. Then, the low resistance metal film is processed into a predetermined pattern by known photolithography and wet etching. In this way, as shown in FIG. 2A, the auxiliary electrode 13 having a predetermined pattern is arranged in a wiring pattern on the transparent glass substrate 11, and the first electrode extraction wiring 13 and the second electrode extraction wiring are arranged. 14 is formed.

  Next, a translucent material having a large work function such as an ITO film is applied by vacuum deposition or sputtering so as to cover the auxiliary electrode 12, the first electrode extraction wiring 13, and the second electrode extraction wiring 14. Etc. are formed. Then, the transparent electrode 15 is formed by patterning into a predetermined shape as shown in FIG. Here, the transparent electrode 15 is electrically connected to the auxiliary electrode 12 and the first electrode lead-out wiring 13.

  Next, for example, a positive photosensitive polyimide film is formed on the entire surface by spin coating, and the exposure and development are performed. In this way, as shown in FIG. 2C, the interlayer insulating layer 16 made of the polyimide film is provided on the transparent electrode 15 in the region above the auxiliary electrode 12.

  Next, as shown in FIG. 2D, an organic EL layer 17 is formed on the transparent electrode 15 by a vacuum deposition method using a metal mask for organic film formation. Here, as described in the prior art, the organic EL layer 17 is, for example, an organic thin film in which α-NPD and Alq3 are stacked. Alternatively, the organic EL layer 17 may be a single layer including only an organic light emitting layer. The organic EL layer has a multilayer structure in which one or more of a hole injection layer, a hole transport layer, a hole blocking layer, an electron injection layer, an electron transport layer, and an electron blocking layer and an organic light emitting layer are stacked. May be.

  Next, as shown in FIG. 2E, the organic EL layer 17 and the interlayer insulating layer 16 are covered by a sputtering method using a metal mask for forming a metal film, and electrically connected to the second electrode lead-out wiring 14. The counter electrode 18 is formed. Here, a metal material having a small work function is used as the counter electrode 18 so as to facilitate electron injection into the organic EL layer 17. Furthermore, any metal material that reflects visible light emitted from the organic light emitting layer toward the transparent glass substrate 11 is suitable. Examples of such a metal material include LiF and Al described above.

  After this, as described in the prior art, the whole is hermetically sealed with a non-moisture permeable glass or stainless steel sealing can 19 as shown in FIG. In this hermetic sealing step, a UV curable adhesive is applied to the edge of the sealing can 19, and the surface of the transparent glass substrate 11, the first electrode extraction wiring 13, and the second electrode extraction wiring 14. And stick together. Then, the adhesive is UV cured so that UV light does not irradiate the organic EL layer 17. In this manner, the sealing can 19 is bonded to the transparent glass substrate 11 through the adhesive. Although not shown, a desiccant such as barium oxide powder is sealed in the sealing can 19 so that oxygen gas or moisture is adsorbed.

  In the organic EL light emitting device according to the first embodiment, the interlayer insulating layer 16 is formed on the auxiliary electrode 12 via the transparent electrode 15. Here, the adhesion between the transparent electrode 15 and the interlayer insulating layer 16 such as a polyimide film is very high. For this reason, a high-quality interlayer insulating layer is provided on the transparent electrode 15 in the region above the auxiliary electrode 15 so as to be sandwiched between the counter electrode 18. In this way, an organic EL light emitting device having high reliability and high manufacturing yield is realized.

(Embodiment 2)
Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a cross-sectional view of a preferred organic EL light emitting device of the present embodiment, and FIGS. 4 and 5 are cross-sectional views by process showing the manufacturing method. The present embodiment is characterized in that the level difference caused by the auxiliary electrode 12 described in the first embodiment is reduced.

As shown in FIG. 3, in the organic EL light emitting device 10 a of this embodiment, on the transparent glass substrate 11, a wiring-like auxiliary electrode 12 formed in a predetermined pattern, a first electrode extraction wiring 13, and a second electrode extraction. The wiring 14 is provided so as to be embedded in a predetermined region of the insulating film 20. In this manner, the upper part of the auxiliary electrode 12 and the upper parts of the first electrode extraction wiring 13 and the second electrode extraction wiring 14 are flattened. Then, a transparent electrode 15 that covers and electrically connects the flattened auxiliary electrode 12 and the first electrode lead-out wiring 13 is formed. Here, the transparent electrode 15 is a transparent electrode, and the auxiliary electrode 12 is made of, for example, Al having a resistivity lower than that of the transparent electrode.
An interlayer insulating layer 16 a is provided on the flattened auxiliary electrode 13 via a transparent electrode 15, and an organic EL layer 17 is laminated on the transparent electrode 15. Further, a counter electrode 18 is provided on the organic EL layer 17 and the interlayer insulating layer 16 a so as to face the transparent electrode 15. Here, the transparent electrode 15 is connected to a power source through the first electrode lead-out wiring 13, and the counter electrode 18 is connected to another power source through the second electrode lead-out wiring 14. The whole is hermetically sealed by a sealing can 19. Others are the same as those described in the first embodiment, and a description thereof will be omitted.

  Next, a method for manufacturing the organic EL light emitting device 10a will be described. First, as shown in FIG. 4A, after the transparent glass substrate 11 is washed, an aluminum film 21 is formed by a sputtering method.

  Next, as shown in FIG. 4B, a resist mask 22 having a predetermined pattern is formed by known photolithography. Then, using the resist mask 22 as an anodic oxidation mask, the aluminum film 21 is subjected to an electrochemical reaction in, for example, an oxalic acid electrolytic solution or a boric acid electrolytic solution. By this electrochemical reaction, as shown in FIG. 4C, the aluminum film 21 in the region without the resist mask 22 is selectively anodized from its surface to become an alumina film, which is modified into the insulating film 20. Here, usually, the alumina film has porosity. Therefore, the alumina film is subsequently inactivated through a sealing process by a chemical method at room temperature.

  Next, the resist mask 22 is removed with a known organic chemical solution. Thus, as shown in FIG. 4D, the auxiliary electrode 12, the first electrode lead-out wiring 13, and the second electrode lead-out wiring 14 are formed so as to be embedded in the insulating film 20. Here, the surface of the insulating film 20 and the surfaces of the auxiliary electrode 12, the first electrode lead-out wiring 13, and the second electrode lead-out wiring 14 are flattened on substantially the same plane.

  Next, as shown in FIG. 5A, the metal component is formed so as to cover the auxiliary electrode 12, the part of the first electrode lead-out wiring 13, and the insulating film 20 embedded in the insulating film 20 and planarized. The transparent electrode 15 is formed by the sputtering method of the transparent electrode material using the metal mask for film. The transparent electrode 15 is electrically connected to the auxiliary electrode 12 and the first electrode lead-out wiring 13.

  Next, for example, a positive photosensitive polyimide film is formed on the entire surface by spin coating, and the exposure and development are performed. In this manner, as shown in FIG. 5B, the interlayer insulating layer 16a made of the polyimide film is provided on the transparent electrode 15 in the region above the auxiliary electrode 12. Here, as described above, since the transparent electrode 15 is formed on a flat base without a step, there is no pinhole in the interlayer insulating layer 16a, and the insulation is extremely excellent.

  The subsequent steps are the same as those in the first embodiment. That is, as shown in FIG. 5C, the organic EL layer 17 is formed on the transparent electrode 15 by a vacuum deposition method using a metal mask for organic film formation. Then, as shown in FIG. 5D, the organic EL layer 17 and the interlayer insulating layer 16a are covered by a sputtering method using a metal mask for forming a metal film, and are electrically connected to the second electrode lead-out wiring 14. The counter electrode 18 is formed. Then, the whole is hermetically sealed with a non-moisture permeable glass or stainless steel sealing can 19 as shown in FIG.

  In the organic EL light emitting device according to the second embodiment, the auxiliary electrode 12 is disposed so as to be embedded in the insulating film 20. The interlayer insulating layer 16a is formed on the transparent electrode 15 in the region above the flattened auxiliary electrode 12. For this reason, as in the case of the first embodiment, the adhesion between the transparent electrode 15 and the interlayer insulating layer 16a such as a polyimide film becomes very high. Further, the underlying step of the interlayer insulating film 16a is greatly reduced. For this reason, the pinhole in the step part of the interlayer insulation layer 16a is eliminated. In this way, the electrical insulation of the interlayer insulating layer 16a becomes extremely excellent, and an organic EL light emitting device having high reliability and high manufacturing yield is realized.

  In the second embodiment, the auxiliary electrode 12 may be formed so as to be embedded in the insulating film 20 by a so-called damascene wiring formation method. In this method, the insulating film 20 is deposited on the transparent glass substrate 11, the insulating film is selectively etched to form a groove with a predetermined pattern, and a metal (for example, Cu, Al) is embedded in the groove. . Here, the filling of the metal can be easily performed by forming the metal film on the insulating film in which the groove is formed and polishing and removing the metal film on the insulating film by chemical mechanical polishing. .

(Embodiment 3)
Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 6 is a partial cross-sectional view of the organic EL light emitting device of this embodiment. The present embodiment is characterized in that the level difference due to the auxiliary electrode 12 described in the first embodiment is reduced, and the influence on the display or illumination of the auxiliary electrode 12 serving as a non-light emitting region is reduced.

As shown in FIG. 6, in the organic EL light emitting device 10b of the present embodiment, a groove 23 is formed on the surface portion of the transparent glass substrate 11 along the wiring pattern of the auxiliary electrode 12a. A metal material such as Al having a lower resistivity than the transparent electrode 15 is buried in the groove 23 to form the auxiliary electrode 12a. A transparent electrode 15 that covers the auxiliary electrode 12a formed so as to be embedded in the groove 23 and is electrically connected to the upper portion of the auxiliary electrode 12a is formed. Here, although not shown, the transparent electrode 15 is electrically connected to the first electrode lead-out wiring 13 as in the case of the first embodiment.
In the same manner as in the second embodiment, an interlayer insulating layer 16a is provided on the flattened auxiliary electrode 13 via a transparent electrode 15, and an organic EL layer 17 is laminated on the transparent electrode 15. Formed. Further, a counter electrode 18 which is a counter electrode of the transparent electrode 15 is provided on the organic EL layer 17 and the interlayer insulating layer 16a. Here, the transparent electrode 15 is connected to a power source through the first electrode lead-out wiring 13, and the counter electrode 18 is connected to another power source through the second electrode lead-out wiring 14 (not shown). The rest is hermetically sealed by the sealing can 19 and is the same as that described in the first embodiment.

  As shown in FIG. 6, the inner wall of the groove 23 has an inclined surface, and the inclination angle of the inclined surface with respect to an axis perpendicular to the surface of the transparent glass substrate 11 is θ, and θ is sin θ = 1 / n. It is preferable to form the inclined surface so as to satisfy the equation. If it does in this way, the light emitted substantially isotropic from the organic EL layer 17 will inject into the transparent glass substrate 11, and a part will come to reflect on this inclined surface. And it radiate | emits outside in the output surface 11a of the transparent glass substrate 11, and light will radiate | emit also from the auxiliary electrode 12a area | region which is a non-light-emission area | region originally. Here, if there is no reflection on the inclined surface, the light coming to the emission surface 11a of the transparent glass substrate 11 at an angle equal to or greater than the critical angle satisfying the above relational expression is totally reflected and not emitted from the transparent glass substrate 11. Become. In this way, the influence on the illumination of the auxiliary electrode 12a that becomes the non-light emitting region is greatly reduced.

  In FIG. 6, the groove 23 having a V-shaped cross-sectional shape is shown, but the cross-sectional shape of the groove 23 is not limited to such a shape. As described above, any concave portion having an inclined surface that reflects light incident on the transparent glass substrate 11 from the organic thin film 17 and eliminates total reflection on the emission surface 11a of the transparent glass substrate 11 may be used. In FIG. 6, the auxiliary electrode 12 a may be formed so as to be completely embedded in the groove 23.

  In the organic EL light emitting device according to the third embodiment, the auxiliary electrode 12 a is flattened so as to be embedded in the groove 23 formed in the surface portion of the transparent glass substrate 11. The interlayer insulating layer 16a is formed on the transparent electrode 15 in the region above the auxiliary electrode 12a. For this reason, in the same manner as described in the second embodiment, the electrical insulation of the interlayer insulating layer 16a is extremely excellent, and an organic EL light emitting device having high reliability and high manufacturing yield is obtained. Realize.

  Further, conventionally, light that has been totally reflected on the emission surface 11a of the transparent glass substrate 11 and has not been emitted can be emitted to the outside of the transparent glass substrate 11 in the region of the groove 23 in which the auxiliary electrode 12a is embedded. For this reason, the influence on the display or illumination of the auxiliary electrode 12a serving as a non-light-emitting region is extremely reduced, and the degree of freedom of wiring when the auxiliary electrode 12a is provided increases. In this way, a high-brightness organic EL light-emitting device with high reliability and extremely low brightness unevenness is realized.

  As mentioned above, although preferred embodiment of this invention was described, embodiment mentioned above does not limit this invention. Those skilled in the art can make various modifications and changes in specific embodiments without departing from the technical idea and technical scope of the present invention. For example, the auxiliary electrode may be made of an aluminum copper alloy, Cu, or Au in addition to Al, or may be formed thick so as to reduce the resistance of the transparent electrode. In forming the interlayer insulating layer, a photosensitive insulating film may be used in addition to the photosensitive polyimide film, and an interlayer insulating layer may be selectively provided on the auxiliary electrode through the exposure and development processes.

It is sectional drawing which shows the organic electroluminescent light-emitting device concerning Embodiment 1 of this invention. It is sectional drawing according to process which shows the manufacturing method of the organic electroluminescent light emitting device concerning Embodiment 1 of this invention. It is sectional drawing which shows the organic electroluminescent light-emitting device concerning Embodiment 2 of this invention. It is sectional drawing according to process which shows the manufacturing method of the organic electroluminescent light emitting device concerning Embodiment 2 of this invention. FIG. 5 is a cross-sectional view by process following the process illustrated in FIG. 4. It is a partial cross section figure which shows the organic electroluminescent light-emitting device concerning Embodiment 3 of this invention. It is sectional drawing which shows the organic electroluminescent light emitting device concerning a prior art. It is sectional drawing according to process which shows the manufacturing method of the organic electroluminescent light emitting device concerning a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10, 10a, 10b Organic EL light-emitting device 11 Transparent glass substrate 11a Outgoing surface 12, 12a Auxiliary electrode 13 1st electrode extraction wiring 14 2nd electrode extraction wiring 15 Transparent electrode 16, 16a Interlayer insulation layer 17 Organic EL layer 18 Opposite Electrode 19 Sealing can 20 Insulating film 21 Aluminum film 22 Resist mask 23 Groove

Claims (11)

An organic EL light emitting device in which at least an organic light emitting layer is sandwiched between a pair of opposed electrodes on a transparent substrate, and emits light from the transparent substrate side,
An auxiliary electrode disposed on the surface of the transparent substrate;
As one electrode of the pair of electrodes, a transparent electrode formed by covering the auxiliary electrode and electrically connecting to the auxiliary electrode;
An interlayer insulating layer formed on the auxiliary electrode through the transparent electrode;
As the other electrode of the pair of electrodes, a counter electrode that covers the interlayer insulating layer and is disposed to face the transparent electrode;
An organic EL light emitting device comprising:   The organic EL light-emitting device according to claim 1, wherein the auxiliary electrode is made of a material having a resistivity lower than that of the transparent electrode.   The organic EL light-emitting device according to claim 1, wherein the auxiliary electrode is embedded in an insulating film formed on a surface of the transparent substrate.   The organic EL light-emitting device according to claim 1, wherein the auxiliary electrode is embedded and disposed in a recess formed on a surface of the transparent substrate.   The organic EL light-emitting device according to claim 4, wherein the recess has an inclined surface on an inner wall thereof.   The relational expression of sin θ = 1 / n is satisfied, where θ is an inclination angle of the inclined surface with respect to an axis perpendicular to the surface of the transparent substrate, and n is a refractive index of the transparent substrate. Item 6. The organic EL light emitting device according to Item 5.   The organic EL light-emitting device according to claim 1, wherein the interlayer insulating layer is made of a photosensitive insulating film.   The organic EL light emitting device according to claim 8, wherein the photosensitive insulating film is a photosensitive polyimide film. A method of manufacturing an organic EL light emitting device in which at least an organic light emitting layer is sandwiched between a pair of opposed electrodes on a transparent substrate, and light is emitted from the transparent substrate side,
Forming an auxiliary electrode on the surface of the transparent substrate;
Forming a transparent electrode that covers the auxiliary electrode and is electrically connected to the auxiliary electrode as one electrode of the pair of electrodes;
Forming a photosensitive insulating film on the transparent electrode, exposing and developing the photosensitive insulating film to form an interlayer insulating layer on the auxiliary electrode via the transparent electrode;
Forming a counter electrode as the other electrode of the pair of electrodes that covers the interlayer insulating layer and is disposed to face the transparent electrode;
The manufacturing method of the organic electroluminescent light emitting device characterized by having. A method of manufacturing an organic EL light emitting device in which at least an organic light emitting layer is sandwiched between a pair of opposed electrodes on a transparent substrate, and light is emitted from the transparent substrate side,
Forming an aluminum film on the surface of the transparent substrate;
Selectively anodizing the aluminum film to form an auxiliary electrode;
Forming a transparent electrode as one electrode of the pair of electrodes, covering the auxiliary electrode and electrically connecting to the surface of the auxiliary electrode;
Forming a photosensitive insulating film on the transparent electrode, exposing and developing the photosensitive insulating film to form an interlayer insulating layer on the auxiliary electrode via the transparent electrode;
Forming a counter electrode as the other electrode of the pair of electrodes that covers the interlayer insulating layer and is disposed to face the transparent electrode;
The manufacturing method of the organic electroluminescent light emitting device characterized by having. A method of manufacturing an organic EL light emitting device in which at least an organic light emitting layer is sandwiched between a pair of opposed electrodes on a transparent substrate, and light is emitted from the transparent substrate side,
Forming a recess in the surface of the transparent substrate;
Forming an auxiliary electrode so as to be embedded in the recess;
Forming a transparent electrode that covers the surface of the auxiliary electrode and the transparent substrate and is electrically connected to the auxiliary electrode as one electrode of the pair of electrodes;
Forming a photosensitive insulating film on the transparent electrode, exposing and developing the photosensitive insulating film to form an interlayer insulating layer on the auxiliary electrode via the transparent electrode;
Forming a counter electrode as the other electrode of the pair of electrodes that covers the interlayer insulating layer and is disposed to face the transparent electrode;
The manufacturing method of the organic electroluminescent light emitting device characterized by having.

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