Method for manufacturing light emitting element, and light emitting element

Abstract

The present invention provides: a method for manufacturing a light emitting element, with which it is possible to improve luminance; and a light emitting element.　This method for manufacturing a light emitting element comprises: a step for preparing a wafer which has a first insulating film that is disposed on a second semiconductor layer of a semiconductor structure, a first electrode that is disposed on the first insulating film, and a second electrode that is disposed on the first insulating film and is connected to the second semiconductor layer in an opening of the first insulating film; a step for removing a part of the semiconductor structure from the upper surface side of the first semiconductor layer, and separating the semiconductor structure into a plurality of light emitting units so that the first electrode has a first portion that is positioned outside the outer edges of the light emitting units in a plan view; a step for removing a part of the first insulating film so as to expose the first portion of the first electrode from the first insulating film, and removing a part of a second insulating film that covers the light emitting units so as expose a part of the first semiconductor layer from the second insulating film; and a step for forming, on the second insulating film, a first wiring line that electrically connects the part of the first semiconductor layer exposed from the second insulating film and the first portion of the first electrode exposed from the first insulating film.

Description

Light-emitting device manufacturing method and light-emitting device

[0001] The present invention relates to a method for manufacturing a light-emitting element and a light-emitting element.

[0002] Patent Document 1 discloses a light-emitting element having a first electrode disposed on a main light extraction surface of the light-emitting layer, and a second electrode disposed on a surface of the light-emitting layer opposite to the main light extraction surface.

[0003] JP 2015-32809 A

[0004] An object of the present invention is to provide a method for manufacturing a light-emitting device capable of improving brightness, and a light-emitting device.

[0005] According to one aspect of the present invention, a method for manufacturing a light-emitting element includes the steps of: preparing a wafer having a first substrate; a semiconductor structure disposed on the first substrate, the semiconductor structure having a first semiconductor layer, a second semiconductor layer disposed farther from the first substrate than the first semiconductor layer, and an active layer located between the first semiconductor layer and the second semiconductor layer; a first insulating film disposed on the second semiconductor layer and having an opening located above the second semiconductor layer; a first electrode disposed on the first insulating film; and a second electrode disposed on the first insulating film and spaced apart from the first electrode, the second electrode being electrically connected to the second semiconductor layer through the opening; bonding a side of the wafer on which the second electrode and the first electrode are disposed to a second substrate; removing the first substrate after bonding the wafer to the second substrate to expose an upper surface of the first semiconductor layer; the first electrode has a first portion located outside an outer edge of the light-emitting portion in a plan view; forming a second insulating film covering the light-emitting portion; removing a portion of the first insulating film to expose the first portion of the first electrode from the first insulating film and removing a portion of the second insulating film to expose a portion of the first semiconductor layer of the light-emitting portion from the second insulating film; forming a first wiring on the second insulating film that electrically connects the portion of the first semiconductor layer exposed from the second insulating film and the first portion of the first electrode exposed from the first insulating film; and, after forming the first wiring, separating the light-emitting portion from the second substrate.

[0006] According to one aspect of the present invention, a light-emitting element includes: a semiconductor structure having a first surface, a second surface located opposite to the first surface, and a side surface connecting the first surface and the second surface, the semiconductor structure having a first semiconductor layer located on the first surface side, a second semiconductor layer located on the second surface side, and an active layer located between the first semiconductor layer and the second semiconductor layer; a first insulating film disposed on the second surface and having an opening disposed at a position overlapping with the second surface in a planar view; a first electrode disposed on the first insulating film and not connected to the second surface, the first electrode having a first portion located outside an outer edge of the semiconductor structure in a planar view; a second electrode disposed on the first insulating film and spaced apart from the first electrode and electrically connected to the second semiconductor layer on the second surface through the opening; a second insulating film disposed on the first surface and on the side surface of the semiconductor structure; and a first wiring disposed on the second insulating film and electrically connecting a portion of the first semiconductor layer exposed from the second insulating film to the first portion of the first electrode exposed from the first insulating film.

[0007] According to the present invention, it is possible to provide a method for manufacturing a light-emitting device and a light-emitting device capable of improving brightness.

[0008] FIG. 1 is a schematic top view of the light-emitting element according to the first embodiment. FIG. 2 is a schematic bottom view of the light-emitting element according to the first embodiment. FIG. 3 is a schematic cross-sectional view taken along line II-II of FIG. 1. FIG. 4 is a schematic cross-sectional view illustrating one step of a method for manufacturing the light-emitting element according to the first embodiment. FIG. 5 is a schematic cross-sectional view illustrating one step of a method for manufacturing the light-emitting element according to the first embodiment. FIG. 6 is a schematic cross-sectional view illustrating one step of a method for manufacturing the light-emitting element according to the first embodiment. FIG. 7 is a schematic cross-sectional view illustrating one step of a method for manufacturing the light-emitting element according to the first embodiment. FIG. 8 is a schematic cross-sectional view illustrating one step of a method for manufacturing the light-emitting element according to the first embodiment. FIG. 9 is a schematic cross-sectional view illustrating one step of a method for manufacturing the light-emitting element according to the first embodiment. FIG. 11 is a schematic cross-sectional view illustrating one step of a method for manufacturing the light-emitting element according to the first embodiment. FIG. 21B is a schematic cross-sectional view illustrating one step of the manufacturing method for the light-emitting element according to the second embodiment. FIG. 21C is a schematic cross-sectional view illustrating one step of the manufacturing method for the light-emitting element according to the second embodiment. FIG. 21D is a schematic bottom view of the light-emitting element according to the third embodiment. FIG. 21E is a schematic cross-sectional view taken along line XXIB-XXIB of FIG. 21A. FIG. 21F is a schematic cross-sectional view illustrating one step of the manufacturing method for the light-emitting element according to the third embodiment. FIG. 21G is a schematic cross-sectional view illustrating one step of the manufacturing method for the light-emitting element according to the third embodiment. FIG. 21H is a schematic cross-sectional view illustrating one step of the manufacturing method for the light-emitting element according to the third embodiment.

[0009] Hereinafter, embodiments will be described with reference to the drawings. The dimensions, materials, shapes, relative arrangements, and the like of components described in the embodiments are not intended to be limiting unless otherwise specified, and are merely illustrative examples. The sizes and positional relationships of components shown in each drawing may be exaggerated for clarity. In the following description, the same names and symbols indicate the same or similar components, and detailed descriptions will be omitted as appropriate. In addition, cross-sectional views may be shown as end views showing only the cut surface. In addition, in cross-sectional views, the cross sections of the semiconductor structure are not hatched to make the boundaries of each layer of the semiconductor structure easier to see.

[0010] In the following description, terms indicating specific directions or positions (e.g., "above," "below," and other terms including these terms) may be used. However, these terms are used merely to facilitate understanding of relative directions or positions in the referenced drawings. As long as the relative direction or position relationship indicated by terms such as "above" and "below" in the referenced drawings is the same, the arrangement in drawings other than those disclosed herein, actual products, etc., does not need to be the same as in the referenced drawings. In this specification, the positional relationship expressed as "above (or below)" includes, for example, when two components are assumed to exist, a case in which the two components are in contact with each other and a case in which the two components are not in contact with each other and one component is located above (or below) the other component. Furthermore, in this specification, unless otherwise specified, a component covering an object to be covered includes a case in which the component is in contact with the object to be covered and directly covers the object to be covered, and a case in which the component is not in contact with the object to be covered and indirectly covers the object to be covered.

[0011] [First embodiment] (Light-emitting element) A light-emitting element 1 according to a first embodiment will be described with reference to Figures 1A, 1B, and 2. In the top view of the light-emitting element 1 shown in Figure 1A and the bottom view of the light-emitting element 1 shown in Figure 1B, two directions perpendicular to each other are defined as a first direction X and a second direction Y. Furthermore, a direction perpendicular to the first direction X and the second direction Y is defined as a third direction Z. Figure 2 is a schematic cross-sectional view taken along line II-II in Figure 1.

[0012] The light-emitting element 1 includes a semiconductor structure 10 , a first insulating film 20 , a first electrode 31 , a second electrode 32 , a second insulating film 52 , and a first wiring 61 .

[0013] <Semiconductor Structure> The semiconductor structure 10 has a first surface 10b, a second surface 10a located on the opposite side of the first surface 10b in the third direction Z, and a side surface 10c connecting the first surface 10b and the second surface 10a. The semiconductor structure 10 has a first semiconductor layer 11 located on the first surface 10b side, a second semiconductor layer 13 located on the second surface 10a side, and an active layer 12 located between the first semiconductor layer 11 and the second semiconductor layer 13. The active layer 12 is a light-emitting layer that emits light and has, for example, an MQW (Multiple Quantum Well) structure including multiple barrier layers and multiple well layers. The active layer 12 emits light with a peak wavelength of, for example, 210 nm or more and 580 nm or less. For example, the first semiconductor layer 11 includes a semiconductor layer containing n-type impurities, and the second semiconductor layer 13 includes a semiconductor layer containing p-type impurities. Light emitted from the active layer 12 is emitted to the outside of the semiconductor structure 10 mainly from the first surface 10b and the side surface 10c.

[0014] On the second surface 10a side, the first semiconductor layer 11 has no portion exposed from the second semiconductor layer 13 and the active layer 12. The active layer 12 is in contact with the entire surface of the first semiconductor layer 11 located opposite the first surface 10b. This makes it possible to increase the area of ​​the active layer 12 in a planar view compared to when the first semiconductor layer 11 has an opening on the second surface 10a side that exposes a portion of the first semiconductor layer 11 from the second semiconductor layer 13 and the active layer 12, thereby improving the brightness of the light-emitting element 1.

[0015] The first surface 10b is a surface of the first semiconductor layer 11 located on the opposite side to the active layer 12. The second surface 10a is a surface of the second semiconductor layer 13 located on the opposite side to the active layer 12. The side surface 10c of the semiconductor structure 10 includes a side surface of the first semiconductor layer 11, a side surface of the active layer 12, and a side surface of the second semiconductor layer 13. In a plan view, the area of ​​the second surface 10a is larger than the area of ​​the first surface 10b. The active layer 12 is located closer to the second surface 10a than the first surface 10b. Therefore, since the area of ​​the second surface 10a is larger than the area of ​​the first surface 10b in a plan view, the area of ​​the active layer 12 in a plan view can be made larger than when the area of ​​the first surface 10b is larger than the area of ​​the second surface 10a in a plan view. In the example shown in Figure 2, in a cross-sectional view, the side surface 10c is inclined with respect to the first surface 10b and the second surface 10a so that the first surface 10b and the side surface 10c form an obtuse angle, and the second surface 10a and the side surface 10c form an acute angle.

[0016] In a plan view of the light-emitting element 1 (the top view shown in FIG. 1A or the bottom view shown in FIG. 1B), the shape of the outer edge 10d of the semiconductor structure 10 is, for example, a quadrangle. The outer edge 10d is the outer edge of the second surface 10a. The length of one side of the outer edge 10d is, for example, 5 μm or more and 150 μm or less. For example, the corners of the outer edge 10d can be rounded, and in that case, the length of one side of the outer edge 10d is the length of the straight portion of one side of the outer edge 10d.

[0017] The semiconductor structure 10 is made of a nitride semiconductor. In this specification, the term "nitride semiconductor" refers to, for example, In ｘ Al ｙ Ga １－ｘ－ｙ The term "nitride semiconductor" includes all semiconductors with compositions in which the composition ratios x and y in the chemical formula N (0≦x≦1, 0≦y≦1, x+y≦1) are varied within their respective ranges. Furthermore, in the above chemical formula, those that further contain a Group V element other than N (nitrogen) and those that further contain various elements added to control various physical properties such as conductivity type are also included in the term "nitride semiconductor."

[0018] <First insulating film> The first insulating film 20 is disposed on the second surface 10a of the semiconductor structure 10 and covers the second surface 10a. As shown in FIG. 1B , the first insulating film 20 has a first opening 20a that is disposed at a position that overlaps the second surface 10a of the semiconductor structure 10 in a plan view. In the example shown in FIG. 1B , the first insulating film 20 has one first opening 20a, but the first insulating film 20 may have multiple first openings 20a. In a plan view, an outer edge 20d of the first insulating film 20 is located outside the outer edge 10d of the semiconductor structure 10. In addition, the first insulating film 20 has a second opening 20b in a portion that is located outside the outer edge 10d of the semiconductor structure 10.

[0019] The first insulating film 20 may be, for example, a silicon oxide film or a silicon nitride film. The first insulating film 20 may also include a dielectric multilayer film. In this case, light traveling from the active layer 12 toward the second surface 10a can be reflected by the dielectric multilayer film and directed toward the first surface 10b and the side surface 10c. This improves the brightness of the light-emitting element 1. The reflectance of the dielectric multilayer film with respect to the peak wavelength of the light emitted by the active layer 12 is, for example, 60% or more, and preferably 70% or more. The first insulating film 20 may be, for example, a dielectric multilayer film made of alternately stacked SiO ２ layer and Nb ２ O ５ The dielectric multilayer film may include, for example, a Nb layer having a thickness of 10 nm or more and 100 nm or less. ２ O ５ layer and a SiO layer having a thickness of 10 nm or more and 100 nm or less. ２ The number of pairs of layers can be from 2 to 6. By setting the thickness and number of layers of each layer of the dielectric multilayer film in this way, good light reflectivity can be achieved.

[0020] 2, the first electrode 31 is disposed on the first insulating film 20. The first electrode 31 is not connected to the second surface 10a of the semiconductor structure 10. The first insulating film 20 is located between the first electrode 31 and the second surface 10a. As shown in FIG. 1B, the first electrode 31 has a first portion 31a located outside the outer edge 10d of the semiconductor structure 10 in a plan view. As will be described later, the first electrode 31 is electrically connected to the first semiconductor layer 11 via a first wiring 61.

[0021] The first electrode 31 may be, for example, a single metal layer containing Ti, Rh, Au, Pt, Al, Ag, Rh, or Ru, or may have a laminated structure containing at least two of these metal layers.

[0022] <Second Electrode> The second electrode 32 is disposed on the first insulating film 20. As shown in FIG. 1B , the second electrode 32 is separated from the first electrode 31. As shown in FIG. 2 , a portion of the second electrode 32 is disposed in the first opening 20 a of the first insulating film 20. The second electrode 32 is electrically connected to the second semiconductor layer 13 at the first opening 20 a on the second surface 10 a of the semiconductor structure 10. FIG. 2 shows an example in which the second electrode 32 is electrically connected to the second semiconductor layer 13 via a conductive layer 41, which will be described later. Alternatively, the second electrode 32 may be electrically connected to the second semiconductor layer 13 by directly contacting the second semiconductor layer 13 at the first opening 20 a.

[0023] The second electrode 32 can be a single metal layer made of the same material as the first electrode 31, or a laminated structure including at least two of these metal layers.

[0024] <Second Insulating Film> The second insulating film 52 is disposed on the first surface 10b and the side surface 10c of the semiconductor structure 10. The second insulating film 52 covers the first surface 10b and the side surface 10c. The second insulating film 52 is also disposed on a portion of the first insulating film 20 that is located outside the outer edge 10d of the semiconductor structure 10 in a planar view. The transmittance of the second insulating film 52 for the peak wavelength of light emitted by the active layer 12 is, for example, 60% or more, preferably 70% or more. The second insulating film 52 can be, for example, a silicon oxide film or a silicon nitride film.

[0025] The second insulating film 52 has a third opening 52a located above the first surface 10b of the semiconductor structure 10. The third opening 52a may be located above the side surface 10c of the semiconductor structure 10. The second insulating film 52 also has a fourth opening 52b located above the second opening 20b of the first insulating film 20.

[0026] <First wiring> The first wiring 61 is arranged on the second insulating film 52, and electrically connects a part of the first semiconductor layer 11 exposed from the second insulating film 52 in the third opening 52 a to the first part 31 a of the first electrode 31 exposed from the first insulating film 20 in the second opening 20 b.

[0027] The first wiring 61 is disposed in the third opening 52a of the second insulating film 52 and has a first connection portion 61a electrically connected to the first semiconductor layer 11 on the first surface 10b. When the third opening 52a is located above the side surface 10c of the semiconductor structure 10, the first wiring 61 is electrically connected to the first semiconductor layer 11 on the side surface 10c. The first wiring 61 is disposed in the second opening 20b of the first insulating film 20 and has a second connection portion 61b electrically connected to the first portion 31a of the first electrode 31. The first wiring 61 also has an intermediate portion 61c that connects the first connection portion 61a and the second connection portion 61b and is located on the second insulating film 52 covering the side surface 10c of the semiconductor structure 10. The lower end of the intermediate portion 61c is disposed in the fourth opening 52b of the second insulating film 52 and is connected to the second connection portion 61b. The intermediate portion 61c is in contact with the second insulating film 52. The first wiring 61 is made of a transparent conductive film or a metal film.

[0028] The light-emitting element 1 can be disposed on a wiring substrate with the second surface 10a of the semiconductor structure 10 facing the wiring substrate. The first electrode 31 and the second electrode 32 disposed on the second surface 10a can be electrically connected to conductive portions of the wiring substrate via a connecting member such as solder. The second electrode 32 is electrically connected to the second semiconductor layer 13 on the second surface 10a side through the first opening 20a of the first insulating film 20. In contrast, the first electrode 31 is not electrically connected to the first semiconductor layer 11 on the second surface 10a side, but is electrically connected to the first semiconductor layer 11 on the first surface 10b side via the first wiring 61. Therefore, the semiconductor structure 10 is electrically connected to the first electrode 31 and the second electrode 32 without removing the active layer 12, thereby ensuring a large area for the active layer 12 in a planar view and improving the brightness of the light-emitting element 1.

[0029] As a reference example of a configuration for electrically connecting the first semiconductor layer 11 to the conductive portion of the wiring substrate, a configuration in which the first surface 10b and the conductive portion of the wiring substrate are connected by wires can be considered. According to this embodiment, the first semiconductor layer 11 is electrically connected to the conductive portion of the wiring substrate via a first wiring 61 arranged on the second insulating film 52 covering the side surface 10c of the semiconductor structure 10 and a first electrode 31 arranged on the second surface 10a side. This configuration of this embodiment can reduce the area required for arranging and connecting the light-emitting element to the wiring substrate compared to the reference example. This enables the miniaturization of a light-emitting device including the light-emitting element and the wiring substrate. It also makes it easier to arrange multiple light-emitting elements on the wiring substrate with high density.

[0030] As described above, light emitted by the active layer 12 is emitted from the first surface 10b and the side surface 10c of the semiconductor structure 10. Therefore, as shown in Fig. 1A, in a plan view, the width of the first wiring 61 in the second direction Y is preferably smaller than the width of the first surface 10b in the second direction Y and the width of the side surface 10c in the second direction Y. This reduces absorption of light emitted by the active layer 12 in the first wiring 61, and can improve the brightness of the light-emitting element 1.

[0031] The area of ​​the first connection portion 61a in a plan view is preferably 1% to 20% of the area of ​​the first surface 10b. Having such an area for the first connection portion 61a reduces absorption of light emitted from the active layer 12 by the first wiring 61. Furthermore, the width of the intermediate portion 61c in the second direction Y is preferably smaller than the width of the first connection portion 61a in the second direction Y. This reduces absorption of light emitted from the active layer 12 by the intermediate portion 61c. When the width of the intermediate portion 61c in the second direction Y is smaller than the width of the first connection portion 61a in the second direction Y, for example, the width of the intermediate portion 61c in the second direction Y is 5% to 50% of the width of the first connection portion 61a in the second direction Y. Furthermore, the first wiring 61 is preferably made of a translucent conductive film. This reduces absorption of light emitted from the active layer 12 by the first wiring 61, thereby improving the brightness of the light-emitting element 1. Examples of materials for the transparent conductive film of the first wiring 61 include ITO (Indium Tin Oxide), ZnO (Zinc Oxide), and In ２ O ３ (Indium Oxide), etc. can be used. The transmittance of the transparent conductive film with respect to the peak wavelength of light emitted by the active layer 12 is, for example, 60% or more, preferably 70% or more. Furthermore, a transparent conductive film made of these materials can reduce the contact resistance with the semiconductor structure 10 on the first surface 10b compared to when a metal film is used.

[0032] When the first semiconductor layer 11 and the first electrode 31 are connected on the second surface 10a side, the ratio of the area of ​​the first semiconductor layer 11 exposed from the second semiconductor layer 13 and the active layer 12 to the total area of ​​the second surface 10a in plan view tends to increase as the size of the light-emitting element 1 decreases. Therefore, the configuration of this embodiment in which the active layer 12 is not removed is highly effective in ensuring a large area in plan view for the active layer 12, and it is easy to improve brightness, for example, when the length of one side in plan view of the light-emitting element 1 is 100 μm or less.

[0033] As shown in FIG. 1B , the first electrode 31 further includes a second portion 31b located inside the outer edge 10d of the semiconductor structure 10 in a planar view. The second portion 31b and the first portion 31a can be integrally formed using the same material. Having the second portion 31b located inside the outer edge 10d of the semiconductor structure 10 in a planar view allows the area of ​​the first electrode 31 to be increased while reducing the size of the light-emitting element 1 in a planar view. Increasing the area of ​​the first electrode 31 in a planar view increases the contact area between the first electrode 31 and the conductive portion of the wiring substrate, thereby reducing the forward voltage of the light-emitting element 1. Furthermore, heat generated by the semiconductor structure 10 can be more easily dissipated to the wiring substrate via the second portion 31b. The second portion 31b overlaps the second surface 10a of the semiconductor structure 10 in a planar view.

[0034] In a plan view, the area of ​​the first electrode 31 having the first portion 31 a and the second portion 31 b can be, for example, 80% to 120% of the area of ​​the second electrode 32. This reduces the difference between the area of ​​the first electrode 31 and the area of ​​the second electrode 32 in a plan view, and reduces misalignment that occurs when the light-emitting element 1 is disposed on a wiring board via a connecting member such as solder.

[0035] In a plan view, the area of ​​the first portion 31a located outside the outer edge 10d of the semiconductor structure 10 is preferably smaller than the area of ​​the second portion 31b. This allows the size of the light-emitting element 1 to be reduced. Furthermore, in a plan view, the area of ​​the second portion 31b is larger than the area of ​​the first portion 31a, which allows the ease of placement of the light-emitting element 1 on a wiring substrate, the effect of reducing forward voltage, and the heat dissipation effect to be improved. In a plan view, the area of ​​the first portion 31a is, for example, 5% to 20% of the area of ​​the second portion 31b.

[0036] In a plan view, the sum of the area of ​​the second portion 31b and the area of ​​the second electrode 32 is preferably 60% to 90% of the area of ​​the second surface 10a. By setting this value, light from the active layer 12 that is directed toward the second surface 10a can be easily reflected by the second portion 31b and the second electrode 32, thereby improving the light extraction efficiency.

[0037] 2 , the light-emitting element 1 may further include a conductive layer 41 disposed on the second surface 10 a of the semiconductor structure 10. The conductive layer 41 is electrically connected to the second semiconductor layer 13 on the second surface 10 a. The conductive layer 41 is covered with the first insulating film 20. A portion of the conductive layer 41 is exposed from the first insulating film 20 in the first opening 20 a and is electrically connected to the second electrode 32.

[0038] 1B , in a plan view, an outer edge 41 a of the conductive layer 41 is located inside an outer edge 10 d of the semiconductor structure 10. In a plan view, the area of ​​the conductive layer 41 is larger than the area of ​​the first opening 20 a. Compared to a case where the second electrode 32 is directly connected to the second surface 10 a through the first opening 20 a, the conductive layer 41 makes it easier to diffuse the current supplied through the second electrode 32 in the surface direction of the second semiconductor layer 13.

[0039] The conductive layer 41 may be made of, for example, a transparent conductive film. Examples of the transparent conductive film include ITO, ZnO, and In. ２ O ３ Examples of suitable transparent conductive films include those described above. By using these materials, the contact resistance between the conductive layer 41 and the second surface 10a can be reduced compared to when a metal material is used, thereby reducing the forward voltage of the light-emitting element 1. Furthermore, a metal material may be used as the material for the conductive layer 41. Examples of metal materials for the conductive layer 41 include materials similar to those used for the first electrode 31. By using these materials, light from the active layer 12 can be more easily reflected compared to when a transparent conductive film is used, thereby improving the light extraction efficiency of the light-emitting element 1.

[0040] <Third Insulating Film> The light-emitting element 1 can further include a third insulating film 53. The third insulating film 53 covers the first wiring 61. As the third insulating film 53, for example, a silicon oxide film or a silicon nitride film can be used.

[0041] 3 to 17, a method for manufacturing a light-emitting element according to the first embodiment will be described. The method for manufacturing a light-emitting element according to the first embodiment includes the steps of preparing a wafer, bonding the wafer to a second substrate, exposing an upper surface of the first semiconductor layer, separating the semiconductor structure into a plurality of light-emitting portions, forming a second insulating film, exposing a first portion of the first electrode from the first insulating film and exposing a portion of the first semiconductor layer from the second insulating film, forming first wiring, and separating the light-emitting portions from the second substrate.

[0042] 6 shows a portion of a wafer W. The wafer W has a first substrate 101, a semiconductor structure 10, a first insulating film 20, a first electrode 31, and a second electrode 32.

[0043] The first substrate 101 may be, for example, sapphire or spinel (MgAl) having a C-plane, an R-plane, or an A-plane as a principal surface. ２ O ４ ) can be used. Alternatively, a conductive substrate such as SiC (including 6H, 4H, and 3C), ZnS, ZnO, GaAs, or Si may be used as the first substrate 101. In this embodiment, a sapphire substrate having a C-plane as its principal surface is used as the first substrate 101. The semiconductor structure 10 is disposed on the principal surface of the first substrate 101. The semiconductor structure 10 has a first semiconductor layer 11, a second semiconductor layer 13 that is farther from the first substrate 101 than the first semiconductor layer 11, and an active layer 12 that is located between the first semiconductor layer 11 and the second semiconductor layer 13.

[0044] The surface of the first semiconductor layer 11 facing the active layer 12 does not have a portion exposed from the second semiconductor layer 13 and the active layer 12. This allows the area of ​​the active layer 12 to be increased in plan view, as described above.

[0045] Furthermore, it is preferable that a portion of the first semiconductor layer 11 is not exposed from the second semiconductor layer 13 and the active layer 12 on the upper surface side of the semiconductor structure 10 where the second semiconductor layer 13 is located. This allows the metal contained in the first electrode 31 or the second electrode 32 to be ionized in the liquid when a treatment using a liquid such as wet etching is performed in a subsequent step, thereby reducing the occurrence of metal migration due to the potential difference between a portion (exposed portion) of the first semiconductor layer 11 and the second semiconductor layer 13. This makes it difficult for metal to deposit in unintended areas, thereby improving the reliability of the light-emitting device.

[0046] The first insulating film 20 is disposed on the second semiconductor layer 13 and has a first opening 20a located above the second semiconductor layer 13. The first electrode 31 is disposed on the first insulating film 20. The second electrode 32 is disposed on the first insulating film 20 at a distance from the first electrode 31 and is electrically connected to the second semiconductor layer 13 through the first opening 20a. The wafer W may further include a conductive layer 41 disposed on the second semiconductor layer 13 and electrically connected to the second electrode 32.

[0047] In the step of preparing the wafer W, the wafer W shown in FIG. 6 can be purchased and prepared.

[0048] The process of preparing the wafer W may include the processes shown in Figures 3 to 6. Each of the processes shown in Figures 3 to 6 will be described below.

[0049] 3, a semiconductor structure 10 is formed on a first substrate 101. For example, by MOCVD (Metal Organic Chemical Vapor Deposition), a first semiconductor layer 11, an active layer 12, and a second semiconductor layer 13 are sequentially formed on the first substrate 101 to form the semiconductor structure 10. In this embodiment, after the semiconductor structure 10 is formed on the first substrate 101, a step of removing a part of the second semiconductor layer 13 and a part of the active layer 12 to expose a part of the first semiconductor layer 11 from the second semiconductor layer 13 and the active layer 12 is not performed.

[0050] The step of preparing the wafer W may include a step of forming a conductive layer 41 on the second semiconductor layer 13, as shown in FIG. 4 . The conductive layer 41 contacts the upper surface of the second semiconductor layer 13 and is electrically connected to the second semiconductor layer 13. The conductive layer 41 may be formed by, for example, a sputtering method or a vapor deposition method. The conductive layer 41 does not necessarily have to be formed. In the following description, a case where the conductive layer 41 is formed will be described.

[0051] 5, the step of preparing the wafer W includes a step of forming a first insulating film 20 having a first opening 20a located above the conductive layer 41 on the second semiconductor layer 13 and the conductive layer 41. A portion of the conductive layer 41 is exposed from the first insulating film 20 in the first opening 20a. The first insulating film 20 can be formed by, for example, a chemical vapor deposition (CVD) method or a sputtering method. The first opening 20a can be formed by, for example, removing a portion of the first insulating film 20 by etching.

[0052] As shown in FIG. 6 , the process of preparing the wafer W includes a process of forming a first electrode 31 and a second electrode 32. The second electrode 32 is formed on the first insulating film 20 and in the first opening 20 a, and is electrically connected to the conductive layer 41 in the first opening 20 a. The second electrode 32 is electrically connected to the second semiconductor layer 13 via the conductive layer 41. The first electrode 31 is formed on the first insulating film 20, spaced apart from the second electrode 32. In the process shown in FIG. 6 , the first electrode 31 is not electrically connected to the first semiconductor layer 11. The first electrode 31 and the second electrode 32 can be formed by, for example, a sputtering method or a vapor deposition method. The first electrode 31 and the second electrode 32 can be formed simultaneously using the same material.

[0053] 7, the side of the wafer W on which the second electrode 32 and the first electrode 31 are arranged is bonded to the second substrate 102 via a bonding member 51. The top and bottom positions of the wafer W shown in FIG. 7 are reversed to the top and bottom positions of the wafer W shown in FIG.

[0054] The bonding member 51 is disposed between the first insulating film 20 and the second substrate 102. The bonding member 51 covers the first electrode 31 and the second electrode 32. For example, a resin member mainly composed of epoxy resin, acrylic resin, or polyimide resin can be used as the bonding member 51. For example, a substrate similar to the first substrate 101 can be used as the second substrate 102.

[0055] <Step of Exposing the Top Surface of the First Semiconductor Layer> After the step of bonding the wafer W and the second substrate 102, the first substrate 101 is removed to expose the top surface 11a of the first semiconductor layer 11, as shown in Fig. 8. The first substrate 101 can be removed by, for example, a laser lift-off (LLO) method, grinding, polishing, etching, or the like.

[0056] <Step of Separating Semiconductor Structure into Multiple Light Emitting Portions> After removing the first substrate 101, a portion of the semiconductor structure 10 is removed from the exposed upper surface 11a side of the first semiconductor layer 11, and the semiconductor structure 10 is separated into multiple light emitting portions 100, as shown in Figures 9 and 10. Figure 9 is a schematic cross-sectional view taken along line IX-IX in Figure 10.

[0057] 10 , in the step of separating the semiconductor structure 10 into the plurality of light emitting portions 100, the semiconductor structure 10 is separated into the plurality of light emitting portions 100 so that the first electrode 31 has a first portion 31a located outside the outer edge 100d of the light emitting portion 100 in a plan view. In other words, the semiconductor structure 10 that overlaps a part of the first electrode 31 (a portion that will become the first portion 31a) in a plan view is removed.

[0058] In the process of separating the semiconductor structure 10 into the plurality of light emitting portions 100, a portion of the semiconductor structure 10 is removed, thereby exposing the upper surface of the first insulating film 20 from the semiconductor structure 10 (light emitting portion 100). By removing the portion of the semiconductor structure 10, grooves extending in the first direction X and the second direction Y are formed on the first insulating film 20, and the semiconductor structure 10 is separated into the plurality of light emitting portions 100 aligned in the first direction X and the second direction Y.

[0059] A portion of the semiconductor structure 10 can be removed by dry etching using a mask. Examples of dry etching include RIE (Reactive Ion Etching). In the RIE method, for example, Cl ２ , SiCl ４ A chlorine-containing gas such as chlorine-containing fluorine-containing fluorine or the like can be used. Compared to wet etching, dry etching makes it easier to control the amount of etching, so the light emitting portion 100 can be formed into a desired shape by removing a portion of the semiconductor structure 10 by dry etching. Alternatively, a portion of the semiconductor structure 10 can be removed by wet etching using a mask.

[0060] The light emitting unit 100 has an upper surface 100a, a lower surface 100c located on the opposite side of the upper surface 100a in the third direction Z, and a side surface 100b connecting the upper surface 100a and the lower surface 100c. The upper surface 100a of the light emitting unit 100 is the upper surface 11a of the first semiconductor layer 11. The lower surface 100c of the light emitting unit 100 is the lower surface of the second semiconductor layer 13. The side surface 100b of the light emitting unit 100 corresponds to the side surface 10c of the semiconductor structure 10 shown in FIG. 2. The area of ​​the lower surface 100c of the light emitting unit 100 is larger than the area of ​​the upper surface 100a of the light emitting unit 100. The side surface 100b of the light emitting unit 100 includes the side surface of the first semiconductor layer 11, the side surface of the active layer 12, and the side surface of the second semiconductor layer 13.

[0061] As shown in FIG. 9 , the cross-sectional shape of the light-emitting section 100 can be approximately trapezoidal. The active layer 12 is located closer to the lower surface 100c of the light-emitting section 100 than to the upper surface 100a. The area of ​​the lower surface 100c of the light-emitting section 100 is larger than the area of ​​the upper surface 100a of the light-emitting section 100. Therefore, the light-emitting section 100 can have a larger area of ​​the active layer 12 than when the area of ​​the upper surface 100a is larger than the area of ​​the lower surface 100c. The side surface 100b is inclined with respect to the upper surface 100a. The angle between the side surface 100b and the lower surface 100c is an acute angle, and the angle between the side surface 100b and the upper surface 100a is an obtuse angle.

[0062] <Step of Forming Second Insulating Film> After the step of separating the semiconductor structure 10 into a plurality of light emitting portions 100, a second insulating film 52 covering the light emitting portions 100 is formed, as shown in FIG. 11 . The second insulating film 52 covers the upper surface 100a and the side surface 100b of the light emitting portion 100. The second insulating film 52 also covers the upper surface of the first insulating film 20 exposed from the light emitting portion 100. Note that the second insulating film 52 does not necessarily have to cover the upper surface of the first insulating film 20. The second insulating film 52 can be formed by, for example, a CVD method or a sputtering method.

[0063] <Process of exposing the first portion of the first electrode from the first insulating film and exposing a portion of the first semiconductor layer from the second insulating film> After the process of forming the second insulating film 52, as shown in FIG. 12 , a portion of the first insulating film 20 is removed to expose the first portion 31 a of the first electrode 31 from the first insulating film 20, and a portion of the second insulating film 52 is removed to expose a portion of the first semiconductor layer 11 of the light emitting section 100 from the second insulating film 52.

[0064] For example, by RIE using a mask, it is possible to remove a part of the first insulating film 20 and a part of the second insulating film 52. As a gas for RIE, for example, a gas containing fluorine can be used.

[0065] A third opening 52a is formed in the second insulating film 52 by removing a portion of the second insulating film 52 covering the upper surface 11a of the first semiconductor layer 11, which is the upper surface 100a of the light emitting unit 100. In the third opening 52a, a portion of the upper surface 11a of the first semiconductor layer 11 is exposed from the second insulating film 52. The third opening 52a may be formed in the second insulating film 52 at a position where the side surface 10c is exposed.

[0066] A second opening 20b is formed in the first insulating film 20 by removing a part of the first insulating film 20 located above the first portion 31a of the first electrode 31. The first portion 31a of the first electrode 31 is exposed from the first insulating film 20 in the second opening 20b.

[0067] When the second insulating film 52 covers the upper surface of the first insulating film 20, a fourth opening 52b is formed in the second insulating film 52 by removing a portion of the second insulating film 52 located above the first portion 31a of the first electrode 31 before forming the second opening 20b in the first insulating film 20. After forming the fourth opening 52b in the second insulating film 52, a portion of the first insulating film 20 exposed from the second insulating film 52 in the fourth opening 52b is removed to form the second opening 20b below the fourth opening 52b. The first portion 31a of the first electrode 31 is exposed from the first insulating film 20 and the second insulating film 52 in the second opening 20b and the fourth opening 52b.

[0068] <Step of Forming First Wiring> After the step of exposing the first portion 31 a of the first electrode 31 from the first insulating film 20 and exposing a part of the first semiconductor layer 11 from the second insulating film 52, the first wiring 61 is formed on the second insulating film 52 as shown in Fig. 13. For example, the first wiring 61 can be formed by sputtering or vapor deposition.

[0069] The first wiring 61 electrically connects a portion of the first semiconductor layer 11 exposed from the second insulating film 52 to the first portion 31a of the first electrode 31 exposed from the first insulating film 20. This allows the first electrode 31 arranged on the lower surface 100c side of the light emitting section 100 to be electrically connected to the first semiconductor layer 11 on the upper surface 11a side of the first semiconductor layer 11, even if a portion of the first semiconductor layer 11 on the lower surface 100c side of the light emitting section 100 is not exposed from the second semiconductor layer 13 and the active layer 12.

[0070] In a third opening 52a formed in the second insulating film 52, a first connection portion 61a of the first wiring 61 is electrically connected to the upper surface 11a of the first semiconductor layer 11. When the third opening 52a is located above the side surface 10c of the semiconductor structure 10, the first wiring 61 is electrically connected to the first semiconductor layer 11 at the side surface 10c. In a second opening 20b formed in the first insulating film 20, a second connection portion 61b of the first wiring 61 is electrically connected to the first portion 31a of the first electrode 31. An intermediate portion 61c of the first wiring 61, which connects the first connection portion 61a and the second connection portion 61b, is formed on the second insulating film 52 covering the side surface 100b of the light emitting unit 100. The intermediate portion 61c is in contact with the second insulating film 52.

[0071] <Step of Forming Third Insulating Film> After forming the first wiring 61, the method for manufacturing the light-emitting element according to the first embodiment may include a step of forming a third insulating film 53 that covers the first wiring 61, as shown in Fig. 14. The third insulating film 53 can be formed by, for example, a CVD method or a sputtering method.

[0072] <Step of Separating the Light-Emitting Section and the Second Substrate> After the first wiring 61 is formed, the light-emitting section 100 is separated from the second substrate 102. The step of separating the light-emitting section 100 from the second substrate 102 can include the steps shown in FIGS.

[0073] After the first wiring 61 is formed, the first insulating film 20 located in the region between the light-emitting units 100 in a plan view is removed to form a first groove 71 shown in FIG. 15 in the first insulating film 20. In the first groove 71, the upper surface of the bonding member 51 is exposed from the second insulating film 52 and the first insulating film 20. If the second insulating film 52 is also disposed in the region between the light-emitting units 100 in a plan view, the first insulating film 20 is removed after the second insulating film 52 is removed. The second insulating film 52 can be removed using a method similar to that used to remove the first insulating film 20.

[0074] 16 , after the first groove 71 is formed, the bonding member 51 below the first groove 71 is removed, and a second groove 72 is formed below the first groove 71. A plurality of light-emitting elements 1 separated from one another on the second substrate 102 by the first groove 71 and the second groove 72 are obtained. Each light-emitting element 1 has a light-emitting portion 100, a first electrode 31, a second electrode 32, a first insulating film 20, a second insulating film 52, and a first wiring 61. The light-emitting element 1 may also have a conductive layer 41 and a third insulating film 53, as necessary.

[0075] The first groove 71 and the second groove 72 can be formed by, for example, RIE. After the first groove 71 is formed by RIE, the gas can be switched and the second groove 72 can be formed by RIE. The first groove 71 can be formed by, for example, RIE using a gas containing fluorine. The second groove 72 can be formed by, for example, RIE using a gas containing oxygen. The first groove 71 and the second groove 72 may be formed consecutively by RIE using the same gas.

[0076] The light-emitting element 1 is supported on the second substrate 102 via a bonding member 51. For example, the light-emitting element 1 can be separated from the second substrate 102 by irradiating the second substrate 102 with laser light to remove the bonding member 51. As shown in FIG. 17 , the upper surface 100a of the light-emitting portion 100 of the light-emitting element 1 separated from the second substrate 102 is adhered to, for example, an adhesive support member 103. The light-emitting element 1 may be separated from the second substrate 102 after being adhered to the support member 103. If the bonding member 51 remains on the first electrode 31 and the second electrode 32 after the light-emitting element 1 is separated from the second substrate 102, the bonding member 51 may be removed by, for example, RIE to expose the first electrode 31 and the second electrode 32. The first electrode 31 and the second electrode 32 function as external connection terminals to be bonded to conductive portions of the wiring substrate.

[0077] 10 , in the process of separating the semiconductor structure 10 into the plurality of light emitting portions 100, the semiconductor structure 10 can be separated into the plurality of light emitting portions 100 so that the first electrode 31 has a second portion 31b located inside the outer edge 100d of the light emitting portion 100 in a plan view. This allows the area of ​​the first electrode 31 to be increased while reducing the size of the light emitting element. By increasing the area of ​​the first electrode 31, as described above, when the light emitting element is disposed on a wiring substrate, the forward voltage can be reduced and the heat dissipation effect can be improved.

[0078] In a plan view, the area of ​​the first portion 31 a is preferably smaller than the area of ​​the second portion 31 b, which allows the size of the light-emitting element to be reduced. Furthermore, in a plan view, the area of ​​the second portion 31 b is larger than the area of ​​the first portion 31 a, which allows the light-emitting element to be easily arranged on a wiring substrate, and improves the effect of reducing forward voltage and the heat dissipation effect, as described above.

[0079] In addition, in the step of forming the first wiring 61, it is preferable to form the first wiring 61 from a light-transmitting conductive film, so that absorption of light emitted from the active layer 12 in the first wiring 61 can be reduced.

[0080] Second Embodiment FIG. 18 is a schematic cross-sectional view of a light-emitting element 2 according to a second embodiment.

[0081] In the light-emitting element 2 according to the second embodiment, the first surface 10b of the semiconductor structure 10 includes a plurality of protrusions 10b1, and the side surface 10c of the semiconductor structure 10 includes a plurality of protrusions 10c1, thereby improving the light extraction efficiency from the first surface 10b and the side surface 10c.

[0082] The arithmetic mean height of the first surface 10b including the plurality of convex portions 10b1 can be made greater than the arithmetic mean height of the side surface 10c including the plurality of convex portions 10c1, which makes it easier for light to be extracted from the first surface 10b than from the side surface 10c, thereby achieving a light distribution characteristic with high directivity in the direction directly above the first surface 10b.

[0083] Furthermore, a convex portion shaped to conform to the convex portion 10b1 is formed on the surface of the second insulating film 52 covering the first surface 10b, and a convex portion shaped to conform to the convex portion 10c1 of the side surface 10c is formed on the surface of the second insulating film 52 covering the side surface 10c. This can improve the extraction efficiency of light extracted from the first surface 10b and the side surface 10c via the second insulating film 52. Furthermore, a convex portion shaped to conform to the convex portion 10c1 is formed on the surface of the first wiring 61 arranged on the second insulating film 52 covering the side surface 10c and on the surface of the third insulating film 53 covering the first wiring 61. This can improve the extraction efficiency of light extracted from the side surface 10c via the first wiring 61 and the third insulating film 53.

[0084] A first method for forming a plurality of protrusions on the first surface 10b and the side surface 10c of the semiconductor structure 10 in the light-emitting element 2 will be described with reference to FIGS. 8, 19 and 20. FIG.

[0085] In the first method, after the step of exposing the upper surface 11a of the first semiconductor layer 11 shown in FIG. 8, the upper surface 11a of the first semiconductor layer 11 is roughened before the semiconductor structure 10 is separated into a plurality of light emitting portions 100 as shown in FIG. ２ , SiCl ４ The upper surface 11a of the first semiconductor layer 11 can be roughened by dry etching using a chlorine-containing gas such as HCl or wet etching using an alkaline solution such as TMAH (Tetramethylammonium hydroxide).

[0086] After roughening the upper surface 11a of the first semiconductor layer 11, as shown in FIG. 20 , a portion of the semiconductor structure 10 is removed to separate the semiconductor structure 10 into a plurality of light emitting portions 100. For example, a mask placed on the upper surface 11a of the first semiconductor layer 11 is used to remove a portion of the semiconductor structure 10 by dry etching. For example, the dry etching method may be an RIE method. In the RIE method, for example, Cl ２ , SiCl ４ It is possible to use a gas containing chlorine such as: Dry etching has good etching controllability, and it is easy to shape the light emitting section 100 into a desired shape after etching.

[0087] In the process of removing a portion of the semiconductor structure 10 to separate it into light-emitting portions 100, dry etching proceeds from the roughened upper surface 11a of the first semiconductor layer 11 exposed by the mask. Therefore, the surface roughness of the dry-etched surface of the semiconductor structure 10 is greater than when the upper surface 11a is not previously roughened. Therefore, as shown in FIG. 20 , the side surface 100b of the light-emitting portion 100 exposed by removing a portion of the semiconductor structure 10 can be roughened. This allows the process of separating the semiconductor structure 10 into multiple light-emitting portions 100 and the roughening of the side surface 100b of the light-emitting portion 100 to be performed in a single process, thereby efficiently manufacturing light-emitting devices with improved light extraction efficiency. The side surface 100b of the light-emitting portion 100 exposed by removing a portion of the semiconductor structure 10 shown in FIG. 20 corresponds to the side surface 10c of the semiconductor structure 10 in the light-emitting element 2 shown in FIG. 18 .

[0088] Alternatively, a portion of the semiconductor structure 10 may be removed by wet etching to separate it into the light emitting portion 100. Compared to dry etching, wet etching makes it easier to increase the surface roughness of the side surface 10c and improve the light extraction efficiency from the side surface 10c.

[0089] A second method for forming a plurality of protrusions on the first surface 10b and the side surface 10c of the semiconductor structure 10 in the light-emitting element 2 will be described with reference to FIGS.

[0090] According to the second method, after the step of separating the semiconductor structure 10 shown in FIG. 9 into a plurality of light emitting portions 100, the upper surface 100a and the side surface 100b of the light emitting portion 100 are roughened as shown in FIG.

[0091] For example, the top surface 100a and the side surface 100b of the light emitting portion 100 are roughened by dry etching using a chlorine-containing gas or wet etching using an alkaline solution such as TMAH. According to the second method, the top surface 100a and the side surface 100b of the light emitting portion 100 can be roughened in a single process, making it possible to efficiently manufacture a light emitting device with improved light extraction efficiency. The top surface 100a and the side surface 100b of the light emitting portion 100 in Fig. 20 correspond to the first surface 10b and the side surface 10c, respectively, of the semiconductor structure 10 in the light emitting device 2 shown in Fig. 18.

[0092] According to the second method, a portion of the semiconductor structure 10 is removed while the upper surface 11a of the first semiconductor layer 11 is not roughened, and the semiconductor structure 10 is separated into a plurality of light emitting sections 100. According to the second method, the upper surface 11a of the first semiconductor layer 11, which becomes the first surface 100a of the light emitting section 100, is etched while having a high degree of flatness, compared to the first method, and therefore it is easier to form the light emitting section 100 into a desired shape.

[0093] Furthermore, when the semiconductor structure 10 is grown on the C-plane of a sapphire substrate as the first substrate 101, the crystal orientation of the top surface 100a of the light emitting portion 100 is different from that of the side surface 100b of the light emitting portion 100. Therefore, by performing a roughening process on the top surface 100a and the side surface 100b of the light emitting portion 100 after separation into the light emitting portions 100, the surface roughness of the top surface 100a of the light emitting portion 100 can be made greater than the surface roughness of the side surface 100b of the light emitting portion 100. This makes it easier for light to be extracted from the first surface 10b than from the side surface 10c of the semiconductor structure 10 in the light emitting element 2, and light distribution characteristics with high directivity in the direction directly above the first surface 10b can be obtained.

[0094] Third Embodiment Fig. 21A is a schematic bottom view of a light-emitting element 3 according to a third embodiment. Fig. 21B is a schematic cross-sectional view taken along line XXIB-XXIB in Fig. 21A.

[0095] The light-emitting element 3 according to the third embodiment further includes a reflective film 42 disposed between the second semiconductor layer 13 and the second electrode 32. The reflective film 42 is reflective to light emitted by the active layer 12. The reflective film 42 may be made of, for example, a metal. The reflective film 42 may include, for example, an Al film, a Ti film, or a laminated structure thereof. Light traveling from the active layer 12 toward the second surface 10a of the semiconductor structure 10 can be reflected by the reflective film 42 and directed toward the first surface 10b and the side surface 10c. This improves the brightness of the light-emitting element 3. The reflectivity of the reflective film 42 with respect to the peak wavelength of light emitted by the active layer 12 is, for example, 60% or more, preferably 70% or more.

[0096] The reflective film 42 can be disposed, for example, between the conductive layer 41 and the second portion 31 b. The first insulating film 20 is located between the reflective film 42 and the conductive layer 41, between the reflective film 42 and the second electrode 32, and between the reflective film 42 and the second portion 31 b of the first electrode 31.

[0097] 21A , in a plan view, an outer edge 42 a of the reflective film 42 can be located, for example, more inward than an outer edge 41 a of the conductive layer 41. In a plan view, the reflective film 42 does not overlap a portion where the second electrode 32 is connected to the conductive layer 41 in the first opening 20 a of the first insulating film 20.

[0098] In a plan view, the reflective film 42 is preferably disposed in a position overlapping the region between the first electrode 31 and the second electrode 32. By disposing the reflective film 42 in this manner, light from the active layer 12 traveling toward the second surface 10a can be reflected toward the first surface 10b in the region between the first electrode 31 and the second electrode 32, thereby improving the light extraction efficiency of the light-emitting element 3. Furthermore, in a plan view, the area of ​​the reflective film 42 can be set to 60% to 90% of the area of ​​the second surface 10a. This improves the light extraction efficiency of the light-emitting element 3.

[0099] The process of preparing a wafer in the method for manufacturing the light emitting element 3 according to the third embodiment can include the steps shown in FIGS.

[0100] As shown in FIG. 22 , the first layer 21 of the first insulating film 20 is formed on the upper surface of the second semiconductor layer 13 on the conductive layer 41 arranged on the upper surface of the second semiconductor layer 13 .

[0101] After the first layer 21 is formed, as shown in Fig. 23, a reflective film 42 is formed on the first layer 21. The reflective film 42 can be formed by, for example, sputtering or vapor deposition.

[0102] 24 , the second layer 22 of the first insulating film 20 is formed on the first layer 21 so as to cover the reflective film 42. After the second layer 22 is formed, a first opening 20a is formed in the first insulating film 20. The first opening 20a is formed above the conductive layer 41 in a portion where the reflective film 42 is not disposed.

[0103] 25, after the first opening 20a is formed, a second electrode 32 is formed in the first opening 20a and on the second layer 22. In addition, a first electrode 31 is formed on the second layer 22.

[0104] The structure of the light-emitting element 2 of the second embodiment and the structure of the light-emitting element 3 of the third embodiment can be combined to form a light-emitting element having a semiconductor structure 10 including a roughened first surface 10b and side surface 10c, and a reflective film 42.

[0105] Embodiments of the present invention include the following light-emitting device and method for manufacturing the same.

[0106] [Item 1] A process of preparing a wafer including: a first substrate; a semiconductor structure disposed on the first substrate, the semiconductor structure having a first semiconductor layer, a second semiconductor layer disposed farther from the first substrate than the first semiconductor layer, and an active layer disposed between the first semiconductor layer and the second semiconductor layer; a first insulating film disposed on the second semiconductor layer and having an opening located above the second semiconductor layer; a first electrode disposed on the first insulating film; and a second electrode disposed on the first insulating film and spaced apart from the first electrode, the second electrode electrically connecting to the second semiconductor layer through the opening; a process of bonding the side of the wafer on which the second electrode and the first electrode are disposed to a second substrate; after the process of bonding the wafer to the second substrate, removing the first substrate to expose an upper surface of the first semiconductor layer; and a process of removing a portion of the semiconductor structure from the upper surface side of the first semiconductor layer and separating the semiconductor structure into a plurality of light emitting sections, the process of separating the semiconductor structure into a plurality of light emitting sections such that the first electrode has a first portion located outside an outer edge of the light emitting section in a plan view; Item 2. A method for manufacturing a light-emitting element, comprising: forming a second insulating film covering the light-emitting portion; removing a portion of the first insulating film to expose the first portion of the first electrode from the first insulating film and removing a portion of the second insulating film to expose a portion of the first semiconductor layer in the light-emitting portion from the second insulating film; forming a first wiring on the second insulating film that electrically connects the portion of the first semiconductor layer exposed from the second insulating film to the first portion of the first electrode exposed from the first insulating film; and separating the light-emitting portion from the second substrate after forming the first wiring. [Item 2] The method for manufacturing a light-emitting element according to Item 1, wherein in the step of separating the semiconductor structure into the plurality of light-emitting portions, the semiconductor structure is separated into the plurality of light-emitting portions such that the first electrode has a second portion located inside the outer edge of the light-emitting portion in a planar view. [Item 3] The method for manufacturing a light-emitting element according to Item 2, wherein the area of ​​the first portion is smaller than the area of ​​the second portion in a planar view.[Item 4] The method for manufacturing a light-emitting element according to any one of Items 1 to 3, further comprising a step of roughening the upper surface of the first semiconductor layer after the step of exposing the upper surface of the first semiconductor layer. [Item 5] The method for manufacturing a light-emitting element according to any one of Items 1 to 3, further comprising a step of roughening the upper surface and side surfaces of the light-emitting section after the step of separating the semiconductor structure into the plurality of light-emitting sections. [Item 6] The method for manufacturing a light-emitting element according to any one of Items 1 to 5, wherein in the step of forming the first wiring, the first wiring is formed of a light-transmitting conductive film. [Item 7] The method for manufacturing a light-emitting element according to any one of Items 1 to 6, wherein in the step of preparing a wafer, the wafer further includes a conductive layer disposed on the second semiconductor layer and electrically connected to the second electrode. [Item 8] The method for manufacturing a light-emitting element according to Item 7, wherein in the step of preparing a wafer, the wafer further includes a reflective film disposed between the conductive layer and the second electrode. [Item 9] The method for manufacturing a light-emitting element according to Item 8, wherein, in a plan view, the area of ​​the reflective film is 60% to 90% of the area of ​​the conductive layer. a first insulating film disposed on the second surface and having an opening that is located at a position overlapping with the second surface in a plan view; a first electrode disposed on the first insulating film and not connected to the second surface, the first electrode having a first portion located outside an outer edge of the semiconductor structure in a plan view; a second electrode disposed on the first insulating film and spaced apart from the first electrode, and electrically connected to the second semiconductor layer at the opening on the second surface; a second insulating film disposed on the first surface and on the side surface of the semiconductor structure; and a first wiring disposed on the second insulating film and electrically connecting a portion of the first semiconductor layer exposed from the second insulating film to the first portion of the first electrode exposed from the first insulating film.[Item 11] The light-emitting device according to Item 10, wherein, in a plan view, the first electrode has a second portion located inside the outer edge of the semiconductor structure. [Item 12] The light-emitting device according to Item 11, wherein, in a plan view, the area of ​​the first portion is smaller than the area of ​​the second portion. [Item 13] The light-emitting device according to any one of Items 10 to 12, wherein the first surface and the side surface of the semiconductor structure include a plurality of protrusions. [Item 14] The light-emitting device according to Item 13, wherein the arithmetic mean height of the first surface of the semiconductor structure including the plurality of protrusions is greater than the arithmetic mean height of the side surface of the semiconductor structure including the plurality of protrusions. [Item 15] The light-emitting device according to any one of Items 10 to 14, wherein the first wiring is made of a light-transmitting conductive film. [Item 16] The light-emitting device according to any one of Items 10 to 15, further comprising a conductive layer disposed on the second surface of the semiconductor structure, and electrically connected to the second semiconductor layer and the second electrode. [Item 17] The light-emitting element according to item 16, further comprising a reflective film disposed between the conductive layer and the second electrode. [Item 18] The light-emitting element according to item 17, wherein an area of ​​the reflective film is 60% to 90% of an area of ​​the conductive layer in a plan view.

[0107] The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. All forms that can be implemented by a person skilled in the art through appropriate design modifications based on the above-described embodiments of the present invention also fall within the scope of the present invention as long as they include the gist of the present invention. In addition, a person skilled in the art may come up with various modifications and alterations within the scope of the concept of the present invention, and these modifications and alterations also fall within the scope of the present invention.

[0108] 1 to 3...light-emitting element, 10...semiconductor structure, 10a...second surface, 10b...first surface, 10c...side surface, 10d...outer edge, 11...first semiconductor layer, 12...active layer, 13...second semiconductor layer, 20...first insulating film, 20a...first opening, 20b...second opening, 21...first layer, 22...second layer, 31...first electrode, 31a...first portion, 31b...second portion, 32...second electrode, 41...conductive layer, 42...reflective film, 51...bonding member, 52...second insulating film, 52a...third opening, 52b...fourth opening, 53...third insulating film, 61...first wiring, 100...light-emitting portion, 100d...outer edge, 101...first substrate, 102...second substrate, W...wafer

Claims

1. A process for producing a wafer including a first substrate, a semiconductor structure disposed on the first substrate, the semiconductor structure having a first semiconductor layer, a second semiconductor layer disposed further from the first substrate than the first semiconductor layer, and an active layer disposed between the first semiconductor layer and the second semiconductor layer, a first insulating film disposed on the second semiconductor layer and having an opening located above the second semiconductor layer, a first electrode disposed on the first insulating film, and a second electrode disposed on the first insulating film and spaced apart from the first electrode, the second electrode electrically connecting to the second semiconductor layer through the opening; a process for bonding a side of the wafer on which the second electrode and the first electrode are disposed to a second substrate; a process for removing the first substrate after the process for bonding the wafer to the second substrate, the process for exposing an upper surface of the first semiconductor layer; a process for removing a portion of the semiconductor structure from the upper surface side of the first semiconductor layer, and separating the semiconductor structure into a plurality of light emitting portions, the process being such that the first electrode has a first portion located outside an outer edge of the light emitting portion in a plan view; forming a second insulating film covering the light emitting portion; removing a portion of the first insulating film to expose the first portion of the first electrode from the first insulating film and removing a portion of the second insulating film to expose a portion of the first semiconductor layer of the light emitting portion from the second insulating film; forming a first wiring on the second insulating film that electrically connects the portion of the first semiconductor layer exposed from the second insulating film and the first portion of the first electrode exposed from the first insulating film; and separating the light emitting portion from the second substrate after forming the first wiring.

2. The method for manufacturing a light-emitting element as described in claim 1, wherein, in the step of separating the semiconductor structure into the plurality of light-emitting sections, the semiconductor structure is separated into the plurality of light-emitting sections such that, in a planar view, the first electrode has a second portion that is located inside the outer edge of the light-emitting section.

3. The method for manufacturing a light-emitting element according to claim 2, wherein, in a plan view, an area of ​​the first portion is smaller than an area of ​​the second portion.

4. A method for manufacturing a light-emitting element according to any one of claims 1 to 3, further comprising the step of roughening the upper surface of the first semiconductor layer after the step of exposing the upper surface of the first semiconductor layer.

5. A method for manufacturing a light-emitting element according to any one of claims 1 to 3, further comprising the step of roughening the top and side surfaces of the light-emitting portions after the step of separating the semiconductor structure into the plurality of light-emitting portions.

6. The method for manufacturing a light-emitting element according to any one of claims 1 to 3, wherein in the step of forming the first wiring, the first wiring is formed from a light-transmitting conductive film.

7. A method for manufacturing a light-emitting element according to any one of claims 1 to 3, wherein in the step of preparing the wafer, the wafer further includes a conductive layer disposed on the second semiconductor layer and electrically connected to the second electrode.

8. The method for manufacturing a light-emitting element according to claim 7, wherein in the step of preparing a wafer, the wafer further includes a reflective film disposed between the conductive layer and the second electrode.

9. The method for manufacturing a light-emitting element according to claim 8, wherein the area of ​​the reflective film is 60% or more and 90% or less of the area of ​​the conductive layer in a plan view.

10. A light-emitting element comprising: a semiconductor structure having a first surface, a second surface located opposite to the first surface, and a side surface connecting the first surface and the second surface, the semiconductor structure having a first semiconductor layer located on the first surface side, a second semiconductor layer located on the second surface side, and an active layer located between the first semiconductor layer and the second semiconductor layer; a first insulating film disposed on the second surface and having an opening disposed at a position overlapping with the second surface in a planar view; a first electrode disposed on the first insulating film and not connected to the second surface, the first electrode having a first portion located outside an outer edge of the semiconductor structure in a planar view; a second electrode disposed on the first insulating film and spaced apart from the first electrode, and electrically connected to the second semiconductor layer on the second surface through the opening; a second insulating film disposed on the first surface and on the side surface of the semiconductor structure; and a first wiring disposed on the second insulating film and electrically connecting a part of the first semiconductor layer exposed from the second insulating film to the first portion of the first electrode exposed from the first insulating film.

11. The light-emitting element according to claim 10, wherein the first electrode has a second portion located inside the outer edge of the semiconductor structure in a plan view.

12. The light-emitting element according to claim 11, wherein an area of ​​the first portion is smaller than an area of ​​the second portion in a plan view.

13. The light-emitting element according to claim 10, wherein the first surface and the side surface of the semiconductor structure include a plurality of protrusions.

14. The light-emitting element according to claim 13, wherein the arithmetic mean height of the first surface of the semiconductor structure including the plurality of protrusions is greater than the arithmetic mean height of the side surface of the semiconductor structure including the plurality of protrusions.

15. The light-emitting element according to any one of claims 10 to 12, wherein the first wiring is made of a light-transmitting conductive film.

16. The light-emitting device according to any one of claims 10 to 12, further comprising a conductive layer disposed on the second surface of the semiconductor structure and electrically connected to the second semiconductor layer and the second electrode.

17. The light-emitting device according to claim 16, further comprising a reflective film disposed between the conductive layer and the second electrode.

18. The light-emitting element according to claim 17, wherein the area of ​​the reflective film is 60% or more and 90% or less of the area of ​​the conductive layer in a plan view.