Patent Application
20240196714
The present disclosure relates to a display device and an electronic apparatus using the display device.
As a display device using an organic electroluminescence (EL) element, a display device having a structure in which an organic layer including at least an organic light emitting layer and a first cathode electrode are laminated on an anode electrode formed separately for each pixel has been proposed. At this time, one pixel may include a plurality of sub-pixels such as RGB.
Patent Document 1 proposes an organic light emitting device in which an upper electrode includes a first upper electrode and a second upper electrode directly provided on the first upper electrode.
The technique disclosed in Patent Document 1 has room for improvement in terms of suppressing damage to an organic light emitting layer due to a gas or the like at the time of processing and improving the reliability of a light emitting state of a pixel.
The present disclosure has been made in view of the above-described points, and an object of the present disclosure is to provide a display device and an electronic apparatus capable of improving the reliability of a light emission state of a pixel.
The present disclosure is, for example, (1) a display device including:
Furthermore, the present disclosure may be, for example, (2) an electronic apparatus including a display device according to (1) described above.
Hereinafter, an implementation example and the like according to the present disclosure will be described with reference to the drawings. Note that, the description will be made in the following order. In the present specification and the drawings, configurations having substantially the same functional configuration are denoted by the same reference signs, and redundant descriptions are omitted.
Note that, the description will be given in the following order.
The following description is preferred specific examples of the present disclosure, and the content of the present disclosure is not limited to these embodiments and the like. Furthermore, in the following description, directions of front and back, left and right, up and down, and the like are indicated in consideration of convenience of description, but the content of the present disclosure is not limited to these directions. In the examples of
The display device 10A is a top emission display device. In the display device 10A, the drive substrate 11 is located on a back surface side of the display device 10A, and a direction from the drive substrate 11 toward the light emitting elements 13 (+Z direction) is a front surface side (display surface 110A side, upper surface side) direction of the display device 10A. In the following description, in each layer constituting the display device 10A, a surface on the display surface 110A side of the display device 10A is referred to as a first surface (upper surface), and a surface on the back surface side of the display device 10A is referred to as a second surface (lower surface). Note that, in the example of the drawing, a peripheral portion 110B is provided on the drive substrate 11 at the peripheral edge of the region of the display surface 110A.
The display device 10A is, for example, a microdisplay in which self-emitting elements such as an organic light emitting diode (OLED), a micro-OLED, or a micro-LED are formed in an array. The display device 10A can be suitably mounted on a display device for virtual reality (VR), mixed reality (MR), or augmented reality (AR), an electronic view finder (EVF), a small projector, or the like. This similarly applies to the second to sixth embodiments.
In the example of the display device 10A illustrated in
Furthermore, the sub-pixels 101R, 101G, and 101B are arranged in the region of the display surface 110A. In the example of
In the following description, in a case where the sub-pixels 101R, 101G, and 101B are not particularly distinguished, the sub-pixels 101R, 101G, and 101B are collectively referred to as the sub-pixel 101.
The drive substrate 11 is provided with various circuits for driving the plurality of light emitting elements 13 on a substrate 11A. Examples of the various circuits include a drive circuit that controls driving of the light emitting elements 13 and a power supply circuit (none of which are illustrated) that supplies power to the plurality of light emitting elements 13.
The substrate 11A may include, for example, glass or resin having low moisture and oxygen permeability, or may include a semiconductor in which a transistor or the like is easily formed. Specifically, the substrate 11A may be a glass substrate, a semiconductor substrate, a resin substrate, or the like. The glass substrate includes, for example, high strain point glass, soda glass, borosilicate glass, forsterite, lead glass, quartz glass, or the like. The semiconductor substrate includes, for example, amorphous silicon, polycrystalline silicon, monocrystalline silicon, or the like. The resin substrate includes, for example, at least one selected from a group including polymethyl methacrylate, polyvinyl alcohol, polyvinyl phenol, polyethersulfone, polyimide, polycarbonate, polyethylene terephthalate, polyethylene naphthalate, and the like.
A plurality of contact plugs (not illustrated) for connecting the light emitting elements 13 and the various circuits provided on the substrate 11A is provided on the first surface of the drive substrate 11.
In the display device 10A, the plurality of light emitting elements 13 is provided on the first surface of the drive substrate 11. The light emitting elements 13 are provided for each sub-pixel 101. In the example of
In the present specification, in a case where the types such as the light emitting elements 13R, 13G, and 13B are not particularly distinguished, the light emitting elements 13R, 13G, and 13B are collectively referred to as the light emitting elements 13. The plurality of light emitting elements 13 is, for example, two-dimensionally arranged in a prescribed arrangement pattern such as a matrix shape or the like. In the example of
Each of the light emitting elements 13 includes an anode electrode 130, an organic layer 131, and a first cathode electrode 132. The anode electrode 130, the organic layer 131, and the first cathode electrode 132 are provided in this order in a direction away from the drive substrate 11 side (along the +Z direction). In the example of
In the present specification, as illustrated in
In the display device 10A, a plurality of the anode electrodes 130 is provided on the first surface side of the drive substrate 11 in a state of being electrically separated for each sub-pixel 101. In the example of
The anode electrode 130 includes at least one of a metal layer or a metal oxide layer. For example, the anode electrode 130 may be constituted by a single-layer film of a metal layer or a metal oxide layer, or a laminated film of a metal layer and a metal oxide layer. In a case where the anode electrode 130 is constituted by a laminated film, the metal oxide layer may be provided on the organic layer 131 side, or the metal layer may be provided on the organic layer 131 side, but from the viewpoint of adjoining a layer having a high work function to the organic layer 131, the metal oxide layer is preferably provided on the organic layer 131 side.
The metal layer includes, for example, at least one metal element selected from a group including chromium (Cr), gold (Au), platinum (Pt), nickel (Ni), copper (Cu), molybdenum (Mo), titanium (Ti), tantalum (Ta), aluminum (Al), magnesium (Mg), iron (Fe), tungsten (W), and silver (Ag). The metal layer may include the at least one metal element described above as a constituent element of an alloy. Specific examples of the alloy include an aluminum alloy and a silver alloy. Specific examples of the aluminum alloy include, for example, AlNd and AlCu.
The metal oxide layer includes, for example, at least one of a mixture of indium oxide and tin oxide (ITO), a mixture of indium oxide and zinc oxide (IZO), or titanium oxide (TiO).
The organic layer 131 is provided between the anode electrode 130 and the first cathode electrode 132. The organic layer 131 is provided in a state of being electrically separated (divided) for each sub-pixel 101. In the example of the drawing, the organic layers 131R, 131G, and 131B are provided. The organic layers 131R, 131G, and 131B have color types corresponding to a light emission color of the sub-pixel 101, and red, blue, and green are set as emission colors, respectively.
The organic layer 131 has a configuration in which a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer are laminated in this order from the anode electrode 130 toward the first cathode electrode 132. Note that the configuration of the organic layer 131 is not limited thereto, and layers other than the light emitting layer are provided as necessary. The light emitting layer is an organic light emitting layer containing an organic light emitting material.
The hole injection layer is a buffer layer for enhancing hole injection efficiency into the light emitting layer and reducing leakage. The hole transport layer is for enhancing hole transport efficiency to the light emitting layer. The light emitting layer generates light by recombination of electrons and holes when an electric field is applied. The electron transport layer is for enhancing electron transport efficiency to the light emitting layer. An electron injection layer may be provided between the electron transport layer and the first cathode electrode 132. The electron injection layer is for enhancing electron injection efficiency.
Note that a thickness of the organic layer 131 may be the same or may be different between different color types of the sub-pixel 101. For example, the thicknesses of the organic layers 131R, 131G, and 131B corresponding to the sub-pixels 101R, 101G, and 101B may be different from each other. In the example of
The first cathode electrode 132 is provided to face the anode electrode 130. The first cathode electrode 132 faces the second cathode electrode 134. The first cathode electrode 132 is electrically separated for each of the sub-pixels 101R, 101G, and 101B.
The first cathode electrode 132 is a transparent electrode having transparency to light generated in the organic layer 131. Here, in the present specification, unless otherwise specified, the concept of the transparent electrode includes not only a transparent conductive layer but also a semi-transmissive reflecting layer and a combination thereof. The first cathode electrode 132 includes at least one of a metal layer or a metal oxide layer. More specifically, the first cathode electrode 132 is constituted by a single-layer film of a metal layer or a metal oxide layer, or a laminated film of a metal layer and a metal oxide layer. In a case where the first cathode electrode 132 is constituted by a laminated film, the metal layer may be provided on the organic layer 131 side, or the metal oxide layer may be provided on the organic layer 131 side, but from the viewpoint of adjoining a layer having a low work function to the organic layer 131, the metal layer is preferably provided on the organic layer 131 side.
The metal layer includes, for example, at least one metal element selected from a group including magnesium (Mg), aluminum (Al), silver (Ag), calcium (Ca), and sodium (Na). The metal layer may include the at least one metal element described above as a constituent element of an alloy. Specific examples of the alloy include an MgAg alloy, an MgAl alloy, an AlLi alloy, and the like. The metal oxide includes, for example, at least one of a mixture of indium oxide and tin oxide (ITO), a mixture of indium oxide and zinc oxide (IZO), or zinc oxide (ZnO).
The second cathode electrode 134 is provided as an electrode common to all the sub-pixels 101R, 101G, and 101B in a region in the display surface 110A. The second cathode electrode 134 is connected to the first cathode electrode 132 separated for each sub-pixel 101 via a connection portion 18 as described later. The second cathode electrode 134 is provided on a lower protective layer 17 as described later. In the example of
Similarly to the first cathode electrode 132, the second cathode electrode 134 is a transparent electrode having transparency to light generated in the organic layer 131. Furthermore, similarly to the first cathode electrode 132, the second cathode electrode 134 includes at least one of a metal layer or a metal oxide layer. The metal layer and the metal oxide layer applicable to the second cathode electrode 134 are similar to the metal layer and the metal oxide layer applicable to the first cathode electrode 132.
In the display device 10A, as illustrated in
The insulating layer 14 includes, for example, an organic material or an inorganic material. The organic material includes, for example, at least one of polyimide or acrylic resin. The inorganic material includes, for example, at least one of silicon oxide, silicon nitride, silicon oxynitride, or aluminum oxide.
The lower protective layer 17 is a protective layer formed below the second cathode electrode 134 (on a second surface side of the second cathode electrode 134), and protects the first cathode electrode 132 and the organic layer 131. In the example of
In the present specification, as necessary, the term lower protective layer 17 is used as a concept including the element protective layer 15 as a protective layer and the side wall protective layer 16 as a protective layer.
The element protective layer 15 is formed as a protective layer on the first surface of each of the first cathode electrodes 132, and covers the first surface of the first cathode electrode 132. The element protective layer 15 may entirely cover the first cathode electrode 132 or may be in a state of avoiding a partial region of the first cathode electrode 132. The element protective layer 15 is located above the light emitting element 13 and is interposed between the first cathode electrode 132 and the second cathode electrode 134. The element protective layer 15 shields the light emitting element 13 from the outside air, and suppresses moisture ingress into the light emitting element 13 from the external environment. The element protective layer 15 prevents the organic layer 131 from being damaged by being exposed to a process gas, a chemical liquid, or the like in a manufacturing process. Furthermore, in a case where the first cathode electrode 132 includes a metal layer, the element protective layer 15 may have a function of suppressing oxidation of the metal layer.
The element protective layer 15 includes an insulating material. As the insulating material, for example, thermosetting resin or the like can be used. In addition, the insulating material may be SiO, SiON, AlO, TiO, or the like. In this case, as the element protective layer 15, a CVD film containing SiO, SiON, or the like, an ALD film containing AlO, TiO, SiO, or the like, or the like can be exemplified. The element protective layer 15 may be formed as a single layer, or may be formed in a state where a plurality of layers is laminated. In a case where the element protective layer 15 includes a first protective layer in the first cathode electrode 132 and a second protective layer so as to cover the first protective layer as a two-layer laminated structure, the first protective layer preferably includes a CVD film, and the second protective layer preferably includes an ALD film. Note that the CVD film indicates a film formed using chemical vapor deposition. The ALD film indicates a film formed using atomic layer deposition.
The shape of the element protective layer 15 in the up-down direction (thickness direction) is not particularly limited, and the side wall of the element protective layer 15 may be tapered, or may be formed in a non-tapered shape as illustrated in
In a case where the normal direction of the display surface 110A is the line-of-sight direction, the element protective layer 15 has a shape corresponding to the shape of the light emitting element 13, and it is preferable to cover the light emitting surface of the light emitting element 13 from the viewpoint of efficiently exhibiting the function of protecting the light emitting element 13 and from the viewpoint of forming the connection portion 18 to be described later at an appropriate position.
Note that the thickness of the element protective layer 15 may be the same or different among different color types of the sub-pixel 101. For example, in a case where the thicknesses of the organic layers 131R, 131G, and 131B corresponding to the sub-pixels 101R, 101G, and 101B are different from each other, the first surface for forming the second cathode electrode 134 can be flattened by making the thickness of the element protective layer 15 different.
In the example of
The upper protective layer 19 is a protective layer covering the second cathode electrode 134. The upper protective layer 19 protects the second cathode electrode 134. Specifically, the upper protective layer 19 suppresses moisture from reaching the second cathode electrode 134 from the external environment. Moreover, similarly to the lower protective layer 17, the upper protective layer 19 also suppresses moisture ingress into the light emitting element 13 from the external environment. That is, the upper protective layer 19 reinforces the protection of the light emitting element 13 by the lower protective layer 17. In a case where the second cathode electrode 134 includes a metal layer, the upper protective layer 19 may have a function of suppressing oxidation of the metal layer.
The material of the upper protective layer 19 includes an insulating material similarly to the lower protective layer 17 such as the element protective layer 15. The kind of the insulating material may be similar to that described in the element protective layer 15. Similarly to the element protective layer 15, the upper protective layer 19 may also be formed as a single layer or in a state where a plurality of layers is laminated.
The connection portion 18 is a portion that electrically connects the first cathode electrode 132 and the second cathode electrode 134. In the display device 10A according to the first embodiment, the connection portion 18 is provided separately from the first cathode electrode 132 and the second cathode electrode 134. However, the application range of the connection portion 18 is not limited to the technology of providing the connection portion separately from the first cathode electrode 132 and the second cathode electrode 134, and the connection portion 18 can be applied to a technology in which a part of the first cathode electrode 132 or a part of the second cathode electrode 134 is used as a portion connecting the first cathode electrode 132 and the second cathode electrode 134.
The connection portion 18 is formed along the side wall of the element protective layer 15. The connection portion 18 may be formed along a part of the surface of the side wall 15A of the element protective layer 15, but is preferably formed on the entire circumference of the side wall 15A of the element protective layer 15 as illustrated in
Furthermore, in a case where the element protective layer 15 covers the light emitting region P, the connection portion 18 is provided outside the light emitting region P, and the influence of the connection portion 18 on the light emitting state is suppressed. Therefore, it is possible to suppress a decrease in luminance of the display device 10A.
The proximal end 18A of the connection portion 18 is a position where the side wall 15A of the element protective layer 15 is in contact with the first cathode electrode 132, and the connection portion 18 extends from the proximal end 18A toward the second cathode electrode 134 along the side wall 15A of the element protective layer 15. The distal end 18B of the connection portion 18 is in contact with the second surface side of the second cathode electrode 134.
The connection portion 18 contains a conductive material. The connection portion 18 preferably includes a product of the first cathode electrode 132 (so-called depot) from the viewpoint of simplifying the process. In this case, the connection portion 18 contains an element (metal element) that forms the first cathode electrode 132, contains a conductive material, and has conductivity. Furthermore, the connection portion 18 may be newly provided by a sidewall process. The sidewall process refers to a technique of forming a layer on a side wall surface or the like by appropriately combining a lithography technique, a CVD technique, an etching technique, and the like.
A filling resin layer 20 may be formed on the first surface side of the upper protective layer 19. The filling resin layer 20 can have a function as an adhesive layer for bonding a counter substrate 21 described later. Examples of the filling resin layer 20 include ultraviolet curable resin, thermosetting resin, and the like.
The counter substrate 21 is provided on the filling resin layer 20 in a state of facing the drive substrate 11. The counter substrate 21 seals the light emitting elements 13 together with the filling resin layer 20. The counter substrate 21 may include a similar material to the substrate 11A included in the drive substrate 11, and preferably includes a material such as glass or the like.
Note that, for convenience of description, description of the filling resin layer 20 and the counter substrate 21 is omitted in
A method of manufacturing the display device 10A according to the first embodiment will be described with reference to
According to the first embodiment, since the connection portion 18 can have a self-alignment structure at a position along the side wall 15A of the element protective layer 15, the via opening process can be omitted. Furthermore, since the connection between the second cathode electrode 134 and the first cathode electrode 132 can be realized without securing a region having a certain size inside the sub-pixel 101 for the purpose of securing the connection portion, it is advantageous for high definition of the sub-pixel 101.
Furthermore, in the display device 10A, the element protective layer 15 is provided between the first cathode electrode 132 and the second cathode electrode 134. As a result, the element protective layer 15 can prevent the organic layer 131 from being exposed to a process gas, a chemical liquid, or the like in an etching process or the like of the organic layer 131 and the first cathode electrode 132. That is, the organic layer 131 can be prevented from being damaged. Therefore, it is possible to suppress a decrease in reliability of the light emission state of the display device 10A.
Furthermore, the anode electrode 130, the organic layer 131, and the first cathode electrode 132 are separated for each sub-pixel 101, and the insulating side wall protective layer 16 is provided between the sub-pixels 101. As a result, a leakage current between the adjacent sub-pixels 101 can be suppressed. Therefore, color mixing can be suppressed, and color reproducibility and light emission efficiency can be improved, so that the reliability of the light emission state of the display device 10A can be improved.
Next, a modification example of the display device 10A according to the first embodiment will be described.
In the description of the first embodiment, the light emission color of the organic layer 131 is the color type corresponding to the light emission color of the sub-pixel 101, but in the display device 10A according to the first embodiment, the light emission color of the light emitting element 13 may be a color type other than the color type corresponding to the light emission color of the sub-pixel 101. For example, specifically, the light emitting element 13W in which the light emission color is white regardless of the color type of the sub-pixel 101 may be provided (
The light emitting element 13W includes an organic layer 131 W that emits white light. The structure of the organic layer 131W is not particularly limited to the above, and examples thereof include a light emitting layer having a so-called 1 stack structure having a combination of a red light emitting layer, a green light emitting layer, and a blue light emitting layer. Note that the thickness of the organic layer 131W may be the same or different for each sub-pixel 101. In the example of
The color filter 23 is provided on the first surface side (upper side, +Z direction side) of the upper protective layer 19. Furthermore, the color filter 23 illustrated in
In the display device 10A of the first embodiment, the layout of the sub-pixels 101R, 101G, and 101B may be a pattern other than the stripe-shaped pattern as illustrated in the example of
In the display device 10A of the first embodiment, as illustrated in
In the third modification example, the resonator structure 24 includes the second cathode electrode 134 and the light emitting element 13. The resonator structure 24 shows a structure that causes light of a predetermined wavelength to resonate. In the third modification example, for example, it is preferable that the first cathode electrode 132 of the light emitting element 13 includes a transparent electrode, and the second cathode electrode 134 includes a semi-transmission reflection layer. Note that the case that the semi-transmission reflection layer is included includes the case that only the semi-transmission reflection layer is formed. The anode electrode 130 preferably has light reflectivity. The optical distance between the second cathode electrode 134 and the anode electrode 130 is adjusted such that the resonator structure 24 resonates light corresponding to the color type of the sub-pixel 101 for each sub-pixel 101. This is specifically realized, for example, by adjusting the thickness of the element protective layer 15 as illustrated in
According to the display device 10A, even if the element protective layer 15 has different thicknesses as described above, the connection portion 18 is formed on the side wall 15A of the element protective layer 15, so that the first cathode electrode 132 and the second cathode electrode 134 can be effectively connected by the connection portion 18.
As illustrated in
In the display device 10A of the first embodiment, as illustrated in
In the display device 10A of the first embodiment, as illustrated in
A display device 10B according to a second embodiment will be described. As illustrated in
Furthermore, the display device 10B is provided with an upper protective layer 19, a filling resin layer 20, a counter substrate 21, and a color filter 23 as necessary. Since these configurations are similar to those of the display device 10A according to the first embodiment, description and illustration thereof are omitted. This similarly applies to the third to sixth embodiments as long as these omissions are not particularly described in the modification examples and the like.
In the description of the first embodiment, the sub-pixel 101, the organic layer 131, and the like are collectively described in a case where color types are not particularly distinguished, but this similarly applies to the second to sixth embodiments.
In the second embodiment and third to sixth embodiments as described later, configurations different from those of the first embodiment will be described.
The display device 10B according to the second embodiment includes a lower protective layer 17 as a protective layer similarly to the display device 10A according to the first embodiment. In the example of
As illustrated in
As illustrated in
In the connection portion 30 illustrated in the example of
The position where the connection portion 30 is formed is not particularly limited, but is preferably formed on the position of the outer periphery 141 of the opening 14A in a case where the Z-axis direction (thickness direction of the light emitting element 13) is defined as the line-of-sight direction. In this case, it is possible to suppress the connection portion 30 from being arranged at a position entering the light emitting region P of the light emitting element 13. The outer periphery 141 of the opening 14A indicates a region in a predetermined outer range from the opening end edge 140.
In this regard, according to the display device 10B according to the second embodiment, since the inner portion 30B of the connection portion 30 is a portion having a refractive index lower than the refractive index of the lower protective layer 17 (element protective layer 15), the connection portion 30 can totally reflect light emitted from the organic layer 131 in an oblique direction, leakage of light to the adjacent sub-pixel 101 can be reduced, and utilization efficiency of light can be enhanced.
Furthermore, the connection portion 30 is provided so as to surround the periphery of the light emitting region P. As a result, as a connection structure between the first cathode electrode 132 and the second cathode electrode 134, an equivalent structure is formed at any position surrounding the light emitting surface (an equivalent structure is formed in all directions), variations in viewing angle characteristics can be suppressed, and the reliability of the light emitting state of the display device 10B can be improved.
According to the display device 10B according to the second embodiment, the first cathode electrode 132 and the organic layer 131 are covered with the lower protective layer 17 such as the element protective layer 15, and it is possible to suppress deterioration of the organic layer 131 at the time of forming the second cathode electrode 134.
Next, a modification example of the display device 10B according to the second embodiment will be described.
In the display device 10B according to the second embodiment, as illustrated in
In such a display device 10B according to the first modification example of the second embodiment, in the plurality of arranged connection portions 30, the member forming the side wall protective layer 16 and the inner portion 30B of the connection portion 30 are periodically and repeatedly arranged in the direction from the center of the element protective layer 15 toward the outside at a cycle shorter than the peak wavelength of the emission light. Therefore, in the display device 10B, since a portion in which the refractive index periodically changes at the wavelength level of the emission light is formed around the light emitting surface of the light emitting element 13 for each sub-pixel 101, the emission light in the oblique direction hardly leaks out from the position of the connection portion 30.
In the display device 10B according to the second embodiment, the inner portion 30B of the connection portion 30 is formed so as to surround the light emitting region P in a continuous space portion, but the connection portion 30 is not limited thereto. For example, the connection portion 30 may include vias 31 formed in the lower protective layer 17 as illustrated in
In the second modification example of the second embodiment, the element protective layer 15 and the side wall protective layer 16 are connected (continuous) between the adjacent vias 31, and in the example of
In the present specification, the via 31 is assumed to be a porous structure having conductivity. The via 31 shown in the second modification example of the second embodiment has a hole-like structure extending from the second cathode electrode 134 side to the first cathode electrode 132. The via 31 has a structure in which the second cathode electrode 134 is extended along the inner peripheral surface and the bottom surface (first surface of the first cathode electrode 132) of the hole formed in the lower protective layer 17. Therefore, in a case where the connection portion 30 is formed by the via 31, the outer peripheral portion 30A is formed by the second cathode electrode 134. The inside of the via 31 forming the inner portion 30B of the connection portion 30 is a portion having a refractive index lower than the refractive index of the lower protective layer 17. Specifically, in the example of
The plurality of vias 31 is arranged so as to surround the light emitting region P of the light emitting element 13, and form a via column 32. The connection portion 30 includes via columns 32.
According to the display device 10B according to the second modification example of the second embodiment, the via 31 to be the connection portion 30 is provided so as to surround the periphery of the light emitting surface of the light emitting element 13, whereby the via column 32 is formed. As a result, an equivalent structure is formed at any position surrounding the light emitting surface (an equivalent structure is formed in all directions), and variations in viewing angle characteristics can be suppressed.
Furthermore, in the display device 10B, since the via column 32 is formed, even if disconnection occurs in the predetermined via 31 or a contact failure occurs between a part of the via 31 and the first cathode electrode 132, the connection between the first cathode electrode 132 and the second cathode electrode 134 can be secured in the other via 31, and the reliability of the display device 10B can be improved.
In the display device 10B according to the second modification example of the second embodiment, a plurality of via columns 32 forming the connection portion 30 may be arranged at intervals in a direction from the center of each sub-pixel 101 toward the outside (direction away from the light emitting element 13) with the Z-axis direction as the line-of-sight direction (the third modification example).
In the third modification example of the second embodiment, the interval Wp1 between the adjacent connection portions 30 (the interval between the adjacent via columns 32) is preferably set to a value that is equal to or less than the peak wavelength of the emission light of the light emitting element 13 for each sub-pixel 101, and more preferably set to a value that is ½ or less of the peak wavelength.
For each of the light emitting elements 13 constituting the plurality of light emitting elements 13, the pitch of the plurality of vias surrounding the light emitting region P of each of the light emitting elements 13 is preferably smaller than the peak wavelength corresponding to the light emitted from each of the light emitting elements 13. That is, as a specific example, in the light emitting element 13R among the light emitting elements 13R, 13G, and 13B, for example, the pitch of the vias 31 arranged around the light emitting region P of the light emitting element 13R is preferably smaller than the peak wavelength of the red light which is the emission light from the light emitting element 13R. In the via column 32, the interval Wp2 (pitch) between the adjacent vias 31 is preferably set to a value that is equal to or less than the peak wavelength of the emission light of the light emitting element 13 for each sub-pixel 101, and more preferably set to a value that is equal to or less than ½ of the peak wavelength. Furthermore, the width of the space portion formed inside each via 31 is preferably equal to or less than the peak wavelength, and more preferably equal to or less than ½ of the peak wavelength.
The peak wavelength of the emission light of the light emitting element 13 varies depending on the color type of the sub-pixel 101. In view of this point, in a case where the display device 10B includes the plurality of sub-pixels 101 corresponding to the plurality of color types, and the connection portion 30 is provided for each sub-pixel 101, it is preferable that the pitch of the adjacent vias 31 forming the via column 32 be different according to the color type of the sub-pixel 101.
In such a display device 10B according to the third modification example of the second embodiment, the connection portion 30 is configured such that the vias 31 and the material forming the lower protective layer 17 are periodically and repeatedly arranged in a period smaller than the peak wavelength of the emission light in both the alignment direction of the vias 31 in the via column 32 and the arrangement direction of the plurality of via columns 32. In this case, in the display device 10B, since a portion in which the refractive index periodically changes at the wavelength level of the emission light is formed around the light emitting region P of the light emitting element 13 for each sub-pixel 101, the emission light in the oblique direction hardly leaks out from the position of the connection portion 30. Therefore, according to the display device 10B according to the third modification example of the second embodiment, light leakage can be more effectively suppressed, and light utilization efficiency can be improved.
In the display device 10B according to the second embodiment, the connection portion 30 is not limited to the case of being connected to the outer peripheral end portion 132A of the upper surface of the first cathode electrode 132, and may be connected at the position of the side wall 132B of the first cathode electrode 132.
A display device 10C according to a third embodiment will be described. In the display device 10C according to the third embodiment, as illustrated in
Furthermore, in the display device 10C according to the third embodiment, as illustrated in
In the example of
The second refractive index portion 34 has a refractive index lower than that of the first refractive index portion 33. The second refractive index portion 34 is preferably a space portion. The space portion may be a portion filled with air, rare gas, or the like, but is preferably a vacuum portion from the viewpoint of lowering the refractive index of the second refractive index portion 34. The second refractive index portion 34 is formed in a space extending along the thickness direction of the light emitting element 13 in a direction from the drive substrate 11 side toward the light emitting element 13.
As illustrated in
A method of manufacturing the display device 10C according to the third embodiment will be described. Here, a method of manufacturing the display device 10C illustrated in the drawing will be described. However, a case where the second refractive index portion 34 is a space portion is taken as an example.
After the anode electrode 130 separated for each sub-pixel 101 is formed on the first surface of the drive substrate 11, the side wall protective layer 16 is formed on the entire surface of the first surface by a PCVD method (Plasma CVD (plasma-enhanced chemical vapor deposition) method) (for example, a layer is formed with a thickness of 2000 nm), and the opening 160 is formed for each sub-pixel 101 by using a lithography method or the like (
Next, the organic layer 131 (for example, a layer having a thickness of about 1000 nm) is formed along the surface on the first surface side by using a vapor deposition method or the like, and the first cathode electrode 132 is further formed. The formation of the first cathode electrode 132 can be realized by forming an IZO film (for example, a film having a thickness of about 50 nm) on the first surface side using, for example, a reactive sputtering method or the like. At this time, the organic layer 131 and the first cathode electrode 132 are also formed on the side surface portion 160A formed in the opening 160 of the side wall protective layer 16.
Thereafter, the element protective layer 15 is formed on the first surface side (
As illustrated in
Further, as illustrated in
Next, the side wall protective layer 16 is further formed on the first surface side using a low-temperature PCVD method or the like. The thickness of a portion of the side wall protective layer 16 further additionally formed in this step is, for example, about 50 nm. Then, the end surface of the connection portion 35 exposed to the first surface side and the side wall protective layer 16 formed on the element protective layer 15 are removed by a dry etching method or the like. At this time, the side wall protective layer 16 is formed so as to cover the portion of the first cathode electrode 132 to be the connection portion 35 (
Then, as illustrated in
After the formation of the second cathode electrode 134, the display device 10C can be obtained in a similar manner to the method of manufacturing the display device described in the first embodiment.
In the above description of the manufacturing method, the second refractive index portion 34 is a space portion, but may be filled with another material instead of the space portion. For example, the side wall protective layer 16 (and the first refractive index portion 33) may be silicon nitride, and the second refractive index portion 34 may be a silicon oxide film.
In this regard, in the display device 10C according to the third embodiment, the first refractive index portion 33 and the second refractive index portion 34 having different refractive indexes are formed in the side wall protective layer 16 at the position of the side portion of the light emitting element 13 for each sub-pixel 101. Since the first refractive index portion 33 and the second refractive index portion 34 can be formed on the side portion of the light emitting element 13 so as to surround the light emitting element 13, total reflection can be generated. Furthermore, in the display device 10C according to the third embodiment, since the structure of the connection portion 35 connecting the second cathode electrode 134 and the first cathode electrode 132 can also be formed so as to surround the light emitting element 13, structural variations are less likely to occur in all directions.
As a display device using an organic EL element, in a display device having a structure in which an organic layer including at least an organic light emitting layer and a first cathode electrode are laminated on an anode electrode formed separately for each pixel, the first cathode electrode is separated for each sub-pixel. For this reason, a display device in which a second cathode electrode is connected on a first cathode electrode has been proposed. In such a display device, structural variation (asymmetry) may occur at a structurally connected portion and other portions. In the display device 10C as described above, the reliability of the light emission state can be improved by eliminating the structural variation and improving the light use efficiency.
Next, a modification example of the display device 10C according to the third embodiment will be described. In the display device 10C according to the third embodiment, the second cathode electrode 134 is provided on the element protective layer 15 in the lower protective layer 17, but as illustrated in
A method of manufacturing the display device 10C will be described particularly with an example in which the second refractive index portion 34 is a space portion. After the anode electrode 130 separated for each sub-pixel 101 is formed on the first surface of the drive substrate 11, the organic layer 131 is formed with a predetermined thickness (specifically, for example, the thickness is about 1000 nm.) using a vacuum deposition method or the like. Moreover, the first cathode electrode 132 is formed with a predetermined thickness (specifically, for example, the IZO film has a thickness of about 50 nm.) so as to cover the organic layer 131.
Next, the layer 37 is formed on the first surface with a material for forming the third refractive index portion 36. The material forming the third refractive index portion 36 can be, for example, a PSiO film (plasma silicon oxide film). As the thickness of this layer 37, for example, a thickness of about 2000 nm can be exemplified. Then, a resist 40 having a pattern corresponding to the organic layer 131 and the first cathode electrode 132 is formed on the first surface of the layer 37 (
Next, the resist 40 is removed, and the layer 38 of the material for forming the side wall protective layer 16 and the layer 39 of the material for forming the third refractive index portion 36 are sequentially laminated (
Moreover, the layer 38 of the material forming the side wall protective layer 16 and the layer 39 forming the third refractive index portion 36 are partially removed using a dry etching method or the like (
Next, as illustrated in
Moreover, a portion of the layer exposed to the first surface side among the layer 37 and the layer 39 of the material forming the third refractive index portion 36 is selectively removed by dry etching. At this time, a portion of the layer 37 formed on the surface of the first cathode electrode 132 and the layer 37 adjacent to the layer 38 with the layer 39 interposed therebetween is a space portion. Note that the layer 37 formed around the anode electrode 130 remains embedded in the layer 41. Furthermore, a space portion formed by the portion of the layer 39 becomes the second refractive index portion 34. Furthermore, a portion of the layer 37 sandwiched between the space portion formed by the portion of the layer 38 and the second refractive index portion 34 becomes the first refractive index portion 33 (
Then, the second cathode electrode 134 is formed with a predetermined thickness (for example, the thickness is 100 nm.) on the entire surface on the first surface side by a sputtering method or the like (
Note that it is possible to avoid formation of the second cathode electrode 134 in the space portion to be the second refractive index portion 34 depending on the conditions of the sputtering method using the material of the second cathode electrode 134.
After the formation of the second cathode electrode 134, the display device 10C according to the first modification example of the third embodiment can be obtained in a similar manner to the method of manufacturing the display device 10A described in the first embodiment.
Note that, in the first modification example, the third refractive index portion 36 is formed around the anode electrode 130, but the third refractive index portion 36 may be omitted.
Also in the first modification example, the similar effect to the effect described in the third embodiment can be obtained.
A display device 10D according to a fourth embodiment will be described. In the display device 10D according to the fourth embodiment, as illustrated in
In the display device 10D according to the fourth embodiment, the metal layer 46 is charged between the mutually adjacent connection portions 45 connected to the first cathode electrodes 132 of the adjacent light emitting elements 13. That is, metal is charged between the mutually adjacent connection portions 45 connected to the first cathode electrode 132 of each sub-pixel 101, and the metal layer 46 includes the charged metal.
In the display device 10D of the fourth embodiment illustrated in the example of
In the display device 10D according to the fourth embodiment, as described above, the metal layer 46 is charged between the adjacent connection portions 45 connected to the adjacent first cathode electrodes 132. In the example of
With respect to the dimension of the metal layer 46 in the vertical direction, it is preferable that the upper end (end portion on the first surface side) of the metal layer 46 is positioned at or near the upper end of the side wall 15A of the element protective layer 15, and the lower end (end portion on the second surface side) of the metal layer 46 is positioned at or near the formation position of the coupling portion 47 of the second cathode electrode 134.
As illustrated in
The material of the element protective layer 15 is not particularly limited, and the material described in the first embodiment can be used. For example, the material of the element protective layer 15 may be SiN or the like. Furthermore, the element protective layer 15 may be a single layer or may have a multilayer structure. For example, the element protective layer 15 may have a laminated structure of a layer including SiN and an AlOx film by atomic layer deposition (ALD).
In the fourth embodiment, similarly to the first embodiment, the upper protective layer 19 is formed so as to cover the second cathode electrode 134. In the example of
A method of manufacturing the display device 10D according to the fourth embodiment will be described. Here, a method of manufacturing the display device 10D illustrated in
First, the anode electrode 130 and the insulating layer 14 are formed on the drive substrate 11, and the organic layer 131, the first cathode electrode 132, and the element protective layer 15 are formed. Next, the second cathode electrode 134 is formed on the first surface. As a method of forming the second cathode electrode 134, it is preferable to use a method excellent in film forming coatability, such as ALD, for example. The second cathode electrode 134 covers the first cathode electrode 132 on the upper surface side of the element protective layer 15. Furthermore, the second cathode electrode 134 forms a connection portion 45 at a portion extending toward the drive substrate 11 side along the side wall 15A of the element protective layer 15. The connection portion 45 formed on the second cathode electrode 134 is connected to the side wall 132B of the first cathode electrode 132 at a predetermined position on the lower end side thereof. Then, the adjacent connection portions 45 connected to the adjacent first cathode electrodes 132 are connected, and a portion connecting the connection portions 45 forms the coupling portion 47.
Next, the metal layer 46 is formed on the entire surface so as to cover the second cathode electrode 134 (
Moreover, the upper protective layer 19 is formed on the first surface side, and the upper protective layer 19 and the counter substrate 21 are fixed via the filling resin layer 20. Thus, the display device 10D is obtained.
As a display device using an organic EL element, in a display device having a structure in which an organic layer including at least an organic light emitting layer and a first cathode electrode are laminated on an anode electrode formed separately for each pixel, the first cathode electrode is separated for each sub-pixel. For this reason, a display device in which a second cathode electrode is connected on a first cathode electrode has been proposed. In such a display device, the connection portion between the second cathode electrode and the first cathode electrode may be formed using a film forming technique or the like. In a case where a material such as ITO which is difficult to form a film is used as the material of the connection portion, a film having a sufficient thickness is hardly formed. For this reason, even in a case where a material that is difficult to form a film is used as the material of the connection portion, it is required to suppress disconnection failure of the connection portion and improve reliability of the light emitting state of the display device.
In the display device 10D according to the fourth embodiment, since the gap between the adjacent connection portions 45 is filled with the metal layer 46, conductivity can be maintained even if a disconnection failure occurs in the connection portion 45, and the reliability of the light emission state of the display device 10D can be improved. Furthermore, as also illustrated in
Next, a modification example of the display device 10D according to the fourth embodiment will be described.
In the description of the fourth embodiment, the light emission color of the organic layer 131 is the color type corresponding to the light emission color of the sub-pixel 101. However, in the display device 10D according to the fourth embodiment, similarly to the first modification example of the display device 10A according to the first embodiment, the light emission color of the light emitting element 13 may be a color type other than the color type corresponding to the light emission color of the sub-pixel 101 (First modification example). For example, in the display device 10D according to the first modification example of the fourth embodiment, as illustrated in the example of
In the display device 10D of the fourth embodiment, the layout of the sub-pixels 101R, 101G, and 101B is not limited. For example, the layout of the sub-pixels 101 may be a stripe-shaped pattern as illustrated in the example of
In the display device 10D of the fourth embodiment, similarly to the third modification example of the first embodiment, as illustrated in
In the display device 10D according to the third modification example of the fourth embodiment, the resonator structure 24 includes the second cathode electrode 134 and the light emitting element 13. The resonator structure 24 is similar to that described in the third modification example of the first embodiment. In the example of
According to the display device 10D, even if the element protective layer 15 has different thicknesses as described above, the metal layer 46 is charged between the adjacent connection portions 45, so that it is possible to suppress a defect in the conductive state due to a disconnection defect of the connection portion 45 of the second cathode electrode 134.
In the display device 10D of the third modification example of the fourth embodiment, as illustrated in
In the display device 10D according to the fourth modification example of the fourth embodiment, as illustrated in
A display device 10E according to a fifth embodiment will be described. In the example of the display device 10E according to the fifth embodiment illustrated in
In the example of the display device 10E illustrated in
The peripheral edge inner portion 50 is a portion formed inside the peripheral edge portion 130A of the anode electrode 130 in the laminated structure 52 of the organic layer 131 and the first cathode electrode 132, and is formed in a portion inside (center side) the opening end edge 140 of the opening 14A. In the example illustrated in
The outer edge portion 51 is a portion of the laminated structure 52 outside the peripheral edge inner portion 50. In the laminated structure 52, a predetermined portion including the raised portion 53 is the outer edge portion 51. Since the outer edge portion 51 is avoided from being connected to the second cathode electrode 134, it is possible to avoid the organic layer 131 formed on the raised portion 53 from contributing to light emission in the sub-pixel 101.
In the display device 10E according to the fifth embodiment, the lower protective layer 17 is formed so as to cover the first cathode electrode 132. In the lower protective layer 17 illustrated in the example of
In the display device 10E according to the fifth embodiment illustrated in the example of
A method of manufacturing the display device 10E according to the fifth embodiment will be described. Here, a method of manufacturing the display device 10E illustrated in
The anode electrode 130 and the insulating layer 14 are formed on the drive substrate 11, and the organic layer 131B, the first cathode electrode 132, and the lower protective layer 17 are formed (
After the peripheral edge inner portion formation step, a lower protective layer 17 is further formed on the first surface side (
The second cathode electrode 134 is formed on one surface (over the entire surface) on the first surface of the lower protective layer 17. As a method of forming the second cathode electrode 134, for example, sputtering or the like is preferably used. The contact hole 55 has a shape and a diameter such that a film of a material (for example, IZO or the like) for forming the second cathode electrode 134 can be formed, and the second cathode electrode 134 is extended from the first surface side of the lower protective layer 17 to the first surface of the first cathode electrode 132 along the inner peripheral surface of the contact hole 55. At this time, the extension portion 56 as the connection portion 57 is formed. Furthermore, the first cathode electrode 132 and the second cathode electrode 134 are connected by the connection portion 57 (
Then, similarly to the first embodiment and the like, the upper protective layer 19 is formed on the second cathode electrode 134, and the counter substrate 21 is disposed with the filling resin layer 20 interposed therebetween, thereby obtaining the display device 10E (not illustrated).
In a display device using an organic EL element, an insulating layer may cover an end portion of an anode electrode, and the anode electrode may be exposed from an opening formed in the insulating layer. In this case, the laminated structure of the first cathode electrode and the organic layer rises at the position of the opening end edge of the opening. When such a bulge occurs in the sub-pixel, light emission different from the central portion of the sub-pixel may occur at the peripheral edge of the sub-pixel (edge light emission), or light emission of adjacent sub-pixels may occur (adjacent pixel light emission). Therefore, it is required to improve the reliability of the light emission state of the display device.
In the display device 10E according to the fifth embodiment, the laminated structure 52 of the organic layer 131 and the first cathode electrode 132 is separated into the peripheral edge inner portion 50 and the outer edge portion 51, and the second cathode electrode 134 is connected to the first cathode electrode 132 in the peripheral edge inner portion 50. The raised portion 53 of the laminated structure 52 of the first cathode electrode 132 and the organic layer 131 is hardly included in the peripheral edge inner portion 50, and edge light emission and adjacent pixel light emission can be suppressed. Therefore, according to the display device 10E according to the fifth embodiment, the reliability of the light emission state can be improved. In addition, since edge light emission and adjacent pixel light emission can be suppressed, it is easy to increase the luminance and definition of the display device 10E.
Next, a modification example of the display device 10E according to the fifth embodiment will be described.
In the display device 10E according to the fifth embodiment, as illustrated in
In the example illustrated in
Furthermore, in the display device 10E according to the first modification example of the fifth embodiment, a sidewall portion 60 rising in a direction away from the drive substrate 11 (+Z direction) is formed on the first surface side. The sidewall portion 60 may be a single layer or a plurality of layers may be laminated. In the example of
Next, a method of manufacturing a display device 10E according to the first modification example of the fifth embodiment will be described.
First, the anode electrode 130 is formed on the drive substrate 11, the organic layer 131B and the first cathode electrode 132 are formed, and a layer 62 of a material for forming the lower protective layer 17 is further formed (
Similarly to the case of the sub-pixel 101B, the sidewall portion 60 is formed for the sub-pixel 101G. At this time, the sidewall portion 60 is laminated on the sub-pixel 101B. Moreover, the sidewall portion 60 is also formed in the sub-pixel 101R. At this time, the sidewall portions 60 are laminated on the sub-pixels 101G and 101B (
Moreover, a layer 63 of a material for forming the lower protective layer 17 is formed on the entire surface on the first surface side (
As described in the above manufacturing method of the display device 10E according to the fifth embodiment, the contact hole 55 is formed at the predetermined position determined for each sub-pixel 101 with respect to the lower protective layer 17, and the second cathode electrode 134 is formed, whereby the first cathode electrode 132 and the second cathode electrode 134 are connected at the extension portion 56 forming the connection portion 57. Then, as described in the above-described manufacturing method of the display device 10E according to the fifth embodiment, the upper protective layer 19, the filling resin layer 20, and the counter substrate 21 are provided, and the display device 10E according to the first modification example of the fifth embodiment can be obtained.
Also in the display device 10E according to the first modification example of the fifth embodiment, it is possible to obtain the similar effects to those described in the operational effects of the display device 10E according to the fifth embodiment.
In the display device 10E according to the fifth embodiment, the anode electrode 130 is formed in a planar shape, but the shape of the anode electrode 130 is not limited thereto, and may be formed in a curved shape as illustrated in
A curved portion 65 curved in a concave shape is formed in a predetermined region inside the anode electrode 130. The laminated structure 52 of the organic layer 131 and the first cathode electrode 132 is formed on the first surface of the anode electrode 130 and in the formation region of the curved portion 65, and in the example of
A display device 10E according to the second modification example of the fifth embodiment can be manufactured, for example, as follows.
A recessed portion 111 is formed at a predetermined position on the drive substrate 11, the anode electrode 130 and the insulating layer 14 are formed, and the organic layer 131, the first cathode electrode 132, and the lower protective layer 17 are formed (
Next, the lower protective layer 17, the first cathode electrode 132, and the organic layer 131 are patterned in accordance with the pattern of the sub-pixel 101 (
Next, the lower protective layer 17 is additionally formed on the entire surface on the first surface side (
Moreover, as described in the above-described manufacturing method of the display device 10E according to the fifth embodiment, the contact hole 55 is formed at a predetermined position determined for each sub-pixel 101 with respect to the lower protective layer 17, and the second cathode electrode 134 is formed, whereby the first cathode electrode 132 and the second cathode electrode 134 are connected at the extension portion 56 forming the connection portion 57 (
In a case where the display device has a curved anode electrode, since the curved inclined surface is formed from the curvature start position toward the curved bottom portion in the curved portion, the thickness of the organic layer tends to be thinner than that in the vicinity of the curved bottom portion, and uniformity of the light emission state is more required at the curved bottom portion and the curvature start position. Furthermore, it is required to suppress the influence of the step on the light emitting state at the opening edge portion formed at the peripheral edge portion of the anode electrode.
According to the display device 10E according to the second modification example of the fifth embodiment, since the laminated structure 52 of the organic layer 131 and the first cathode electrode 132 is formed in the region of the curved portion 65, it is possible to eliminate the request itself of the necessity of achieving uniformity of the light emission state between the bottom portion of the curved portion 65 and the end edge position of the curved portion 65. Furthermore, the laminated structure 52 can be formed at a position avoiding the step at the opening end edge 140. Therefore, in the display device 10E according to the second modification example of the fifth embodiment, the reliability of the light emission state of the display device 10E can be improved.
In the second modification example of the fifth embodiment, the laminated structure 52 of the first cathode electrode 132 and the organic layer 131 is removed in the portion outside the curved portion 65, but as illustrated in
In the display device 10E according to the third modification example of the fifth embodiment, since the portion 66 of the laminated structure 52 can be prevented from contributing to light emission, it is possible to obtain an effect similar to that of the display device 10E according to the second modification example of the fifth embodiment.
In the fifth embodiment and the second to third modification examples thereof, the shape of the curved portion 65 is a hemispherical curved shape, but the shape of the curved portion 65 is not limited thereto. As illustrated in
As illustrated in
In the display device 10E according to the fifth embodiment, as described in the manufacturing method, the groove 58 for separating and forming the peripheral edge inner portion 50 and the outer edge portion 51 is formed using lithography, etching, or the like. Therefore, it is required to suppress the shift of the formation position of the groove 58 at the time of performing the lithography method. Furthermore, in a case where the position to be etched is determined in consideration of the deviation of the formation position of the groove 58 in advance, the laminated structure 52 of the organic layer 131 and the first cathode electrode 132 is required to be designed so that the groove 58 is not formed at an inner position more than necessary on the first surface of the anode electrode 130. In a state in which the region of the peripheral edge inner portion 50 becomes smaller than necessary at a position shifted from the opening end edge 140 of the opening 14A, for example, a state as illustrated in
A method of manufacturing a display device according to a sixth embodiment will be described. The peripheral edge inner portion forming step is performed as follows. Similarly to the fifth embodiment, the anode electrode 130 and the insulating layer 14 are formed on the drive substrate 11, and the organic layer 131, the first cathode electrode 132, and the lower protective layer 17 are formed. At this time, as described in the fifth embodiment, the laminated structure 52 of the first cathode electrode 132 and the organic layer 131 is raised to form the raised portion 53 so as to cover the step T by the opening end edge 140 at the position of the peripheral edge portion 130A of the anode electrode 130. At this time, a raised portion 54 is also formed on the upper surface of the lower protective layer 17 formed on the laminated structure 52 at a position corresponding to the raised portion 53. Then, a resist 70 is entirely applied to the first surface side of the lower protective layer 17 (
The thickness of the lower protective layer 17 laminated on the first cathode electrode 132 is such that the raised portion 54 can also be formed on the lower protective layer 17 at the position of the opening end edge 140 of the opening 14A. Furthermore, although depending on the materials of the lower protective layer 17 and the resist 70, in consideration of a processing selection ratio at the time of etching of the lower protective layer 17 to be described later, the thickness of the lower protective layer 17 is preferably about 3 times the height of a step (a step formed by the insulating layer 14 riding on the anode electrode 130) at the position of the opening end edge 140 of the opening 14A. For example, in a case where the height of the step at the position of the opening end edge 140 of the opening 14A is 100 nm, the thickness of the lower protective layer 17 is preferably about 300 nm.
Next, dry etching is performed to gradually delete the resist 70. Dry etching is performed until the raised end of the raised portion 54 in the lower protective layer 17 starts to be exposed (
Using the remaining part of the resist 70 left without being etched as a mask, the lower protective layer 17, the first cathode electrode 132, and the organic layer 131 are removed by dry etching (
Then, the resist 70 left on the lower protective layer 17 and used as a mask is removed by ashing or the like (
In the display device according to the sixth embodiment, the peripheral edge inner portion 50 is suppressed from becoming smaller than necessary while being maintained in a range inside the opening end edge 140. Therefore, in the display device, the light emitting region of the pixel is not excessively small, and the area of the light emitting region can be secured, so that high luminance can be easily realized.
Furthermore, according to the method of manufacturing the display device according to the sixth embodiment described above, since the etching position of the lower protective layer 17 for determining the outer edge position of the peripheral edge inner portion 50 is determined slightly inside the raised end or the raised end of the raised portion 54 by etching of the resist 70, the peripheral edge inner portion 50 is formed in the approximate center of the anode electrode 130 in a self-aligned manner as illustrated in
Moreover, according to the method of manufacturing a display device according to the sixth embodiment described above, the total thickness of the organic layer 131, the first cathode electrode 132, and the lower protective layer 17 can be made uniform at the position of the outer peripheral edge of the peripheral edge inner portion 50.
In the display device according to the sixth embodiment, as illustrated in
According to the display device according to the modification example of the sixth embodiment, as illustrated in
Then, since the raised portion 54 is particularly erected, it is easy to recognize the raised end of the raised portion 54 in the lower protective layer 17 at the time of dry etching of the resist.
The display device 10A according to the first embodiment and the modification examples thereof may combine the second embodiment to the sixth embodiment (Seventh embodiment). The seventh embodiment is a combination of the first embodiment and the second to sixth embodiments, but this does not limit the combination of the embodiments in the present specification.
In a case where the display device 10B according to the second embodiment is combined with the display device 10A according to the first embodiment, in the display device 10A according to the first embodiment, the connection portion 18 is provided so as to surround the light emitting region P of the light emitting element 13, the side wall protective layer 16 is provided between the adjacent light emitting elements 13, and the inner portion of the connection portion 18 is configured so as to have a refractive index different from the refractive index of the side wall protective layer 16. Furthermore, the first to third modification examples of the display device 10B according to the second embodiment may be combined with the display device 10A according to the first embodiment. That is, for example, the connection portion 18 may be configured by the via 31 similarly to the connection portion 30.
The display device 10C according to the third embodiment and the first modification example thereof may be combined with the display device 10A according to the first embodiment. That is, in the display device 10A according to the first embodiment, in the side wall protective layer 16, the first refractive index portion 33 may be formed from the side closer to the light emitting element 13 at the position of the side region M of the light emitting element 13, and the second refractive index portion 34 having a lower refractive index may be formed outside the first refractive index portion 33. Also in the display device 10A according to the first embodiment in which the display device 10C according to the third embodiment is combined, similarly to the third embodiment, the first refractive index portion 33 and the second refractive index portion 34 are formed on the side portion of the light emitting element 13, so that light use efficiency can be improved.
Furthermore, the display device 10D according to the fourth embodiment may be combined with the display device 10A according to the first embodiment. Also in this case, as long as the metal layer 46 is formed between the adjacent connection portions 18, the metal layer 46 may be buried in the side wall protective layer 16.
Also in the display device 10A according to the first embodiment in which the display device 10D according to the fourth embodiment is combined, similarly to the fourth embodiment, it is possible to suppress the defect of the conductive state due to the disconnection defect of the connection portion.
The display device 10E according to the fifth embodiment may be combined with the display device 10A according to the first embodiment. As an example of this case, it is only required that the element protective layer 15 be formed on the first surface of the peripheral edge inner portion 50 formed inside the anode electrode, and the connection portion 18 be formed along the side wall 15A of the element protective layer 15.
The display device 10A according to the first embodiment in which the fifth embodiment is combined can also obtain the similar effects to those of the fifth embodiment.
When the method of manufacturing the display device 10A according to the first embodiment in combination with the fifth embodiment is performed, the method of manufacturing the display device according to the sixth embodiment may be performed.
A display device 10 according to one of the above-described embodiments may be provided in various electronic apparatuses. Especially, this is preferably provided in an electronic viewfinder of a video camera or a single-lens reflex camera, a head mounted display, or the like in which high resolution is required, used for enlarging near the eyes. Note that, in the description of the present application example, the display devices (the display device 10A and the like) according to the first to seventh embodiments are collectively referred to as a display device 10.
A monitor 314 is provided at a position shifted to the left from the center of a rear surface of the camera main body 311. An electronic viewfinder (eyepiece window) 315 is provided above the monitor 314. By looking through the electronic viewfinder 315, the photographer can visually confirm a light image of a subject guided from the imaging lens unit 312 and determine a picture composition. As the electronic viewfinder 315, any display device 10 according to one of the above-described embodiments and modification examples thereof may be used.
Although the display device, the manufacturing method, and the application example according to the first to seventh embodiments and the modification examples of the present disclosure have been specifically described above, the present disclosure is not limited to the display device and the application example according to the first to seventh embodiments and the modification examples described above, and various modifications based on the technical idea of the present disclosure are possible.
For example, the configurations, methods, steps, shapes, materials, numerical values, and the like described in the display device, the manufacturing method, and the application example according to the first to seventh embodiments and the modification examples described above are merely examples, and configurations, methods, steps, shapes, materials, numerical values, and the like different from those described above may be used as necessary.
The configurations, methods, steps, shapes, materials, numerical values, and the like of the display device, the manufacturing method, and the application example according to the first embodiment to the seventh embodiment and the modification examples described above can be combined with each other without departing from the gist of the present disclosure.
The materials exemplified in the display device, the manufacturing method, and the application example according to the first to seventh embodiments and the modification examples described above can be used alone or in combination of two or more unless otherwise specified.
Furthermore, the present disclosure can also adopt the following configurations.
(1) A display device including:
(2) The display device according to (1) described above, in which
(3) The display device according to (1) or (2) described above, in which
(4) The display device according to any one of (1) to (3) described above, in which
(5) The display device according to any one of (1) to (4) described above, in which
(6) The display device according to any one of (1) to (4) described above, in which
(7) The display device according to any one of (1) to (6) described above, further including
(8) The display device according to any one of (1) to (7) described above, in which
(9) The display device according to (8) described above, in which
(10) The display device according to any one of (1) to (9) described above, in which
(11) The display device according to (10) described above, in which
(12) The display device according to (10) or (11) described above, in which
(13) The display device according to (12) described above, in which
(14) The display device according to (13) described above described above, further including
(15) The display device according to any one of (1) to (14) described above, further including
(16) The display device according to (15) described above, in which
(17) The display device according to any one of (1) to (16) described above, in which
(18) The display device according to any one of (1) to (17) described above, further including
(19) The display device according to any one of (1) to (17) described above, in which
(20)
An electronic apparatus including
Furthermore, according to the second embodiment of the present disclosure, the following configuration can also be adopted.
(21) A display device including:
(22) The display device according to (21) described above, in which
(23) The display device according to (21) described above, in which
(24) The display device according to any one of (21) to (23) described above, in which
(25) The display device according to (24) described above, further including
(26) The display device according to (25) described above, in which
(27) The display device according to any one of (24) to (26) described above, in which
(28) The display device according to (27) described above, in which
(29) The display device according to any one of (21) to (28) described above, further including
Furthermore, according to the third embodiment of the present disclosure, the following configuration can also be adopted.
(30) A display device including:
(31) The display device according to (30) described above, in which
(32) The display device according to (30) or (31) described above, in which
(33) The display device according to any one of (30) to (32) described above, in which
According to the fourth embodiment of the present disclosure, the following configuration can also be adopted.
(34) A display device including:
(35) The display device according to (34) described above, in which a metal halogen compound that forms the metal layer has a boiling point of 100° ° C. or lower under vacuum conditions.
According to the fifth embodiment and the sixth embodiment of the present disclosure, the following configuration can also be adopted.
(36) A display device including:
(37) A plurality of light emitting elements including an anode electrode, an organic layer, and a first cathode electrode, the anode electrode, the organic layer, and the first cathode electrode being separated for each sub-pixel;
(38) The display device according to (36) described above, in which
(39) The display device according to (36) to (38) described above, in which
(40) The display device according to (36) or (37) described above, in which
(41) A method of manufacturing a display device, the method including the steps of:
According to the second to sixth embodiments of the present disclosure, the following configuration can also be adopted.
(42) An electronic apparatus including the display device according to any one of (21) to (41) described above.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2021-080633 | May 2021 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2022/016810 | 3/31/2022 | WO |
