Light-emitting device, method for manufacturing light-emitting device, and image display device

Abstract

Provided is a light-emitting device in which the aperture ratio of a light-emitting element is improved. A light-emitting device according to an embodiment of the present disclosure comprises a substrate, a light-emitting element, an electrode layer, a contact electrode layer, a first insulating film, and a transparent electrode. The light-emitting element is provided on the substrate and includes an opposing surface, a light emission surface, and an end surface. The electrode layer is in contact with all the regions of the light emission surface. The contact electrode layer is provided in a second region of the substrate, the second region being different from a first region in which the light-emitting element is provided, and includes a surface opposite the substrate. The first insulating film covers the end surface of the light-emitting element. The transparent electrode continuously covers all the regions of the electrode layer and the first insulating film and is electrically connected to the surface of the contact electrode layer. Here, the portion in the transparent electrode, which covers all the regions of the electrode layer, is only a flat portion extending along the light emission surface.

Description

Light-emitting device, manufacturing method for light-emitting device, and image display device

[0001] The present disclosure relates to a light-emitting device, a method for manufacturing the light-emitting device, and an image display device including the light-emitting device.

[0002] To date, for example, an image display element has been proposed that includes a common P electrode that is horizontal to the light emission surfaces of a plurality of micro light-emitting elements and is provided in contact with the light emission surfaces (see, for example, Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2021-019015

[0004] Incidentally, in a light-emitting device using a micro-LED (Light Emitting Diode), the aperture ratio of the light-emitting surface of the light-emitting element may be limited by the step structure of a transparent electrode provided on the upper part of the light-emitting surface of the light-emitting element.

[0005] A light-emitting device according to an embodiment of the present disclosure includes a substrate, a light-emitting element, an electrode layer, a contact electrode layer, a first insulating film, and a transparent electrode. The light-emitting element is provided on the substrate and includes a facing surface facing the substrate, a light-emitting surface opposite the facing surface, and an end surface connecting the facing surface and the light-emitting surface. The electrode layer is in contact with the entire area of ​​the light-emitting surface. The contact electrode layer is provided in a second region of the substrate different from the first region in which the light-emitting element is provided, and includes a surface located opposite the substrate. The first insulating film covers the end surface of the light-emitting element. The transparent electrode continuously covers the entire area of ​​the electrode layer and the first insulating film and is electrically connected to the surface of the contact electrode layer. Here, the portion of the transparent electrode that covers the entire area of ​​the electrode layer is only a flat portion that extends along the light-emitting surface. An image display device according to an embodiment of the present disclosure includes the light-emitting device described above.

[0006] A manufacturing method of a light-emitting device according to one embodiment of the present disclosure includes forming, on a substrate, a contact electrode layer and a light-emitting element having a light-emitting surface on the opposite side of the substrate; covering the contact electrode layer and the light-emitting element with an insulating film; selectively etching the insulating film to expose the entire area of ​​the light-emitting surface and at least a portion of the contact electrode layer; and forming a transparent electrode that continuously covers the entire area of ​​the light-emitting surface of the light-emitting element and the insulating film and is electrically connected to the contact electrode layer.

[0007] In the light emitting device according to an embodiment of the present disclosure, emitted light can be obtained from the entire area of ​​the light emitting surface of the light emitting element.

[0008] FIG. 1 is a cross-sectional view schematically illustrating an example of the configuration of a light-emitting device according to a first embodiment of the present disclosure. FIG. 2 is a plan view schematically illustrating an example of the configuration of the light-emitting device shown in FIG. 1. FIG. 3A is a cross-sectional view schematically illustrating an example of a manufacturing process for the light-emitting device shown in FIG. 1. FIG. 3B is a cross-sectional view schematically illustrating a process subsequent to FIG. 3A. FIG. 3C is a cross-sectional view schematically illustrating a process subsequent to FIG. 3B. FIG. 3D is a cross-sectional view schematically illustrating a process subsequent to FIG. 3C. FIG. 3E is a cross-sectional view schematically illustrating a process subsequent to FIG. 3D. FIG. 3F is a cross-sectional view schematically illustrating a process subsequent to FIG. 3E. FIG. 3G is a cross-sectional view schematically illustrating a process subsequent to FIG. 3F. FIG. 3H is a cross-sectional view schematically illustrating a process subsequent to FIG. 3G. FIG. 3I is a cross-sectional view schematically illustrating a process subsequent to FIG. 3H. FIG. 4 is a cross-sectional view schematically illustrating an example of the configuration of a light-emitting device according to a second embodiment of the present disclosure. FIG. 5 is a plan view schematically illustrating an example of the configuration of the light-emitting device shown in FIG. 4. FIG. 6A is a cross-sectional view schematically illustrating an example of a manufacturing process for the light-emitting device shown in FIG. 4. 6B is a schematic cross-sectional view showing a step subsequent to FIG. 6A . FIG. 6C is a schematic cross-sectional view showing a step subsequent to FIG. 6B . FIG. 7 is a schematic cross-sectional view showing an example of the configuration of a light-emitting device according to Modification 1 of the present disclosure. FIG. 8 is a schematic cross-sectional view showing an example of the configuration of a light-emitting device according to Modification 2 of the present disclosure. FIG. 9 is a schematic plan view showing an example of the configuration of a light-emitting device according to Modification 3 of the present disclosure. FIG. 10A is a schematic plan view showing an example of the configuration of a light-emitting device according to Modification 4 of the present disclosure. FIG. 10B is a schematic plan view showing another example of the configuration of a light-emitting device according to Modification 4 of the present disclosure. FIG. 10C is a schematic plan view showing another example of the configuration of a light-emitting device according to Modification 4 of the present disclosure. FIG. 11 is a schematic cross-sectional view showing an example of the configuration of a light-emitting device according to Modification 5 of the present disclosure. FIG. 12 is a schematic cross-sectional view showing an example of the configuration of a light-emitting device according to the third embodiment of the present disclosure. FIG. 13 is a schematic plan view showing an example of the configuration of the light-emitting device shown in FIG. 12 . FIG. 14 is an enlarged cross-sectional view of a portion of the configuration of the light-emitting device shown in FIG. 12 . Fig. 15A is a cross-sectional view illustrating an example of a manufacturing process for the light-emitting device shown in Fig. 12. Fig. 15B is a cross-sectional view illustrating a process following Fig. 15A. Fig. 15C is a cross-sectional view illustrating a process following Fig. 15B. Fig. 15D is a cross-sectional view illustrating a process following Fig. 15C. Fig. 15E is a cross-sectional view illustrating a process following Fig. 15D.15F is a schematic cross-sectional view illustrating a step subsequent to FIG. 15E. FIG. 15G is a schematic cross-sectional view illustrating a step subsequent to FIG. 15F. FIG. 15H is a schematic cross-sectional view illustrating a step subsequent to FIG. 15G. FIG. 15I is a schematic cross-sectional view illustrating a step subsequent to FIG. 15H. FIG. 16 is a schematic cross-sectional view illustrating an example of a configuration of a light-emitting device according to Modification 6 of the present disclosure. FIG. 17 is a schematic cross-sectional view illustrating an example of a configuration of a light-emitting device according to Modification 7 of the present disclosure. FIG. 18 is a schematic plan view illustrating an example of a configuration of a light-emitting device according to Modification 8 of the present disclosure. FIG. 19 is a schematic cross-sectional view illustrating an example of a configuration of a light-emitting device according to Modification 9 of the present disclosure. FIG. 20 is a schematic cross-sectional view illustrating an example of a configuration of a light-emitting device according to Modification 10 of the present disclosure. FIG. 21 is a perspective view illustrating an example of a configuration of an image display device according to an application example of the present disclosure. FIG. 22 is a schematic view illustrating an example of a wiring layout of the image display device shown in FIG. 21. FIG. 23 is a perspective view illustrating an example of a configuration of an image display device according to an application example of the present disclosure. Fig. 24 is a perspective view showing the configuration of the mounting substrate shown in Fig. 23. Fig. 25 is a perspective view showing the configuration of the unit substrate shown in Fig. 25. Fig. 26 is a diagram showing an example of an image display device according to an application example of the present disclosure. Fig. 27 is a cross-sectional schematic view showing an example of the configuration of a light-emitting device as a reference example.

[0009]

[0033] Hereinafter, an embodiment of the present disclosure will be described in detail with reference to the drawings. The following description is a specific example of the present disclosure, and the present disclosure is not limited to the following embodiment. Furthermore, the present disclosure is not limited to the arrangement, dimensions, dimensional ratios, etc. of the components shown in the drawings. The order of description is as follows: 1. First embodiment (example of a light-emitting device including a transparent electrode that covers the entire light-emitting surface of a light-emitting element) 1-1. Configuration 1-2. Manufacturing method 1-3. Actions and effects 2. Second embodiment (example of a light-emitting device including a transparent electrode that covers the entire light-emitting surface and rounded end faces of a light-emitting element and has side surfaces that are flush with the surface) 2-1. Configuration 2-2. Manufacturing method 2-3. Actions and effects 3. Modifications 3-1. Modification 1 (another example of a light-emitting device) 3-2. Modification 2 (another example of a light-emitting device) 3-3. Modification 3 (another example of a light-emitting device) 3-4. Modification 4 (another example of a light-emitting device) 3-5. Modification 5 (another example of a light-emitting device) 4. Third embodiment (an example of a light-emitting device having a heat dissipation section connected to a light-emitting element via a heat conduction path) 4-1. Configuration 4-2. Manufacturing method 4-3. Actions and effects 4-4. Modification 5. Application examples

[0010] 1. First Embodiment Fig. 1 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device 1 according to a first embodiment of the present disclosure. Fig. 2 is a schematic diagram illustrating an example of a planar configuration of the light-emitting device 1 illustrated in Fig. 1. The light-emitting device 1 is suitably applicable to a display panel of an image display device known as an LED display (for example, an image display device 100 illustrated in Fig. 21 described below).

[0011] [1-1. Configuration] The light-emitting device 1 includes, in the Z-axis direction, which is the thickness direction perpendicular to the XY plane, a drive substrate 30, one or more light-emitting elements 11, one or more first electrode layers 12, one or more second electrode layers 13, one or more transparent electrodes 14, multiple protective films 15, and multiple first insulating films 161. The light-emitting device 1 further includes one or more plugs 21, multiple contact electrode layers 22, one or more plugs 23, and one or more embedded layers 24. The drive substrate 30 corresponds to a specific example of a "substrate" as one aspect of the present disclosure. The second electrode layer 13 corresponds to a specific example of an "electrode layer" as one aspect of the present disclosure. Note that, in FIGS. 1 and 2 and FIGS. 3A to 3I described below, contact electrode layers 22-1 and 22-2 are illustrated as an example of multiple contact electrode layers 22.

[0012] The light-emitting element 11 is provided in each of a plurality of pixels constituting, for example, an image display device. That is, for example, one light-emitting element 11 is provided for one pixel. However, a plurality of light-emitting elements 11 may be provided for one pixel. The light-emitting element 11 is a solid-state light-emitting element that emits light in a predetermined wavelength band from the top surface, for example, an LED (Light Emitting Diode) chip. The LED chip refers to an element cut from a wafer used for crystal growth, and is not a packaged type covered with molded resin or the like. The LED chip is, for example, 100 μm or less in size and is a so-called micro LED.

[0013] The light-emitting element 11 has a facing surface 11S1 facing the drive substrate 30, a light-emitting surface 11S2 opposite the facing surface, and an end surface 11S3 connecting the facing surface and the light-emitting surface. The light-emitting surface 11S2 of the light-emitting element 11 is flat. The end surface 11S3 of the light-emitting element 11 is inclined at an angle of less than 90° with respect to the surface of the drive substrate 30. The light-emitting element 11 includes, for example, a first-conductivity-type layer 111, an active layer 112, and a second-conductivity-type layer 113, in this order from the drive substrate 30 side.

[0014] The first conductivity type layer 111 is formed, for example, from an n-type GaN-based semiconductor material. The active layer 112 has a multiple quantum well structure in which, for example, InGaN and GaN are alternately stacked, and has a light-emitting region within the layer. Light in the blue band of, for example, 430 nm to 500 nm is extracted from the active layer 112. Light with a wavelength corresponding to, for example, the ultraviolet region (ultraviolet light) may also be extracted from the active layer 112. The second conductivity type layer 113 is formed, for example, from a p-type GaN-based semiconductor material. In the light-emitting element 11, the upper surface of the second conductivity type layer 113, i.e., the surface opposite to the active layer 112, serves as a light-emitting surface 11S2 of the light-emitting element 11.

[0015] The first electrode layer 12 is provided between the drive substrate 30 and the light-emitting element 11 at a position overlapping the light-emitting element 11 in the Z-axis direction. The first electrode layer 12 includes, for example, a reflective film 121 and a contact layer 122 in this order in the Z-axis direction from the drive substrate 30 side.

[0016] The reflective film 121 has an opening 121H. The plug 23 penetrates the opening 121H in the reflective film 121. The reflective film 121 is formed using a light-reflective metal, a dielectric material, or a multilayer film formed by laminating these. Examples of metals used in the reflective film 121 include titanium (Ti), aluminum (Al), and silver (Ag).

[0017] The contact layer 122 is electrically connected to the drive substrate 30 via the plug 23. The contact layer 122 is in ohmic contact with, for example, the first conductivity type layer 111. The contact layer 122 is formed using a transparent conductive material such as a multilayer film (Ni / Au) of nickel (Ni) and gold (Au) or ITO. The contact layer 122 may be made of a metal such as Ti, TiN, TaN, Al, or Ag, or a multilayer film made by stacking these metals.

[0018] The second electrode layer 13 is provided so as to cover the entire area of ​​the light emitting surface 11S2 of the light emitting element 11. That is, the entire area of ​​the light emitting surface 11S2 is in contact with the second electrode layer 13. The second electrode layer 13 is also covered with a transparent electrode 14. That is, the entire area of ​​the upper surface 13S of the second electrode layer 13 opposite the light emitting surface 11S2 is in contact with the transparent electrode 14. The second electrode layer 13 is provided so as to cover the second conductivity type layer 113 of the light emitting element 11 and is in ohmic contact with the second conductivity type layer 113. The second electrode layer 13 is formed of a transparent electrode material such as ITO, indium zinc oxide (IZO), tin oxide (SnO), or TiO.

[0019] The transparent electrode 14 is provided so as to continuously cover the entire region of the second electrode layer 13 and the first insulating film 161. As described above, the transparent electrode 14 contacts the entire region of the upper surface 13S of the second electrode layer 13. Therefore, the light-emitting element 11 emits light from the entire region of the light-emitting surface 11S2. Furthermore, the only portion of the transparent electrode 14 that covers the entire region of the second electrode layer 13 is the flat portion 141 that extends along the light-emitting surface 11S2. In other words, the transparent electrode 14 is provided so that only the flat portion 141 of the transparent electrode 14 covers the entire region of the light-emitting surface 11S2. The entire region of the light-emitting surface 11S2 is uniformly covered by the flat portion 141 so as to contact the flat portion 141 of the transparent electrode 14. The transparent electrode 14 is electrically connected to the surface 22S1 of the contact electrode layer 22. The transparent electrode 14 electrically connects the light-emitting element 11 and the drive substrate 30. The transparent electrode 14 is formed of a transparent electrode material such as ITO, indium zinc oxide (IZO), tin oxide (SnO), or TiO.

[0020] The protective film 15 is provided between the end face 11S3 of the light emitting element 11 and the first insulating film 161. Furthermore, the protective film 15 extends along the surface of the embedded layer 24 on the side opposite to the drive substrate 30. The protective film 15 protects the light emitting surface 11S2 and end face 11S3 of the light emitting element 11 and the surface 24US of the embedded layer 24 during, for example, the manufacturing process of the light emitting device 1. The protective film 15 is made of, for example, aluminum oxide (Al ２ O ３), titanium nitride (TiN), resin, etc.

[0021] The first insulating film 161 is provided so as to cover the end face 11S3 of the light-emitting element 11. The first insulating film 161 is provided so as to fill the gap between the protective film 15 and the transparent electrode 14. The first insulating film 161 can be formed using, for example, silicon oxide (SiO), silicon nitride (SiN), plasma tetraethoxysilane (P-TEOS), or the like.

[0022] The plug 21 is provided in contact with the contact electrode layer 22, and electrically connects the contact electrode layer 22 to the drive substrate 30. The plug 21 is formed using, for example, copper (Cu), aluminum (Al), tungsten (W), silver (Ag), or an alloy thereof.

[0023] 2, at least a portion of the contact electrode layer 22 is provided in a region of the drive substrate 30 that is different from the region in which the light-emitting elements 11 are provided. The contact electrode layer 22 includes a surface 22S1 located on the opposite side to the drive substrate 30. The contact electrode layer 22 includes, for example, a reflective film 221 and a contact layer 222 in this order in the Z-axis direction from the drive substrate 30 side.

[0024] The reflective film 221 has an opening 221H. The plug 21 penetrates the opening 221H in the reflective film 221. The reflective film 221 is formed using a light-reflective metal, a dielectric material, or a multilayer film in which these are stacked. Examples of metals used in the reflective film 221 include titanium (Ti), aluminum (Al), and silver (Ag).

[0025] The contact layer 222 is electrically connected to the drive substrate 30 via the plug 21. The contact layer 222 is in ohmic contact with, for example, the first conductivity type layer 111. The contact layer 222 is formed using a transparent conductive material such as a multilayer film (Ni / Au) of nickel (Ni) and gold (Au) or ITO. The contact layer 222 may be made of a metal such as titanium (Ti), titanium nitride (TiN), tantalum nitride (TaN), aluminum (Al), or silver (Ag), or a multilayer film made by stacking these metals.

[0026] The reflective film 121 has an opening 121H. The plug 23 penetrates the opening 121H in the reflective film 121. The reflective film 121 is formed using a light-reflective metal, a dielectric material, or a multilayer film formed by laminating these. Examples of metals used in the reflective film 121 include titanium (Ti), aluminum (Al), and silver (Ag).

[0027] The contact layer 122 is electrically connected to the drive substrate 30 via the plug 23. The contact layer 122 is in ohmic contact with, for example, the first conductivity type layer 111. The contact layer 122 is formed using a transparent conductive material such as a multilayer film (Ni / Au) of nickel (Ni) and gold (Au) or ITO. The contact layer 122 may be made of a metal such as titanium (Ti), titanium nitride (TiN), tantalum nitride (TaN), aluminum (Al), or silver (Ag), or a multilayer film made by stacking these metals.

[0028] The plug 23 is provided in contact with the contact layer 122, and electrically connects the first electrode layer 12 and the drive substrate 30. The plug 23 is formed using, for example, copper (Cu), aluminum (Al), tungsten (W), silver (Ag), or an alloy thereof.

[0029] The buried layer 24 is provided between the protective film 15 and the drive substrate 30. The buried layer 24 is provided so as to bury the plug 21, the contact electrode layer 22, and the plug 23. The buried layer 24 is formed using, for example, silicon oxide (SiO), silicon nitride (SiN), silicon oxynitride (SiON), titanium oxide (TiO), or the like.

[0030] The drive substrate 30 is made of, for example, silicon (Si), etc. A drive circuit for driving the light emitting elements 11 is embedded in the drive substrate 30.

[0031] 1-2. Manufacturing Method] The light emitting device 1 of this embodiment can be manufactured, for example, as follows: Figures 3A to 3I show an example of a manufacturing process for the light emitting device 1.

[0032] 3A , for example, a sapphire substrate is prepared as a growth substrate 41, and then, for example, by epitaxial crystal growth, a first conductivity type layer 111, an active layer 112, and a second conductivity type layer 113 are formed in this order on the growth substrate 41. The epitaxial crystal growth can be performed using, for example, a metal organic chemical vapor deposition (MOCVD) method or a molecular beam epitaxy (MBE) method.

[0033] Next, the second electrode layer 13 is formed on the second conductivity type layer 113 to obtain the stacked film 110. Here, the second electrode layer 13 is formed so as to be in contact with the entire area of ​​the light emitting surface 11S. The second electrode layer 13 is obtained by forming a film of indium tin oxide using, for example, a sputtering method or a vapor deposition method.

[0034] Next, after the growth substrate 41 is peeled off, the stacked film 110 is inverted so that the second electrode layer 13 faces the support substrate 42, as shown in FIG. 3B, and the stacked film 110 is bonded to the support substrate 42. Next, a contact layer 122 and a reflective film 121 are formed in order to cover the surface of the first conductivity type layer 111 opposite the active layer 112, and an opening 121H is formed in the reflective film 121. This results in a first electrode layer 12. Next, a plug 21, contact electrode layers 22-1 and 22-2, and a plug 23 are formed in the buried layer 24. At this time, the plug 23 is provided so as to stand in the opening 121H of the reflective film 121. The plug 23 is formed so as to be connected to the contact layer 122. Furthermore, the contact electrode layer 22 is provided so as to be spaced apart from the first electrode layer 12. The plug 21 and the plug 23 are exposed on the back surface 24BS of the buried layer 24.

[0035] 3C, a separately manufactured drive substrate 30 is bonded to the back surface 24BS of the buried layer 24 (so-called hybrid bonding is performed), thereby connecting the drive substrate 30 to each of the plugs 21 and 23.

[0036] Next, the bonded stacked film 110, embedded layer 24, and drive substrate 30 are inverted so that the drive substrate 30 is on the bottom, and then the support substrate 42 is removed. After that, an insulating film 16 is formed using silicon oxide (SiO) or the like on the upper surface of the second electrode layer 13 that is exposed by removing the support substrate 42.

[0037] 3D, a hard mask HM, for example, is selectively provided in a predetermined region on the insulating film 16. For example, the hard mask HM is provided in a region overlapping the plug 23 in the Z-axis direction. Next, as shown in FIG. 3E, the hard mask HM is used to process the stacked film 110 and the second electrode layer 13 into a mesa shape by, for example, reactive ion etching (RIE). This operation results in a light-emitting element 11 consisting of a first conductivity type layer 111, an active layer 112, and a second conductivity type layer 113.

[0038] Next, the protective film 15 is formed so as to cover the end face 11S3 of the light emitting element 11, the upper surface of the insulating film 16, and the surface 24US of the embedded layer 24. Furthermore, the insulating film 160 is formed so as to cover the protective film 15.

[0039] Next, a resist is applied onto the insulating film 160 and then patterned by photolithography to form a resist pattern R1 as shown in Fig. 3F. The resist pattern R1 has an opening RH1 in a region corresponding to the contact electrode layer 22-1 in the Z-axis direction, and an opening RH2 in a region corresponding to the contact electrode layer 22-2 in the Z-axis direction.

[0040] Subsequently, for example, dry etching is performed using the resist pattern R1 as a mask to selectively remove the insulating film 160, the protective film 15, and the buried layer 24. As a result, an opening H1 is formed at a position corresponding to the contact electrode layer 22-1, and an opening H2 is formed at a position corresponding to the contact electrode layer 22-2, as shown in FIG.

[0041] 3H , the insulating film 16, a portion of the protective film 15, and a portion of the insulating film 160 are removed by, for example, CMP (Chemical Mechanical Polishing) so as to expose the upper surface of the second electrode layer 13. By this operation, a first insulating film 161 is obtained from the insulating film 160.

[0042] 3I, the transparent electrode 14 is formed so as to cover the entire area of ​​the upper surface 13S of the second electrode layer 13 and the first insulating film 161. The transparent electrode 14 is formed so as to continuously cover the entire area of ​​the light emitting surface 11S of the light emitting element 11 and the first insulating film 161, and to be electrically connected to each of the contact electrode layers 22-1 and 22-2. In this manner, the light emitting device 1 shown in FIG. 1 is completed.

[0043] [1-3. Functions and Effects] The light-emitting device 1 of the present embodiment includes a drive substrate 30, a light-emitting element 11, a contact electrode layer 22, and a transparent electrode 14. The light-emitting element 11 and the contact electrode layer 22 are each provided on the drive substrate 30. The contact electrode layer 22 includes a surface 22S1 located on the opposite side from the drive substrate 30. The transparent electrode 14 continuously covers the first insulating film 161, which covers the end face of the light-emitting element 11, the entire light-emitting surface 11S2 of the light-emitting element 11, and the first insulating film 161, and is electrically connected to the surface 22S1 of the contact electrode layer 22. In this way, in the light-emitting device 1, the transparent electrode 14 continuously covers the entire area of ​​the light-emitting surface 11S2 of the light-emitting element 11 and the first insulating film 161, thereby enabling emitted light to be extracted from the entire area of ​​the light-emitting surface 11S2 of the light-emitting element 11. That is, the light emitting device 1 can maximize the aperture area of ​​the light emitting element 11, and can maximize the aperture ratio of the light emitting element 11, i.e., the ratio of the area from which emitted light can be extracted to the area of ​​the light emitting surface 11S2. This will be described below.

[0044] Generally, in a light-emitting device including a mesa-shaped light-emitting element, as in the light-emitting device 1001 shown in Fig. 18 as a reference example, a transparent electrode 1014 having a stepped structure covers only a portion of the light-emitting surface 1011S2 of the light-emitting element 1011. In the light-emitting device 1001, a portion of the light-emitting surface 1011S2 is covered by the insulating film 1161, and therefore a portion of the light emitted from the light-emitting surface 1011S2 is blocked by the insulating film 1161. This reduces the aperture ratio of the light-emitting element 1011 (the ratio of the area through which emitted light can be extracted to the area of ​​the light-emitting surface 1011S2).

[0045] In contrast, in the light emitting device 1 of the present embodiment, as described above, the flat portion 141 of the transparent electrode 14 covers the entire area of ​​the second electrode layer 13, which covers the entire area of ​​the light emitting surface 11S2 of the light emitting element 11. Therefore, there is no component between the light emitting surface 11S2 of the light emitting element 11 and the transparent electrode 14 that blocks the light emitted from the light emitting surface 11S2, maximizing the aperture ratio of the light emitting element 11. Therefore, the light emitting efficiency of the light emitting device 1 is improved.

[0046] Furthermore, the transparent electrode 14 of the light-emitting element 11 of the light-emitting device 1 of the present embodiment has higher flatness than the transparent electrode 1014 of the light-emitting element 1011 of the light-emitting device 1001 that includes a transparent electrode having the above-described stepped structure. Therefore, the dimension (thickness) of the light-emitting element 11 in the Z-axis direction can be made smaller than the thickness of the light-emitting element 1011. Furthermore, since the transparent electrode 14 of the light-emitting element 11 has high flatness, it becomes easy to provide, for example, an on-chip lens or the like on the light-emitting surface 11S2 side of the light-emitting element 11.

[0047] 2. Second embodiment Fig. 4 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device 2 according to a second embodiment of the present disclosure. Fig. 5 is a schematic diagram illustrating an example of a planar configuration of the light-emitting device 2 illustrated in Fig. 4. The light-emitting device 2 is suitably applicable to an image display device known as an LED display (for example, the image display device 100 illustrated in Fig. 21 described below).

[0048] [2-1. Configuration] In the light-emitting device 1 of the first embodiment, the transparent electrode 14 has a step from the light-emitting surface 11S2 of the light-emitting element 11 to the surface 22S1 of the contact electrode layer 22. Furthermore, the first insulating film 161 has a corner on the surface connecting the end surface 11S3 of the light-emitting element 11 and the light-emitting surface 11S2 of the light-emitting element 11. In contrast, in the second embodiment, the first insulating film 161A includes a side surface that is continuous from the light-emitting surface 11S2 of the light-emitting element 11 to the surface 22S1 of the contact electrode layer 22A. Furthermore, in the second embodiment, the side surface 161S of the first insulating film 161A includes a flat portion 161S1 extending along the end surface 11S3 of the light-emitting element 11 and a curved portion 161S2 connecting the flat portion 161S1 and the light-emitting surface 11S2 of the light-emitting element 11.

[0049] The transparent electrode 14A has a smooth structure without any steps from the light emitting surface 11S2 of the light emitting element 11 to the surface 22S1 of the contact electrode layer 22A. That is, the transparent electrode 14A has no bending points or inflection points from the light emitting surface 11S2 of the light emitting element 11 to the surface 22S of the contact electrode layer 22A, and has a conformal shape that follows the outer shape of the light emitting element 11.

[0050] The contact electrode layer 22A includes an opening 22AH along the outer edge of the light-emitting element 11. As shown in FIG. 5 , the contact electrode layer 22A is provided in contact with the transparent electrode 14A in a ring-like shape in a plan view. That is, the bonding region F1 between the contact electrode layer 22A and the transparent electrode 14A is provided so as to surround at least a portion of the light-emitting element 11 in a plan view. Note that FIG. 5 shows an example in which the bonding region F1 is provided in a ring-like shape, but the planar shape of the bonding region F1 is not limited to a ring-like shape and may be other shapes. Furthermore, the planar shape of the bonding region F1 is not limited to a ring-like shape and may be a semi-ring-like shape in which a notch is provided in a portion of the region surrounding the periphery of the light-emitting element 11.

[0051] Except for the above points, the light emitting device has substantially the same configuration as the light emitting device 1 according to the first embodiment.

[0052] [2-2. Manufacturing Method] The light emitting device 2 of the present embodiment can be manufactured, for example, as follows. The manufacturing process up to the step of forming the insulating film 160 shown in Figures 3A to 3E is the same as the manufacturing process of the light emitting device 1. Figures 6A to 6C show an example of the manufacturing process of the light emitting device 2 after the formation of the insulating film 160.

[0053] First, a resist is applied onto the insulating film 160, and then the resist is patterned by photolithography to form a resist pattern R2 shown in Fig. 6A. The resist pattern R2 has a substantially circular opening RH3 with the light emitting element 11 at its center in a plan view.

[0054] Next, the insulating film 160, the protective film 15, and the embedded layer 24 are selectively removed by dry etching using, for example, the resist pattern R2 as a mask. This forms an opening H3 as shown in FIG. 6B . This operation exposes the contact electrode layer 22A in a ring shape in a plan view. Furthermore, for example, dry etching is used to form the first insulating film 161A so as to have a flat portion 161S1 extending along the end surface 11S3 of the light-emitting element 11 and a curved portion 161S2 connecting the flat portion 161S1 and the light-emitting surface 11S2 of the light-emitting element 11, as shown in FIG. 6B .

[0055] 6C, the transparent electrode 14A is formed so as to continuously cover the entire area of ​​the light emitting surface 11S2 of the light emitting element 11 and the first insulating film 161A, and to be electrically connected to the contact electrode layer 22A. In this way, the light emitting device 2 shown in FIG.

[0056] [2-3. Actions and Effects] The light emitting device 2 of the present embodiment also provides the same effects as the light emitting device 1 of the first embodiment. That is, the aperture area of ​​the light emitting element 11 can be maximized, and the aperture ratio of the light emitting element 11, i.e., the ratio of the area from which emitted light can be extracted to the area of ​​the light emitting surface 11S2, can be maximized.

[0057] In the light-emitting device 2 of this embodiment, in addition to the configuration of the light-emitting device 1 of the above embodiment, the first insulating film 161A includes a side surface that continues from the light-emitting surface 11S2 of the light-emitting element 11 to the surface 22S1 of the contact electrode layer 22A. Furthermore, in the light-emitting device 2, the side surface 161S of the first insulating film 161A includes a flat portion 161S1 extending along the end surface 11S3 of the light-emitting element 11 and a curved portion 161S2 connecting the flat portion 161S1 and the light-emitting surface 11S2 of the light-emitting element 11. The transparent electrode 14A has a conformal shape that follows the outer shape of the light-emitting element 11 from the light-emitting surface 11S2 of the light-emitting element 11 to the surface 22S of the contact electrode layer 22A. This improves the layout efficiency of the light-emitting device 2. The transparent electrode 14A has a curved portion that follows the outer shape of the curved portion 161S2 of the first insulating film 161A, thereby reducing thickness variations in the transparent electrode 14A. This can prevent breakage of the transparent electrode 14A and an increase in the electrical resistance value, thereby improving the reliability and performance of the light emitting device 2.

[0058] In the light emitting device 2 of the present embodiment, the contact electrode layer 22A is further provided in a ring shape so as to surround the periphery of the light emitting element 11 in a plan view. Therefore, the distance in the in-plane direction between the light emitting element 11 and the contact electrode layer 22A is shorter than the distance in the in-plane direction between the light emitting element and the contact electrode layer of a general light emitting device. This enables high integration of the plurality of light emitting elements 11 in the light emitting device 2 including the plurality of light emitting elements 11.

[0059] 3. Modifications of the First and Second Embodiments Next, we will explain Modifications 1 to 5 of the present disclosure. Note that components corresponding to the light emitting device 1 of the first embodiment and the light emitting device 2 of the second embodiment are given the same reference numerals, and their explanations will be omitted.

[0060] [3-1. Modification 1] FIG. 7 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device 3 according to Modification 1 of the present disclosure.

[0061] In the second embodiment described above, an example was shown in which the first insulating film 161A was provided between the transparent electrode 14A and the protective film 15, but the present disclosure is not limited to this. In the light emitting device 3 of this modification, a second insulating film 162 is further provided between the first insulating film 161A and the transparent electrode 14A. Except for the above points, the configuration of the light emitting device 3 is substantially the same as the configuration of the light emitting device 2 of the second embodiment described above.

[0062] The etching resistance of the second insulating film 162 is different from that of the first insulating film 161. That is, the etching rate of the second insulating film 162 is different from that of the first insulating film 161. For example, the etching resistance of the second insulating film 162 is higher than that of the first insulating film 161, and therefore the etching rate of the second insulating film 162 is lower than that of the first insulating film 161. The second insulating film 162 is formed using, for example, at least one of SiO2, SiN, SiON, P(plasma)-TEOS, and silicon-rich oxide. The method for forming the second insulating film 162 may be different from that for forming the first insulating film 161. Therefore, for example, the film quality of the second insulating film 162 may be different from that of the first insulating film 161. The second insulating film 162 can be formed by, for example, a sputtering method or an ALD method. The second insulating film 162 may have, for example, a multilayer film structure having two or more layers. The second insulating film 162 may be light-reflective. When manufacturing the light-emitting device 3 of this modified example, an insulating film 160 (see FIG. 6A ), which will eventually become the first insulating film 161, is formed. A second insulating film 162 is then formed to cover the insulating film 160, and a resist pattern R2 is then formed. The subsequent manufacturing steps are the same as those for the light-emitting device 2 of the second embodiment. For example, dry etching is performed using the resist pattern R2 as a mask to selectively remove the insulating film 160, the second insulating film 162, the protective film 15, and the embedded layer 24, thereby forming an opening H3. Furthermore, by performing dry etching, for example, the second insulating film 162 is formed to have a flat portion 162S1 extending along the end surface 11S3 of the light-emitting element 11 and a curved portion 162S2 extending from the flat portion 162S1 toward the light-emitting surface 11S2 of the light-emitting element 11, as shown in FIG. 7 .

[0063] In the light emitting device 3 of this modified example, the second insulating film 162 is provided between the first insulating film 161 and the transparent electrode 14. This makes it possible to reliably leave the first insulating film 161 and the second insulating film 162 covering the end surface 11S3 of the light emitting element 11 with a sufficient thickness when, for example, dry etching is performed using a resist to expose the upper surface of the second electrode layer 13 and form the opening H3 in the manufacturing process. Covering the end surface 11S3 of the light emitting element 11 with the first insulating film 161 and the second insulating film 162 with a sufficient thickness more reliably ensures the insulation of the light emitting element 11.

[0064] 3-2. Modification 2 FIG. 8 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device 4 according to Modification 2 of the present disclosure.

[0065] In the first embodiment, the transparent electrode 14 is in contact with the contact electrode layer 22 to electrically connect the light emitting element 11, but the present disclosure is not limited to this. In the light emitting device 4 of this modified example, a plug 25 is further provided to electrically connect the contact electrode layer 22 and the transparent electrode 14B. This reduces the step portion of the transparent electrode 14B compared to the transparent electrode 14, and achieves higher flatness.

[0066] Except for the above points, the configuration of the light emitting device 4 is substantially the same as the configuration of the light emitting device 1 of the first embodiment. Even with this configuration, the light emitting device 4 can obtain the same effects as the light emitting device 1 of the first embodiment.

[0067] 3-3. Modification 3 FIG. 9 is a schematic diagram illustrating an example of a planar configuration of a light-emitting device 5 according to Modification 3 of the present disclosure.

[0068] In the second embodiment, the contact electrode layer 22 has a substantially rectangular shape in a plan view and is in contact with the transparent electrode 14A in a circular ring shape, but the present disclosure is not limited to this. In the light-emitting device 4 of this modification, the contact electrode layer 22C has a substantially circular shape.

[0069] Except for the above points, the configuration of the light emitting device 4 is substantially the same as the configuration of the light emitting device 2 of the second embodiment. Even with this configuration, the light emitting device 4 can achieve the same effects as the light emitting device 2 of the second embodiment.

[0070] [3-4. Modification 4] Fig. 10A is a schematic diagram showing an example of the planar configuration of a light-emitting device 6-1 according to Modification 4 of the present disclosure. Fig. 10B is a schematic diagram showing an example of the planar configuration of a light-emitting device 6-2 according to Modification 4 of the present disclosure. Fig. 10C is a schematic diagram showing another example of the planar configuration of a light-emitting device 6-3 according to Modification 4 of the present disclosure.

[0071] In the second embodiment, the bonding region F1 between the contact electrode layer 22A and the transparent electrode 14A is annular in plan view, centered around the light-emitting element 11, but the present disclosure is not limited thereto. In the light-emitting device 6-1 of this modification, as shown in FIG. 10A, the center of the bonding region F1 between the contact electrode layer 22A and the transparent electrode 14A does not have to coincide with the center of the light-emitting element 11. In the light-emitting device 6-2 of this modification, as shown in FIG. 10B, the bonding region F2 between the contact electrode layer 22A and the transparent electrode 14A may have a shape that combines a substantially circular shape with a substantially rectangular shape. In the light-emitting device 6-3 of this modification, as shown in FIG. 10C, the bonding region F3 between the contact electrode layer 22A and the transparent electrode 14A may have a substantially rectangular shape that includes a portion of the light-emitting element 11.

[0072] Except for the above points, the configuration of the light emitting device 6 is substantially the same as the configuration of the light emitting device 2 of the second embodiment. Even with this configuration, the light emitting device 6 can obtain the same effects as those of the second embodiment.

[0073] 3-5. Modification 5 FIG. 11 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device 7 according to Modification 5 of the present disclosure.

[0074] In the first and second embodiments described above, an example has been shown in which the end surface 11S3 of the light-emitting element 11 is inclined at an angle of less than 90° with respect to the surface of the drive substrate 30, but the present disclosure is not limited to this. As in the light-emitting device 7 of this modified example, the end surface 11FS3 of the light-emitting element 11F may be perpendicular to the surface of the drive substrate 30.

[0075] Except for the above points, the configuration of the light emitting device 7 is substantially the same as the configuration of the light emitting device 1 of the first embodiment and the light emitting device 2 of the second embodiment. Even with this configuration, the light emitting device 7 can achieve the same effects as the light emitting device 1 of the first embodiment and the light emitting device 2 of the second embodiment.

[0076] 4. Third Embodiment Fig. 12 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device 8 according to a third embodiment of the present disclosure. Fig. 13 is a schematic diagram illustrating an example of a planar configuration of the light-emitting device 8 illustrated in Fig. 12. However, in Fig. 13, some components such as the transparent electrode 14 are omitted. Fig. 12 illustrates a cross section viewed in the direction of the arrows along line XII-XII illustrated in Fig. 13. The light-emitting device 8 is suitably applicable to an image display device known as an LED display (for example, the image display device 100 illustrated in Fig. 21 below).

[0077] 12 and 13, the light emitting device 8 further includes a heat dissipation portion 50 and a heat conduction path 60. Except for the above points, the light emitting device 8 has substantially the same configuration as the light emitting device 1 according to the first embodiment.

[0078] The heat dissipation section 50 is provided in a region AR50 of the drive substrate 30 in the XY plane, which is different from both the region AR11 in which the light emitting element 11 is provided and the region AR21 in which the plug 21 connected to the contact electrode layer 22 is provided. The heat dissipation section 50 is, for example, a portion that dissipates heat generated by the light emitting element 11, and may have a thermal conductivity higher than that of the protective film 15 and the embedded layer 24. The heat dissipation section 50 may contain, for example, the same constituent material as that of the light emitting element 11. More specifically, it may be formed from the same constituent material as that of the first conductivity type layer 111, for example, a GaN-based semiconductor material. The heat dissipation section 50 may be provided in the same layer as the light emitting element 11. Providing the heat dissipation section 50 in the same layer as the light emitting element 11 means that at least a portion of the heat dissipation section 50 is positioned so as to overlap a portion of the light emitting element 11 in the XY plane.

[0079] 14 is an enlarged cross-sectional view of the heat dissipation unit 50 shown in FIG. 12. The heat dissipation unit 50 includes a plurality of acicular protrusions 51 each extending in the Z-axis direction, which corresponds to the thickness direction of the light emitting element 11. A minute oxide 52 is attached to the tip of each of the acicular protrusions 51. If the material constituting the plurality of acicular protrusions 51 is, for example, a GaN-based semiconductor material, the oxide 52 is, for example, GaO (gallium oxide). As shown in FIG. 14, the height H of each acicular protrusion 51 along the Z-axis direction of the light emitting element 11 is preferably greater than the diameter D of each acicular protrusion 51.

[0080] The heat conduction path 60 covers the end surface 11S3 of the light emitting element 11 via the protective film 15 and is connected to the heat dissipation portion 50. The heat conduction path 60 has a thermal conductivity higher than that of the protective film 15. The heat conduction path 60 may be formed of a metal containing at least one of, for example, Ag (silver), Cu (copper), Au (gold), Al (aluminum), Mg (magnesium), Zn (zinc), Fe (iron), W (tungsten), Sn (tin), Pb (lead), Ga (gallium), and Pt (platinum).

[0081] [4-2. Manufacturing Method] The light emitting device 8 of the present embodiment can be manufactured, for example, as follows. A manufacturing method for the light emitting device 8 will be described with reference to Figures 15A to 15I in addition to Figures 3A to 3C. Figures 15A to 15I show an example of a manufacturing process for the light emitting device 8.

[0082] 3A to 3C, a structure in which the embedded layer 24, the first electrode layer 12, the stacked film 110, the second electrode layer 13, and the insulating film 16 are stacked in this order on the drive substrate 30. The embedded layer 24 is filled with the plug 21, the contact electrode layers 22-1 and 22-2, the plug 23, and the like.

[0083] 15A, a hard mask HM is selectively provided in regions AR11 and AR50 on the insulating film 16. The region AR11 is a region where the light emitting element 11 will be provided, and the region AR50 is a region where the heat dissipation portion 50 will be provided. Next, as shown in FIG. 15B, the hard mask HM is used to selectively remove the insulating film 16, the second electrode layer 13, and the stacked film 110 by, for example, reactive ion etching. This operation results in stacked bodies 11Z and 50Z, each consisting of a first conductivity type layer 111, an active layer 112, and a second conductivity type layer 113.

[0084] 15C, a protective film 15 is formed to cover the stacked bodies 11Z and 50Z, the insulating film 16, and the surface 24US of the embedded layer 24. After that, a heat conduction path 60 is selectively formed in a portion of the protective film 15 in an area excluding the areas AR11, AR21, and AR50. Furthermore, an insulating film 160 is formed to cover the protective film 15 and the heat conduction path 60, as shown in FIG.

[0085] Next, dry etching is performed using a resist pattern formed by, for example, photolithography as a mask to selectively remove the insulating film 160, the protective film 15, and the embedded layer 24 in the region AR21, thereby forming an opening H1 at a position corresponding to the contact electrode layer 22-1 as shown in FIG.

[0086] 15F , the insulating film 16, a portion of the protective film 15, and a portion of the insulating film 160 are removed by, for example, CMP so as to expose the upper surface of the second electrode layer 13. By this operation, the light emitting element 11 and the first insulating film 161 are obtained.

[0087] 15G, a transparent electrode 14 is formed so as to cover the entire area of ​​the upper surface 13S of the second electrode layer 13 of the light-emitting element 11, the first insulating film 161, and the contact electrode layer 22-1. However, the laminate 50Z is not covered with the transparent electrode 14, and the upper surface of the laminate 50Z is exposed. The transparent electrode 14 is formed so as to continuously cover the entire area of ​​the light-emitting surface 11S of the light-emitting element 11 and the first insulating film 161, and to be electrically connected to the contact electrode layer 22-1.

[0088] 15H, a resist pattern RP is formed to cover the region excluding region AR50. Thereafter, reactive ion etching is performed on the laminate 50Z exposed in region AR50, thereby obtaining a heat dissipation portion 50 having a plurality of needle-like protrusions 51. The shape and density of the plurality of needle-like protrusions 51 can be adjusted by adjusting the type and pressure of the etching gas used in the reactive ion etching, the plasma density, the RF power, the ambient temperature, and the like. When reactive ion etching is performed on the laminate 50Z, it is preferable to form a plurality of minute oxides 52 so that the oxides 52 serve as an etching mask.

[0089] In this way, the light emitting device 8 shown in FIG. 12 is completed.

[0090] [4-3. Actions and Effects] The light emitting device 8 of the present embodiment also provides the same effects as the light emitting device 1 of the first embodiment. That is, the aperture area of ​​the light emitting element 11 can be maximized, and the aperture ratio of the light emitting element 11, i.e., the ratio of the area from which emitted light can be extracted to the area of ​​the light emitting surface 11S2, can be maximized.

[0091] The light-emitting device 8 of the present embodiment further includes a heat dissipation unit 50 and a heat conduction path 60 in addition to the configuration of the light-emitting device 1 of the above embodiment. Therefore, for example, heat generated in the light-emitting element 11 during light emission can be quickly dissipated from the heat dissipation unit 50 to the outside via the heat conduction path 60. In particular, since the heat dissipation unit 50 has multiple needle-like protrusions 51, the surface area of ​​the heat dissipation unit 50 can be increased without increasing the area occupied by the heat dissipation unit 50 in the XY plane. Therefore, the light-emitting device 8 can dissipate heat from the light-emitting element 11 more efficiently than when the heat dissipation unit 50 does not have multiple needle-like protrusions 51. When the light-emitting element 11 becomes hot, the elements constituting the first conductivity-type layer 111, the active layer 112, and the second conductivity-type layer 113 may diffuse to the surroundings, resulting in a decrease in light-emitting efficiency. According to the light-emitting device 8 of this embodiment, a heat dissipation section 50 and a heat conduction path 60 are provided, which reduces the temperature rise of the light-emitting element 11 and its surrounding area, thereby suppressing a decrease in the light-emitting performance of the light-emitting element 11.

[0092] [4-4. Modifications] Next, a description will be given of modifications 6 to 10 of the present disclosure. Note that components corresponding to those of the light emitting device 8 of the above embodiment are given the same reference numerals, and description thereof will be omitted.

[0093] 16 is a schematic diagram illustrating an example of a cross-sectional configuration of a light emitting device 8A according to Modification 6 of the present disclosure. In the light emitting device 8A of Modification 6, a filling layer 53 is further provided in the heat dissipation section 50. Except for the above points, the configuration of the light emitting device 8A of Modification 6 is substantially the same as the configuration of the light emitting device 8 of the third embodiment described above.

[0094] The filling layer 53 fills the gaps between the multiple needle-like projections 51. The filling layer 53 preferably has a high thermal conductivity equal to or higher than that of the heat dissipation section 50. The upper surface 50S of the filling layer 53 is preferably a flat surface. By providing the filling layer 53, the shape of the multiple needle-like projections 51 is stably maintained. Furthermore, by providing the filling layer 53, further improvement in heat dissipation efficiency can be expected.

[0095] 17 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device 8B according to Modification 7 of the present disclosure. The light-emitting device 8B of Modification 7 is further provided with a metal coating 54 that covers the multiple needle-like protrusions 51 of the heat dissipation portion 50. Except for the above points, the configuration of the light-emitting device 8B of Modification 7 is substantially the same as the configuration of the light-emitting device 8 of the third embodiment described above.

[0096] The metal coating 54 is provided so as to cover the tips and side surfaces of the multiple needle-like protrusions 51. The metal coating 54 is preferably made of a metal material having a high thermal conductivity equal to or higher than that of the heat dissipation unit 50. The metal coating 54 may be in direct contact with the heat conduction path 60. The metal coating 54 can be formed by, for example, a chemical vapor deposition (CVD) method or an atomic layer deposition (ALD) method. By providing the metal coating 54, the shape of the multiple needle-like protrusions 51 is stably maintained. Furthermore, by providing the metal coating 54, further improvement in heat dissipation efficiency can be expected.

[0097] 18 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device 8C according to Modification 8 of the present disclosure. In the light-emitting device 8C of Modification 8, a lens layer 71 made of a transparent material is further provided so as to cover the light-emitting element 11. Except for the above points, the configuration of the light-emitting device 8C of Modification 8 is substantially the same as the configuration of the light-emitting device 8 of the third embodiment described above.

[0098] 19 is a schematic diagram illustrating an example of a cross-sectional configuration of a light emitting device 8D according to Modification 9 of the present disclosure. In light emitting device 8D of Modification 9, heat conduction path 60 may extend through heat dissipation portion 50 to connection terminal 61 that is connected to an external device.

[0099] (4-4-5. Modification 10) In the present disclosure, the arrangement position of the heat dissipation unit 50 is not limited to the arrangement shown in FIG. 13. FIG. 20 is a schematic diagram showing an example of the planar configuration of a light-emitting device 8E according to Modification 10 of the present disclosure. As in the light-emitting device 8E of Modification 10, the heat dissipation unit 50 may also be provided between adjacent light-emitting elements 11. Except for the above points, the configuration of the light-emitting device 8E of Modification 8 is substantially the same as the configuration of the light-emitting device 8 of the third embodiment described above.

[0100] According to the light emitting device 8E of the tenth modification, the distance between the heat dissipation section 50 and the light emitting element 11 is shortened, so that further improvement in heat dissipation efficiency can be expected.

[0101] The heat dissipation section 50 may also be used as a wiring layer, in which case the heat dissipation section 50 may be electrically connected to a connection terminal for connecting to an external circuit.

[0102] Furthermore, in the light emitting devices 8, 8A to 8E, the three-dimensional shape of the light emitting element 11 is not limited to a substantially truncated cone shape, but may be, for example, a substantially polygonal prism shape, a substantially cylindrical shape, or a substantially polygonal pyramid shape.

[0103] 21 is a perspective view showing an example of a schematic configuration of an image display device (image display device 100). The image display device 100 is a so-called LED display, and uses a light-emitting device according to the present disclosure (e.g., light-emitting device 1) as a display pixel. As shown in FIG. 21 , the image display device 100 includes a display panel 120 and a control circuit 140 that drives the display panel 120.

[0104] The display panel 120 is formed by stacking a mounting substrate 120A and an opposing substrate 120B. The surface of the opposing substrate 120B serves as an image display surface, with a display area (display section 100A) in the center and a frame section 100B, which is a non-display area, around the display area.

[0105] 22 shows an example of a wiring layout in a region of the surface of the mounting substrate 120A facing the counter substrate 120B, which corresponds to the display unit 100A. In the region of the surface of the mounting substrate 120A corresponding to the display unit 100A, a plurality of data wirings 134 are formed extending in a predetermined direction and arranged in parallel at a predetermined pitch, as shown in FIG. 22 . In the region of the surface of the mounting substrate 120A corresponding to the display unit 100A, a plurality of scan wirings 135 are further formed extending in a direction intersecting (e.g., perpendicular to) the data wirings 134 and arranged in parallel at a predetermined pitch. The data wirings 134 and the scan wirings 135 are made of a conductive material, such as Cu.

[0106] The scan lines 135 are formed, for example, in the outermost layer, for example, on an insulating layer (not shown) formed on the surface of the substrate. The substrate of the mounting board 120A is made of, for example, a silicon substrate or a resin substrate, and the insulating layer on the substrate is made of, for example, SiN, SiO, aluminum oxide (AlO), or a resin material. On the other hand, the data lines 134 are formed in a layer different from the outermost layer including the scan lines 135 (for example, a layer below the outermost layer), for example, in an insulating layer on the substrate.

[0107] The display pixels 136 are located near the intersections of the data lines 134 and the scan lines 135, and a plurality of the display pixels 136 are arranged in a matrix within the display unit 100A. Each of the display pixels 136 is equipped with, for example, one of the color pixels Pr, Pg, and Pb of the light-emitting device 1.

[0108] The light-emitting device 1 is provided with a pair of terminal electrodes, for example, one for each of the color pixels Pr, Pg, and Pb, or one common and the other for each of the color pixels Pr, Pg, and Pb. One of the terminal electrodes is electrically connected to a data wiring 134, and the other is electrically connected to a scan wiring 135. For example, one of the terminal electrodes is electrically connected to a pad electrode 134B at the tip of a branch 134A provided on the data wiring 134. Furthermore, for example, the other terminal electrode is electrically connected to a pad electrode 135B at the tip of a branch 135A provided on the scan wiring 135.

[0109] Each of the pad electrodes 134B, 135B is formed, for example, on the outermost layer and is provided at a location where each of the light emitting devices 1 is mounted, as shown in Fig. 13. Here, the pad electrodes 134B, 135B are made of a conductive material such as Au (gold).

[0110] The mounting substrate 120A is further provided with, for example, a plurality of support pillars (not shown) that regulate the distance between the mounting substrate 120A and the counter substrate 120B. The support pillars may be provided in the region facing the display unit 100A, or in the region facing the frame unit 100B.

[0111] The counter substrate 120B is made of, for example, a glass substrate or a resin substrate. The surface of the counter substrate 120B facing the light-emitting device 1 may be flat, but is preferably roughened. The roughened surface may be provided over the entire area facing the display unit 100A, or may be provided only in the area facing the display pixels 136. The roughened surface has fine irregularities that allow light emitted from the color pixels Pr, Pg, and Pb to enter the roughened surface. The irregularities on the roughened surface can be created by, for example, sandblasting or dry etching.

[0112] The control circuit 140 drives each display pixel 136 (each light-emitting device 1) based on a video signal. The control circuit 140 is configured, for example, with a data driver that drives the data wiring 134 connected to the display pixels 136 and a scan driver that drives the scan wiring 135 connected to the display pixels 136. For example, as shown in FIG. 22 , the control circuit 140 may be provided separately from the display panel 120 and connected to the mounting substrate 120A via wiring, or may be mounted on the mounting substrate 120A.

[0113] 23 is a perspective view showing another configuration example (image display device 200) of an image display device using a light-emitting device (e.g., light-emitting device 1) according to the present disclosure. The image display device 200 is a so-called tiling display that uses a plurality of light-emitting devices that use LEDs as light sources. As shown in FIG. 23 , the image display device 200 includes, for example, a display panel 220 and a control circuit 240 that drives the display panel 220.

[0114] The display panel 220 is formed by stacking a mounting substrate 220A and a counter substrate 220B on top of each other. The surface of the counter substrate 220B serves as an image display surface, with a display section in the center and a frame section surrounding the display section, which is a non-display area (neither of which is shown). The counter substrate 220B is disposed, for example, in a position opposite the mounting substrate 220A with a predetermined gap therebetween. Note that the counter substrate 220B may also be in contact with the top surface of the mounting substrate 220A.

[0115] Fig. 24 is a schematic diagram showing an example of the configuration of the mounting substrate 220A. For example, as shown in Fig. 24, the mounting substrate 220A is configured from a plurality of unit substrates 250 arranged in a tiled pattern. Note that Fig. 24 shows an example in which the mounting substrate 220A is configured from nine unit substrates 250, but the number of unit substrates 250 may be ten or more, or eight or less.

[0116] 25 shows an example of the configuration of a unit substrate 250. The unit substrate 250 has, for example, a plurality of light-emitting devices 1 arranged in a tiled pattern and a support substrate 260 that supports each of the light-emitting devices 1. Each unit substrate 250 also has a control substrate (not shown). The support substrate 260 is made of, for example, a metal frame (metal plate) or a wiring substrate. If the support substrate 260 is made of a wiring substrate, it can also serve as the control substrate. In this case, at least one of the support substrate 260 and the control substrate is electrically connected to each of the light-emitting devices 1.

[0117] 26 shows the appearance of a transparent display 300. The transparent display 300 includes, for example, a display unit 310, an operation unit 311, and a housing 312. The display unit 310 uses a light-emitting device (for example, the light-emitting device 1) according to the present disclosure. The transparent display 300 can display images and text information while allowing the background of the display unit 310 to be seen through.

[0118] In the transparent display 300, a light-transmitting substrate is used as the mounting substrate. Each electrode provided in the light-emitting device 1 is formed using a light-transmitting conductive material, similar to the mounting substrate. Alternatively, each electrode is structured to be less visible by increasing the wiring width or reducing the wiring thickness. Furthermore, the transparent display 300 can display black by, for example, overlaying a liquid crystal layer equipped with a drive circuit, and switching between transparent and black display is possible by controlling the light distribution direction of the liquid crystal.

[0119] Although the present technology has been described above with reference to the embodiments, Modifications 1 to 5, and application examples, the present technology is not limited to the above embodiments, etc., and various modifications are possible. For example, in the above embodiments, etc., examples have been shown in which the light emitted from the light-emitting element 11 is blue light or ultraviolet light, but the present technology is not limited to this. For example, the light-emitting device 1 may use a light-emitting element that emits two or more types of light, such as blue light and green light, or ultraviolet light and green light.

[0120] In addition, in the above-described embodiment, each component constituting the light emitting device 1 etc. has been specifically listed and described, but it is not necessary to include all components, and other components may also be included.

[0121] In addition, although the above-described embodiments and the like have exemplified the case where light-emitting elements and the like are provided on a drive substrate having a drive circuit, the present disclosure is not limited to this. For example, light-emitting elements and the like may be provided on another substrate that does not have a drive circuit, and the light-emitting elements may be connected to a drive circuit included in a drive substrate separate from the other substrate.

[0122] The effects described in this specification are merely examples and are not limited to those described, and other effects may also be obtained.

[0123] The present technology can also be configured as follows. According to the present technology configured as follows, there is no component between the light-emitting surface of the light-emitting element and the transparent electrode that blocks emitted light, thereby maximizing the aperture ratio of the light-emitting element. This makes it possible to improve the light-emitting efficiency of the light-emitting device. (1) A light-emitting device comprising: a substrate; a light-emitting element provided on the substrate, the light-emitting element including a facing surface facing the substrate, a light-emitting surface opposite the facing surface, and an end surface connecting the facing surface and the light-emitting surface; an electrode layer in contact with the entire area of ​​the light-emitting surface; a contact electrode layer provided in a second area of ​​the substrate different from a first area in which the light-emitting element is provided, the contact electrode layer including a surface located opposite the substrate; a first insulating film covering the end surface of the light-emitting element; and a transparent electrode continuously covering the entire area of ​​the electrode layer and the first insulating film and electrically connected to the surface of the contact electrode layer, wherein the only portion of the transparent electrode that covers the entire area of ​​the electrode layer is a flat portion that extends along the light-emitting surface. (2) The light-emitting device according to (1), wherein the light-emitting surface of the light-emitting element is a flat surface. (3) The light-emitting device according to (1) or (2), wherein the first insulating film includes a side surface that is continuous from the light-emitting surface of the light-emitting element to the surface of the contact electrode layer. (4) The light-emitting device according to (3), wherein the side surface of the first insulating film includes a flat portion extending along the end face of the light-emitting element and a curved portion connecting the flat portion and the light-emitting surface of the light-emitting element. (5) The light-emitting device according to any one of (1) to (4), wherein the contact electrode layer includes an opening along an outer edge of the light-emitting element. (6) The light-emitting device according to (5), wherein a junction region between the contact electrode layer and the transparent electrode is provided so as to surround at least a portion of the light-emitting element in a plan view. (7) The light-emitting device according to any one of (1) to (6), wherein the light-emitting element includes a first conductivity type layer, an active layer, and a second conductivity type layer, in this order from the substrate side. (8) The light-emitting device according to (7), wherein the first conductivity type layer is formed of an n-type GaN-based semiconductor material, and the second conductivity type layer is formed of a p-type GaN-based semiconductor material.(9) The light-emitting device according to any one of (1) to (8), further comprising a protective film between the end face of the light-emitting element and the first insulating film. (10) The light-emitting device according to (9), wherein the protective film is formed using at least one of aluminum oxide, titanium nitride, and resin. (11) The light-emitting device according to any one of (1) to (10), wherein the first insulating film is formed using at least one of SiO, SiN, and P-TEOS. (12) The light-emitting device according to any one of (1) to (11), further comprising a second insulating film between the first insulating film and the transparent electrode. (13) The light-emitting device according to (12), wherein the second insulating film has a multilayer film structure having two or more layers. (14) The light-emitting device according to (12) or (13), wherein the etching rate of the second insulating film is different from the etching rate of the first insulating film. (15) The second insulating film is formed using SiO. ２, SiN, SiON, P-TEOS, and silicon-rich oxide. (16) The light-emitting device according to any one of (1) to (15), further comprising: a heat dissipation portion provided in a third region of the substrate different from a first region in which the light-emitting element is provided, the heat dissipation portion having a thermal conductivity higher than that of the first insulating film; and a heat conduction path covering the end face of the light-emitting element via the first insulating film and connected to the heat dissipation portion, the heat dissipation portion having a thermal conductivity higher than that of the first insulating film. (17) The light-emitting device according to (16), wherein the heat dissipation portion includes a plurality of needle-like protrusions each extending in a thickness direction of the light-emitting element. (18) The light-emitting device according to (17), wherein the height of the needle-like protrusions in the thickness direction of the light-emitting element is greater than the diameter of the needle-like protrusions. (19) The light-emitting device according to any one of (16) to (18), wherein the heat dissipation portion is provided in the same layer as the light-emitting element and includes a constituent material of the light-emitting element. (20) The light-emitting device according to any one of (16) to (19), wherein the heat conduction path is made of a metal containing at least one of Ag (silver), Cu (copper), Au (gold), Al (aluminum), Mg (magnesium), Zn (zinc), Fe (iron), W (tungsten), Sn (tin), Pb (lead), Ga (gallium), and Pt (platinum). (21) A light emitting device comprising: a substrate, one or more light emitting elements provided on the substrate and including a facing surface facing the substrate, a light emitting surface opposite the facing surface, and an end surface connecting the facing surface and the light emitting surface, a first insulating film covering the end surfaces of the one or more light emitting elements, a heat dissipation section provided in an area of ​​the substrate different from an area where the one or more light emitting elements are provided, and having a thermal conductivity higher than that of the first insulating film, and a heat conduction path covering the end surfaces of the one or more light emitting elements via the first insulating film and connected to the heat dissipation section. (22) The light emitting device according to (21), wherein the one or more light emitting elements are a plurality of light emitting elements, and the heat dissipation section is provided between the plurality of light emitting elements.(23) A method for manufacturing a light-emitting device, comprising: forming a contact electrode layer and a light-emitting element having a light-emitting surface on a substrate opposite to the substrate; covering the contact electrode layer and the light-emitting element with an insulating film; selectively etching the insulating film to expose the entire area of ​​the light-emitting surface and at least a part of the contact electrode layer; and forming a transparent electrode to continuously cover the entire area of ​​the light-emitting surface of the light-emitting element and the insulating film and to be electrically connected to the contact electrode layer. (24) A method for manufacturing a light-emitting device according to (23), further comprising providing an electrode layer to be in contact with the entire area of ​​the light-emitting surface, and forming the transparent electrode to cover the entire area of ​​the electrode layer. (25) A method for manufacturing a light-emitting device according to (23) or (24), further comprising selectively etching the insulating film so that the contact electrode layer is exposed in a ring shape in a plan view. (26) An image display device comprising a light-emitting device comprising: a substrate; a light-emitting element provided on the substrate and including an opposing surface facing the substrate, a light-emitting surface opposite the opposing surface, and an end surface connecting the opposing surface and the light-emitting surface; an electrode layer in contact with the entire area of ​​the light-emitting surface; a contact electrode layer provided on the substrate at a position different from the position at which the light-emitting element is provided and including a surface located opposite the substrate; a first insulating film covering the end surface of the light-emitting element; and a transparent electrode continuously covering the entire area of ​​the electrode layer and the first insulating film and electrically connected to the surface of the contact electrode layer, wherein the portion of the transparent electrode that covers the entire area of ​​the electrode layer is only a flat portion that extends along the light-emitting surface.

[0124] This application claims priority based on Japanese Patent Application No. 2024-090812, filed on June 4, 2024, in the Japan Patent Office, the entire contents of which are incorporated herein by reference.

[0125] Those skilled in the art will recognize that various modifications, combinations, subcombinations, and variations may occur depending on design requirements and other factors, and are intended to be within the scope of the appended claims and their equivalents.

Claims

1. A light-emitting device comprising: a substrate; a light-emitting element provided on the substrate, the light-emitting element having an opposing surface facing the substrate, a light-emitting surface opposite the opposing surface, and an end surface connecting the opposing surface and the light-emitting surface; an electrode layer in contact with the entire area of ​​the light-emitting surface; a contact electrode layer provided in a second area of ​​the substrate different from a first area in which the light-emitting element is provided, the contact electrode layer including a surface located opposite the substrate; a first insulating film covering the end surface of the light-emitting element; and a transparent electrode continuously covering the entire area of ​​the electrode layer and the first insulating film and electrically connected to the surface of the contact electrode layer, wherein the only portion of the transparent electrode that covers the entire area of ​​the electrode layer is a flat portion that extends along the light-emitting surface.

2. The light emitting device according to claim 1, wherein the light emitting surface of the light emitting element is a flat surface.

3. The light emitting device according to claim 1, wherein the first insulating film includes a side surface that is continuous from the light emitting surface of the light emitting element to the surface of the contact electrode layer.

4. The light-emitting device according to claim 3, wherein the side surface of the first insulating film includes a flat portion extending along the end face of the light-emitting element and a curved portion connecting the flat portion to the light-emitting surface of the light-emitting element.

5. The light emitting device according to claim 1, wherein the contact electrode layer includes an opening along the outer edge of the light emitting element.

6. The light emitting device according to claim 5, wherein the junction region between the contact electrode layer and the transparent electrode is provided so as to surround at least a portion of the light emitting element in plan view.

7. The light emitting device according to claim 1, wherein the light emitting element includes a first conductivity type layer, an active layer, and a second conductivity type layer in this order from the substrate side.

8. The light-emitting device according to claim 7, wherein the first conductivity type layer is formed from an n-type GaN-based semiconductor material, and the second conductivity type layer is formed from a p-type GaN-based semiconductor material.

9. The light emitting device according to claim 1, further comprising a protective film between the end face of the light emitting element and the first insulating film.

10. The light emitting device according to claim 9, wherein the protective film is formed using at least one of aluminum oxide, titanium nitride, and resin.

11. The light emitting device according to claim 1, wherein the first insulating film is formed using at least one of SiO, SiN, and P-TEOS.

12. The light emitting device according to claim 1, further comprising a second insulating film between the first insulating film and the transparent electrode.

13. The light-emitting device according to claim 12, wherein the second insulating film has a multilayer structure having two or more types of layers.

14. The light emitting device according to claim 12, wherein the etching rate of the second insulating film is different from the etching rate of the first insulating film.

15. The second insulating film is made of SiO ２ 13. The light emitting device according to claim 12, wherein the light emitting device is formed using at least one of silicon nitride, silicon nitride, silicon oxynitride ...

16. The light-emitting device according to claim 1, further comprising: a heat dissipation section provided in a third region of the substrate different from a first region in which the light-emitting element is provided, the heat dissipation section having a thermal conductivity higher than that of the first insulating film; and a heat conduction path covering the end face of the light-emitting element via the first insulating film and connected to the heat dissipation section, the heat conduction path having a thermal conductivity higher than that of the first insulating film.

17. The light emitting device according to claim 16, wherein the heat dissipation portion includes a plurality of needle-like projections each extending in the thickness direction of the light emitting element.

18. The light emitting device according to claim 17, wherein the height of the needle-like projections along the thickness direction of the light emitting element is greater than the diameter of the needle-like projections.

19. The light emitting device according to claim 16, wherein the heat dissipation section is provided in the same layer as the light emitting element and contains the same material as the light emitting element.

20. The light-emitting device according to claim 16, wherein the heat conduction path is made of a metal containing at least one of Ag (silver), Cu (copper), Au (gold), Al (aluminum), Mg (magnesium), Zn (zinc), Fe (iron), W (tungsten), Sn (tin), Pb (lead), Ga (gallium), and Pt (platinum).

21. A light emitting device comprising: a substrate; one or more light emitting elements provided on the substrate, the light emitting elements having an opposing surface facing the substrate, a light emitting surface opposite the opposing surface, and an end surface connecting the opposing surface and the light emitting surface; a first insulating film covering the end surfaces of the one or more light emitting elements; a heat dissipation section provided in an area of ​​the substrate different from an area in which the one or more light emitting elements are respectively provided, the heat dissipation section having a thermal conductivity higher than that of the first insulating film; and a heat conduction path covering the end surfaces of the one or more light emitting elements via the first insulating film and connected to the heat dissipation section, the heat conduction path having a thermal conductivity higher than that of the first insulating film.

22. The light emitting device according to claim 21, wherein the one or more light emitting elements are a plurality of light emitting elements, and the heat dissipation portion is provided between the plurality of light emitting elements.

23. A method for manufacturing a light-emitting device, comprising: forming, on a substrate, a contact electrode layer and a light-emitting element having a light-emitting surface on the opposite side of the substrate; covering the contact electrode layer and the light-emitting element with an insulating film; selectively etching the insulating film to expose the entire area of ​​the light-emitting surface and at least a part of the contact electrode layer; and forming a transparent electrode that continuously covers the entire area of ​​the light-emitting surface of the light-emitting element and the insulating film and is electrically connected to the contact electrode layer.

24. The method for manufacturing a light-emitting device according to claim 23, further comprising providing an electrode layer so as to be in contact with the entire area of ​​the light-emitting surface, and forming the transparent electrode so as to cover the entire area of ​​the electrode layer.

25. The method for manufacturing a light-emitting device according to claim 23, further comprising selectively etching the insulating film so that the contact electrode layer is exposed in a ring shape in a plan view.

26. An image display device comprising a light-emitting device comprising: a substrate; a light-emitting element provided on the substrate and including an opposing surface facing the substrate, a light-emitting surface opposite the opposing surface, and an end surface connecting the opposing surface and the light-emitting surface; an electrode layer in contact with the entire area of ​​the light-emitting surface; a contact electrode layer provided in a second area of ​​the substrate different from a first area in which the light-emitting element is provided, and including a surface located opposite the substrate; a first insulating film covering the end surface of the light-emitting element; and a transparent electrode continuously covering the entire area of ​​the electrode layer and the first insulating film and electrically connected to the surface of the contact electrode layer, wherein the portion of the transparent electrode that covers the entire area of ​​the electrode layer is only a flat portion that extends along the light-emitting surface.

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