Light-emitting device and electronic apparatus

Abstract

To provide a light-emitting device capable of improving a light fetching-out efficiency.SOLUTION: A light-emitting device includes: a substrate; a first semiconductor layer of a first conductive type; a second semiconductor layer of a second conductive type that is different from the first conductive type; and a first lamination body including a first light emission layer that is provided between the first semiconductor layer and the second semiconductor layer; a first electrode that is provided between the substrate and the first lamination body, and is electrically connected to the first semiconductor layer; and a light transmissive second electrode that is provided to the side opposite to the substrate of the first lamination body, has a first opposite surface to the substrate, and is electrically connected to the second semiconductor layer; a first insulation layer that includes a first part provided to a side surface of the first lamination body and a second part that is provided to the first opposite surface and extended along the first opposite surface from the first part; and a first metal layer provided over the first part and the second part.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a light-emitting device and an electronic device. [Background technology]

[0002] Light emitting elements such as LEDs (Light Emitting Diodes) are used as light sources for display devices and the like.

[0003] For example, Patent Document 1 describes a micro LED element including a nitride semiconductor layer in which an N-type layer, a light-emitting layer, and a P-type layer are stacked in this order when viewed from the light-emitting surface side, a P-side electrode layer formed on the P-type layer, and an N-side electrode layer stacked on the light-emitting surface. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2019 / 038961 Summary of the Invention [Problem to be solved by the invention]

[0005] In the micro LED elements described above, it is desirable to improve the light extraction efficiency. [Means for solving the problem]

[0006] One aspect of the light emitting device according to the present invention is A substrate; a first laminate including a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type different from the first conductivity type, and a first light emitting layer provided between the first semiconductor layer and the second semiconductor layer; a first electrode provided between the substrate and the first stack and electrically connected to the first semiconductor layer; a second electrode having a first opposing surface facing the substrate, the second electrode being electrically connected to the second semiconductor layer; a first insulating layer having a first portion provided on a side surface of the first laminate and a second portion provided on the first opposing surface and extending from the first portion along the first opposing surface; a first metal layer disposed across the first portion and the second portion; Includes.

[0007] One aspect of the electronic device according to the present invention is The present invention has one aspect of the light emitting device. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a cross-sectional view illustrating a light emitting device according to an embodiment of the present invention. [Diagram 2] FIG. 1 is a cross-sectional view illustrating a light emitting device according to an embodiment of the present invention. [Diagram 3] 5A to 5C are cross-sectional views each showing a schematic process for manufacturing the light emitting device according to the embodiment. [Figure 4] 5A to 5C are cross-sectional views each showing a schematic process for manufacturing the light emitting device according to the embodiment. [Diagram 5] 5A to 5C are cross-sectional views each showing a schematic process for manufacturing the light emitting device according to the embodiment. [Figure 6] 5A to 5C are cross-sectional views each showing a schematic process for manufacturing the light emitting device according to the embodiment. [Figure 7] 5A to 5C are cross-sectional views each showing a schematic process for manufacturing the light emitting device according to the embodiment. [Figure 8] 5A to 5C are cross-sectional views each showing a schematic process for manufacturing the light emitting device according to the embodiment. [Figure 9] 5A to 5C are cross-sectional views each showing a schematic process for manufacturing the light emitting device according to the embodiment. [Figure 10] 5A to 5C are cross-sectional views each showing a schematic process for manufacturing the light emitting device according to the embodiment. [Figure 11] FIG. 1 is a diagram illustrating a projector according to an embodiment of the present invention. [Figure 12] FIG. 1 is a plan view illustrating a display according to an embodiment of the present invention. [Figure 13] FIG. 1 is a cross-sectional view illustrating a display according to an embodiment of the present invention. [Figure 14] FIG. 1 is a perspective view showing a schematic diagram of a head mounted display according to an embodiment of the present invention. [Figure 15] FIG. 2 is a diagram illustrating an image forming device and a light guiding device of the head mounted display according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Preferred embodiments of the present invention will be described in detail below with reference to the drawings. Note that the embodiments described below do not unduly limit the contents of the present invention described in the claims. In addition, not all of the configurations described below are necessarily essential components of the present invention.

[0010] 1. Light-emitting device Configuration First, the light emitting device according to the present embodiment will be described with reference to the drawings. Fig. 1 is a perspective view showing a schematic view of a light emitting device 100 according to the present embodiment.

[0011] 1, the light emitting device 100 includes, for example, a substrate 10, a laminate 20, a p-electrode 30, an n-electrode 32, an insulating layer 40, a lower metal layer 50, a protective layer 60, an upper metal layer 70, and a translucent member 80. The laminate 20, the p-electrode 30, the n-electrode 32, the insulating layer 40, and the lower metal layer 50 configure a light emitting element 2. The light emitting element 2 is, for example, an LED.

[0012] The substrate 10 is, for example, a silicon substrate. The substrate 10 is provided with a pad 12. The pad 12 has, for example, a first layer 14 and a second layer 16. The first layer 14 is provided on the substrate 10. The first layer 14 is, for example, a layer formed by laminating a Ti layer and a Pt layer in this order from the substrate 10 side. The second layer 16 is provided on the first layer 14. The second layer 16 is, for example, an Au layer.

[0013] The substrate 10 may be provided with a drive circuit for driving the light-emitting element 2. The light-emitting element 2 is mounted on the substrate 10 via pads 12. The light-emitting element 2 is, for example, junction-down mounted. For example, a plurality of light-emitting elements 2 are provided. When viewed from the stacking direction of the p-type semiconductor layer 22 and the light-emitting layer 24 of the laminate 20 (hereinafter also simply referred to as the "stacking direction"), the plurality of light-emitting elements 2 may be arranged in a matrix. In the illustrated example, a first light-emitting element 2a and a second light-emitting element 2b are provided as the light-emitting element 2. A plurality of pads 12 are provided corresponding to the plurality of light-emitting elements 2.

[0014] The laminate 20 is provided between the p-electrode 30 and the n-electrode 32. Here, FIG. 2 is an enlarged view of FIG. 1 showing the vicinity of the laminate 20. As shown in FIG. 2, the laminate 20 has a tapered portion 20a having a tapered shape in which the width increases from the p-electrode 30 side toward the n-electrode 32 side. The width of the tapered portion 20a gradually increases from the p-electrode 30 side toward the n-electrode 32 side. In the illustrated example, the shape of the tapered portion 20a is trapezoidal. Note that the width is the size in the direction perpendicular to the stacking direction. The side surface 21 of the tapered portion 20a is inclined with respect to the stacking direction. The side surface 21 of the tapered portion 20a constitutes the side surface of the laminate 20.

[0015] The laminate 20 includes a p-type semiconductor layer 22, a light emitting layer 24, and an n-type semiconductor layer 26. The p-type semiconductor layer 22, the light emitting layer 24, and the n-type semiconductor layer 26 form a tapered portion 20a. The p-type semiconductor layer 22, the light emitting layer 24, and the n-type semiconductor layer 26 are, for example, Group III nitride semiconductors and have a wurtzite crystal structure.

[0016] The p-type semiconductor layer 22 is provided on the p-electrode 30. The p-type semiconductor layer 22 is provided between the p-electrode 30 and the light emitting layer 24. The p-type semiconductor layer 22 has a first conductivity type. The p-type semiconductor layer 22 is, for example, a p-type GaN layer doped with Mg.

[0017] The light emitting layer 24 is provided on the p-type semiconductor layer 22. The light emitting layer 24 is provided between the p-type semiconductor layer 22 and the n-type semiconductor layer 26. The light emitting layer 24 has an i-type conductivity in which impurities are not intentionally doped. The light emitting layer 24 generates light when a current is injected into it. The light emitting layer 24 has, for example, a well layer and a barrier layer. The well layer and the barrier layer are i-type semiconductor layers. The well layer is, for example, an InGaN layer. The barrier layer is, for example, a GaN layer. The light emitting layer 24 has an MQW (Multiple Quantum Well) structure composed of a well layer and a barrier layer.

[0018] There is no particular limitation on the number of well layers and barrier layers constituting the light emitting layer 24. For example, only one well layer may be provided, in which case the light emitting layer 24 has a SQW (Single Quantum Well) structure.

[0019] The n-type semiconductor layer 26 is provided on the light emitting layer 24. The n-type semiconductor layer 26 is provided between the light emitting layer 24 and the n-electrode 32. In the illustrated example, the size of the n-type semiconductor layer 26 in the stacking direction is larger than the size of the p-type semiconductor layer 22 in the stacking direction. The n-type semiconductor layer 26 has a second conductivity type different from the first conductivity type. The n-type semiconductor layer 26 is, for example, an n-type GaN layer doped with Si.

[0020] The n-type semiconductor layer 26 has a contact surface 27 that contacts the n-electrode 32. The contact surface 27 is provided with a plurality of protrusions 28. The plurality of protrusions 28 are, for example, periodically provided. The height of the protrusions 28 is, for example, 400 nm or more. The distance between the tips of the adjacent protrusions 28 is, for example, 230 nm or less. The plurality of protrusions 28 may form a moth-eye structure. In the illustrated example, the laminate 20 is composed of a tapered portion 20a and a plurality of protrusions 28. The plurality of protrusions 28 can make the change in refractive index at the interface between the n-type semiconductor layer 26 and the n-electrode 32 gentle in the direction from the n-type semiconductor layer 26 toward the n-electrode 32. This can reduce light reflected at the interface between the n-type semiconductor layer 26 and the n-electrode 32. Although not illustrated, the plurality of protrusions 28 may be randomly provided.

[0021] In the light-emitting device 100, a pin diode is formed by the p-type semiconductor layer 22, the i-type light-emitting layer 24, and the n-type semiconductor layer 26. In the light-emitting device 100, when a forward bias voltage of the pin diode is applied between the p-electrode 30 and the n-electrode 32, a current is injected into the light-emitting layer 24, causing recombination of electrons and holes in the light-emitting layer 24. This recombination causes the light-emitting layer 24 to generate light.

[0022] The p-electrode 30 is provided between the substrate 10 and the p-type semiconductor layer 22. The p-electrode 30 is electrically connected to the p-type semiconductor layer 22. The p-type semiconductor layer 22 may be in ohmic contact with the p-electrode 30. The p-electrode 30 is, for example, formed by laminating a Pd layer, a Pt layer, and an Au layer in this order from the p-type semiconductor layer 22 side. The p-electrode 30 reflects light generated in the light-emitting layer 24 to the n-electrode 32 side.

[0023] The p-electrode 30 is one of the electrodes for injecting a current into the light-emitting layer 24. For example, a potential of a data signal is applied to the p-electrode 30. In the plurality of light-emitting elements 2, the p-electrode 30 is For example, they are spaced apart from each other.

[0024] The n-electrode 32 is provided on the side of the laminate 20 opposite to the substrate 10. The n-electrode 32 is provided on the n-type semiconductor layer 26. The n-electrode 32 is provided between the n-type semiconductor layer 26 and the light-transmitting member 80. The n-electrode 32 is disposed facing the substrate 10. The n-electrode 32 has a facing surface 34 facing the substrate 10. In the illustrated example, the facing surface 34 is the lower surface of the n-electrode 32. The n-electrode 32 is electrically connected to the n-type semiconductor layer 26. The n-type semiconductor layer 26 may be in ohmic contact with the n-electrode 32. The n-electrode 32 has light-transmitting properties. Specifically, the n-electrode 32 transmits light generated in the light-emitting layer 24. The light generated in the light-emitting layer 24 is emitted from the n-electrode 32 side. The material of the n-electrode 32 is, for example, ITO (Indium Tin Oxide).

[0025] The n-electrode 32 is the other electrode for injecting a current into the light-emitting layer 24. A constant potential, for example, is applied to the n-electrode 32. A ground potential may be applied to the n-electrode 32. In the multiple light-emitting elements 2, the n-electrode 32 is, for example, a common electrode. In the example shown in FIG. 1, the n-electrode 32 of the first light-emitting element 2a and the n-electrode 32 of the second light-emitting element 2b are provided continuously and integrally.

[0026] The insulating layer 40 is provided to cover the laminate 20. When viewed from the lamination direction, for example, the insulating layer 40 surrounds the laminate 20. The insulating layer 40 has light transmissivity. Specifically, the insulating layer 40 transmits light generated in the light emitting layer 24. The insulating layer 40 is, for example, a SiO2 layer. As shown in FIG. 2, the insulating layer 40 has, for example, a first extension portion 42, a second extension portion 44, and a third extension portion 46.

[0027] The first extension portion 42 of the insulating layer 40 is provided on the side surface 21 of the laminate 20. The first extension portion 42 extends along the side surface 21. The first extension portion 42 covers the entire surface of the side surface 21, for example.

[0028] The second extension portion 44 of the insulating layer 40 is provided on the opposing surface 34 of the n-electrode 32. In the illustrated example, the second extension portion 44 is provided on a portion of the opposing surface 34 that is parallel to the upper surface of the substrate 10. The second extension portion 44 is connected to the first extension portion 42. The second extension portion 44 extends from the first extension portion 42 along the opposing surface 34.

[0029] The third extension portion 46 of the insulating layer 40 is provided on the lower surface 31 of the p-electrode 30. The third extension portion 46 is connected to the first extension portion 42. The third extension portion 46 extends from the first extension portion 42 along the lower surface 31. A first contact hole 48 is formed in the third extension portion 46.

[0030] The lower metal layer 50 is provided across the first extension portion 42 and the second extension portion 44. In the illustrated example, the lower metal layer 50 is further provided across the third extension portion 46. The lower metal layer 50 is in contact with the extension portions 42, 44, and 46.

[0031] The lower metal layer 50 is further provided in the first contact hole 48. The lower metal layer 50 is connected to the p-electrode 30. The lower metal layer 50 is further connected to the pad 12. The lower metal layer 50 may be eutectic-bonded to the pad 12. The lower metal layer 50 may be Au-Au-bonded to the pad 12. The pad 12 is electrically connected to the p-electrode 30 via the lower metal layer 50. The lower metal layer 50 is, for example, an Au layer or an Al layer. The lower metal layer 50 reflects light generated in the light-emitting layer 24 toward the stack 20.

[0032] As shown in FIG. 1, the protective layer 60 is provided to cover the light-emitting element 2. When viewed from the stacking direction, the protective layer 60 surrounds the stacked body 20. The protective layer 60 is provided between the first light-emitting element 2a and the second light-emitting element 2b. The protective layer 60 is provided between the substrate 10 and the p-electrode 30. In the illustrated example, the protective layer 60 is separated from the substrate 10 via a gap. The protective layer 60 is, for example, a SiO2 layer. The protective layer 60 protects the light-emitting element 2 from foreign matter and the like, and prevents the n-electrode 32 from being disconnected by contacting the n-electrode 32 between the light-emitting elements 2.

[0033] 2, a second contact hole 62 is formed in the protective layer 60. In the illustrated example, the second contact hole 62 is provided with the second layer 16 of the pad 12.

[0034] As shown in FIG. 1, the upper metal layer 70 is provided on the side of the n-electrode 32 opposite the substrate 10. In the illustrated example, the upper metal layer 70 is provided on the n-electrode 32 via an adhesion layer 72. The adhesion layer 72 is, for example, a TiN layer. The adhesion layer 72 improves adhesion between the n-electrode 32 and the upper metal layer 70. When viewed from the stacking direction, for example, the upper metal layer 70 does not overlap with the stack 20. The upper metal layer 70 is, for example, an Al layer.

[0035] The upper metal layer 70 has a reflective surface 74. The reflective surface 74 is a side surface of the upper metal layer 70. In the illustrated example, the reflective surface 74 is located on an extension of the side surface 21 of the tapered portion 20a. The inclination of the reflective surface 74 with respect to the stacking direction is, for example, the same as the inclination of the side surface 21 with respect to the stacking direction. A plurality of reflective surfaces 74 are provided corresponding to the plurality of light-emitting elements 2. The reflective surface 74 reflects light generated in the light-emitting layer 24 toward the light-transmitting member 80.

[0036] The light-transmitting member 80 is provided on the side of the n-electrode 32 opposite to the substrate 10. The light-transmitting member 80 is provided on the n-electrode 32. The light-transmitting member 80 is in contact with the reflective surface 74 of the upper metal layer 70. When viewed from the stacking direction, for example, the upper metal layer 70 surrounds the light-transmitting member 80. The material of the light-transmitting member 80 is, for example, SiON. The light-transmitting member 80 transmits light that has passed through the n-electrode 32. The light-transmitting member 80 transmits light that has been reflected by the reflective surface 74.

[0037] The light-transmitting member 80 has an exit surface 82 that emits light generated in the light-emitting layer 24. The exit surface 82 is the surface of the light-transmitting member 80 opposite the substrate 10. The exit surface 82 is, for example, a curved surface. In the illustrated example, the exit surface 82 is a convex surface. A plurality of light-transmitting members 80 are provided corresponding to the plurality of light-emitting elements 2. In the illustrated example, adjacent light-transmitting members 80 are provided integrally and continuously with each other. The plurality of light-transmitting members 80 constitute, for example, a microlens array.

[0038] 1.2. Effects In the light emitting device 100, the first light emitting element 2a includes a laminate 20 as a first laminate having a p-type semiconductor layer 22 as a first semiconductor layer, an n-type semiconductor layer 26 as a second semiconductor layer, and a light emitting layer 24 as a first light emitting layer. Furthermore, the first light emitting element 2a includes a p-electrode 30 as a first electrode provided between the substrate 10 and the laminate 20 and electrically connected to the p-type semiconductor layer 22. Furthermore, the first light emitting element 2a includes an n-electrode 32 as a translucent second electrode provided on the opposite side of the laminate 20 from the substrate 10, having an opposing surface 34 as a first opposing surface facing the substrate 10, and electrically connected to the p-type semiconductor layer 22. Furthermore, the first light emitting element 2a includes an insulating layer 40 as a first insulating layer having a first extension portion 42 provided on the side surface 21 of the laminate 20 and a second extension portion 44 provided on the opposing surface 34 and extending from the first extension portion 42 along the opposing surface 34. Furthermore, the first light-emitting element 2a includes a lower metal layer 50 provided across the first extension portion 42 and the second extension portion 44 as a first metal layer.

[0039] Therefore, in the light emitting device 100, the lower metal layer 50 can reflect the light generated in the light emitting layer 24 more toward the stack 20 than in a case where the lower metal layer is not provided across the first and second extension parts of the insulating layer, but is provided only on a part of the first extension part. This can improve the light extraction efficiency.

[0040] In the light emitting device 100, the lower metal layer 50 is connected to the p-electrode 30. Therefore, the light emitting device 100 can be made smaller than when, for example, the lower metal layer is separated from the p-electrode. When the lower metal layer and the p-electrode are separated, the misalignment between them must be taken into consideration at the time of design, making it difficult to make the device smaller.

[0041] In the light emitting device 100, the second light emitting element 2b includes a laminate 20 as a second laminate having a p-type semiconductor layer 22 as a third semiconductor layer, an n-type semiconductor layer 26 as a fourth semiconductor layer, and a light emitting layer 24 as a second light emitting layer. Furthermore, the second light emitting element 2b includes a p-electrode 30 as a third electrode provided between the substrate 10 and the laminate 20 and electrically connected to the p-type semiconductor layer 22. Furthermore, the second light emitting element 2b includes an n-electrode 32 as a translucent fourth electrode provided on the opposite side of the laminate 20 from the substrate 10, having an opposing surface 34 as a second opposing surface facing the substrate 10, and electrically connected to the p-type semiconductor layer 22. Furthermore, the second light emitting element 2b includes an insulating layer 40 as a second insulating layer having a first extension portion 42 as a third portion provided on the side surface 21 of the laminate 20 and a second extension portion 44 as a fourth portion provided on the opposing surface 34 and extending from the first extension portion 42 along the opposing surface 34. Furthermore, the second light-emitting element 2b includes a lower metal layer 50 as a second metal layer provided across the first extension portion 42 and the second extension portion 44. Therefore, in the light-emitting device 100, the lower metal layer 50 can reduce crosstalk between the first light-emitting element 2a and the second light-emitting element 2b.

[0042] In the light emitting device 100, the p-electrode 30 of the first light emitting element 2a and the p-electrode 30 of the second light emitting element 2b are provided continuously and integrally. Therefore, in the light emitting device 100, the p-electrode 30 can be used as a common electrode in the first light emitting element 2a and the second light emitting element 2b.

[0043] In the light emitting device 100, the laminate 20 has a tapered portion 20a whose width increases from the p-electrode 30 side toward the n-electrode 32 side. Therefore, in the light emitting device 100, the side surface 21 can reflect light generated in the light emitting layer 24 toward the n-electrode 32 side.

[0044] Light emitting device 100 includes upper metal layer 70 as a third metal layer provided on the side opposite substrate 10 of n-electrode 32 and having reflective surface 74 for reflecting light generated in light emitting layer 24, and reflective surface 74 is located on an extension of side surface 21 of tapered portion 20a. Therefore, light emitting device 100 can emit light with a narrower radiation angle while suppressing leakage of light transmitted through n-electrode 32 to the outside.

[0045] The light emitting device 100 includes a light-transmitting member 80 that is provided on the side of the n-electrode 32 opposite the substrate 10 and in contact with the reflective surface 74. Therefore, in the light emitting device 100, the light that has passed through the light-transmitting member 80 and is incident on the reflective surface 74 can be more reliably reflected toward the light-transmitting member 80 at the reflective surface 74.

[0046] In the light emitting device 100, the light emitting surface 82 of the light-transmitting member 80 opposite to the substrate 10 is a curved surface. Therefore, in the light emitting device 100, the light-transmitting member 80 can function as a lens.

[0047] In the light emitting device 100, the insulating layer 40 is light transmissive. In the light emitting device 100, even if the light generated in the light emitting layer 24 passes through the light transmissive insulating layer 40, the lower metal layer 50 can reflect the light that has passed through the insulating layer 40 toward the stack 20.

[0048] In the above, the semiconductor layer provided between the substrate 10 and the light emitting layer 24 is a p-type semiconductor layer, and the semiconductor layer provided on the side of the light emitting layer 24 opposite to the substrate 10 is an n-type semiconductor layer, but the p-type and n-type may be reversed. That is, the semiconductor layer provided between the substrate 10 and the light emitting layer 24 may be an n-type semiconductor layer, and the semiconductor layer provided on the side of the light emitting layer 24 opposite to the substrate 10 may be a p-type semiconductor layer. In this case, the electrode electrically connected to the semiconductor layer provided between the substrate 10 and the light emitting layer 24 becomes an n-electrode, and the electrode electrically connected to the semiconductor layer provided on the side of the light emitting layer 24 opposite to the substrate 10 becomes a p-electrode.

[0049] Although an example in which there is a gap between the substrate 10 and the protective layer 60 has been described above, the substrate 10 and the protective layer 60 may be in contact with each other. In this case, the pad 12 may be embedded in the substrate 10. The pad 12 and the light-emitting element 2 may be connected to each other by hybrid bonding.

[0050] In addition, in the above, an example has been described in which the lower metal layer 50 is provided in the first contact hole 48, but as long as the pad 12 is electrically connected to the p-electrode 30, the first contact hole 48 may be provided with the pad 12 instead of the lower metal layer 50.

[0051] Although the above describes the InGaN-based light emitting layer 24, various material systems capable of emitting light when a current is injected therein can be used for the light emitting layer 24 depending on the wavelength of the emitted light. For example, semiconductor materials such as AlGaN-based, AlGaAs-based, InGaAs-based, InGaAsP-based, InP-based, GaP-based, and AlGaP-based materials can be used.

[0052] 2. Manufacturing method of light-emitting device Next, a method for manufacturing the light emitting device 100 according to this embodiment will be described with reference to the drawings. Figures 3 to 10 are cross-sectional views that typically show the manufacturing process for the light emitting device 100 according to this embodiment.

[0053] As shown in FIG. 3, an n-type semiconductor layer 26, a light emitting layer 24, and a p-type semiconductor layer 22 are epitaxially grown in this order on a growth substrate 17. Examples of the epitaxial growth method include a metal organic chemical vapor deposition (MOCVD) method and a molecular beam epitaxy (MBE) method. A stacked body 20 is formed by this process. The growth substrate 17 is a substrate for epitaxially growing the stacked body 20. The growth substrate 17 has, for example, a support substrate 18 and a buffer layer 19 provided on the support substrate 18. The support substrate 18 is, for example, a silicon substrate. The buffer layer 19 is, for example, a GaN layer.

[0054] Next, the p-electrode 30 is formed on the stack 20. The p-electrode 30 is formed by, for example, a vacuum deposition method, a sputtering method, or a CVD (Chemical Vapor Deposition) method.

[0055] Next, the p-electrode 30 and the laminate 20 are patterned. The patterning is performed so that the side surface 21 of the tapered portion 20a of the laminate 20 is inclined with respect to the lamination direction. The patterning is performed by, for example, photolithography and dry etching. By patterning the p-electrode 30 and the laminate 20 at the same time, the manufacturing process of the light emitting device 100 can be shortened.

[0056] Next, the insulating layer 40 is formed on the stack 20 and the buffer layer 19. The insulating layer 40 is formed by, for example, a CVD method or an ALD method.

[0057] Next, the insulating layer 40 is patterned to form a first contact hole 48. This exposes the p-electrode 30. The patterning is performed by, for example, photolithography and etching.

[0058] 4, the lower metal layer 50 is formed on the p-electrode 30 and the insulating layer 40. The lower metal layer 50 is formed by, for example, a vacuum deposition method or a sputtering method.

[0059] 5, a resist layer 90 having a predetermined shape is formed so as to cover the laminate 20. The resist layer 90 is formed by coating, exposing, and developing.

[0060] 6, the lower metal layer 50 and the insulating layer 40 are dry etched using the resist layer 90 as a mask, thereby exposing the buffer layer 19. Here, it is not necessary to completely dry etch the insulating layer 40 to expose the buffer layer 19.

[0061] 7, the resist layer 90 is removed. The method for removing the resist layer 90 is not particularly limited.

[0062] 8, a protective layer 60 is formed so as to cover the laminate 20. The protective layer 60 is formed by, for example, a CVD method or a spin coating method, and the protective layer 60 is planarized using a CMP (Chemical Mechanical Polishing) device or the like.

[0063] Next, the protective layer 60 is patterned to form a second contact hole 62. This exposes the lower metal layer 50. The patterning is performed by, for example, photolithography and etching.

[0064] 9, the lower metal layer 50 is bonded to the pad 12. Examples of the bonding include eutectic bonding, Au-Au bonding, etc. The two may also be bonded using solder or the like.

[0065] 10, the growth substrate 17 is removed. The growth substrate 17 is removed by, for example, etching, CMP, etc. As a result, the n-type semiconductor layer 26 is exposed.

[0066] Next, the n-type semiconductor layer 26 is patterned to form a plurality of protrusions 28. The patterning is performed by, for example, photolithography and etching.

[0067] 1, an n-electrode 32 is formed on the n-type semiconductor layer 26. The n-electrode 32 is formed by, for example, a vacuum deposition method or a sputtering method.

[0068] Next, an upper metal layer 70 is formed on the n-electrode 32 via an adhesion layer 72. The upper metal layer 70 and the adhesion layer 72 are formed by, for example, a sputtering method, a CVD method, a vacuum deposition method, or a plating method.

[0069] Next, the light-transmitting member 80 is formed on the n-electrode 32. The light-transmitting member 80 is formed by, for example, a CVD method.

[0070] Next, the light-transmitting member 80 is patterned to form the curved emission surface 82. The patterning is performed by, for example, photolithography and etching.

[0071] Through the above steps, the light emitting device 100 can be manufactured.

[0072] 3. Projector Next, a projector as an electronic device according to this embodiment will be described with reference to the drawings. Fig. 11 is a diagram showing a schematic diagram of a projector 700 according to this embodiment.

[0073] The projector 700 includes, for example, a light emitting device 100 as a light source.

[0074] Projector 700 has a housing (not shown), and red light source 100R, green light source 100G, and blue light source 100B that are provided in the housing and emit red light, green light, and blue light, respectively. For convenience, red light source 100R, green light source 100G, and blue light source 100B are illustrated in a simplified form in FIG.

[0075] The projector 700 further includes, for example, a first optical element 702R, a second optical element 702G, a third optical element 702B, a first light modulation device 704R, a second light modulation device 704G, a third light modulation device 704B, and a projection device 708, which are provided in the housing. The first light modulation device 704R, the second light modulation device 704G, and the third light modulation device 704B are, for example, transmissive liquid crystal light valves. The projection device 708 is, for example, a projection lens.

[0076] The light emitted from red light source 100R is incident on first optical element 702R. The light emitted from red light source 100R is collected by first optical element 702R. Note that first optical element 702R may have a function other than collecting light. Second optical element 702G and third optical element 702B may also have a function other than collecting light.

[0077] The light collected by the first optical element 702R is incident on the first light modulation device 704R. The first light modulation device 704R modulates the incident light in accordance with image information. The projection device 708 then enlarges the image formed by the first light modulation device 704R and projects it onto the screen 710.

[0078] The light emitted from green light source 100G is incident on second optical element 702G. The light emitted from green light source 100G is collected by second optical element 702G.

[0079] The light collected by the second optical element 702G is incident on the second light modulation device 704G. The second light modulation device 704G modulates the incident light in accordance with image information. The projection device 708 then enlarges the image formed by the second light modulation device 704G and projects it onto the screen 710.

[0080] The light emitted from blue light source 100B is incident on third optical element 702B. The light emitted from blue light source 100B is collected by third optical element 702B.

[0081] The light collected by the third optical element 702B enters the third light modulation device 704B. The third light modulation device 704B modulates the incident light in accordance with image information. The projection device 708 then enlarges the image formed by the third light modulation device 704B and projects it onto the screen 710.

[0082] The projector 700 further includes a cross dichroic prism 706 that combines the light emitted from the first light modulation device 704R, the second light modulation device 704G, and the third light modulation device 704B, and guides the combined light to a projection device 708.

[0083] The three color lights modulated by the first light modulation device 704R, the second light modulation device 704G, and the third light modulation device 704B are incident on a cross dichroic prism 706. The dichroic prism 706 is formed by bonding four right-angle prisms together, and a dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light are disposed on its inner surface. These dielectric multilayer films combine the three color lights to form light that represents a color image. The combined light is then projected by the projection device 708 onto the screen 710, and an enlarged image is displayed.

[0084] Note that red light source 100R, green light source 100G, and blue light source 100B may directly form an image without using first light modulation device 704R, second light modulation device 704G, and third light modulation device 704B, by controlling light emitting device 100 as a pixel of the image according to image information. Then, projection device 708 may enlarge and project the image formed by red light source 100R, green light source 100G, and blue light source 100B onto screen 710.

[0085] In the above example, a transmissive liquid crystal light valve is used as the light modulation device, but a light valve other than liquid crystal may be used, or a reflective light valve may be used. Examples of such light valves include a reflective liquid crystal light valve and a digital micro mirror device. The configuration of the projection device is appropriately changed depending on the type of light valve used.

[0086] The light source can also be applied to a light source device of a scanning type image display device having a scanning means, which is an image forming device that displays an image of a desired size on a display surface by scanning light from the light source on a screen.

[0087] 4. Display Next, a display as an electronic device according to this embodiment will be described with reference to the drawings. Fig. 12 is a plan view showing a display 800 according to this embodiment. Fig. 13 is a cross-sectional view showing a display 800 according to this embodiment. Note that Fig. 12 shows an X-axis and a Y-axis as two mutually orthogonal axes. For convenience, Figs. 12 and 13 show a simplified light-emitting device 100.

[0088] The display 800 includes, for example, a light emitting device 100 as a light source.

[0089] The display 800 is a display device that displays an image. The image includes an image that displays only text information. The display 800 is a self-luminous display. As shown in Figs. 12 and 13, the display 800 has, for example, a driving circuit 810, a lens array 820, and a heat sink 830.

[0090] The driving circuit 810 is provided on the substrate 10. The driving circuit 810 drives the light-emitting element 2 based on, for example, input image information. The substrate 10 has, for example, a display area 812. The driving circuit 810 has a data line driving circuit 814, a scanning line driving circuit 816, and a control circuit 818.

[0091] The display area 812 is made up of a plurality of pixels P. In the illustrated example, the pixels P are arranged along the X-axis and the Y-axis.

[0092] Although not shown, a plurality of scanning lines and a plurality of data lines are provided on the substrate 10. For example, the scanning lines extend along the X-axis, and the data lines extend along the Y-axis. The scanning lines are connected to a scanning line driving circuit 816. The data lines are connected to a data line driving circuit 814. Pixels P are provided at intersections of the scanning lines and the data lines.

[0093] One pixel P has, for example, one light-emitting element 2, one light-transmitting member 80, and a pixel circuit (not shown). The pixel circuit has a switching transistor that functions as a switch for the pixel P. The gate of the switching transistor is connected to a scanning line, and one of the source and drain is connected to a data line.

[0094] The data line driving circuit 814 and the scanning line driving circuit 816 are circuits that control the driving of the light emitting elements 2 that constitute the pixels P. The control circuit 818 controls the display of images.

[0095] Image data is supplied from a higher-level circuit to the control circuit 818. The control circuit 818 supplies various signals based on the image data to the data line driving circuit 814 and the scanning line driving circuit 816.

[0096] When the scanning line driving circuit 816 activates a scanning signal to select a scanning line, the switching transistor of the selected pixel P is turned on. At this time, the data line driving circuit 814 supplies a data signal from the data line to the selected pixel P, causing the light emitting element 2 of the selected pixel P to emit light in response to the data signal.

[0097] The lens array 820 is composed of a plurality of light-transmitting members 80. The heat sink 830 is in contact with the substrate 10. The material of the heat sink 830 is, for example, a metal such as copper or aluminum. The heat sink 830 dissipates heat generated by the light-emitting element 2.

[0098] 5. Head-mounted displays 5.1. Overall structure Next, a head mounted display as an electronic device according to this embodiment will be described with reference to the drawings. Fig. 14 is a perspective view showing a schematic diagram of a head mounted display 900 according to this embodiment.

[0099] The head mounted display 900 is a head-mounted display having an appearance like glasses, as shown in Fig. 14. The head mounted display 900 is worn on the head of an observer. The observer is a user who uses the head mounted display 900. The head mounted display 900 allows the observer to view image light formed by a virtual image, and also allows the observer to view an external world image in a see-through manner.

[0100] The head mounted display 900 has, for example, a first display unit 910a, a second display unit 910b, a frame 920, a first temple 930a, and a second temple 930b.

[0101] The first display unit 910a and the second display unit 910b display images. Specifically, the first display unit 910a displays a virtual image for the observer's right eye. The second display unit 910b displays a virtual image for the observer's left eye. The display units 910a and 910b each include, for example, an image forming device 911 and a light guide device 915.

[0102] The image forming device 911 forms image light. The image forming device 911 has an optical system, such as a light source and a projection device, and an external member 912. The external member 912 houses the light source and the projection device.

[0103] The light guiding device 915 covers the viewer's eyes. The light guiding device 915 guides the image light formed by the image forming device 911 and allows the viewer to visually recognize the image light overlapping with the outside light. Details of the image forming device 911 and the light guiding device 915 will be described later.

[0104] The frame 920 supports the first display unit 910a and the second display unit 910b. The frame 920, for example, surrounds the display units 910a and 910b. In the illustrated example, the image forming device 911 of the first display unit 910a is attached to one end of the frame 920. The image forming device 911 of the second display unit 910b is attached to the other end of the frame 920.

[0105] A first temple 930a and a second temple 930b extend from the frame 920. In the illustrated example, the first temple 930a extends from one end of the frame 920. The second temple 930b extends from the other end of the frame 920.

[0106] The first temple 930a and the second temple 930b are suspended from the ears of the viewer when the viewer wears the head mounted display 900. The viewer's head is positioned between the temples 930a and 930b.

[0107] 5.2. Image forming and light directing devices 15 is a diagram illustrating an image forming device 911 and a light guide device 915 of a first display unit 910a of a head mounted display 900. The first display unit 910a and the second display unit 910b basically have the same configuration. Therefore, the following description of the first display unit 910a can be applied to the second display unit 910b.

[0108] As shown in FIG. 15, the image forming device 911 includes, for example, a light emitting device 100 as a light source, a light modulation device 913, and a projection device 914 for forming an image.

[0109] The light modulation device 913 modulates the light incident from the light emitting device 100 in accordance with image information, and emits image light. The light modulation device 913 is a transmissive liquid crystal light valve. The light emitting device 100 may be a self-luminous light emitting device that emits light in accordance with input image information. In this case, the light modulation device 913 is not provided.

[0110] The projection device 914 projects the image light emitted from the light modulation device 913 toward the light guide device 915. The projection device 914 is, for example, a projection lens. As a lens constituting the projection device 914, a lens having an axially symmetric surface as a lens surface may be used.

[0111] The light guiding device 915 is precisely positioned with respect to the projection device 914 by, for example, being screwed to the lens barrel of the projection device 914. The light guiding device 915 has, for example, an image light guiding member 916 that guides the image light, and a see-through member 918 for see-through.

[0112] The image light emitted from the projection device 914 is incident on the image light guiding member 916. The image light guiding member 916 is a prism that guides the image light toward the viewer's eye. The image light that enters the image light guiding member 916 is repeatedly reflected on the inner surface of the image light guiding member 916, and is then reflected by the reflective layer 917 and emitted from the image light guiding member 916. The image light that is emitted from the image light guiding member 916 reaches the viewer's eye. The reflective layer 917 is made of, for example, a metal or a dielectric multilayer film. The reflective layer 917 may be a half mirror.

[0113] The transparent member 918 is adjacent to the image light guiding member 916. The transparent member 918 is fixed to the image light guiding member 916. For example, the outer surface of the transparent member 918 is continuous with the outer surface of the image light guiding member 916. The transparent member 918 allows the observer to see outside light through it. The image light guiding member 916 also has a function of allowing the observer to see outside light through it, in addition to the function of guiding the image light. Note that the head mounted display 900 may be configured not to allow the observer to see outside light through it.

[0114] The light emitting device according to the above-described embodiment can be used for applications other than projectors, displays, and head-mounted displays. The light emitting device according to the above-described embodiment can be used for, for example, indoor and outdoor lighting, laser printers, scanners, sensing devices using light, EVFs (Electronic View Finders), wearable displays such as smart watches, in-vehicle lights, and in-vehicle head-up displays.

[0115] The above-described embodiment and modifications are merely examples, and the present invention is not limited to these. For example, the embodiments and modifications can be appropriately combined.

[0116] The present invention includes configurations that are substantially the same as the configurations described in the embodiments, for example, configurations with the same functions, methods, and results, or configurations with the same purpose and effect. The present invention also includes configurations in which non-essential parts of the configurations described in the embodiments are replaced. The present invention also includes configurations that achieve the same effects as the configurations described in the embodiments, or configurations that can achieve the same purpose. The present invention also includes configurations in which publicly known technology is added to the configurations described in the embodiments.

[0117] The following can be derived from the above-described embodiment and modifications.

[0118] One aspect of the light emitting device is A substrate; a first laminate including a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type different from the first conductivity type, and a first light emitting layer provided between the first semiconductor layer and the second semiconductor layer; a first electrode provided between the substrate and the first stack and electrically connected to the first semiconductor layer; a second electrode having a first opposing surface facing the substrate, the second electrode being electrically connected to the second semiconductor layer; a first insulating layer having a first portion provided on a side surface of the first laminate and a second portion provided on the first opposing surface and extending from the first portion along the first opposing surface; a first metal layer disposed across the first portion and the second portion; Includes.

[0119] According to this light emitting device, the light extraction efficiency can be improved.

[0120] In one embodiment of the light emitting device, The first metal layer may be connected to the first electrode.

[0121] This light emitting device can be made smaller.

[0122] In one embodiment of the light emitting device, a second stacked body including a third semiconductor layer of the first conductivity type, a fourth semiconductor layer of the second conductivity type, and a second light emitting layer provided between the third semiconductor layer and the fourth semiconductor layer; a third electrode provided between the substrate and the second stack and electrically connected to the third semiconductor layer; a fourth electrode having a second opposing surface facing the substrate, the fourth electrode being electrically connected to the fourth semiconductor layer; a second insulating layer having a third portion provided on a side surface of the second laminate and a fourth portion provided on the second opposing surface and extending from the third portion along the second opposing surface; a second metal layer disposed across the third portion and the fourth portion; may include:

[0123] This light-emitting device can reduce crosstalk between a first light-emitting element including a first stack, a first electrode, and a second electrode, and a second light-emitting element including a second stack, a third electrode, and a fourth electrode.

[0124] In one embodiment of the light emitting device, The second electrode and the fourth electrode may be provided integrally and continuously.

[0125] According to this light emitting device, the second electrode and the fourth electrode can be used as a common electrode in the first light emitting element and the second light emitting element.

[0126] In one embodiment of the light emitting device, The first laminate may have a tapered portion whose width increases from the first electrode side toward the second electrode side.

[0127] According to this light emitting device, the light generated in the first light emitting layer can be reflected at the side surface of the laminate towards the second electrode side.

[0128] In one embodiment of the light emitting device, a third metal layer provided on the second electrode opposite to the substrate and having a reflective surface that reflects light generated in the first light emitting layer; The reflecting surface may be located on an extension of a side surface of the tapered portion.

[0129] According to this light emitting device, it is possible to suppress leakage of light transmitted through the second electrode to the outside, and to emit light with a narrower emission angle.

[0130] In one embodiment of the light emitting device, The light-transmitting element may include a light-transmitting member provided on the second electrode opposite to the substrate and in contact with the reflective surface.

[0131] According to this light emitting device, the light that has passed through the light-transmitting member and is incident on the reflecting surface can be more reliably reflected toward the light-transmitting member at the reflecting surface.

[0132] In one embodiment of the light emitting device, The surface of the light-transmitting member opposite to the substrate may be a curved surface.

[0133] According to this light emitting device, the light transmitting member can function as a lens.

[0134] In one embodiment of the light emitting device, The first insulating layer may be light-transmitting.

[0135] According to this light-emitting device, even if the light generated in the first light-emitting layer passes through the light-transmitting first insulating layer, the first metal layer can reflect the light that has passed through the first insulating layer toward the first laminate side.

[0136] One aspect of the electronic device is The present invention has one aspect of the light emitting device. [Explanation of symbols]

[0137] 2...light-emitting element, 2a...first light-emitting element, 2b...second light-emitting element, 10...substrate, 12...pad, 14...First layer, 16...Second layer, 17...Growth substrate, 18...Support substrate, 19...Buffer layer, 20...Laminated body, 20a...Tapered part, 21...Side surface, 22...P-type semiconductor layer, 24...Light emitting layer, 2 6...n-type semiconductor layer, 27...contact surface, 28...convex part, 30...p electrode, 31...bottom surface, 32...n electrode, 34...opposed surface, 40...insulating layer, 42...first extension part, 44...second extension part, 46...third extension part , 48...first contact hole, 50...lower metal layer, 60...protective layer, 62...second contact hole, 70...upper metal layer, 72...adhesion layer, 74...reflective surface, 80...light-transmitting member, 82...emission surface, 90...resist layer, 100...light-emitting device, 100R...red light source, 100G...green light source, 100B...blue light source, 700...projector, 702R...first optical element, 702G...second optical element 702B...third optical element, 704R...first optical modulation device, 704G...second optical modulation device, 704B...third optical modulation device, 706...cross dichroic prism, 708...projection device, 710...screen, 800...display, 810...drive circuit, 812...display area, 814...data line drive circuit, 816...scanning line drive circuit, 818...control circuit, 820...lens Array, 830...heat sink, 900...head mounted display, 910a...first display section, 910b...second display section, 911...image forming device, 912...external member, 913...light modulation device, 914...projection device, 915...light guide device, 916...image light guide member, 917...reflective layer, 918...transparent member, 920...frame, 930a...first temple, 930b...second temple

Claims

1. A substrate; a first stacked body including a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type different from the first conductivity type, and a first light emitting layer provided between the first semiconductor layer and the second semiconductor layer; a first electrode provided between the substrate and the first stack and electrically connected to the first semiconductor layer; a second electrode having a first opposing surface facing the substrate and electrically connected to the second semiconductor layer; a first insulating layer having a first portion provided on a side surface of the first stack and a second portion provided on the first opposing surface and extending from the first portion along the first opposing surface; a first metal layer disposed across the first portion and the second portion; A light emitting device comprising:

2. In claim 1, The first metal layer is connected to the first electrode.

3. In claim 1, a second stacked body including a third semiconductor layer of the first conductivity type, a fourth semiconductor layer of the second conductivity type, and a second light emitting layer provided between the third semiconductor layer and the fourth semiconductor layer; a third electrode provided between the substrate and the second stack and electrically connected to the third semiconductor layer; a fourth electrode having a second opposing surface facing the substrate and electrically connected to the fourth semiconductor layer, the fourth electrode being provided on the opposite side of the second stack from the substrate; a second insulating layer having a third portion provided on a side surface of the second stack and a fourth portion provided on the second opposing surface and extending from the third portion along the second opposing surface; a second metal layer disposed across the third portion and the fourth portion; A light emitting device comprising:

4. In claim 3, The second electrode and the fourth electrode are provided integrally and continuously.

5. In claim 1, The first laminate has a tapered portion whose width increases from the first electrode side toward the second electrode side.

6. In claim 5, a third metal layer provided on the second electrode opposite to the substrate and having a reflective surface that reflects light generated in the first light emitting layer; A light emitting device, wherein the reflective surface is located on an extension of a side surface of the tapered portion.

7. In claim 6, a light-transmitting member provided on the opposite side of the second electrode from the substrate and in contact with the reflective surface;

8. In claim 7, A light emitting device, wherein the surface of the light transmissive member opposite to the substrate is curved.

9. In claim 1, The first insulating layer is light-transmitting.

10. 10. An electronic device comprising the light emitting device according to claim 1.

Images