JP2006004650A - Display element and optical device - Google Patents

Abstract

An object of the present invention is to provide a display element and an optical device capable of maintaining good display performance over a long period of time.
SOLUTION: An effective portion 106 having a plurality of display elements for displaying an image formed on a substrate main surface 100A, and a sealing body 300 arranged to cover at least the effective portion 106 of the substrate main surface 100A. The sealing body 300 includes at least two buffer layers 311 and 312 and barrier layers 320, 321, and 322 that have a larger pattern than the buffer layers 311 and 312 and cover the buffer layers 311 and 312. And the first buffer layer 311 has a thickness different from that of the second buffer layer 312.
[Selection] Figure 4

Description

  The present invention relates to a display element and an optical device, and more particularly to an optical device configured to include display elements such as 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 display device provided with a self-luminous element, it has a wide viewing angle, can be thinned without requiring a backlight, can reduce power consumption, and has a high response speed. Has characteristics.

  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 in a matrix as self-luminous elements. The organic EL element has a structure in which an organic active layer containing an organic compound having a light emitting function is sandwiched between an anode and a cathode.

When the organic EL element is exposed to moisture or oxygen contained in the outside air, its light emission characteristics are rapidly deteriorated. For this reason, various techniques for shielding and sealing the main surface on which the organic EL elements are arranged on the array substrate from contact with the outside air have been proposed. Various such techniques have been proposed. For example, a film sealing technique in which an organic film and an inorganic film are stacked on an electrode arranged on the surface side of an organic EL element is disclosed (for example, Non-patent document 1).
Yuji Yanagi, “Compatible with mass production of thin, large and flexible substrates”, Flat Panel Display 2003, Nikkei Business Publications, December 27, 2002, p. 264-270

  The protective layer for sealing the organic EL element is required to form a film having good step coverage and having no defects such as pinholes and cracks. However, it is actually difficult to obtain a complete defect-free film. For this reason, the organic EL element cannot be completely shielded from the outside air, and it becomes difficult to maintain sufficient performance over a long period of time.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a display element and an optical device that are excellent in sealing performance and can maintain good display performance.

The display element according to the first aspect of the present invention is:
A display element formed on a substrate main surface,
A sealing body arranged to cover the display element;
The sealing body has a structure in which at least two buffer layers and a barrier layer that is a pattern larger than the buffer layer and covers each buffer layer are laminated,
At least one buffer layer has a thickness different from that of other buffer layers.

An optical device according to a second aspect of the present invention is:
An effective portion formed on the main surface of the substrate and provided with a plurality of display elements;
A sealing body disposed so as to cover at least the effective portion of the main surface of the substrate,
The sealing body has a structure in which at least two buffer layers and a barrier layer that is a pattern larger than the buffer layer and covers each buffer layer are laminated,
At least one buffer layer has a thickness different from that of other buffer layers.

A display element according to a third aspect of the present invention is
A display element formed on a substrate main surface,
A sealing body arranged to cover the display element;
The sealing body has a structure in which a buffer layer and a barrier layer that is a pattern larger than the buffer layer and covers the buffer layer are laminated,
The angle formed between the side surface of the buffer layer and the main surface of the substrate is an acute angle.

An optical device according to a fourth aspect of the present invention is
An effective portion formed on the main surface of the substrate and provided with a plurality of display elements;
A sealing body disposed so as to cover at least the effective portion of the main surface of the substrate,
The sealing body has a structure in which a buffer layer and a barrier layer that is a pattern larger than the buffer layer and covers the buffer layer are laminated,
The angle formed between the side surface of the buffer layer and the main surface of the substrate is an acute angle.

  According to the present invention, it is possible to provide a display element and an optical device that have excellent sealing properties and can maintain good display performance.

  Hereinafter, a display element and an optical device according to an embodiment of the present invention will be described 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 optical 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 body 300 for sealing at least the display area 102 of the array substrate 100. It is configured. The display area 102 of the array substrate 100 is composed of 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 configurations of the various organic EL elements 40 (R, G, B) are basically the same, and the organic EL elements 40 are arranged in a matrix and are formed in an independent island shape for each pixel PX. A second electrode 66 disposed opposite to the first electrode 60 and formed in common to all the pixels PX, an organic active layer 64 held between the first electrode 60 and the second electrode 66, It is constituted by.

  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 P for supplying power to the first electrode 60 side of the organic EL element 40. It is equipped with.

  The power supply line P is connected to a first electrode power line (not shown) arranged around the display area 102. The second electrode 66 side 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).

  Further, the array substrate 100 has a scanning line driving circuit 107 that supplies a scanning signal to each of the scanning lines Ym and a signal that supplies a video signal to each of the signal lines Xn in the peripheral area 104 along the outer periphery of the display area 102. A line driving circuit 108. 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 driving transistor 20 is connected to the other electrode constituting the storage capacitor element 30 and the power supply line P, 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 a display element, that is, 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 transmissive conductive member such as ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide) and functions as an anode. Yes.

  The organic active layer 64 includes at least an organic compound having a light emitting function, and is configured by a three-layer stack including a hole buffer layer formed in common to each color, an electron buffer layer, and an organic light emitting layer formed for each color. Alternatively, 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.

  The surface of the second electrode 66 is desirably 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. For this reason, the desiccant 68 is arrange | positioned on the 2nd electrode 66 equivalent to the surface for the purpose of protecting the organic EL element 40 from a water | moisture content. The desiccant 68 may be any material having hygroscopicity. For example, a simple alkali metal such as lithium (Li), sodium (Na), potassium (K) or an oxide thereof, or magnesium (Mg), calcium ( It is made of an alkaline earth metal such as Ca) or barium (Ba) or an oxide thereof.

  In addition, the array substrate 100 includes a partition wall 70 that separates the pixels RX (R, G, B) for each adjacent color in the display area 102. The partition wall 70 is preferably formed so as to separate each pixel. Here, the partition wall 70 is arranged in a lattice shape along the periphery of each first electrode 60, and the opening shape of the partition wall exposing the first pixel electrode is used. Is formed to be circular or polygonal. 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.

  In the organic EL element 40 configured in this way, holes and electrons are injected into the organic active layer 64 sandwiched between the first electrode 60 and the second electrode 66, and these are recombined to generate excitons. It emits light by light emission having a predetermined wavelength that is generated when the exciton is deactivated. Here, the EL light emission is emitted from the lower surface side of the array substrate 100, that is, the first electrode 60 side, and constitutes a display screen.

  Meanwhile, the array substrate 100 includes an effective portion 106 formed on the main surface of the wiring substrate 120. The effective portion 106 includes a display area 102 including a plurality of pixels PX (R, G, B) each having at least an organic EL element (display element) 40 for displaying an image. The peripheral area 104 including the driving circuit 107 and the signal line driving circuit 108 may be included.

  As shown in FIGS. 2 and 3, the sealing body 300 is disposed so as to cover at least the effective portion 106 in the main surface of the array substrate 100, that is, the surface on which the organic EL element 40 is formed. The surface of the sealing body 300 is almost flattened.

  As shown in FIG. 2, the sealing member 200 is bonded to the sealing body 300 with an adhesive applied to the entire surface of the sealing body 300. The sealing member 200 is made of a light-transmitting insulating film such as a plastic sheet, diamond-like carbon, or the like.

  The sealing body 300 has a structure in which buffer layers 311, 312... And a barrier layer 321, 322... That has a pattern having a larger formation area than the buffer layer and covers the buffer layer so as to shield it from the outside air. Have. The outermost layer and the innermost layer of the sealing body 300 are desirably barrier layers. For this reason, the sealing body 300 has at least two barrier layers.

  In the example illustrated in FIG. 2, the sealing body 300 includes two buffer layers 311 and 312 and three barrier layers 320, 321 and 322, and has a structure in which barrier layers and buffer layers are alternately stacked. The barrier layer 320 is provided in the innermost layer (the layer closest to the effective portion 106), and the barrier layer 322 is provided in the outermost layer (the layer farthest from the effective portion 106). Each barrier layer desirably covers the entire surface including the side surface of the lower buffer layer around the barrier layer. That is, in consideration of the adhesion between the barrier layers and the sealing performance as a sealing body, it is desirable that the barrier layers are laminated at the respective peripheral portions.

  The buffer layers 311, 312... Include various organic materials such as carbon nitride such as CNx: H, fluorocarbon such as CFx, and acrylic resins such as hydrogenated dicyclopentadienyl diacrylate. These are made of various resin materials. The buffer layers 311, 312... Have a pattern having a size at least equal to that of the effective portion 106, and more preferably a size larger than that. Here, as a material for forming these buffer layers 311, 312,..., A material that is applied in a liquid state having a relatively low viscosity and is cured in a state in which at least one of the buffer layers absorbs unevenness of the lower layer. It is desirable to select, and it has a function as a flattening layer for flattening the substrate surface. For example, the buffer layer having a function as a planarization layer is formed with a film thickness of about 2 to 3 μm, and is formed with a film thickness that is the same as or thicker than the partition wall. The buffer layer having a function as a buffer layer is formed with a film thickness of about 100 nm to 1 μm.

  The barrier layers 320, 321, 322... Are made of, for example, a metal material such as aluminum or titanium, a metal oxide material such as ITO or IZO, or an inorganic material such as a ceramic material such as SiNx, SiOx, or alumina. It is formed with a film thickness of 50 nm to 300 nm. In the case of the bottom emission method in which EL light is extracted from the first electrode 60 side, it is desirable that the material applied as at least one of the barrier layers 320, 321, 322,... Has light shielding properties and light reflecting properties.

  In the sealing body 300 having the configuration including at least two buffer layers 311 and 312 as shown in FIG. 2, at least one buffer layer has a film thickness different from that of the other buffer layers. .

  For example, as illustrated in FIGS. 4 and 5, the sealing body 300 corresponds to the first barrier layer 320 disposed so as to cover the effective portion 106 and the effective portion 106 on the first barrier layer 320. The first buffer layer 311 disposed, the second barrier layer 321 having a larger pattern than the first buffer layer 311 and disposed so as to cover the first buffer layer 311, and the effective portion on the second barrier layer 321 106, and a third barrier layer 322 having a pattern larger than the second buffer layer 312 and covering the second buffer layer 312. Has been.

  In the case of the example shown in FIG. 4, the film thickness of the first buffer layer 311 disposed closest to the effective portion 106 is disposed above the first buffer layer 311 (a layer separated from the effective portion 106). It is larger than the second buffer layer 312. In the case of the example shown in FIG. 5, the film thickness of the first buffer layer 311 disposed closest to the effective portion 106 is higher than the first buffer layer 311 (a layer separated from the effective portion 106). It is smaller than the disposed second buffer layer 312.

  Here, the film thickness corresponds to the thickness of the buffer layer along the normal direction of the main surface on which the effective portion 106 of the array substrate 100 is disposed, and is particularly defined as the film thickness of the thickest portion in each buffer layer. To do. As shown in FIG. 2, the effective portion 106 has a concave portion 106R and a convex portion 106P. That is, the convex portion 106P of the effective portion 106 corresponds to a portion where the partition wall 70 is formed, and the concave portion 106R of the effective portion 106 corresponds to the central portion of the organic EL element 40 surrounded by the partition wall 70.

  As described above, since the buffer layer absorbs the unevenness of the effective portion 106 and planarizes the surface thereof, at least one buffer layer may have a film thickness that is at least larger than the thickness of the partition wall 70. Required. In the case of the structural example shown in FIGS. 4 and 5, each buffer layer has the thickest portion corresponding to the concave portion 106 </ b> R of the effective portion 106, and the thickness of this portion is the thickness D of the buffer layer.

  That is, in the case of the example shown in FIG. 4, the film thickness D1 of the first buffer layer 311 is larger than the film thickness D2 of the second buffer layer 312 (D1> D2). In this case, the film thickness D1 of the first buffer layer 311 is smaller than the film thickness D2 of the second buffer layer 312 (D1 <D2).

  Thus, by forming at least one buffer layer constituting the sealing body 300 so as to have a relatively thick film thickness, the unevenness of the effective portion 106 can be sufficiently absorbed, and the buffer layer It becomes possible to arrange | position a barrier layer on the substantially planarized surface. For this reason, generation | occurrence | production of the defect in the barrier layer which covers a buffer layer can be suppressed, and generation | occurrence | production of a coverage defect can be prevented. For this reason, the penetration | invasion in an organic EL element, such as a water | moisture content and oxygen, can be prevented, and deterioration of an organic EL element can be suppressed. Therefore, good display performance can be maintained over a long period of time.

  In addition, since at least one buffer layer is formed to have a relatively thick film thickness, the number of buffer layers can be reduced by a smaller number of layers compared to the case of stacking a plurality of relatively thin buffer layers. It is possible to sufficiently planarize the surface. For this reason, the number of stacked buffer layers can be reduced, and the total number of layers constituting the sealing body 300 can be reduced. Therefore, productivity can be improved.

  On the other hand, in the sealing body 300 configured to include at least two buffer layers, at least one buffer layer has a relatively thick film thickness, and the other buffer layers have a relatively thin film thickness. It is desirable to be formed. In other words, by forming the plurality of buffer layers so as to have a relatively thick film thickness, the unevenness of the effective portion 106 can be reliably absorbed, and the surface of the upper buffer layer can be flattened. is there.

  However, such a configuration results in an increase in the thickness of the entire sealing body 300, which is disadvantageous for realizing a thin display device. Further, when a relatively thick buffer layer is formed by vapor deposition of a buffer layer material, forming a plurality of thick buffer layers causes a decrease in productivity. Therefore, by forming the one buffer layer thick and forming the other buffer layer thin, it is possible to reduce the thickness of the entire device and improve the productivity.

  As shown in FIG. 4, the sealing body 300 is formed by setting the lower first buffer layer 311 to a relatively thick film thickness and the upper second buffer layer 312 to a relatively thin film thickness. The unevenness of the effective portion 106 can be sufficiently flattened at a relatively early stage (step of forming a lower layer close to the effective portion), and the coverage performance of the barrier layer that is subsequently stacked can be improved. As a result, sufficient sealing performance can be realized with a sealing body having a small number of layers.

  Further, as shown in FIG. 5, the lower first buffer layer 311 has a relatively thin film thickness, and the upper second buffer layer 312 has a relatively thick film thickness so that it is disposed in the effective portion 106. The influence of moisture and oxygen on the organic EL element 40 can be reduced.

  That is, as shown in FIG. 5, by arranging a relatively thin buffer layer close to the effective portion 106 and disposing a relatively thick buffer layer away from the effective portion 106, Intrusion of moisture and oxygen into the organic EL element can be prevented, and deterioration of the organic EL element can be suppressed.

  4 and 5, an example in which the sealing body 300 includes two buffer layers has been described. However, the sealing body 300 may include three or more buffer layers. In this case, it suffices that at least one buffer layer has a larger thickness than the others, and the thick buffer layer may be arranged as any layer constituting the sealing body 300.

  Further, as shown in FIG. 6, the angle θ formed between the side surface 311S of the buffer layer 311 and the main surface 100A of the substrate 100 is an acute angle. That is, the buffer layer 311 has a cross-sectional shape that extends from the upper surface (surface away from the effective portion 106) 311T to the lower surface (surface adjacent to the effective portion 106) 311B, and the side surface 311S is tapered ( It is formed to form a (forward taper) shape. Accordingly, the second barrier layer 321 covering the buffer layer 311 is disposed along the side surface 311S of the buffer layer 311 and defects such as pinholes can be prevented.

  In order to reliably prevent the occurrence of defects in the barrier layer covering the buffer layer, the formed angle θ is desirably as small as possible, desirably 60 degrees or less, and more desirably 45 degrees or less. With such a configuration, steep irregularities are not formed on the upper surface and side surfaces of the buffer layer covered with the barrier layer, and the barrier layer can continuously cover the upper surface and side surfaces of the buffer layer. For this reason, the barrier layer is not easily affected by the buffer layer disposed in the lower layer, and the occurrence of defects can be suppressed.

  Needless to say, it is desirable that the angle θ formed between the side surface of the buffer layer and the main surface of the substrate is an acute angle even when the sealing body 300 is configured to include a single buffer layer.

  In the above-described embodiment, the case where the planar sizes of the plurality of buffer layers are different for each buffer layer has been described. However, the buffer layers may be formed to have the same size using the same mask.

  In the above-described embodiment, the bottom surface light emission method for extracting light from the array substrate side has been described as an example. However, the top surface light emission method for providing light transmission from the second electrode and the sealing body to extract light from the sealing body side. The present invention can also be applied to. At this time, it is desirable to provide the first electrode with light reflectivity or to provide a light reflection film in a layer separate from the light transmissive first electrode.

  Next, a method for manufacturing an organic EL display device will be described. Here, in order to simplify the description, a method for manufacturing an organic EL display device including the sealing body having the structure shown in FIG. 4 will be described.

  First, as shown in FIG. 7A, a substrate SUB having an effective portion 106 formed on the main surface is prepared. The effective unit 106 is formed by repeating processes such as formation and patterning of a metal film and an insulating film, and the pixel switch 10, the drive transistor 20, the storage capacitor element 30, the scanning line drive circuit 107, and the signal line drive circuit. In addition to 108, various wirings such as a signal line Xn, a scanning line Ym, and a power supply line P, and a plurality of pixels PX each including an organic EL element 40 are included.

Subsequently, the sealing body 300 is disposed so as to cover at least the effective portion 106 of the main surface of the substrate SUB.
The sealing body 300 is formed by, for example, a manufacturing apparatus 600 configured as shown in FIG. That is, the manufacturing apparatus 600 includes a first chamber 601 for forming a barrier layer, a second chamber 602 for forming a resin material for the buffer layer, and a first chamber for curing the formed resin material. Three chambers 603 are provided.

  In the first chamber 601, a metal material functioning as a barrier layer is deposited through a barrier layer mask having an opening with a predetermined shape. The barrier layer mask applied here may be installed in the first chamber 601 so as to be aligned in a predetermined positional relationship with the substrate SUB introduced with the effective portion 106 facing the vapor deposition source side. Alternatively, it may be mounted in a state in which the substrate SUB on which the effective portion 106 is formed is previously aligned in a predetermined positional relationship.

  In the second chamber 602, a liquid monomer of a resin material that functions as a buffer layer is evaporated and deposited through a buffer layer mask having an opening of a predetermined shape. As shown in FIG. 9, the second chamber 602 includes a buffer layer mask M between the material source S for forming the buffer layer and the main surface on which the effective portion 106 of the substrate SUB is formed. . By arranging the buffer layer mask M at a predetermined position, the arrival of the resin material scattered from the material source S to the main surface of the substrate SUB is restricted, and the resin material that has passed through the opening AP is formed on the main surface of the substrate SUB. The predetermined area AR is reached. That is, the resin material is deposited in the predetermined area AR.

  In the third chamber 603, the resin material is cured by polymerizing the deposited monomer. When a photosensitive resin material (for example, an ultraviolet curable resin material) is applied as a monomer, the third chamber 603 includes a light source having a predetermined wavelength (for example, an ultraviolet wavelength). In such a third chamber 603, the deposited monomer is exposed with a predetermined exposure amount, and the monomer is polymerized to be cured, thereby forming a buffer layer.

  Further, when an electron beam curable resin material is applied as the monomer, the third chamber 603 includes an electron beam source. In such a third chamber 603, by irradiating the deposited monomer with an electron beam, the monomer is polymerized to be cured and a buffer layer is formed.

  Here, in order to form the buffer layer, a second chamber 602 for film formation and a third chamber 603 for curing are prepared, but the second chamber 602 includes a light source or an electron beam source having a predetermined wavelength, The film forming process and the curing process may be performed simultaneously in the second chamber 602. Further, it is possible to eliminate the curing step (third chamber) by depositing a resin material that is polymerized in the gas phase in the second chamber 602.

  In the process of forming the sealing body 300, first, as shown in FIG. 7B, the first barrier layer 320 that shields the effective portion 106 from the outside air is formed on the main surface of the substrate SUB. That is, the substrate SUB having the effective portion 106 formed on the main surface is introduced into the first chamber 601. The first barrier layer 320 is formed by depositing a metal material through a mask in the first chamber 601. At this time, the first barrier layer 320 includes the effective portion 106 on the main surface of the substrate SUB and is formed over a larger range than the effective portion 106.

  Subsequently, as shown in FIG. 7C, a first buffer layer 311 having a pattern larger than at least the effective portion 106 is formed on the first barrier layer 320 corresponding to the effective portion 106. That is, the substrate SUB on which the first barrier layer 320 is formed is introduced into the second chamber 602. In the second chamber 602, for example, a liquid monomer of an ultraviolet curable resin material is evaporated as a resin material, and the monomer is formed in a predetermined area AR on the main surface of the substrate through the buffer layer mask M. The predetermined area AR is a range smaller than the first barrier layer 320 immediately below, and includes the effective portion 106 and is larger than the effective portion 106.

  Thereafter, the substrate SUB is introduced into the third chamber 603. In the third chamber 603, the monomer formed on the main surface of the substrate SUB is exposed with light having an ultraviolet wavelength with a predetermined exposure amount. Thereby, the monomer is polymerized and cured, and the first buffer layer 311 is formed.

  Subsequently, as shown in FIG. 7D, the first buffer layer 311 and the first barrier layer 320 are shielded from the outside air in the first chamber 601, similarly to the first barrier layer 320, on the main surface of the substrate SUB. Two barrier layers 321 are formed. The second barrier layer 321 is formed over a larger range than the first buffer layer 311 directly below.

  Subsequently, as illustrated in FIG. 7E, a second buffer layer 312 having a pattern larger than at least the effective portion 106 is formed on the second barrier layer 321 so as to correspond to the effective portion 106. That is, the substrate SUB on which the second barrier layer 321 is formed is introduced into the second chamber 602. In the second chamber 602, the liquid monomer of the ultraviolet curable resin material is evaporated, and the monomer is formed in the predetermined area AR of the substrate main surface through the buffer layer mask M. The predetermined area AR is a range smaller than the second barrier layer 321 immediately below, and includes the effective portion 106 and is larger than the effective portion 106.

  The monomer film formation conditions for forming the second buffer layer 312 are different from the monomer film formation conditions for forming the first buffer layer 311. For example, in the sealing body 300 having the structure shown in FIG. 4, the first buffer layer 311 formed first is thicker than the second buffer layer 321 formed later. For example, the first buffer layer 311 forms a monomer at a film formation rate of 200 Å / sec, while the second buffer layer 312 forms a monomer at a film formation rate of 1.3 Å / sec, for example. Then, a first buffer layer 311 having a thickness of 100 nm and a second buffer layer 312 having a thickness of 2 μm were formed. In this way, by controlling the film formation rate according to the film thickness, while maintaining the tact in the thick film buffer layer film formation for ensuring flatness, the dense film formation in the thin film buffer layer Can be performed.

  Thereafter, the substrate SUB is introduced into the third chamber 603. In the third chamber 603, the monomer formed on the main surface of the substrate SUB is exposed with light having an ultraviolet wavelength with a predetermined exposure amount. As a result, the monomer is polymerized and cured, and the second buffer layer 312 is formed.

  Subsequently, as shown in FIG. 7F, on the main surface of the substrate SUB, similarly to the first barrier layer 320, in the first chamber 601, the surfaces of the second buffer layer 312 and the second barrier layer 321 are shielded from the outside air. Three barrier layers 322 are formed. The third barrier layer 322 is formed over a larger range than the second buffer layer 312 immediately below. Through the steps as described above, a sealing body 300 having a structure as shown in FIG. 4 is formed.

  Subsequently, an adhesive is applied to the entire surface of the sealing body 300, that is, the entire surface of the second barrier layer 321, and the sealing member 200 is bonded. Further, if necessary, a polarizing plate may be attached to the surface on the side from which EL light emission is taken out.

  When a plurality of array portions are formed on the mother substrate, the mother substrate is cut out into a single size for each array portion thereafter. Thereby, the single array substrate 100 to which the sealing body 300 and the sealing member 200 are attached from the mother substrate SUB is formed. In addition, when a single array portion is formed on a substrate without using a mother substrate, there is no need to cut out to a single size. In this case, the sealing body 300 and the sealing member are formed using the substrate SUB. A single array substrate 100 to which 200 is attached is directly formed.

  According to the organic EL display device 1 manufactured by the manufacturing process as described above, it is possible to reliably cover the organic EL element 40 formed on the effective portion 106 which is not easily affected by the lower layer. In addition, even if a minute gap is formed in either of these buffer layers or barrier layers, by laminating a plurality of layers, the route to reach the organic EL element 40 becomes longer, and the lifetime is increased. There is enough effect. Therefore, the organic EL element 40 can be shielded from the outside air, and sufficient performance can be maintained over a long period of time. Further, when the sealing member 200 is adhered to the sealing body 300 with an adhesive or when the polarizing plate is adhered to the sealing member 200 with an adhesive, the organic EL element 40 containing impurities contained in the adhesive is used. Intrusion into the inside can be prevented, and deterioration of the performance of the organic EL element 40 can be prevented.

  In the sealing body 300 including a plurality of buffer layers, at least one buffer layer is formed to have a film thickness different from that of the other buffer layers 312. Each of such buffer layers can be formed by setting different film formation conditions in each film formation step of forming a resin material.

  Further, the angle formed between the side surface of each buffer layer constituting the sealing body 300 and the main surface of the substrate depends on the film forming rate in the resin material film forming process in the second chamber 602, and the mask and substrate main surface for forming the buffer layer. Control is possible by appropriately setting the distance between the surface and the like.

  For example, in the second chamber as shown in FIG. 9, the buffer layer mask M is configured to be movable in the normal direction of the substrate SUB while being parallel to the main surface of the substrate SUB. When the gap G with the layer mask M is widened, it may be used that the pattern formed on the main surface of the substrate SUB is wider than the opening AP of the buffer layer mask M.

  In addition, the second chamber as shown in FIG. 10 includes at least one buffer layer mask M, and the opening AP of the buffer layer mask M is a side surface whose side closer to the substrate SUB is wider than the deposition source side. Defined by MS. The side surface MS and the substrate SUB are formed by evaporating a resin material in a state where the buffer layer mask M having such an opening AP is disposed close to (or in close contact with) the main surface of the substrate SUB. The angle formed between the side surface of the buffer layer and the main surface of the substrate can be controlled in accordance with the angle.

  Further, the second chamber as shown in FIG. 11 includes a plurality of buffer layer masks M1, M2, M3..., And is arranged close to (or in close contact with) the main surface of the substrate SUB. M1 has an opening AP1 having a larger area than the others, the buffer layer mask M2 has an opening AP2 having an area smaller than the opening AP1, and the buffer layer mask M3 has an opening AP3 having an area smaller than the opening AP2. have. By laminating a plurality of such buffer layer masks M1, M2, M3,..., It is possible to define an opening AP whose side closer to the substrate SUB is wider than the evaporation source side. By vapor deposition, the angle formed between the side surface of the buffer layer and the main surface of the substrate can be controlled.

  As described above, according to this embodiment, the substantially rectangular effective portion having a plurality of pixels formed on the main surface of the substrate for displaying an image and at least the effective portion of the main surface of the substrate are covered. An optical device is provided. In this optical device, the sealing body has a structure in which at least two buffer layers and a barrier layer that covers each buffer layer are stacked in a pattern larger than the buffer layer. In addition, at least one buffer layer has a thickness different from that of the other buffer layers.

  Thus, by forming at least one buffer layer constituting the sealing body so as to have a relatively thick film thickness, the unevenness of the effective portion can be sufficiently absorbed, and the buffer layer is substantially flat. It becomes possible to arrange | position a barrier layer on the formed surface. For this reason, generation | occurrence | production of the defect in the barrier layer which covers a buffer layer can be suppressed, and generation | occurrence | production of a coverage defect can be prevented. For this reason, the sealing performance as a sealing body can be improved. Therefore, high shielding properties against external impurities and outside air can be secured, and good display performance can be maintained over a long period of time.

  Further, by forming a single buffer layer thick and forming another buffer thin, it is possible to reduce the thickness of the entire device and improve productivity.

  Further, in this optical device, the sealing body has a structure in which a buffer layer and a barrier layer covering each buffer layer are stacked in a pattern larger than the buffer layer. In addition, the angle formed between the side surface of the buffer layer and the main surface of the substrate is an acute angle. Thereby, the barrier layer covering the buffer layer is disposed along the side surface of the buffer layer, and the occurrence of defects such as pinholes can be prevented. For this reason, the penetration | invasion in an organic EL element, such as a water | moisture content and oxygen, can be prevented, and deterioration of an organic EL element can be suppressed. Therefore, good display performance can be maintained over a long period of time.

  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. In addition, various inventions can be formed by appropriately combining a plurality of components 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 case where the buffer layer constituting the sealing body is two layers and the barrier layer is three layers has been described as an example (FIGS. 4 and 5). It is not limited. In the case where the sealing body is formed by laminating ten or more thin films, the number of steps is too large and the productivity is lowered. For this reason, the number of thin film layers to be laminated is 2 or more and less than 10 layers, and preferably 3 to 5 layers.

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 cross-sectional view schematically showing a pixel structure of the organic EL display device shown in FIG. FIG. 3 is a perspective view schematically showing the appearance of the array substrate on which the sealing body is arranged. FIG. 4 is a diagram schematically showing a cross-sectional structure of the array substrate and the sealing body when the array substrate shown in FIG. 3 is cut along line AB. FIG. 5 schematically shows a cross-sectional structure of another sealing body when the array substrate shown in FIG. 3 is cut along line AB. FIG. 6 is a diagram schematically showing a cross-sectional structure of another sealing body when the array substrate shown in FIG. 3 is cut along line AB. FIG. 7A is a schematic cross-sectional view for explaining the method for manufacturing the organic EL display device. FIG. 7B is a schematic cross-sectional view for explaining the method for manufacturing the first barrier layer of the sealing body applied to the organic EL display device. FIG. 7C is a schematic cross-sectional view for explaining the method for manufacturing the first buffer layer of the sealing body applied to the organic EL display device. FIG. 7D is a schematic cross-sectional view for explaining the method for manufacturing the second barrier layer of the sealing body applied to the organic EL display device. FIG. 7E is a schematic cross-sectional view for explaining the method for manufacturing the second buffer layer of the sealing body applied to the organic EL display device. FIG. 7F is a schematic cross-sectional view for explaining the method for manufacturing the third barrier layer of the sealing body applied to the organic EL display device. FIG. 8 is a diagram schematically showing a configuration of a manufacturing apparatus for forming a sealing body. FIG. 9 is a diagram schematically showing the configuration of the second chamber in the manufacturing apparatus shown in FIG. FIG. 10 schematically shows another configuration of the second chamber in the manufacturing apparatus shown in FIG. FIG. 11 is a diagram schematically showing another configuration of the second chamber in the manufacturing apparatus 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 DESCRIPTION OF SYMBOLS 100 ... Array substrate 106 ... Effective part 120 ... Wiring board 200 ... Sealing member 300 ... Sealing body 311 ... First buffer layer 312 ... Second buffer layer 320 ... First barrier layer 321 ... second barrier layer, 322 ... third barrier layer, PX ... pixel, M ... buffer layer mask, B ... buffer layer mask

Claims (10)

A display element formed on a substrate main surface,
A sealing body arranged to cover the display element;
The sealing body has a structure in which at least two buffer layers and a barrier layer that is a pattern larger than the buffer layer and covers each buffer layer are laminated,
At least one buffer layer has a film thickness different from that of other buffer layers. An effective portion formed on the main surface of the substrate and provided with a plurality of display elements;
A sealing body disposed so as to cover at least the effective portion of the main surface of the substrate,
The sealing body has a structure in which at least two buffer layers and a barrier layer that is a pattern larger than the buffer layer and covers each buffer layer are laminated,
The optical device, wherein at least one buffer layer has a film thickness different from that of other buffer layers.   3. The optical device according to claim 2, wherein a film thickness of the first buffer layer disposed closest to the effective portion is larger than a second buffer layer disposed on an upper layer of the first buffer layer.   3. The optical device according to claim 2, wherein the first buffer layer disposed closest to the effective portion has a thickness smaller than that of the second buffer layer disposed on the first buffer layer. A display element formed on a substrate main surface,
A sealing body arranged to cover the display element;
The sealing body has a structure in which a buffer layer and a barrier layer that is a pattern larger than the buffer layer and covers the buffer layer are laminated,
An angle formed between the side surface of the buffer layer and the main surface of the substrate is an acute angle. An effective portion formed on the main surface of the substrate and provided with a plurality of display elements;
A sealing body disposed so as to cover at least the effective portion of the main surface of the substrate,
The sealing body has a structure in which a buffer layer and a barrier layer that is a pattern larger than the buffer layer and covers the buffer layer are laminated,
An optical device characterized in that an angle formed between the side surface of the buffer layer and the main surface of the substrate is an acute angle.   The optical device according to claim 6, wherein an angle formed between the side surface of the buffer layer and the main surface of the substrate is 60 degrees or less.   The effective portion includes a first electrode arranged in a matrix and formed in an independent island shape for each pixel, a second electrode arranged opposite to the first electrode and formed in common to all pixels, and the first electrode The optical device according to claim 2, further comprising: an organic active layer held between one electrode and the second electrode.   The optical device according to claim 2, wherein the barrier layer is formed of a metal material, a metal oxide material, or a ceramic material.   The optical device according to claim 2, wherein the buffer layer is made of a resin material.

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