Light emitting element

Abstract

To provide a light emitting element capable of improving light extraction efficiency.SOLUTION: A light emitting element 100 includes: a conductive member 10 having a first through hole 10h; a reflective layer 20 disposed inside the first through hole 10h; an insulating layer 30 disposed on the conductive member 10 and the reflective layer 20 and having a second through hole 30h disposed at a position not overlapping with the first through hole 10h in a plan view; a semiconductor structure 40 disposed on the insulating layer 30 and having a p-type semiconductor layer 41, a light emitting layer 42, and an n-type semiconductor layer 43; an n-electrode 50 disposed on the n-type semiconductor layer 43; and a p-electrode 60 electrically connected to the conductive member 10. The reflectance of the reflective layer 20 at the peak wavelength of the light emitted by the light emitting layer 42 is higher than the reflectance of the conductive member 10 at the peak wavelength of the light emitted by the light emitting layer 42. A portion of the conductive member 10 is in contact with the p-type semiconductor layer 41 at the second through hole 30h. At least a part of the reflective layer 20 overlaps with the light emitting layer 42 in a plan view.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The embodiment relates to a light emitting device. [Background technology]

[0002] In a light-emitting device, a structure is known in which a conductive member is provided below a semiconductor structure including a light-emitting layer, and light emitted from the light-emitting layer is reflected upward by the conductive member (for example, Patent Document 1). However, in such a structure, a part of the light emitted from the light-emitting layer may be absorbed by the conductive member, resulting in a decrease in light extraction efficiency. There is a demand for an improvement in the light extraction efficiency of light-emitting devices. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-138007 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the embodiment is to provide a light emitting element capable of improving light extraction efficiency. [Means for solving the problem]

[0005] A light-emitting element according to an embodiment of the present invention includes a conductive member, a reflective layer, an insulating layer, a semiconductor structure, an n-electrode, and a p-electrode. The conductive member has a first through hole. The reflective layer is disposed inside the first through hole. The insulating layer is disposed on the conductive member and the reflective layer. The insulating layer has a second through hole. The second through hole is disposed at a position that does not overlap with the first through hole in a plan view. The semiconductor structure includes a p-type semiconductor layer, a light-emitting layer, and an n-type semiconductor layer. The p-type semiconductor layer is disposed on the insulating layer. The light-emitting layer is disposed on the p-type semiconductor layer. The n-type semiconductor layer is partially disposed on the light-emitting layer. The n-electrode is disposed on the n-type semiconductor layer. The n-electrode is connected to the n-type semiconductor layer. The p-electrode is connected to the conductive member. The reflectance of the reflective layer at the peak wavelength of the light emitted by the light-emitting layer is higher than the reflectance of the conductive member at the peak wavelength of the light emitted by the light-emitting layer. A portion of the conductive member contacts the p-type semiconductor layer at the second through hole. In a plan view, at least a portion of the reflective layer is disposed at a position overlapping the light emitting layer. Effect of the Invention

[0006] According to one embodiment of the present invention, a light emitting device capable of improving light extraction efficiency can be realized. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a plan view illustrating a light emitting device according to an embodiment. [Diagram 2] FIG. 2 is a plan view illustrating the arrangement of a conductive member and a reflective layer of the light-emitting element according to the embodiment. [Diagram 3] 1 is a cross-sectional view illustrating a schematic configuration of a light-emitting device according to an embodiment. [Figure 4] 2 is an enlarged cross-sectional view illustrating a part of the light-emitting device according to the embodiment. FIG. [Diagram 5] FIG. 11 is a plan view illustrating an arrangement of a conductive member and a reflective layer of a light-emitting element according to a first modified example of the embodiment. [Figure 6]FIG. 4 is a cross-sectional view diagrammatically illustrating a light-emitting device according to a first modified example of the embodiment. [Figure 7] FIG. 11 is a plan view illustrating an arrangement of a conductive member and a reflective layer of a light-emitting element according to a second modified example of the embodiment. [Figure 8] FIG. 13 is a plan view illustrating an arrangement of a conductive member and a reflective layer of a light-emitting element according to a third modified example of the embodiment. [Figure 9] FIG. 13 is a plan view illustrating the arrangement of a conductive member and a reflective layer of a light-emitting element according to a fourth modified example of the embodiment. [Figure 10] FIG. 13 is a plan view illustrating an arrangement of a conductive member and a reflective layer of a light-emitting element according to a fifth modified example of the embodiment. [Figure 11] FIG. 13 is a cross-sectional view illustrating a schematic configuration of a light-emitting device according to a fifth modified example of the embodiment. [Figure 12] 1A to 1C are cross-sectional views illustrating a method for manufacturing a light-emitting element according to an embodiment. [Figure 13] 1A to 1C are cross-sectional views illustrating a method for manufacturing a light-emitting element according to an embodiment. [Figure 14] 1A to 1C are cross-sectional views illustrating a method for manufacturing a light-emitting element according to an embodiment. [Figure 15] 1A to 1C are cross-sectional views illustrating a method for manufacturing a light-emitting element according to an embodiment. [Figure 16] 1A to 1C are cross-sectional views illustrating a method for manufacturing a light-emitting element according to an embodiment. [Figure 17] 1A to 1C are cross-sectional views illustrating a method for manufacturing a light-emitting element according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the size ratio between parts, etc. are not necessarily the same as those in reality. Even when the same part is shown, the dimensions and ratios of each part may be different depending on the drawing. In this specification and each drawing, elements similar to those already explained are given the same reference numerals and detailed explanations are omitted as appropriate.

[0009] For ease of explanation, the following describes the arrangement and configuration of each part using an XYZ Cartesian coordinate system. The X-axis, Y-axis, and Z-axis are mutually perpendicular. The direction in which the X-axis extends is called the "X-direction," the direction in which the Y-axis extends is called the "Y-direction," and the direction in which the Z-axis extends is called the "Z-direction." For ease of explanation, the arrow direction in the Z-direction is called upward and the opposite direction is called downward, but these directions are unrelated to the direction of gravity. Viewing in the direction along the Z-direction is called "planar view."

[0010] <Light emitting element> FIG. 1 is a plan view illustrating a schematic view of a light emitting device according to an embodiment. FIG. 2 is a plan view illustrating the arrangement of a conductive member and a reflective layer of the light emitting device according to the embodiment. FIG. 3 is a cross-sectional view illustrating a schematic view of the light-emitting device according to the embodiment. FIG. 4 is an enlarged cross-sectional view that illustrates a part of the light-emitting device according to the embodiment. FIG. 3 is a cross-sectional view taken along line III-III shown in FIG. FIG. 4 is an enlarged view of the region R1 shown in FIG.

[0011] As shown in FIGS. 1 to 4, the light emitting device 100 according to the embodiment includes a conductive member 10, a reflective layer 20, an insulating layer 30, a semiconductor structure 40, an n-electrode 50, and a p-electrode 60.

[0012] (Conductive material) The conductive member 10 is disposed under the insulating layer 30. The conductive member 10 has a first conductive layer 11 and a second conductive layer 12. The second conductive layer 12 is disposed on the first conductive layer 11. The second conductive layer 12 is in contact with the upper surface of the first conductive layer 11 and covers the upper surface of the first conductive layer 11. A part of the second conductive layer 12 is disposed between the first conductive layer 11 and the insulating layer 30. Another part of the second conductive layer 12 is disposed between the first conductive layer 11 and the p-type semiconductor layer 41. The second conductive layer 12 is in contact with the p-type semiconductor layer 41. The second conductive layer 12 is electrically connected to the p-type semiconductor layer 41. The shape of the conductive member 10 in a plan view is, for example, rectangular. The upper and lower surfaces of the conductive member 10, excluding the part disposed inside the second through hole 30h described later, are surfaces approximately parallel to the XY plane.

[0013] The second conductive layer 12 may be disposed on at least a portion of the first conductive layer 11. In other words, the second conductive layer 12 does not have to be disposed on a portion of the first conductive layer 11. The second conductive layer 12 is not disposed between the first conductive layer 11 and the p-electrode 60. The first conductive layer 11 is in contact with the p-electrode 60. The first conductive layer 11 is electrically connected to the p-electrode 60.

[0014] The conductive member 10 has a first through hole 10h. The first through hole 10h penetrates the conductive member 10 in the Z direction. The first through hole 10h has a circular shape in a plan view. When the first through hole 10h has a circular shape in a plan view, the diameter of the first through hole 10h is not less than 10 μm and not more than 20 μm.

[0015] Moreover, the conductive member 10 has a first region 10a and a second region 10b. The first region 10a overlaps with the semiconductor structure 40 in a planar view. The second region 10b does not overlap with the semiconductor structure 40 in a planar view. The p-electrode 60 is disposed in the second region 10b. That is, the p-electrode 60 is disposed at a position that does not overlap with the semiconductor structure 40 in a planar view. The p-electrode 60 may be disposed in the first region 10a. That is, the p-electrode 60 may be disposed at a position that overlaps with the semiconductor structure 40 in a planar view.

[0016] Moreover, the first region 10a of the conductive member 10 has a plurality of first portions 16. The first portions 16 overlap the second through holes 30h in a plan view. A part of the first portions 16 is located inside the second through holes 30h. The shape of the first portions 16 in a plan view is circular. The shape of the first portions 16 in a plan view may be, for example, a polygon. When the shape of the first portions 16 in a plan view is circular, the diameter of the first portions 16 is 10 μm or more and 20 μm or less. The areas of the plurality of first portions 16 in a plan view are the same. The areas of the plurality of first portions 16 in a plan view do not have to be the same.

[0017] The first region 10a of the conductive member 10 is disposed only at a position overlapping with the second through hole 30h in a plan view. By disposing the first region 10a of the conductive member 10 only at a position overlapping with the second through hole 30h, it is possible to reduce light absorption by the conductive member 10 and improve the light extraction efficiency.

[0018] Moreover, the first region 10a of the conductive member 10 is disposed only at a position that does not overlap with the n-electrode 50 and the n-type semiconductor layer 43 in a plan view. By disposing the first region 10a of the conductive member 10 only at a position that does not overlap with the n-electrode 50 and the n-type semiconductor layer 43, it is possible to reduce light absorption by the conductive member 10 and improve the light extraction efficiency.

[0019] The conductive member 10 includes a conductive material such as a metal. The first conductive layer 11 may include, for example, gold, silver, copper, aluminum, rhodium, ruthenium, or the like. The first conductive layer 11 includes, for example, gold. The thickness of the first conductive layer 11 is, for example, 300 nm or more and 400 nm or less. The second conductive layer 12 may include, for example, indium tin oxide, indium zinc oxide, gallium zinc oxide, aluminum zinc oxide, or the like. The second conductive layer 12 includes, for example, indium tin oxide. The thickness of the second conductive layer 12 is, for example, 100 nm or more and 200 nm or less.

[0020] (reflective layer) The reflective layer 20 is disposed inside the first through hole 10h. The reflective layer 20 is in contact with the conductive member 10. The reflective layer 20 is disposed in each region where the first through holes 10h are disposed in a plan view.

[0021] The reflective layer 20 is, for example, a dielectric multilayer film. The reflective layer 20 is, for example, a dielectric multilayer film having a layer made of silicon dioxide and a layer made of niobium oxide. The reflective layer 20 may contain, for example, titanium oxide. The thickness of the reflective layer 20 is, for example, 500 nm or more and 1000 nm or less.

[0022] The reflectance of the reflective layer 20 at the peak wavelength of the light emitted by the light emitting layer 42 is higher than the reflectance of the conductive member 10 at the peak wavelength of the light emitted by the light emitting layer 42. The reflectance of the reflective layer 20 at the peak wavelength of the light emitted by the light emitting layer 42 is, for example, 70% or more, preferably 80% or more. The reflectance of the conductive member 10 at the peak wavelength of the light emitted by the light emitting layer 42 is, for example, 60% or more, preferably 70% or more. The reflectance value is measured, for example, by an absolute reflectance measuring device. As the absolute reflectance measuring device, for example, an "Absolute Reflectance Measuring System manufactured by Shimadzu Corporation" can be used.

[0023] Furthermore, at least a portion of the reflective layer 20 is disposed in a position overlapping with the light emitting layer 42 in a planar view. A portion of the reflective layer 20 may be disposed in a position not overlapping with the light emitting layer 42 in a planar view.

[0024] By disposing the reflective layer 20 at a position overlapping with the light emitting layer 42, the light emitted from the light emitting layer 42 and proceeding toward the reflective layer 20 can be reflected toward the p-type semiconductor layer 41 by the reflective layer 20. This can improve the light extraction efficiency compared to the case where the reflective layer 20 is not disposed.

[0025] Furthermore, the reflective layer 20 has a first reflective portion 21 and a second reflective portion 22. The first reflective portion 21 overlaps with the n-electrode 50 in a planar view. The second reflective portion 22 does not overlap with the n-electrode 50 in a planar view.

[0026] At a position overlapping with the n-electrode 50 in a planar view, light from the light-emitting layer 42 is likely to be blocked by the n-electrode 50. By having the reflective layer 20 have the first reflective portion 21 overlapping with the n-electrode 50 in a planar view and the second reflective portion 22 not overlapping with the n-electrode 50 in a planar view, it is possible to improve the light extraction efficiency not only in the portion where the light from the light-emitting layer 42 is likely to be blocked, but also in the portion where the light from the light-emitting layer 42 is not likely to be blocked.

[0027] (insulating layer) An insulating layer 30 is disposed on the conductive member 10 and the reflective layer 20. The insulating layer 30 is in contact with the conductive member 10 and the reflective layer 20. The thickness of the insulating layer 30 is, for example, 100 μm or more and 300 μm or less. The upper and lower surfaces of the insulating layer 30 are surfaces that are approximately parallel to the XY plane. The insulating layer 30 has a second through hole 30h. The second through hole 30h penetrates the insulating layer 30 in the Z direction. The second through hole 30h is disposed at a position that does not overlap with the first through hole 10h in a plan view. The second through hole 30h is disposed at a position that does not overlap with the reflective layer 20. A part of the conductive member 10 is disposed inside the second through hole 30h.

[0028] The number of the second through holes 30h may be one or more. The plurality of second through holes 30h are arranged in a matrix in the X direction and the Y direction. This is not limiting, and for example, the plurality of second through holes 30h may be arranged in a staggered pattern.

[0029] The insulating layer 30 includes an insulating material. The insulating layer 30 includes, for example, silicon dioxide. The insulating layer 30 may include, for example, at least one of silicon nitride and silicon oxynitride.

[0030] (Semiconductor Structure) The semiconductor structure 40 is disposed on the insulating layer 30. The semiconductor structure 40 is in contact with the insulating layer 30. The semiconductor structure 40 has a p-type semiconductor layer 41, a light emitting layer 42, and an n-type semiconductor layer 43. The n-type semiconductor layer 43 includes a first layer 431 and a second layer 432 partially disposed on the first layer 431. The p-type semiconductor layer 41 is disposed on the insulating layer 30. The p-type semiconductor layer 41 is in contact with the insulating layer 30. The light emitting layer 42 is disposed on the p-type semiconductor layer 41. The light emitting layer 42 is in contact with the p-type semiconductor layer 41 and the first layer 431 of the n-type semiconductor layer 43. A part of the conductive member 10 is in contact with the p-type semiconductor layer 41 in the second through hole 30h. In other words, the part of the conductive member 10 disposed inside the second through hole 30h is in contact with the p-type semiconductor layer 41. The upper and lower surfaces of the p-type semiconductor layer 41, the light emitting layer 42, and the n-type semiconductor layer 43 are each substantially parallel to the XY plane.

[0031] The semiconductor structure 40 emits, for example, red light. In this case, the p-type semiconductor layer 41 includes, for example, GaP (gallium phosphide). The light emitting layer 42 includes, for example, AlGaInP (aluminum indium gallium phosphide) and GaInP (gallium indium phosphide). The first layer 431 of the n-type semiconductor layer 43 includes, for example, AlGaInP. The second layer 432 of the n-type semiconductor layer 43 includes, for example, GaAs (gallium arsenide). The p-type semiconductor layer 41, the light emitting layer 42, and the n-type semiconductor layer 43 are not limited thereto, and may be a combination of other semiconductor layers that emit red light. The peak wavelength of the light emitted by the light emitting layer 42 is, for example, 620 nm or more and 700 nm or less.

[0032] Since the band gap energy of the second layer 432 is smaller than the band gap energy of the first layer 431, the second layer 432 is more likely to absorb light emitted by the light emitting layer 42 than the first layer 431. By disposing the second layer 432 partially on the first layer 431, it is possible to reduce light absorption by the second layer 432. In consideration of the light absorption by the second layer 432, it is preferable that the thickness of the second layer 432 is thinner than the thickness of the first layer 431. The thickness of the first layer 431 is, for example, 2 μm or more and 4 μm or less, and the thickness of the second layer 432 is, for example, 0.05 μm or more and 0.5 μm or less.

[0033] (n electrode) An n-electrode 50 is disposed on the n-type semiconductor layer 43. The n-electrode 50 is in contact with the n-type semiconductor layer 43. The n-electrode 50 is electrically connected to the n-type semiconductor layer 43. The upper and lower surfaces of the n-electrode 50 are surfaces that are approximately parallel to the XY plane.

[0034] The n-electrode 50 has a pad portion 51 and an extension portion 52. The shape of the pad portion 51 in a plan view is, for example, a circle. The extension portion 52 extends from the pad portion 51 in a plan view. The second layer 432 of the n-type semiconductor layer 43 has a first semiconductor portion 43a and a second semiconductor portion 43b. The first semiconductor portion 43a overlaps with the pad portion 51 in a plan view. The second semiconductor portion 43b overlaps with the extension portion 52 in a plan view. The first reflective portion 21 of the reflective layer 20 overlaps with the pad portion 51 and the extension portion 52 in a plan view.

[0035] In a plan view, in a region where the light emitting layer 42 overlaps with the pad portion 51 and the extension portion 52 of the n-electrode 50, light from the light emitting layer 42 is likely to be blocked by the pad portion 51 and the extension portion 52 of the n-electrode 50. By arranging the first reflective portion 21 so as to overlap with each of the pad portion 51 and the extension portion 52 in a plan view, it is possible to increase the reflective area while reducing the light emission in the light emitting layer 42 overlapping with the pad portion 51 and the extension portion 52, and therefore it is possible to improve the light extraction efficiency.

[0036] The n-electrode 50 includes a conductive material such as a metal, and may be made of, for example, gold, silver, platinum, titanium, nickel, germanium, rhodium, or ruthenium.

[0037] (p electrode) A p-electrode 60 is disposed on a portion of the conductive member 10 on which the insulating layer 30, the semiconductor structure 40, and the n-electrode 50 are not disposed. The p-electrode 60 is in contact with the conductive member 10. The p-electrode 60 is electrically connected to the conductive member 10. The upper and lower surfaces of the p-electrode 60 are surfaces approximately parallel to the XY plane.

[0038] The p-electrode 60 includes a conductive material such as a metal, and may be made of, for example, gold, silver, platinum, titanium, nickel, germanium, rhodium, or ruthenium.

[0039] The light-emitting layer 42 emits light when a voltage is applied between the n-electrode 50 and the p-electrode 60. This allows the light-emitting element 100 to emit light.

[0040] The light emitting element 100 further includes a substrate 70, a bonding member 72, and a reflective metal layer 74. The light emitting element 100 may include each of the substrate 70, the bonding member 72, and the reflective metal layer 74 as necessary, or may be omitted.

[0041] The shape of the substrate 70 in a plan view is, for example, rectangular. The substrate 70 includes, for example, at least one of silicon and aluminum nitride. The substrate 70 may be, for example, a substrate including sapphire. When the shape of the substrate 70 in a plan view is rectangular, the length of one side is, for example, 200 μm or more and 1000 μm or less. The upper and lower surfaces of the substrate 70 are surfaces that are approximately parallel to the XY plane. The thickness of the substrate 70 is, for example, 100 μm or more and 500 μm or less.

[0042] A bonding member 72 is disposed on the substrate 70. The bonding member 72 is located between the substrate 70 and the conductive member 10 in the Z direction. The bonding member 72 is in contact with the substrate 70. The bonding member 72 has a rectangular shape in a plan view, for example. The upper and lower surfaces of the bonding member 72 are surfaces that are approximately parallel to the XY plane. The bonding member 72 bonds the substrate 70 and the reflective metal layer 74 together.

[0043] The joining members 72 may be made of a solder material containing, for example, AuSn, NiSn, AgSn, or the like as a main component.

[0044] A reflective metal layer 74 is disposed on the bonding member 72. A conductive member 10 and a reflective layer 20 are disposed on the reflective metal layer 74. A part of the reflective metal layer 74 is located between the bonding member 72 and the conductive member 10 in the Z direction. Another part of the reflective metal layer 74 is located between the bonding member 72 and the reflective layer 20 in the Z direction. The reflective metal layer 74 is in contact with the bonding member 72. A part of the reflective metal layer 74 is in contact with the conductive member 10. The other part of the reflective metal layer 74 is in contact with the reflective layer 20. The shape of the reflective metal layer 74 in a plan view is, for example, rectangular. The upper and lower surfaces of the reflective metal layer 74 are surfaces that are approximately parallel to the XY plane.

[0045] The reflectance of the reflective metal layer 74 at the peak wavelength of the light emitted by the light emitting layer 42 is, for example, higher than the reflectance of the conductive member 10 at the peak wavelength of the light emitted by the light emitting layer 42. The reflectance of the reflective metal layer 74 at the peak wavelength of the light emitted by the light emitting layer 42 is, for example, 60% or more, and preferably 70% or more. The reflective metal layer 74 can be made of, for example, aluminum, gold, platinum, silver, copper, rhodium, ruthenium, or the like.

[0046] Modifications of the embodiment will be described below. 5 and 7 to 10 are plan views each showing a schematic arrangement of a conductive member and a reflective layer of a light-emitting element according to a first to fifth modified example of the embodiment. FIG. 6 is a cross-sectional view diagrammatically illustrating a light-emitting device according to a first modified example of the embodiment. FIG. 11 is a cross-sectional view diagrammatically illustrating a light-emitting device according to a fifth modified example of the embodiment. FIG. 11 is a cross-sectional view taken along line XI-XI shown in FIG.

[0047] As shown in Figs. 5 to 11, in the first to fifth modified examples, the first region 10a of the conductive member 10 has second portions 17 in addition to the above-mentioned first portions 16. The second portions 17 do not overlap the second through holes 30h in a plan view. The second portions 17 connect the first portions 16 adjacent to each other in the X and Y directions. In other words, in the first to fifth modified examples, the first region 10a of the conductive member 10 is arranged in a lattice pattern extending in the X and Y directions in a plan view. Intersections of the lattices of the first region 10a arranged in a lattice pattern overlap the second through holes 30h in a plan view.

[0048] By positioning the first region 10a of the conductive member 10 not only at a position overlapping with the second through hole 30h, but also at a position not overlapping with the second through hole 30h, it becomes easier to diffuse current over a wider range in the semiconductor structure 40, so that the current density distribution in the semiconductor structure 40 can be made more uniform.

[0049] 5, 8, and 9, in the first, third, and fourth modified examples, the first region 10a of the conductive member 10 is disposed only at a position that does not overlap with the n-electrode 50 and the second layer 432 of the n-type semiconductor layer 43 in a planar view. In contrast, as shown in FIGS. 7 and 10, in the second and fifth modified examples, the first region 10a of the conductive member 10 is disposed at a position that does not overlap with the n-electrode 50 and the second layer 432 of the n-type semiconductor layer 43 in a planar view, as well as at a position that overlaps with the n-electrode 50 and the second layer 432 of the n-type semiconductor layer 43.

[0050] By disposing the first region 10a of the conductive member 10 at a position where it overlaps with the n-electrode 50 and the second layer 432 of the n-type semiconductor layer 43, in addition to a position where it does not overlap with the n-electrode 50 and the second layer 432 of the n-type semiconductor layer 43, the region where the p-type semiconductor layer 41 and the conductive member 10 are conductive is increased, making it easier to diffuse current over a wider range in the semiconductor structure 40. This makes it possible to make the current density distribution in the semiconductor structure 40 more uniform.

[0051] Moreover, as shown in Figures 5, 7, and 10, in each of the first, second, and fifth modified examples, the area of ​​the first portion 16 in a planar view is the same, and the width of the second portion 17 in a planar view is the same.

[0052] By making the areas of the first portions 16 equal to each other in a plan view and making the widths of the second portions 17 equal to each other in a plan view, it is possible to reduce bias in the current density distribution in the semiconductor structure 40.

[0053] 8, in the third modified example, the areas of the first portions 16 in a plan view are the same, and the widths of the second portions 17 in a plan view are partially different. More specifically, in the third modified example, the width of the second portion 17 located near the n-electrode 50 in a plan view is smaller than the width of the second portion 17 located near the p-electrode 60 in a plan view. As a result, in the third modified example, the ratio of the area of ​​the reflective layer 20 to the area of ​​the conductive member 10 per unit area decreases from the n-electrode 50 to the p-electrode 60 in a plan view. The width of the second portion 17 is, for example, not less than 10 μm and not more than 20 μm.

[0054] 9, in the fourth modified example, the widths of the second portions 17 in a plan view are the same, and part of the area of ​​the first portions 16 in a plan view is made different. More specifically, in the fourth modified example, the area of ​​the first portions 16 in a plan view increases from the n-electrode 50 toward the p-electrode 60 in a plan view. As a result, in the fourth modified example, the ratio of the area of ​​the reflective layer 20 to the area of ​​the conductive member 10 per unit area decreases from the n-electrode 50 toward the p-electrode 60 in a plan view.

[0055] 10 and 11, in the fifth modification, the first region 10a of the conductive member 10 has a third portion 18 in addition to the first portion 16 and the second portion 17 described above. The third portion 18 does not have a first through hole 10h. In the fifth modification, the first portion 16 and the second portion 17 are disposed in a position close to the n-electrode 50, and the third portion 18 is disposed in a position close to the p-electrode 60. That is, in the fifth modification, the reflective layer 20 is disposed only in a position close to the n-electrode 50, and the reflective layer 20 is not disposed in a position close to the p-electrode 60. As a result, in the fifth modification, the ratio of the area of ​​the reflective layer 20 to the area of ​​the conductive member 10 per unit area decreases from the n-electrode 50 to the p-electrode 60 in a plan view.

[0056] In this way, by making the ratio of the area of ​​the reflective layer 20 to the area of ​​the conductive member 10 per unit area decrease from the n-electrode 50 toward the p-electrode 60 in a planar view, the reflective layer 20 can improve the light extraction efficiency in a position close to the n-electrode 50, while making it easier to diffuse the current in a position away from the n-electrode 50.

[0057] <Method of manufacturing light-emitting element> 12 to 17 are cross-sectional views that diagrammatically show a method for manufacturing a light-emitting device according to an embodiment. 12 to 15 are performed, for example, with the top-bottom orientation reversed from that of Fig. 3. The steps of Fig. 16 and Fig. 17 are performed, for example, with the top-bottom orientation the same as that of Fig. 3. The top-bottom orientation in each step is not limited to this.

[0058] In the method for manufacturing the light emitting device according to the embodiment, first, as shown in FIG. 12, a step of preparing a laminate 48 and forming an insulating layer 30 on the laminate 48 is performed.

[0059] The laminate 48 has a first base material 46, a second base material 47 located on the first base material 46, an n-type semiconductor layer 43 located on the second base material 47, a light emitting layer 42 located on the n-type semiconductor layer 43, and a p-type semiconductor layer 41 located on the light emitting layer 42. The first base material 46 is, for example, a substrate containing GaAs (gallium arsenide). The second base material 47 is, for example, a semiconductor layer containing GaInP (gallium indium phosphide).

[0060] After preparing the laminate 48, the insulating layer 30 having the second through hole 30h is formed in the p-type semiconductor layer 41 of the laminate 48. The insulating layer 30 having the second through hole 30h can be formed, for example, by forming the insulating layer 30 on the p-type semiconductor layer 41 and forming the second through hole 30h in a part of the insulating layer 30.

[0061] 13, the method for manufacturing the light-emitting element according to the embodiment next includes a step of forming a second conductive layer 12 on the insulating layer 30. A portion of the second conductive layer 12 is formed inside the second through hole 30h so as to be in contact with the p-type semiconductor layer 41.

[0062] 14, the method for manufacturing the light-emitting element according to the embodiment next performs a step of forming a first conductive layer 11 on the second conductive layer 12. Then, a step of removing a part of the first conductive layer 11 and a part of the second conductive layer 12 to form a first through hole 10h exposing the insulating layer 30 is performed. Also, a step of forming a reflective layer 20 inside the first through hole 10h so as to be in contact with the insulating layer 30 is performed.

[0063] 15, the method for manufacturing the light emitting device according to the embodiment next performs a step of forming a reflective metal layer 74 on the first conductive layer 11 and the reflective layer 20. Then, a step of forming a bonding member 72 on the reflective metal layer 74 is performed. Then, a step of bonding the reflective metal layer 74 and the substrate 70 with the bonding member 72 is performed.

[0064] 16, the method for manufacturing the light-emitting element according to the embodiment next performs a step of removing the first base material 46 and the second base material 47, and also removing a part of the n-type semiconductor layer 43, a part of the light-emitting layer 42, a part of the p-type semiconductor layer 41, and a part of the insulating layer 30. By performing this step, a semiconductor structure 40 is formed, which includes the n-type semiconductor layer 43 including the first layer 431 and the second layer 432, the light-emitting layer 42, and the p-type semiconductor layer 41.

[0065] 17, the method for manufacturing the light-emitting device according to the embodiment next performs a step of forming an n-electrode 50 on the n-type semiconductor layer 43. In addition, a step of removing a portion of the second conductive layer 12 and forming a p-electrode 60 on the first conductive layer 11 is performed. In this manner, the light-emitting device 100 is manufactured.

[0066] The first conductive layer 11, the second conductive layer 12, the reflective layer 20, the insulating layer 30, the n-electrode 50, the p-electrode 60, and the reflective metal layer 74 can be formed by, for example, a sputtering method or a vapor deposition method. For example, dry etching or wet etching can be used to remove the insulating layer 30, the first conductive layer 11, and the second conductive layer 12. For example, wet etching can be used to remove the first substrate 46 and the second substrate 47. For example, dry etching or wet etching can be used to remove the p-type semiconductor layer 41, the light emitting layer 42, and the n-type semiconductor layer 43.

[0067] The embodiment may include the following features.

[0068] (Configuration 1) A conductive member having a first through hole; a reflective layer disposed inside the first through hole; an insulating layer disposed on the conductive member and the reflective layer, the insulating layer having a second through hole disposed at a position not overlapping with the first through hole in a plan view; a semiconductor structure including a p-type semiconductor layer disposed on the insulating layer, a light emitting layer disposed on the p-type semiconductor layer, and an n-type semiconductor layer disposed partially on the light emitting layer; an n-electrode disposed on the n-type semiconductor layer and electrically connected to the n-type semiconductor layer; a p-electrode electrically connected to the conductive member; Equipped with a reflectance of the reflective layer at a peak wavelength of the light emitted by the light emitting layer is higher than a reflectance of the conductive member at the peak wavelength of the light emitted by the light emitting layer; a portion of the conductive member contacts the p-type semiconductor layer in the second through hole; A light-emitting element, wherein at least a portion of the reflective layer is disposed at a position overlapping with the light-emitting layer in a plan view.

[0069] (Configuration 2) 2. The light-emitting element according to claim 1, wherein, in a plan view, the reflective layer has a first reflective portion that overlaps with the n-electrode and a second reflective portion that does not overlap with the n-electrode.

[0070] (Configuration 3) In a plan view, the n-electrode has a pad portion and an extension portion extending from the pad portion, In a plan view, the n-type semiconductor layer has a first semiconductor portion overlapping the pad portion and a second semiconductor portion overlapping the extension portion, 3. The light-emitting element according to claim 2, wherein the first reflective portion overlaps with the pad portion and the extension portion in a plan view.

[0071] (Configuration 4) In a plan view, the conductive member has a first region that overlaps with the semiconductor structure and a second region that does not overlap with the semiconductor structure; the p-electrode is disposed in the second region, The light-emitting device according to any one of configurations 1 to 3, wherein in a plan view, the ratio of the area of ​​the reflective layer to the area of ​​the conductive member per unit area decreases from the n-electrode to the p-electrode.

[0072] (Configuration 5) 5. The light-emitting device according to any one of configurations 1 to 4, wherein the reflective layer is a dielectric multilayer film.

[0073] (Configuration 6) The light-emitting element according to any one of configurations 1 to 5, further comprising: a substrate; a bonding member located between the substrate and the conductive member; and a reflective metal layer located between the bonding member and the conductive member.

[0074] (Configuration 7) the conductive member includes a first conductive layer including gold and a second conductive layer including indium tin oxide disposed on the first conductive layer; the first conductive layer is electrically connected to the p-electrode; 7. The light-emitting device according to any one of configurations 1 to 6, wherein the second conductive layer is electrically connected to the p-type semiconductor layer.

[0075] (Configuration 8) the p-type semiconductor layer contains GaP, the n-type semiconductor layer includes GaAs, The light-emitting device according to any one of configurations 1 to 7, wherein the light-emitting layer contains AlGaInP.

[0076] As described above, according to the embodiment, a light emitting element capable of improving light extraction efficiency is provided.

[0077] The above-described embodiments are examples of the present invention, and the present invention is not limited to these embodiments. For example, the present invention also includes the above-described embodiments in which some components or steps are added, deleted, or changed. In addition, the above-described embodiments can be implemented in combination with each other. [Industrial Applicability]

[0078] The present invention can be used, for example, as a light source for a lighting device or a display device, an in-vehicle light source, and the like. [Explanation of symbols]

[0079] 10: Conductive material 10a: 1st area 10b:Second area 10h: 1st through hole 11: First conductive layer 12: Second conductive layer 16: Part 1 17:Second part 18: 3rd part 20: Reflective layer 21: 1st reflective part 22:Second reflective part 30: Insulating layer 30h: 2nd through hole 40: Semiconductor structure 41: p-type semiconductor layer 42: Light-emitting layer 43: n-type semiconductor layer 43a: first semiconductor portion 43b: second semiconductor portion 431: 1st layer 432:Second layer 46:First base material 47:Second base material 48:Laminate 50:n electrode 51: Pad part 52: Stretched part 60:p electrode 70: Substrate 72: Joint material 74:Reflective metal layer 100: Light emitting element R1: area

Claims

1. A conductive member having a first through hole; a reflective layer disposed inside the first through hole; an insulating layer disposed on the conductive member and the reflective layer, the insulating layer having a second through hole disposed at a position not overlapping with the first through hole in a plan view; a semiconductor structure including a p-type semiconductor layer disposed on the insulating layer, a light emitting layer disposed on the p-type semiconductor layer, and an n-type semiconductor layer disposed partially on the light emitting layer; an n-electrode disposed on the n-type semiconductor layer and electrically connected to the n-type semiconductor layer; a p-electrode electrically connected to the conductive member; Equipped with a reflectance of the reflective layer at a peak wavelength of the light emitted by the light emitting layer is higher than a reflectance of the conductive member at the peak wavelength of the light emitted by the light emitting layer; a portion of the conductive member contacting the p-type semiconductor layer at the second through hole; A light-emitting element, wherein at least a portion of the reflective layer is disposed at a position overlapping with the light-emitting layer in a plan view.

2. The light-emitting element according to claim 1 , wherein the reflective layer has, in a plan view, a first reflective portion that overlaps with the n-electrode and a second reflective portion that does not overlap with the n-electrode.

3. In a plan view, the n-electrode has a pad portion and an extension portion extending from the pad portion, In a plan view, the n-type semiconductor layer has a first semiconductor portion overlapping the pad portion and a second semiconductor portion overlapping the extension portion, The light-emitting element according to claim 2 , wherein the first reflective portion overlaps with the pad portion and the extension portion in a plan view.

4. In a plan view, the conductive member has a first region overlapping the semiconductor structure and a second region not overlapping the semiconductor structure; the p-electrode is disposed in the second region, 4. The light-emitting device according to claim 1, wherein in a plan view, the ratio of an area of ​​the reflective layer to an area of ​​the conductive member per unit area decreases from the n-electrode toward the p-electrode.

5. 4. The light-emitting device according to claim 1, wherein the reflective layer is a dielectric multilayer film.

6. The light-emitting element according to any one of claims 1 to 3, further comprising: a substrate; a bonding member located between the substrate and the conductive member; and a reflective metal layer located between the bonding member and the conductive member.

7. the conductive member includes a first conductive layer including gold and a second conductive layer including indium tin oxide disposed on the first conductive layer; the first conductive layer is electrically connected to the p-electrode; 4. The light-emitting element according to claim 1, wherein the second conductive layer is electrically connected to the p-type semiconductor layer.

8. the p-type semiconductor layer contains GaP, the n-type semiconductor layer includes GaAs, 4. The light-emitting device according to claim 1, wherein the light-emitting layer contains AlGaInP.

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