JP2005158617A - Display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device capable of improving a manufacturing yield without the need of a high positioning accuracy and maintaining good display performance for a long term. <P>SOLUTION: The display device is equipped with an array substrate 100, a sealing substrate 200 sealing the array substrate 100 and a spacer 300 arranged between the array substrate 100 and the sealing substrate 200. The array substrate 100 is equipped with a first electrode 60 formed in an independent island shape for every pixel PX arranged in a matrix, a second electrode 66 arranged facing to the first electrode 60 and formed commonly to all the pixels, an organic active layer 64 held between the first electrode 60 and the second electrode 66 and a separating wall 70 arranged along a peripheral edge of the first electrode 60 and separating each pixel. A length of a longitudinal direction of the spacer 300 is longer than the longest length of a pixel opening part in a parallel direction to the longitudinal direction of the spacer. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a display device, and more particularly to an organic electroluminescence display device including a plurality of self-light emitting elements.

  In recent years, organic electroluminescence (EL) display devices have attracted attention as flat display devices. Since this organic EL display device is a self-luminous element, it has a wide viewing angle, can be thinned without requiring a backlight, has low power consumption, and has a high response speed. ing.

  Because of these characteristics, organic EL display devices are attracting attention as potential candidates for next-generation flat display devices that can replace liquid crystal display devices. Such an organic EL display device includes an array substrate configured by arranging organic EL elements having an organic active layer containing an organic compound having a light emitting function between an anode and a cathode in a matrix. .

  Such an array substrate is sealed by a sealing substrate bonded through a sealing material. The sealing substrate is arranged with a predetermined gap so as not to come into contact with the organic EL element. However, as the size of the substrate increases as the screen becomes larger, the sealing substrate and the array substrate bend, and the sealing substrate It becomes easy to contact an organic EL element.

  For this reason, there exists a possibility that a board | substrate may be damaged or an organic EL element may be destroyed, and it becomes the cause which impairs the reliability as a display apparatus. In addition, the organic EL element may be destroyed by an impact applied during the manufacturing process, which causes a decrease in manufacturing yield.

  In order to solve this, a technique is known in which a predetermined gap is formed between a sealing substrate and a columnar spacer formed on the array substrate side (see, for example, Patent Document 1). This columnar spacer is erected so that its central axis is substantially perpendicular to the main surface of the array substrate.

However, in such a technique, it is necessary to selectively form columnar spacers in the non-light emitting portion in the display area. That is, high alignment accuracy is required so that the columnar spacer does not cover the light emitting pixels. Such columnar spacers are formed of a photosensitive resin material. For this reason, the organic EL element previously formed on the array substrate is exposed to moisture in the photolithography process for forming the columnar spacer. When the organic EL element is exposed to moisture, its light emission characteristics are rapidly deteriorated, so that it is difficult to maintain good display performance.
JP 2002-151252 A

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a display device capable of improving the manufacturing yield without requiring a high degree of alignment accuracy.

A display device according to a first aspect of the present invention includes:
A first electrode formed in an independent island shape for each pixel arranged in a matrix, a second electrode arranged opposite to the first electrode and formed in common to all pixels, the first electrode, An array substrate comprising: an organic active layer held between the second electrode; and a partition wall disposed along the periphery of the first electrode and separating each pixel;
A sealing substrate for sealing the array substrate;
A spacer disposed between the array substrate and the sealing substrate,
The length of the spacer in the longitudinal direction is larger than the largest length of the pixel opening in a direction parallel to the longitudinal direction of the spacer.

A display device according to a second aspect of the present invention provides:
In a display area for displaying an image, a first electrode formed in an independent island shape for each pixel arranged in a matrix, and a second electrode arranged opposite to the first electrode and formed in common for all pixels An array substrate comprising: an organic active layer held between the first electrode and the second electrode; and a partition wall disposed along the periphery of the first electrode and separating each pixel;
A sealing substrate for sealing at least the display area of the array substrate;
A spacer disposed between the array substrate and the sealing substrate,
The length of the spacer in the longitudinal direction is larger than the largest length of the pixel opening in a direction parallel to the longitudinal direction of the spacer, and is more densely arranged at the center than the peripheral portion of the display area. And

  According to the present invention, it is possible to provide a display device that can improve the manufacturing yield without requiring a high degree of alignment accuracy and can maintain good display performance over a long period of time.

  A display device according to an embodiment of the present invention will be described below with reference to the drawings. In this embodiment, a self-luminous display device such as an organic EL (electroluminescence) display device will be described as an example of the display device.

  As shown in FIGS. 1 and 2, the organic EL display device 1 includes an array substrate 100 having a display area 102 for displaying an image, and a sealing substrate 200 for sealing at least the display area 102 of the array substrate 100. Composed. The display area 102 of the array substrate 100 is configured by a plurality of pixels PX (R, G, B) arranged in a matrix.

  Each pixel PX (R, G, B) is supplied via a pixel switch 10 and a pixel switch 10 having a function of electrically separating an on-pixel and an off-pixel and holding a video signal to the on-pixel. The driving transistor 20 supplies a desired driving current to the display element based on the video signal, and the storage capacitor element 30 holds the gate-source potential of the driving transistor 20 for a predetermined period. The pixel switch 10 and the drive transistor 20 are constituted by, for example, thin film transistors, and here, polysilicon is used for their semiconductor layers.

  Each pixel PX (R, G, B) includes an organic EL element 40 (R, G, B) as a display element. That is, the red pixel PXR includes an organic EL element 40R that emits red light, the green pixel PXG includes an organic EL element 40G that emits green light, and the blue pixel PXB includes an organic EL element 40B that emits blue light. I have.

  The various organic EL elements 40 (R, G, B) basically have the same structure. In other words, the organic EL element 40 is arranged in a matrix and is formed in an independent island shape for each pixel PX, and the first electrode 60 is disposed opposite to the first electrode 60 and is commonly formed in all the pixels PX. The two electrodes 66 and the organic active layer 64 held between the first electrode 60 and the second electrode 66 are configured.

  The array substrate 100 includes a plurality of scanning lines Ym (m = 1, 2,...) Arranged along the row direction of the pixels PX (that is, the Y direction in FIG. 1), and a direction substantially orthogonal to the scanning lines Ym (that is, A plurality of signal lines Xn (n = 1, 2,...) Arranged along the X direction in FIG. 1 and a power supply line Pm (for supplying power to the first electrode 60 side of the organic EL element 40). m = 1, 2,...). The power supply line Pm is connected to a first electrode power line (not shown) arranged around the display area 102. The second electrode 66 side end of the organic EL element 40 is connected to a second electrode power supply line (not shown) that is arranged around the display area 102 and supplies a common potential, here, a ground potential.

  The array substrate 100 has a scanning line driving circuit 107 that supplies a scanning signal to the scanning line Ym and a signal line driving circuit 108 that supplies a video signal to the signal line Xn in a peripheral area 104 along the outer periphery of the display area 102. And. All the scanning lines Ym are connected to the scanning line driving circuit 107. All signal lines Xn are connected to the signal line driving circuit 108.

  Here, the pixel switch 10 is disposed in the vicinity of the intersection between the scanning line Ym and the signal line Xn. The pixel switch 10 has a gate electrode connected to the scanning line Ym, a source electrode connected to the signal line Xn, and a drain electrode connected to one electrode constituting the storage capacitor 30 and the gate electrode of the drive transistor 20. The source electrode of the drive transistor 20 is connected to the other electrode constituting the storage capacitor element 30 and the power supply line Pm, and the drain electrode is connected to the first electrode 60 of the organic EL element 40.

  As shown in FIG. 2, the array substrate 100 includes an organic EL element 40 disposed on the wiring substrate 120. Note that the wiring substrate 120 is formed on an insulating support substrate such as a glass substrate or a plastic sheet, the pixel switch 10, the driving transistor 20, the storage capacitor element 30, the scanning line driving circuit 107, the signal line driving circuit 108, and various wirings (scanning). Line, signal line, power supply line, etc.).

  The first electrode 60 constituting the organic EL element 40 is disposed on the insulating film on the surface of the wiring substrate 120. Here, the first electrode 60 is formed of a light-transmitting conductive member such as ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide), and functions as an anode.

  The organic active layer 64 includes at least an organic compound having a light emitting function, and may be configured by a three-layer stack of a hole buffer layer formed in common for each color, an electron buffer layer, and an organic light emitting layer formed for each color. It may be composed of two layers or a single layer functionally combined. For example, the hole buffer layer is disposed between the anode and the organic light emitting layer, and is formed of a thin film such as an aromatic amine derivative, a polythiophene derivative, or a polyaniline derivative. The organic light emitting layer is formed of an organic compound having a light emitting function that emits red, green, or blue light. This organic light emitting layer is constituted by a thin film such as PPV (polyparaphenylene vinylene), a polyfluorene derivative, or a precursor thereof when, for example, a polymer light emitting material is employed.

  The second electrode 66 is disposed on the organic active layer 64 in common with each organic EL element 40. The second electrode 66 is formed of a metal film having an electron injection function such as Ca (calcium), Al (aluminum), Ba (barium), Ag (silver), Yb (ytterbium), and functions as a cathode. Yes. The second electrode 66 may have a two-layer structure in which the surface of a metal film functioning as a cathode is covered with a cover metal. The cover metal is made of aluminum, for example. Further, the surface of the second electrode 66 may be coated with a hygroscopic material as a desiccant. That is, when the organic EL element 40 is exposed to moisture, its light emission characteristics are rapidly deteriorated. Therefore, for the purpose of protecting the organic EL element 40 from moisture, a desiccant may be disposed on the second electrode 66 corresponding to the surface thereof. As the desiccant, any material having hygroscopicity may be used. For example, a simple alkali metal such as lithium (Li), sodium (Na), potassium (K) or an oxide thereof, or magnesium (Mg), calcium (Ca ), An alkaline earth metal such as barium (Ba) or an oxide thereof.

  Further, the array substrate 100 includes a partition wall 70 that separates the pixels PX (R, G, B) in the display area 102. The partition walls 70 are arranged in a lattice shape along the periphery of the first electrode 60. The partition wall 70 is formed of a resin material. For example, the partition wall 70 is formed of a lyophilic organic material and a liquid-phobic organic material disposed on the first insulating layer. The second insulating layer is laminated.

  Each pixel PX (R, G, B) has a pixel opening AP exposed from the partition wall 70. That is, in the pixel opening AP, the organic active layer 64 and the second electrode 66 are sequentially stacked on the first electrode 60, and the organic EL element 40 that substantially emits light is formed.

  A spacer 300 is disposed between the array substrate 100 and the sealing substrate 200, and a predetermined gap is formed. The array substrate 100 and the sealing substrate 200 are sealed with a frame-shaped sealing material 400 that surrounds the display area 102, and a sealed space is formed in a predetermined gap. This sealed space is filled with an inert gas such as nitrogen gas. In addition, a desiccant is disposed inside the sealed space, and is maintained in a dry state that does not adversely affect the organic EL element 40.

  In the organic EL display device 1 of the bottom emission type configured as described above, in the organic EL element 40 of each pixel PX, electrons and the organic active layer 64 sandwiched between the first electrode 60 and the second electrode 66 are stored. Excitons are generated by injecting holes and recombining them, and light is emitted by light emission of a predetermined wavelength generated when the excitons are deactivated. Here, EL light emission is emitted from the lower surface side of the array substrate 100, that is, the first electrode 60 side.

  Meanwhile, the spacer 300 described above is formed such that the length of the spacer in the longitudinal direction is larger than the largest length of the pixel opening in the direction parallel to the longitudinal direction of the spacer. Here, the length of the spacer 300 in the longitudinal direction is set to be larger than the length of the longest diagonal line in the pixel opening. That is, as shown in FIGS. 2 and 3, the spacer 300 is provided between the surface layer of the array substrate 100, for example, the second electrode 66 (or cover metal, desiccant, protective film, etc.) and the sealing substrate 200. Are arranged so as to straddle between adjacent pixels.

  In general, the partition wall 70 is formed to be thicker than the organic EL element 40. For this reason, the 2nd electrode 66 on the partition 70 protrudes in the sealing substrate side rather than the organic EL element 40 surface. Accordingly, the spacer 300 is arranged between the array substrate 100 and the sealing substrate 200. The spacer 300 applied at this time is a pixel opening portion whose length in the longitudinal direction is parallel to the longitudinal direction of the spacer. Since it is set to be larger than the largest length, the pixel is surely arranged on the partition wall 70 without falling into the pixels surrounded by the partition wall 70. Thereby, the spacer 300 does not directly contact the organic EL element 40, and naturally, the sealing substrate 200 does not directly contact the organic EL element 40. Further, the spacer 300 supports the array substrate 100 and the sealing substrate 200 other than the sealing material 400 in the display area 102. Thereby, the support strength of the array substrate 100 and the sealing substrate 200 and further the mechanical strength as a display device can be improved.

  That is, by arranging the spacers 300 of such a size, even when the substrate size is increased as the screen size is increased, when the array substrate 100 and the sealing substrate 200 are bent, Breakage can be prevented, and destruction of the organic EL element 40 due to contact of each substrate can be prevented. In addition, even if an impact is applied to each substrate in the manufacturing process or stress is applied when a deflecting plate is attached to one substrate surface as necessary, each substrate is damaged and the organic EL element is destroyed. Can be prevented. Furthermore, fine processing is not required when forming the spacer, and it can be easily formed. Therefore, the manufacturing yield can be improved.

(First arrangement method of spacer)
In the first arrangement method, the spacer 300 as described above is formed integrally with the sealing substrate 200. That is, the spacer 300 is formed on the sealing substrate 200 by a photolithography method, a printing method, a vapor deposition method (including a sputtering method, an electron beam method, a heat vapor deposition method, an ion plating method, etc.), a CVD method, a plating method, or the like. It is formed with a predetermined film thickness. The sealing substrate 200 on which the spacer 300 is formed by these methods is bonded to the array substrate 100 to constitute an organic EL display device.

  In the photolithography method, first, a photosensitive resin material having a substantially constant film thickness is formed on the sealing substrate 200. And when the negative type photosensitive resin material which an exposure part superposes | polymerizes and hardens is applied, the photosensitive resin material is passed through the photomask which has an opening part (part with relatively high transmittance | permeability) in the part which forms a spacer. To expose. And after developing this photosensitive resin material, the spacer 300 of a predetermined film thickness is formed by baking.

In the printing method, a resin material is applied to a portion where a spacer is to be formed through a screen having an opening. Then, the spacer 300 having a predetermined film thickness is formed by baking this resin material.
In the vapor deposition method, the spacer 300 having a predetermined thickness is formed by depositing a metal material through a mask having an opening in a portion where the spacer is to be formed.

  The spacer 300 is formed integrally with the sealing substrate 200. However, when the spacer 300 is formed by a dry process such as vapor deposition, the spacer 300 may be formed integrally with the array substrate 100. . It goes without saying that the spacer 300 may be formed not only on one of the sealing substrate 200 and the array substrate 100 but also on both substrates.

  According to the first arrangement method in which the spacer 300 is integrally formed on one substrate, the spacer 300 can be reliably arranged at a predetermined position in the display area 102. At this time, when the spacer 300 is formed, it is not necessary to align the mask or the screen with high accuracy.

  That is, even if the spacer 300 is formed at a position shifted from a predetermined position by setting the length in the longitudinal direction of the spacer 300 to be larger than the largest length of the pixel opening in the direction parallel to the longitudinal direction of the spacer, The spacer 300 facing the pixel opening AP does not come into contact with the organic EL element 40, and the organic EL element 40 can be prevented from being broken.

  In addition, according to the first arrangement method, the spacers 300 can be arranged at a required position in the display area 102 with a predetermined arrangement density (the number of spacers arranged per unit area). As a matter of course, the spacers 300 can be uniformly distributed in the display area 102. That is, the arrangement density of the spacers can be freely controlled. Therefore, the spacer 300 can be reliably disposed at a place where the support strength of each substrate is weak, and the support strength of the array substrate 100 and the sealing substrate 200 and further the mechanical strength as a display device can be improved. .

  For example, the support strength of each substrate is relatively weak in the central portion of the display area 102 away from the seal material 400, and the support strength of each substrate is relatively low in the peripheral portion of the display area 102 due to the holding ability of the seal material 400. Strong. For this reason, the support strength can be reinforced by arranging the spacer 300 more densely (higher arrangement density) than the periphery of the display area. Further, since the support strength is reinforced by the spacer 300, the burden on the sealing material 400 for supporting each substrate can be reduced.

  Furthermore, according to the first arrangement method, when the spacer 300 is formed by a wet process such as a photolithography method or a printing method, the spacer 300 is integrally formed on the sealing substrate 200 side. The formed organic EL element 40 is not exposed to moisture in the process for forming the spacer 300. Therefore, rapid deterioration of the light emission characteristics of the organic EL element 40 can be prevented, and good display performance can be maintained over a long period of time.

(Spacer second arrangement method)
In the second arrangement method, the spacer 300 as described above is sandwiched between the array substrate 100 and the sealing substrate 200. That is, the spacer 300 is not integrally formed on either substrate, and may be arranged in contact with the substrate. That is, the spacers 300 formed in a predetermined shape are dispersed on the sealing substrate 200 or the array substrate 100. By these methods, the sealing substrate 200 on which the spacers 300 are arranged is bonded to the array substrate 100 to constitute an organic EL display device.

  According to the second arrangement method in which the spacer 300 is sandwiched between both substrates, a complicated process for forming the spacer is not required, and the support strength of each substrate can be improved easily and at low cost. it can. Further, like the first arrangement method, the manufacturing yield can be improved without requiring a high degree of alignment accuracy, and good display performance can be maintained over a long period of time.

(Spacer structure)
The spacer 300 applicable to each arrangement method described above contains a resin material. That is, when the spacer 300 is formed by photolithography or printing, a paste material having a relatively low viscosity is formed. In this case, polyester, polyvinyl, polystyrene, nylon, polysiloxane, polyether, epoxy, etc. Polymer materials such as polyaniline, polyfluorene, polythiophene, and the like can also be applied.

  The spacer 300 may contain a metal material. That is, when the spacer 300 is formed by vapor deposition or the like, silver (Ag), gold (Au), copper (Cu), aluminum (Al), beryllium (Be), magnesium (Mg), molybdenum (Mo), Metal materials such as nickel (Ni), tungsten (W), chromium (Cr), iron (Fe), silicon (Si), or alloys thereof can be applied.

  Furthermore, the material for forming the spacer 300 may be a material in which the above-described resin material is mixed with the above-described metal material, or the above-described resin material may be a metal fine particle or carbon particle. A material in which conductive particles, semiconductor fine particles, and the like are mixed may be used, and further, a material in which glass particles are mixed into metal particles such as a plating paste may be used.

  Furthermore, the spacer 300 may contain a desiccant such as a simple alkali metal or its oxide, or an alkaline earth metal or its oxide.

  Thus, when the spacer 300 is formed of a material containing a resin material, the moldability is good and it is easy to form in a uniform shape. For this reason, the spacer 300 having a uniform thickness can be easily formed. Further, even when the pre-formed spacers 300 are dispersed and arranged, a uniform gap is formed between the array substrate 100 and the sealing substrate 200, and stress is concentrated on some of the spacers 300. Can be suppressed. Moreover, the material containing the resin material has moderate elasticity. For this reason, even if stress is applied to each substrate in a state where the spacer 300 is in contact with the array substrate 100, the organic EL element 40 can be prevented from being broken.

  Moreover, when forming the spacer 300 with the material containing a metal material, a dry process can be applied and the contact with the water | moisture content of the organic EL element 40 can be suppressed. Further, since the spacer 300 contains a desiccant such as a metal material, the sealed space between the array substrate 100 and the sealing substrate 200 can be maintained in an appropriate dry state. Furthermore, since the metal material has high thermal conductivity, the heat generated in each pixel PX can be efficiently radiated to the sealing substrate 200 side via the spacer 300, and the temperature rise of the organic EL element 40 is suppressed. be able to. For this reason, the light emission characteristics of the organic EL element 40 can be maintained satisfactorily over a long period of time.

  By the way, the spacer 300 described above is, for example, a columnar body, and is arranged so that the central axis thereof is substantially parallel to the main surface of the array substrate 100. That is, the central axis O of the spacer 300 shown in FIGS. 2 and 3 is substantially parallel to the main surface of the array substrate 100. Desirably, the spacer 300 is formed as a cylindrical column having a circular cross section perpendicular to the central axis O or an elliptical columnar body having an elliptical cross section orthogonal to the central axis O. When the spacer is formed as a prismatic columnar body, if the corner of the spacer comes into contact with the array substrate, a strong stress is locally applied to the array substrate, which may destroy the organic EL element. For this reason, it is preferable that the spacer 300 has a rounded shape without corners.

  In the case of a columnar body, the length along the central axis O of the spacer 300 corresponds to the length in the longitudinal direction of the spacer, and is longer than the largest length of the pixel opening AP in a direction parallel to the longitudinal direction of the spacer. It is formed to become. For example, as shown in FIG. 3, in the case of a square pixel PX, when the spacer 300 is arranged so that the central axis O is parallel to one side of one pixel PX, the length of one side of one pixel PX is the pixel. This corresponds to the largest length APL of the opening AP. Although not shown, the spacer 300 is arranged on the array substrate 100 or the sealing substrate 200 so that the central axis O of the spacer 300 is parallel to the diagonal direction of one pixel PX. The length of the diagonal line of one pixel PX corresponds to the largest length APL of the pixel opening AP.

  Thus, by making the length L of the central axis O of the spacer 300 longer than the largest length APL of the pixel opening AP, the spacer 300 does not fall into the pixel opening AP but contacts the organic EL element 40. This can be prevented.

  Here, it has been described that the maximum length APL of the pixel opening corresponds to the length of one side or the length of the diagonal line in the case of a square pixel, but the pixel shape and the direction in which the spacer 300 is arranged are described. It is set accordingly. For example, in the case of a polygonal pixel, it corresponds to the longest length of a line segment connecting two vertices (or points on two opposite sides), and in the case of a circular pixel, it corresponds to the diameter. Furthermore, in the case of an elliptical pixel, it corresponds to the length in the major axis direction (or the length in the direction other than the major axis passing through the center).

  As an example, when the central axis of the spacer 300 is parallel to the diagonal direction of the pixel PX and the length APL of the diagonal line in the pixel opening AP is a regular octagon with 70 μm, the length L of the central axis O of the spacer 300 Is 300 μm. Incidentally, the width of the spacer 300 on the main surface of the array substrate (the length in the direction orthogonal to the central axis) at this time is 60 μm, and the height in the normal direction of the main surface of the array substrate of the spacer 300 is 4 μm.

  Note that when the spacer 300 is formed of a material having high heat dissipation properties, the spacer 300 has higher heat dissipation efficiency if it is disposed so as to cover each pixel PX. Also, in the case of the spacer 300 containing a desiccant, the water vaporized from each pixel PX can be effectively removed without being diffused into the sealed space if it is arranged so as to cover each pixel PX.

(First arrangement example)
In the first arrangement example, the spacers 300 are arranged uniformly and regularly in the display area 102 as shown in FIG. Such arrangement of the spacer 300 is possible by adopting the first arrangement method described above.

  According to the first arrangement example, the spacers 300 can be arranged with a uniform arrangement density in the display area 102. Therefore, the support strength of the array substrate 100 and the sealing substrate 200 and further the mechanical strength of the display device 1 can be improved.

(Second arrangement example)
In the second arrangement example, as shown in FIG. 5, the spacers 300 are arranged more densely in the center than in the periphery in the display area 102. In the example shown in FIG. 5, the spacers 300 are arranged radially from the center of the display area 102 toward the periphery. Such arrangement of the spacer 300 is possible by adopting the first arrangement method described above.

  According to this second arrangement example, it is possible to arrange the spacers 300 at a high arrangement density in the central area where the supporting strength of each substrate is weak in the display area 102. Therefore, the support strength of the array substrate 100 and the sealing substrate 200 and further the mechanical strength of the display device 1 can be improved.

  Further, according to the second arrangement example, the spacer 300 made of a material having high heat dissipation is arranged at a high arrangement density in the central portion of the display area 102 where the heat dissipated from each pixel PX tends to concentrate. The heat dissipation efficiency can be improved, and the temperature rise of each organic EL element 40 can be suppressed.

(Third arrangement example)
In the third arrangement example, as shown in FIG. 6, the spacers 300 are arranged more densely in the center than in the periphery in the display area 102. In addition, a desiccant 350 is provided around the display area 102 where the spacers 300 are sparsely arranged. The desiccant 350 is provided on the sealing substrate 200. Such arrangement of the spacer 300 is possible by adopting the first arrangement method described above.

  According to the third arrangement example, in addition to the effects obtained in the second arrangement example, moisture vaporized from each pixel PX can be effectively removed without being diffused into the sealed space, and the inside of the sealed space can be appropriately adjusted. Can be kept dry.

(Example)
A method for manufacturing the organic EL display device will be described.
First, the wiring board 120 is prepared. That is, an insulating substrate having light transparency is prepared. Then, processes such as formation of a metal film and an insulating film and patterning are repeated, and in addition to the pixel switch 10, the driving transistor 20, the storage capacitor element 30, the scanning line driving circuit 107, and the signal line driving circuit 108 on the insulating substrate. A wiring board 120 having a total of 2.9 million pixels of vertical 768 pixels and horizontal 1280 × 3 (R, G, B) pixels, on which various wirings such as signal lines Xn, scanning lines Ym, and power supply lines Pm are also formed. To do.

  Subsequently, a first electrode 60 made of a conductive material having optical transparency, for example, ITO (indium tin oxide) is formed in each pixel PX. Then, a partition wall 70 having a structure in which a lyophilic first insulating layer, a lyophobic second insulating layer, or the like is laminated on the wiring substrate 120 so as to surround the first electrode 60 is formed. Thereafter, in order to modify the surface of the partition wall 70 and the first electrode 60, chemical treatment with a reactive fluorine-containing gas is performed in a reactive ion etching apparatus.

  Subsequently, an organic active layer 64 including a hole buffer layer and the like in addition to the organic light emitting layer is formed in each pixel. The organic active layer 64 is formed, for example, by applying a polymer light emitting polymer material for forming a hole buffer layer, an organic light emitting layer, or the like using a piezo ink jet nozzle and then performing a drying process.

  Subsequently, the second electrode 66 is formed on the entire surface of the array substrate 100. That is, the second electrode 66 is disposed on the organic active layer 64 and the partition 70 protruding from the organic active layer 64, and is provided in common for all pixels. Thereby, the organic EL element 40 of each pixel PX is formed.

  Subsequently, the sealing substrate 200 is prepared. As the sealing substrate 200, a metal substrate, a glass substrate, a plastic substrate, a plastic film, or the like is applicable. Then, a spacer 300 is formed on the sealing substrate 200. That is, in this embodiment, the spacer 300 is formed by the photolithography method of the first arrangement method described above using an ultraviolet curable negative type resin material.

  Subsequently, in order to seal the display area 102 on the array substrate 100, an ultraviolet curable sealing material 400 is applied along the outer periphery of the sealing substrate 200, and in an inert gas atmosphere such as nitrogen gas or argon gas. , The array substrate 100 and the sealing substrate 200 are bonded together. Thereby, the organic EL element 40 is enclosed in the sealed space of an inert gas atmosphere. Thereafter, the sealing material 400 is cured by irradiating with ultraviolet rays.

  In the bottom-emission color display type active matrix organic EL display device 1 formed in this way, the array substrate 100 and the sealing substrate 200 are formed by the spacers 300 while the large-sized substrate having the large display area 102 is used. Can be held with an appropriate gap, and the mechanical strength against the stress from the outside of the display device can be improved. Moreover, destruction of the organic EL element 40 of each pixel PX was prevented, and good display quality could be obtained.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the spirit of the invention in the stage of implementation. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.

  In the above-described embodiment, the columnar spacer has been described as an example, but a structure suitable as a spacer is not limited to this. For example, the spacer may have a flat plate structure, or may have a bent structure such as an L-shape or a wave shape. In any case, the spacer has a height that forms an appropriate gap between the array substrate and the sealing substrate, regardless of its structure, and the pixel is within a plane orthogonal to the height direction. It is only necessary to include a segment having a length larger than the largest length of the opening (a length corresponding to the longitudinal direction of the spacer). In the case of a spacer having such a bent structure, the length of the long side of the rectangle with the smallest area that circumscribes the spacer is the length in the longitudinal direction of the spacer.

  By applying such a spacer, when the spacer is disposed between the array substrate and the counter substrate, a segment having a length larger than the largest length of the pixel opening is formed on the partition (strictly speaking, the first covering the partition). Since the spacers can be prevented from falling into the pixels, the same effects as those of the above-described embodiment can be obtained.

FIG. 1 is a diagram schematically showing a configuration of an organic EL display device according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing a partial cross-sectional structure in the display area of the organic EL display device shown in FIG. FIG. 3 is a diagram schematically showing a partial planar structure in the display area of the organic EL display device shown in FIG. FIG. 4 is a diagram schematically showing a first arrangement example of spacers in the organic EL display device shown in FIG. FIG. 5 is a diagram schematically showing a second arrangement example of the spacers in the organic EL display device shown in FIG. FIG. 6 is a diagram schematically showing a third arrangement example of spacers in the organic EL display device shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Organic EL display apparatus, 10 ... Pixel switch, 20 ... Drive transistor, 30 ... Storage capacitor element, 40 ... Organic EL element, 60 ... 1st electrode, 64 ... Organic active layer, 66 ... 2nd electrode, 70 ... Partition , 100 ... Array substrate, 200 ... Sealing substrate, 300 ... Spacer, 350 ... Desiccant, 400 ... Sealing material, PX ... Pixel

Claims (11)

A first electrode formed in an independent island shape for each pixel arranged in a matrix, a second electrode arranged opposite to the first electrode and formed in common to all pixels, the first electrode, An array substrate comprising: an organic active layer held between the second electrode; and a partition wall disposed along the periphery of the first electrode and separating each pixel;
A sealing substrate for sealing the array substrate;
A spacer disposed between the array substrate and the sealing substrate,
The length of the spacer in the longitudinal direction is larger than the largest length of the pixel opening in a direction parallel to the longitudinal direction of the spacer.   The display device according to claim 1, wherein the spacer is integrally formed on the sealing substrate.   The display device according to claim 1, wherein the spacer is sandwiched between the array substrate and the sealing substrate.   The display device according to claim 1, wherein the spacer contains a resin material.   The display device according to claim 1, wherein the spacer contains a metal material.   The display device according to claim 1, wherein the spacer contains a desiccant.   The display device according to claim 1, wherein the spacer is a columnar body, and a central axis thereof is substantially parallel to a main surface of the array substrate.   The display device according to claim 7, wherein a length of the central axis is longer than a long side of the pixel. In a display area for displaying an image, a first electrode formed in an independent island shape for each pixel arranged in a matrix, and a second electrode arranged opposite to the first electrode and formed in common for all pixels An array substrate comprising: an organic active layer held between the first electrode and the second electrode; and a partition wall disposed along the periphery of the first electrode and separating each pixel;
A sealing substrate for sealing at least the display area of the array substrate;
A spacer disposed between the array substrate and the sealing substrate,
The length of the spacer in the longitudinal direction is larger than the largest length of the pixel opening in a direction parallel to the longitudinal direction of the spacer, and is more densely arranged at the center than the peripheral portion of the display area. Display device.   The display device according to claim 9, wherein the spacers are arranged radially from a central portion of the display area toward a peripheral portion.   The display device according to claim 9, wherein the sealing substrate includes a desiccant in a peripheral portion of the display area where the spacers are sparsely arranged.

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