Method for manufacturing a light-emitting element and a light-emitting element

Abstract

To provide a method for manufacturing a light-emitting element having high reliability, and a light-emitting element manufactured by the method.SOLUTION: A method for manufacturing a light-emitting element includes the steps of: preparing a semiconductor structure where an n-side layer includes a plurality of first regions arranged in a first direction in a top view, the first regions being exposed from an active layer and a p-side layer; forming a first insulating film on the p-side layer, between the first regions; forming a second insulating film to continuously cover the first regions, the p-side layer, and the first insulating film; forming, in the second insulating film, an n-side opening exposing the first regions and the first insulating film from the second insulating film, the n-side opening being continuous in the first direction in a top view; and forming an n-side electrode in the n-side opening, the n-side electrode contacting the first regions and the first insulating film. In a top view, a width of the n-side opening in a second direction orthogonal to the first direction is equal to or less than a width of the first insulating film in the second direction.SELECTED DRAWING: Figure 2

Description

Technical Field

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

Background Art

[0002] Patent Document 1 discloses a light-emitting element in which an n-side power supply portion provided via a power supply insulating layer is disposed on a p-type semiconductor layer.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to provide a method for manufacturing a light-emitting element having high reliability and a light-emitting element.

Means for Solving the Problems

[0005] According to one aspect of the present invention, a method for manufacturing a light-emitting element comprises the steps of: preparing a semiconductor structure having an n-side layer, a p-side layer, and an active layer located between the n-side layer and the p-side layer, wherein the n-side layer is exposed from the active layer and the p-side layer and has a plurality of first regions arranged in a first direction in a top view; forming a first insulating film on the p-side layer located between the plurality of first regions; forming a second insulating film that continuously covers the first regions, the p-side layer, and the first insulating film; removing the second insulating film on the first regions and the first insulating film to form an n-side opening in the second insulating film that is continuous in the first direction in a top view and exposes the first regions and the first insulating film from the second insulating film; and forming an n-side electrode in the n-side opening that is in contact with the first regions and the first insulating film, wherein in a top view, the width of the n-side opening in a second direction perpendicular to the first direction is less than or equal to the width of the first insulating film in the second direction.

[0006] According to one aspect of the present invention, a light-emitting element is a semiconductor structure having an n-side layer, a p-side layer, and an active layer located between the n-side layer and the p-side layer, wherein the n-side layer is exposed from the active layer and the p-side layer and has a plurality of first regions arranged in a first direction in a top view, a first insulating film disposed on the p-side layer located between the plurality of first regions, a second insulating film disposed on the first region, the p-side layer, and the first insulating film, the second insulating film being continuous in the first direction in a top view and having an n-side opening that exposes the first region and the first insulating film, and an n-side electrode disposed in the n-side opening and in contact with the first region and the first insulating film, wherein in a top view, the width of the n-side opening in a second direction perpendicular to the first direction is less than or equal to the width of the first insulating film in the second direction. [Effects of the Invention]

[0007] According to the present invention, a method for manufacturing a light-emitting element and a light-emitting element with high reliability can be provided. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic top view of the light-emitting element of the first embodiment. [Figure 2] This is an enlarged top view of section A in Figure 1. [Figure 3] This is a schematic cross-sectional view along line III-III in Figure 2. [Figure 4] Figure 2 is a schematic cross-sectional view along line IV-IV. [Figure 5] Figure 2 is a schematic cross-sectional view of the VV line. [Figure 6] This is a schematic top view illustrating one step in the manufacturing method of the light-emitting element according to the first embodiment. [Figure 7] This is a schematic top view illustrating one step in the manufacturing method of the light-emitting element according to the first embodiment. [Figure 8] This is a schematic top view illustrating one step in the manufacturing method of the light-emitting element according to the first embodiment. [Figure 9] This is a schematic top view illustrating one step in the manufacturing method of the light-emitting element according to the first embodiment. [Figure 10] This is a schematic top view illustrating one step in the manufacturing method of the light-emitting element according to the first embodiment. [Figure 11] This is a schematic top view of a portion of a light-emitting element according to a first modification of the first embodiment. [Figure 12] Figure 11 is a schematic cross-sectional view along line XII-XII. [Figure 13] This is a schematic top view of a portion of a light-emitting element according to a second modification of the first embodiment. [Figure 14] This is a schematic top view of the light-emitting element of the second embodiment. [Figure 15] This is a schematic top view of the light-emitting element of the third embodiment. [Figure 16] Figure 15 is a schematic cross-sectional view along the line XVI-XVI. [Figure 17] This is a schematic top view illustrating one step in the manufacturing method of a light-emitting element according to the third embodiment. [Modes for carrying out the invention]

[0009] Hereinafter, embodiments will be described with reference to the drawings. Dimensions, materials, shapes, relative arrangements, etc. of the components described in the embodiments are not intended to be limited thereto only, but are merely illustrative examples unless otherwise specifically described. Note that the sizes, positional relationships, etc. of the members shown in each drawing may be exaggerated for clarity of explanation. In the following description, the same names and reference numerals indicate the same or similar members, and detailed descriptions will be omitted as appropriate. Also, as a cross-sectional view, there may be an end view showing only the cut surface.

[0010] In the following description, terms indicating a specific direction or position (for example, "up", "down", and other terms including those terms) may be used. However, those terms are merely used for ease of understanding of the relative direction or position in the referenced drawing. As long as the relative direction or positional relationship by terms such as "up", "down", etc. in the referenced drawing is the same, in drawings other than the present disclosure, actual products, etc., they do not have to be arranged in the same way as in the referenced drawing. In this specification, the positional relationship expressed as "above (or below)" means, for example, when assuming there are two members, the case where the two members are in contact, and the case where the two members are not in contact and one member is located above (or below) the other member. Also, in this specification, unless otherwise specifically described, a member covering a covered object includes both the case where the member directly covers the covered object in contact with the covered object and the case where the member indirectly covers the covered object without contact with the covered object. Also, in this specification, the width of a member in a specific direction represents the maximum value of the width in the specific direction.

[0011] In the figures shown below, the directions may be indicated by the X-axis, Y-axis, and Z-axis. The X-axis, Y-axis, and Z-axis are perpendicular to each other. For example, in this specification, the direction along the X-axis is the first direction X, the direction along the Y-axis is the second direction Y, and the direction along the Z-axis is the third direction Z.

[0012] [First Embodiment] Referring to FIGS. 1 to 5, the light-emitting element 1 of the first embodiment will be described. The light-emitting element 1 includes a semiconductor structure 10, a first insulating film 30, a second insulating film 40, and an n-side electrode 50. Hereinafter, the details of each component will be described.

[0013] <Semiconductor structure> The semiconductor structure 10 is made of a nitride semiconductor. In this specification, the "nitride semiconductor" refers to, for example, In x Al y Ga 1-x-y All semiconductors with composition ratios x and y varied within their respective ranges in the chemical formula N(0≦x≦1, 0≦y≦1, x + y≦1) are included. Also, in the above chemical formula, those further containing group V elements other than N (nitrogen), and those further containing various elements added to control various physical properties such as conductivity type are also included in the "nitride semiconductor".

[0014] As shown in FIGS. 3 to 5, the semiconductor structure 10 has an n-side layer 11, a p-side layer 13, and an active layer 12 located between the n-side layer 11 and the p-side layer 13 in the third direction Z. The active layer 12 is a light-emitting layer that emits light and has, for example, a MQW (Multiple Quantum Well) structure including a plurality of barrier layers and a plurality of well layers. The active layer 12 emits light with a peak wavelength of, for example, 210 nm or more and 580 nm or less. The n-side layer 11 has a semiconductor layer containing n-type impurities. The p-side layer 13 has a semiconductor layer containing p-type impurities. The light emitted by the active layer 12 is mainly taken out to the outside from the light-emitting surface 10a of the light-emitting element 1 shown in FIG. 1.

[0015] The light-emitting element 1 can further include a substrate 100 that supports the semiconductor structure 10. For example, the substrate 100 is a substrate for growing the semiconductor structure 10. The substrate 100 can be, for example, an insulating substrate such as sapphire or spinel (MgA12O4) having any one of the C plane, R plane, and A plane as the main plane. Also, as the substrate 100, a conductive substrate such as SiC (including 6H, 4H, 3C), ZnS, ZnO, GaAs, Si, etc. may be used. In the light-emitting element 1, the substrate 100 may not be provided.

[0016] The shape of the semiconductor structure 10 in a top view is, for example, rectangular. In the first embodiment, the shape of the semiconductor structure 10 in a top view is rectangular. As shown in Figure 1, the semiconductor structure 10 has a first outer edge 10A, a second outer edge 10B, a third outer edge 10C, and a fourth outer edge 10D in a top view. The first outer edge 10A and the second outer edge 10B extend in a first direction X, and the third outer edge 10C and the fourth outer edge 10D extend in a second direction Y. In a top view, the first outer edge 10A and the second outer edge 10B are separated in the second direction Y, and the third outer edge 10C and the fourth outer edge 10D are separated in the first direction X. In the example shown in Figure 1, the lengths of the first outer edge 10A and the second outer edge 10B are longer than the lengths of the third outer edge 10C and the fourth outer edge 10D. The outer periphery of the semiconductor structure 10 includes an n-side layer 11, an active layer 12 disposed on the n-side layer 11, and a p-side layer 13 disposed on the active layer 12. A first insulating film 30 is disposed on the p-side layer 13 of the outer periphery of the semiconductor structure 10. The outer periphery of the semiconductor structure 10 represents the area within 20 μm inward from the first outer edge 10A to the fourth outer edge 10D of the semiconductor structure 10.

[0017] As shown in Figures 3 to 5, the n-side layer 11 has a first region 11a that is exposed from the active layer 12 and the p-side layer 13. On the surface of the semiconductor structure 10 opposite to the surface in contact with the substrate 100, the only region of the n-side layer 11 that is exposed from the active layer 12 and the p-side layer 13 is the first region 11a. As shown in Figures 1 and 2, in a top view, multiple first regions 11a are arranged side by side, spaced apart from each other in a first direction X. For example, in a top view, multiple first regions 11a are arranged in the first direction X at a position closer to the first outer edge 10A than to the second outer edge 10B. In a top view, the first region 11a is, for example, circular in shape. Alternatively, in a top view, the first region 11a may be quadrilateral or a polygon with pentagons or more.

[0018] <First insulating film> As shown in Figures 2 and 3, the first insulating film 30 is arranged on a p-side layer 13 located between a plurality of first regions 11a aligned in the first direction X. Between two adjacent first regions 11a in the first direction X, the first insulating film 30 extends in the first direction X. The first insulating film 30 covers the upper surface of the p-side layer 13.

[0019] As shown in Figure 3, the end portion 30a in the first direction X of the first insulating film 30 covers the side surface of the p-side layer 13, the side surface of the active layer 12, and the side surface of the n-side layer 11, which are continuous between the upper surface of the p-side layer 13 and the first region 11a.

[0020] The first insulating film 30 is transparent to light emitted by the active layer 12. The first insulating film 30 has a transmittance of 60% or more, preferably 70% or more, to light emitted by the active layer 12. The first insulating film 30 is, for example, a silicon nitride film. Alternatively, a silicon oxide film may be used as the first insulating film 30. A silicon nitride film absorbs light in the wavelength range described above emitted by the active layer 12 more easily than a silicon oxide film. Therefore, when a silicon nitride film is used as the first insulating film 30, it is preferable that the width in the second direction Y of the first insulating film 30 located between a plurality of first regions 11a aligned in the first direction X in a top view is smaller than the width in the second direction Y of the first region 11a. This makes it possible to reduce the light absorption region by the first insulating film 30 on the light-emitting surface 10a of the light-emitting element 1. In addition, an aluminum oxide film, a titanium oxide film, etc., can be used as the first insulating film 30.

[0021] <Second insulating film> The second insulating film 40 is arranged on the first region 11a, on the p-side layer 13, and on the first insulating film 30. As shown in Figure 4, the portions of the p-side layer 13, the active layer 12, and the n-side layer 11 that are continuous between the upper surface of the p-side layer 13 and the first region 11a, where the first insulating film 30 is not present, are covered by the second insulating film 40. Also, as shown in Figure 5, the second insulating film 40 covers the sides of the first insulating film 30.

[0022] As shown in FIG. 2, the second insulating film 40 has an n-side opening 41 that is continuous in the first direction X in a top view. In the n-side opening 41, the first region 11a and the first insulating film 30 are exposed from the second insulating film 40.

[0023] In a top view, the width of the n-side opening 41 in the second direction Y is equal to or less than the width of the first insulating film 30 in the second direction Y. In the example shown in FIG. 2, the width of the n-side opening 41 in the second direction Y is smaller than the width of the first insulating film 30 in the second direction Y.

[0024] The n-side opening 41 has a first opening 41a located on the first region 11a and a second opening 41b located on the first insulating film 30. The first opening 41a and the second opening 41b are continuous in the first direction X. In the example shown in FIG. 2, the width of the first opening 41a in the second direction Y is the same as the width of the second opening 41b in the second direction Y.

[0025] The second insulating film 40 has permeability to light emitted by the active layer 12. The second insulating film 40 has a transmittance of 60% or more, preferably 80% or more, with respect to the light emitted by the active layer 12. The second insulating film 40 is, for example, a silicon oxynitride film. Alternatively, a silicon oxide film, an aluminum oxide film, a titanium oxide film, or the like can be used as the second insulating film 40.

[0026] <n-side electrode> The n-side electrode 50 is disposed in the n-side opening 41 and contacts the first region 11a and the first insulating film 30. As shown in FIGS. 3 and 4, the n-side electrode 50 has a first portion 51 located in the first opening 41a of the n-side opening 41. By the first portion 51 contacting the first region 11a, the n-side electrode 50 is electrically connected to the n-side layer 11.

[0027] Also, as shown in FIG. 5, the n-side electrode 50 has a second portion 52 located in the second opening portion 41b of the n-side opening 41. The first portion 51 and the second portion 52 are continuous in the first direction X. The second portion 52 is located on the first insulating film 30. Since the first insulating film 30 is disposed between the n-side electrode 50 and the p-side layer 13, it is possible to reduce the likelihood of generating a leakage current between the n-side electrode 50 and the p-side layer 13, thereby improving reliability. In order to reduce the likelihood of generating a leakage current between the n-side electrode 50 and the p-side layer 13, the thickness of the first insulating film 30 is preferably greater than the thickness of the second insulating film 40. Here, the thickness of the first insulating film 30 represents the thickness in the direction connecting the upper surface of the p-side layer 13 and the lower surface of the n-side electrode 50 at the shortest distance. Also, the thickness of the second insulating film 40 represents the shortest distance between the lower surface located on the p-side layer 13 side and the upper surface located on the opposite side of the lower surface in the third direction.

[0028] As shown in FIG. 1, the n-side electrode 50 further has a third portion 53. The third portion 53 is continuous with one end portion of the second portion 52 in the first direction X. The third portion 53 is located near, for example, the corner formed by the first outer edge 10A and the fourth outer edge 10D of the semiconductor structure 10 in a top view.

[0029] The width of the third portion 53 in the second direction Y is greater than the width of the first portion 51 in the second direction Y and the width of the second portion 52 in the second direction Y. For example, a conductive wire is connected to the third portion 53, and the n-side electrode 50 is electrically connected to an external circuit through the conductive wire.

[0030] In FIG. 1, the first insulating film 30 is represented by a hatching. The first insulating film 3也0 is also disposed under the third portion也 Also, the third portion 53 is disposed on the p-side layer 13 via the first insulating film 30, and it is possible to reduce the likelihood of generating a leakage current between the third portion 53 and the p-side layer 13, thereby improving reliability.

[0031] <p-side electrode> As shown in Figure 1, the light-emitting element 1 further comprises a p-side electrode 60. The p-side electrode 60 is positioned in a p-side opening 42 formed in a second insulating film 40 located on the p-side layer 13 and is electrically connected to the p-side layer 13. For example, the p-side electrode 60 has a p-side extension portion 61 extending in a first direction X and a p-side pad portion 62 continuous with one end of the p-side extension portion 61 in the first direction X. The width of the p-side pad portion 62 in the second direction Y is greater than the width of the p-side extension portion 61 in the second direction Y. For example, a conductive wire is connected to the p-side pad portion 62, and the p-side electrode 60 is electrically connected to an external circuit through the conductive wire.

[0032] Metal materials such as Rh, Pt, Au, and Cu can be used as the materials for the n-side electrode 50 and the p-side electrode 60.

[0033] <Transparent conductive layer> As shown in Figures 4 and 5, the light-emitting element 1 may further include a translucent conductive layer 20 disposed on the p-side layer 13. The translucent conductive layer 20 is covered with a second insulating film 40.

[0034] The translucent conductive layer 20 is in contact with the upper surface of the p-side layer 13. The p-side electrode 60 is positioned on the translucent conductive layer 20 and is in contact with the upper surface of the translucent conductive layer 20. Therefore, the p-side electrode 60 is electrically connected to the p-side layer 13 via the translucent conductive layer 20. The translucent conductive layer 20 has the function of diffusing the current supplied through the p-side electrode 60 in the planar direction of the p-side layer 13. This reduces brightness unevenness on the light-emitting surface 10a of the light-emitting element 1. The translucent conductive layer 20 is also transparent to the light emitted by the active layer 12. The translucent conductive layer 20 has a transmittance of 60% or more, preferably 70% or more, to the light emitted by the active layer 12.

[0035] For example, ITO (Indium Tin Oxide), ZIO (Zinc Indium Oxide), ZnO, In2O3, etc., can be used as the material for the translucent conductive layer 20. The thickness of the translucent conductive layer 20 can be, for example, 30 nm to 200 nm.

[0036] In Figure 1, the outer edge of the translucent conductive layer 20 located beneath the second insulating film 40 is shown by a dashed line. In the example shown in Figure 1, in a top view, the translucent conductive layer 20 is positioned so as not to overlap with the first insulating film 30. The first insulating film 30 is in contact with the upper surface of the p-side layer 13 directly beneath the n-side electrode 50. Since the translucent conductive layer 20 is not positioned directly beneath the n-side electrode 50, leakage current between the n-side electrode 50 and the translucent conductive layer 20 can be reduced.

[0037] In addition, when viewed from above, the translucent conductive layer 20 may be positioned to overlap with the first insulating film 30. In this case, the first insulating film 30 is positioned between the translucent conductive layer 20 and the n-side electrode 50 while diffusing the current to the p-side layer 13 directly beneath the first insulating film 30, making it less likely for leakage current to occur between the n-side electrode 50 and the p-side layer 13.

[0038] Next, the manufacturing method of the light-emitting element 1 according to the first embodiment will be described with reference to Figures 6 to 10. The regions shown in Figures 6 to 10 correspond to the regions shown in Figure 2. Each component constituting the light-emitting element 1 has been described above, and detailed explanations may be omitted as appropriate.

[0039] <Process for preparing semiconductor structures> The manufacturing method for the light-emitting element 1 includes a step of preparing a semiconductor structure 10. The semiconductor structure 10 has an n-side layer 11, a p-side layer 13, and an active layer 12 located between the n-side layer 11 and the p-side layer 13. In the step of preparing the semiconductor structure 10, for example, the n-side layer 11, the active layer 12, and the p-side layer 13 are formed sequentially on a substrate 100 by the MOCVD (Metal Organic Chemical Vapor Deposition) method.

[0040] Furthermore, as shown in Figure 6, the n-side layer 11 has a first region 11a exposed from the active layer 12 and the p-side layer 13. In a top view, multiple first regions 11a are arranged side by side, spaced apart from each other in the first direction X. The first regions 11a can be formed by removing the p-side layer 13 and the active layer 12. The removal of the p-side layer 13 and the active layer 12 can be carried out, for example, by the RIE (Reactive Ion Etching) method.

[0041] The process of preparing the semiconductor structure 10 includes forming a translucent conductive layer 20. As shown in Figure 7, the translucent conductive layer 20 is formed in the region of the p-side layer 13, excluding the area between the first regions 11a, when viewed from above. The translucent conductive layer 20 is not placed between the first regions 11a aligned in the first direction X; that is, the translucent conductive layer 20 is not placed in the region where the n-side electrode 50 will be placed in a later step. Note that the translucent conductive layer 20 may be omitted.

[0042] For example, after forming a translucent conductive layer 20 on the entire upper surface of the semiconductor structure 10 including the upper surface of the p-side layer 13 and the first region 11a, the translucent conductive layer 20 on the first region 11a and on the p-side layer 13 between the first region 11a is removed by etching using a resist mask. The removal of the translucent conductive layer 20 is performed, for example, by wet etching. Wet etching is performed using, for example, hydrochloric acid, nitric acid, or a mixture of hydrochloric acid and nitric acid.

[0043] The following describes the case where the light-transmitting conductive layer 20 is formed.

[0044] <Step to form the first insulating film> The manufacturing method for the light-emitting element 1 includes the step of forming a translucent conductive layer 20, followed by the step of forming a first insulating film 30. As shown in Figure 8, the first insulating film 30 is formed on a p-side layer 13 located between a plurality of first regions 11a aligned in the first direction X.

[0045] For example, a silicon nitride film is formed as the first insulating film 30. For example, after forming a resist mask so as to expose the upper surface of the p-side layer 13 between a plurality of first regions 11a, the first insulating film 30 is formed by sputtering or CVD. After this, the resist mask is removed, thereby removing the first insulating film 30 formed on the resist mask together with the resist mask. This makes it possible to form the first insulating film 30 located on the p-side layer 13 between a plurality of first regions 11a.

[0046] In the example shown in Figure 8, in a top view, the width of the first insulating film 30 in the second direction Y is smaller than the width of the first region 11a in the second direction Y. As a result, as described above, the light absorption region by the first insulating film 30 on the light-emitting surface 10a of the light-emitting element 1 can be reduced.

[0047] The manufacturing method for the light-emitting element 1 preferably further includes a step of heat-treating the semiconductor structure 10 after the step of forming the first insulating film 30. It is believed that the heat treatment of the semiconductor structure 10 causes hydrogen incorporated into the p-side layer 13 due to the raw material gas used when forming the p-side layer 13 to be desorbed from the p-side layer 13. The desorption of hydrogen from the p-side layer 13 activates the p-side layer 13, and the electrical resistance of the p-side layer 13 is reduced, thereby increasing the luminous efficiency of the light-emitting element 1.

[0048] There is no translucent conductive layer 20 directly beneath the first insulating film 30, and the first insulating film 30 and the p-side layer 13 are in contact in the region between the first regions 11a. In the heat treatment process described above, hydrogen does not easily diffuse from the p-side layer 13 to the first insulating film 30, and the p-side layer 13 in contact with the first insulating film 30 is not easily activated. Therefore, in the p-side layer 13, the region between the first regions 11a has a higher electrical resistance than the region where the translucent conductive layer 20 is formed. The region between the first regions 11a is the region where the n-side electrode 50, described later, is formed, and the increased electrical resistance of the p-side layer 13 between the first regions 11a makes it difficult to generate leakage current between the n-side electrode 50 and the p-side layer 13. This makes it possible to increase the reliability of the light-emitting element 1.

[0049] By forming the first insulating film 30 only on the p-side layer 13 located between the plurality of first regions 11a, it becomes possible to reduce the electrical resistance of regions other than the region under the n-side electrode 50 in the p-side layer 13 by the above-described heat treatment.

[0050] <Step of forming the second insulating film> The method for manufacturing the light-emitting device 1 includes a step of forming a second insulating film 40 after the step of forming the first insulating film 30. When performing the step of heat-treating the semiconductor structure 10, the second insulating film 40 is formed after the step of heat-treating the semiconductor structure 10.

[0051] As shown in FIG. 9, the second insulating film 40 continuously covers the first region 11a, the p-side layer 13, the transparent conductive layer 20, and the first insulating film 30. For example, the second insulating film 40 is formed by a sputtering method or a CVD method.

[0052] <Step of forming the n-side opening> The method for manufacturing the light-emitting device 1 includes a step of forming an n-side opening 41 in the second insulating film 40. The second insulating film 40 on the first region 11a and the first insulating film 30 is removed. As a result, as shown in FIG. 10, an n-side opening 41 that is continuous in the first direction X in a top view and exposes the first region 11a and the first insulating film 30 from the second insulating film 40 is formed.

[0053] For example, a resist mask is formed on the second insulating film 40, and the n-side opening 41 is formed by etching away the second insulating film 40. In the process of forming the n-side opening 41 in the second insulating film 40, it is preferable to remove the second insulating film 40 under etching conditions in which the etching rate for the second insulating film 40 is higher than the etching rate for the first insulating film 30. For example, when the first insulating film 30 is a silicon nitride film and the second insulating film 40 is a silicon oxynitride film, the second insulating film 40 is removed by wet etching using BHF (Buffered Hydrofluoric Acid). In this case, the etching rate for the first insulating film 30 is 1 / 10 or less of the etching rate for the second insulating film 40. This reduces the reduction in the thickness of the first insulating film 30 when forming the n-side opening 41, and makes it less likely for leakage current to occur between the n-side electrode 50 and the p-side layer 13.

[0054] Furthermore, in order to ensure that a thick layer of the first insulating film 30 remains on the p-side layer 13 even if the first insulating film 30 is etched during the process of forming the n-side opening 41, it is preferable to make the thickness of the first insulating film 30 thicker than the thickness of the second insulating film 40 during the process of forming the first insulating film 30. For example, the thickness of the first insulating film 30 can be 50 nm or more and 1000 nm or less, and is preferably 200 nm or more and 400 nm or less. For example, the thickness of the second insulating film 40 can be 10 nm or more and 300 nm or less, and is preferably 50 nm or more and less than 200 nm.

[0055] The n-side opening 41 has a first opening 41a located on the first region 11a and a second opening 41b located on the first insulating film 30. The first opening 41a and the second opening 41b are continuous in the first direction X.

[0056] In a top view, the width in the second direction Y of the n-side opening 41 located on the first insulating film 30 is equal to or less than the width in the second direction Y of the first insulating film 30. Thereby, the n-side electrode 50 formed in the n-side opening 41 in a subsequent process is less likely to protrude from the first insulating film 30 in the second direction Y. As a result, since the n-side electrode 50 and the p-side layer 13 do not come into contact with each other, it is possible to make it difficult for the n-side electrode 50 and the p-side layer 13 to short-circuit.

[0057] In the present embodiment, an n-side opening 41 that is continuous in the first direction X is formed in a top view so as to expose the first region 11a and the first insulating film 30 from the second insulating film 40. That is, the n-side opening 41 is formed so as to be continuous between the plurality of first regions 11a. Thereby, it is easier to form the n-side opening 41 than to partially form a plurality of n-side openings according to the positions of the plurality of first regions 11a. Particularly when forming an opening by exposure and development on a resist mask, it is easier to form an opening continuous in the first direction X than to form a plurality of relatively small openings in the resist mask. By removing the second insulating film 40 exposed in the opening continuous in the first direction X formed in the resist mask by etching, the n-side opening 41 is formed so as to be continuous between the plurality of first regions 11a. Since the first insulating film 30 is formed on the p-side layer 13 between the plurality of first regions 11a, the p-side layer 13 is not exposed in the n-side opening 41. <……>

[0058] <Step of forming n-side electrode> The method for manufacturing the light-emitting element 1 includes a step of forming an n-side electrode 50 in the n-side opening 41 after the step of forming the n-side opening 41. As shown in FIGS. 3 to 5 described above, the n-side electrode 50 contacts the first region 11a and the first insulating film 30 in the n-side opening 41. The n-side electrode 50 can be formed by, for example, a sputtering method, a vapor deposition method, or the like.

[0059] The manufacturing method for the light-emitting element 1 includes a step of forming the p-side electrode 60. For example, in the step of forming the n-side opening 41 in the second insulating film 40 described above, the p-side opening 42 is formed in the second insulating film 40 at the same time as the n-side opening 41. At the p-side opening 42, the translucent conductive layer 20 is exposed from the second insulating film 40. Then, the p-side electrode 60 is formed on the translucent conductive layer 20 located at the p-side opening 42. As a result, the p-side electrode 60 is electrically connected to the p-side layer 13 via the translucent conductive layer 20.

[0060] Through the process described above, for example, a wafer is formed on a single substrate in which multiple light-emitting regions are formed, and then the wafer is divided into multiple individual light-emitting elements 1.

[0061] Figure 11 is a schematic top view of a portion of a light-emitting element according to a first modification of the first embodiment. Figure 12 is a schematic cross-sectional view taken along the line XII-XII in Figure 11.

[0062] In the first modified example, in a top view, the width of the first opening 41a of the n-side opening 41 in the second direction Y is greater than the width of the second opening 41b of the n-side opening 41 in the second direction Y. Also, in a top view, the width of the first portion 51 of the n-side electrode 50 in the second direction Y is greater than the width of the second portion 52 of the n-side electrode 50 in the second direction Y. The first portion 51 overlaps with the outer edge of the first opening 41a in a top view. This allows for a larger contact area between the n-side electrode 50 and the first region 11a compared to the case where the width of the first portion 51 in the second direction Y is less than or equal to the width of the second portion 52 in the second direction Y, thereby reducing the contact resistance between the n-side electrode 50 and the first region 11a. Furthermore, since the second portion 52, which has a smaller width in the second direction Y than the first portion 51, is located on the p-side layer 13 between the multiple first regions 11a, light absorption by the n-side electrode 50 on the p-side layer 13 between the multiple first regions 11a can be reduced.

[0063] Furthermore, in a top view, the width W2 of the first portion 51 of the n-side electrode 50 in the second direction Y is greater than or equal to the width W1 of the first opening 41a of the n-side opening 41 in the second direction Y, and less than or equal to the width W3 of the first region 11a in the second direction Y. The first portion 51 of the n-side electrode 50 does not overlap with the outer edge of the first region 11a in a top view.

[0064] By making the width W2 of the first portion 51 greater than or equal to the width W1 of the first opening 41a, the first region 11a exposed at the first opening 41a can be covered by the first portion 51, as shown in Figure 12. At the first opening 41a, the first region 11a is not exposed from the first portion 51. This protects the first region 11a and reduces the occurrence of oxidation and other issues.

[0065] Furthermore, by making the width W2 of the first portion 51 less than or equal to the width W3 of the first region 11a, the first portion 51 does not lie on the p-side layer 13, and the light absorption caused by the n-side electrode 50 lying on the p-side layer 13 can be reduced.

[0066] Figure 13 is a schematic top view of a portion of a light-emitting element according to a second modification of the first embodiment. In the first embodiment, multiple first insulating films 30 are arranged, whereas in the second modification of the first embodiment, only one first insulating film 30 is arranged. Figure 13 shows the arrangement relationship between the first insulating film 30 and the first region 11a in a top view.

[0067] In the first region 11a, leakage current is particularly likely to occur between the outer edge 11o and the p-side layer 13. According to the second modification, in a top view, the width of the first insulating film 30 in the second direction Y is larger than the width of the first region 11a in the second direction Y, and the first insulating film 30 continuously covers the outer edges 11o of multiple first regions 11a. This makes it less likely for leakage current to occur between the outer edges 11o of the first region 11a and the p-side layer 13.

[0068] The first insulating film 30 continuously covers a plurality of first regions 11a and extends continuously in the first direction X. A plurality of third openings 31 are formed in the first insulating film 30, corresponding to the plurality of first regions 11a. At the third openings 31, the first regions 11a are exposed from the first insulating film 30.

[0069] [Second Embodiment] Referring to Figure 14, the light-emitting element 2 of the second embodiment will be described. In Figure 14, the first insulating film 30 is represented by a shaded area.

[0070] According to the second embodiment, in a top view, the first insulating film 30 is arranged on the p-side layer 13 located between the multiple first regions 11a and on the outer periphery of the semiconductor structure 10. As shown in Figure 14, the first insulating film 30 can be provided continuously on the p-side layer 13 located between the multiple first regions 11a and on the outer periphery of the semiconductor structure 10. The translucent conductive layer 20 is not arranged on the outer periphery of the semiconductor structure 10. In a top view, the outer periphery of the semiconductor structure 10 represents the area within 20 μm inward from the first outer edge 10A to the fourth outer edge 10D of the semiconductor structure 10.

[0071] The outer periphery of the semiconductor structure 10 includes an n-side layer 11, an active layer 12 disposed on the n-side layer 11, and a p-side layer 13 disposed on the active layer 12. A first insulating film 30 is disposed on the p-side layer 13 of the outer periphery of the semiconductor structure 10. The electrical resistance of the p-side layer 13 in the region located below the first insulating film 30 is higher than the electrical resistance of the p-side layer 13 in the region not located below the first insulating film 30. In other words, the electrical resistance of the p-side layer 13 in the outer periphery is higher than the electrical resistance of the p-side layer 13 inward from the outer periphery. This makes it difficult to generate leakage current between the p-side layer 13 and the n-side layer 11 via the semiconductor debris, even if semiconductor debris adheres to the outer surface of the semiconductor structure 10.

[0072] In the manufacturing process of the light-emitting element 2, the first insulating film 30 is formed in the region where the n-side electrode 50 is placed in the wafer state before it is separated into individual light-emitting elements, and in the region that will become the outer periphery of the semiconductor structure 10 in the light-emitting element after it has been separated. In the wafer state before it is separated into individual light-emitting elements, the first insulating film 30 is formed, for example, in a grid pattern when viewed from above. By placing the first insulating film 30 on the p-side layer 13 of the outer periphery of the semiconductor structure 10, hydrogen is less likely to detach from the p-side layer 13 in the outer periphery during the heat treatment of the semiconductor structure 10 described above, and the electrical resistance of the p-side layer 13 in the outer periphery is less likely to decrease. As a result, for example, even if semiconductor waste generated when the wafer is divided adheres to the outer surface of the semiconductor structure 10, it is possible to make it less likely for leakage current to be generated between the p-side layer 13 and the n-side layer 11 via the semiconductor waste.

[0073] [Third Embodiment] The light-emitting element 3 of the third embodiment will be described with reference to Figures 15 to 17. In Figure 15, the first insulating film 30 is represented by a shaded area.

[0074] According to the third embodiment, a third insulating film 70, separate from the first insulating film 30, is arranged on the outer periphery of the semiconductor structure 10. As shown in Figure 16, the third insulating film 70 is arranged on the p-side layer 13 on the outer periphery of the semiconductor structure 10. The electrical resistance of the p-side layer 13 in the region located below the third insulating film 70 is higher than the electrical resistance of the p-side layer 13 in the region not located below the third insulating film 70. In other words, the electrical resistance of the p-side layer 13 on the outer periphery is higher than the electrical resistance of the p-side layer 13 inside the outer periphery. This makes it difficult to generate leakage current between the p-side layer 13 and the n-side layer 11 via the semiconductor debris, even if semiconductor debris adheres to the outer surface of the semiconductor structure 10. As shown in Figure 16, in the third embodiment, the width of the n-side electrode 50 in the second direction Y is equal to the width of the n-side opening 41 in the second direction Y, and the width of the p-side electrode 60 in the second direction Y is equal to the width of the p-side opening 42 in the second direction Y.

[0075] In the outer periphery of the semiconductor structure 10, no n-side opening 41 is formed in the second insulating film 40. Therefore, the third insulating film 70, which is arranged on the outer periphery of the semiconductor structure 10, is not required to have the same etching resistance as when forming the n-side opening 41 in the second insulating film 40. Accordingly, a film made of a different material from the first insulating film 30 can be selected for the third insulating film 70. For example, in the third embodiment, the third insulating film 70 can be a film with a lower light absorption rate to the light emitted by the active layer 12 than the first insulating film 30. By using, for example, a silicon oxide film as the third insulating film 70, light absorption in the third insulating film 70 can be reduced compared to when a silicon nitride film is used.

[0076] Furthermore, the third insulating film 70 can also be placed beneath the p-side electrode 60. As shown in Figure 16, the third insulating film 70 is placed on the p-side layer 13 between the p-side layer 13 and the p-side electrode 60, the translucent conductive layer 20 is placed on the third insulating film 70, and the p-side electrode 60 is placed on the translucent conductive layer 20. The translucent conductive layer 20 is in contact with the p-side layer 13 in areas where the first insulating film 30 and the third insulating film 70 are not placed, and the p-side electrode 60 is electrically connected to the p-side layer 13 via the translucent conductive layer 20. By placing the third insulating film 70 beneath the p-side electrode 60, the light emitted by the active layer 12 can be totally reflected at the interface between the p-side layer 13 and the third insulating film 70. This reduces the absorption of light at the p-side electrode 60. The thickness of the third insulating film 70 is preferably greater than the thickness of the second insulating film 40. The thickness of the third insulating film 70 is greater than the thickness of the second insulating film 40, which makes it easier for the light emitted by the active layer 12 to undergo total internal reflection at the interface between the p-side layer 13 and the third insulating film 70. For example, the thickness of the third insulating film 70 can be 50 nm or more and 1000 nm or less, and is preferably 200 nm or more and 400 nm or less.

[0077] As shown in Figure 17, after forming a plurality of first regions 11a on the semiconductor structure 10, and before forming the translucent conductive layer 20, a third insulating film 70 is formed on the outer periphery of the semiconductor structure 10 and in the region where the p-side electrode 60 is located. The third insulating film 70 is formed in a grid pattern, for example, in a top view, in the wafer state before it is separated into individual light-emitting elements.

[0078] After forming the third insulating film 70, the steps described in Figure 7 and later are carried out. The heat treatment of the semiconductor structure 10 to desorb hydrogen from the p-side layer 13 is performed after the formation of the third insulating film 70. As described above, the third insulating film 70 makes it difficult for hydrogen to desorb from the p-side layer 13 on the outer periphery of the semiconductor structure 10, and thus makes it difficult to reduce the electrical resistance of the p-side layer 13 on the outer periphery of the semiconductor structure 10.

[0079] The first insulating film 30 is formed after the third insulating film 70 is formed. If the heat treatment of the semiconductor structure 10 is performed after the formation of the third insulating film 70 and the first insulating film 30, it becomes more difficult to simultaneously reduce the electrical resistance of the p-side layer 13 on the outer periphery of the semiconductor structure 10 and the electrical resistance of the p-side layer 13 below the n-side electrode 50, thereby efficiently improving the reliability of the light-emitting element. If the heat treatment of the semiconductor structure 10 is performed after the formation of the third insulating film 70 but before the formation of the first insulating film 30, the region of the p-side layer 13 where the electrical resistance has not been reduced can be limited to the region where the third insulating film 70 is formed. As a result, the forward voltage of the light-emitting element can be lowered compared to the case where the heat treatment of the semiconductor structure 10 is performed after the formation of the third insulating film 70 and the first insulating film 30.

[0080] Embodiments of the present invention include the following methods for manufacturing a light-emitting element and a light-emitting element.

[0081] [Section 1] A semiconductor structure having an n-side layer, a p-side layer, and an active layer located between the n-side layer and the p-side layer, wherein the n-side layer is exposed from the active layer and the p-side layer and has a plurality of first regions arranged in a first direction when viewed from above, a step of preparing the semiconductor structure, The process involves forming a first insulating film on the p-side layer located between the plurality of first regions, A step of forming a second insulating film that continuously covers the first region, the p-side layer, and the first insulating film, A step of removing the second insulating film on the first region and the first insulating film to form an n-side opening in the second insulating film that is continuous in the first direction when viewed from above, and in which the first region and the first insulating film are exposed from the second insulating film, A step of forming an n-side electrode in the n-side opening that is in contact with the first region and the first insulating film, Equipped with, In a top view, the width of the n-side opening in the second direction perpendicular to the first direction is less than or equal to the width of the first insulating film in the second direction. A method for manufacturing a light-emitting element. [Section 2] The n-side opening has a first opening located on the first region and a second opening located on the first insulating film. In a top view, the width of the first opening in the second direction is greater than the width of the second opening in the second direction. The n-side electrode has a first portion located at the first opening and a second portion located at the second opening. The method for manufacturing a light-emitting element according to item 1, wherein, in a top view, the width of the first portion in the second direction is greater than the width of the second portion in the second direction. [Section 3] The method for manufacturing a light-emitting element according to item 2, wherein, in a top view, the width of the first portion of the n-side electrode in the second direction is greater than or equal to the width of the first opening of the n-side opening in the second direction, and less than or equal to the width of the first region in the second direction. [Section 4] A method for manufacturing a light-emitting element according to any one of the above items 1 to 3, wherein in the step of forming the n-side opening in the second insulating film, the second insulating film is removed under etching conditions in which the etching rate for the first insulating film is lower than the etching rate for the second insulating film. [Section 5] A method for manufacturing a light-emitting element according to any one of the above items 1 to 4, wherein the thickness of the first insulating film is greater than the thickness of the second insulating film. [Section 6] A method for manufacturing a light-emitting element according to any one of the above items 1 to 5, wherein, in a top view, the first insulating film continuously covers the outer edges of a plurality of the first regions. [Section 7] A method for manufacturing a light-emitting element according to any one of the above items 1 to 5, wherein, in a top view, the width of the first insulating film in the second direction is smaller than the width of the first region in the second direction. [Section 8] The first insulating film is a silicon nitride film, The method for manufacturing a light-emitting element according to any one of the above items 1 to 7, wherein the second insulating film is a silicon oxynitride film. [Section 9] The step of preparing the semiconductor structure includes forming a translucent conductive layer in the region of the p-side layer excluding the region between the first regions when viewed from above, A method for manufacturing a light-emitting element according to any one of items 1 to 8, further comprising the step of heat-treating the semiconductor structure after the step of forming the first insulating film. [Section 10] A semiconductor structure having an n-side layer, a p-side layer, and an active layer located between the n-side layer and the p-side layer, wherein the n-side layer is exposed from the active layer and the p-side layer and has a plurality of first regions arranged in a first direction when viewed from above, A first insulating film disposed on the p-side layer located between the plurality of first regions, A second insulating film disposed on the first region, the p-side layer, and the first insulating film, the second insulating film being continuous in the first direction when viewed from above, and having an n-side opening that exposes the first region and the first insulating film, An n-side electrode is provided in the n-side opening and is in contact with the first region and the first insulating film, Equipped with, In a top view, the width of the n-side opening in a second direction perpendicular to the first direction is less than or equal to the width of the first insulating film in the second direction. [Section 11] The n-side opening has a first opening located on the first region and a second opening located on the first insulating film. In a top view, the width of the first opening in the second direction is greater than the width of the second opening in the second direction. The n-side electrode has a first portion located at the first opening and a second portion located at the second opening. The light-emitting element according to item 10, wherein, in a top view, the width of the first portion in the second direction is greater than the width of the second portion in the second direction. [Section 12] The light-emitting element according to item 11, wherein, in a top view, the width of the first portion of the n-side electrode in the second direction is greater than or equal to the width of the first opening of the n-side opening in the second direction, and less than or equal to the width of the first region in the second direction. [Section 13] The light-emitting element according to any one of the above items 10 to 12, wherein the thickness of the first insulating film is greater than the thickness of the second insulating film. [Section 14] In a top view, the first insulating film continuously covers the outer edges of a plurality of the first regions, as described in any one of items 10 to 13 above. [Section 15] A light-emitting element according to any one of the above items 10 to 13, wherein, in a top view, the width of the first insulating film in the second direction is smaller than the width of the first region in the second direction. [Section 16] The first insulating film is a silicon nitride film, The light-emitting element according to any one of the above items 10 to 15, wherein the second insulating film is a silicon oxynitride film. [Section 17] The p-side layer further comprises a translucent conductive layer disposed on the p-side layer, In a top view, the light-transmitting conductive layer is positioned so as not to overlap with the first insulating film, as described in any one of items 10 to 16 above. [Explanation of symbols]

[0082] 1-3…Light-emitting element, 10…Semiconductor structure, 11…n-side layer, 11a…First region, 12…Active layer, 13…p-side layer, 20…Transparent conductive layer, 30…First insulating film, 40…Second insulating film, 41…n-side opening, 41a…First opening, 41b…Second opening, 42…p-side opening, 50…n-side electrode, 51…First part, 52…Second part, 60…p-side electrode, 70…Third insulating film, 100…Substrate

Claims

1. A semiconductor structure having an n-side layer, a p-side layer, and an active layer located between the n-side layer and the p-side layer, wherein the n-side layer is exposed from the active layer and the p-side layer and has a plurality of first regions arranged in a first direction when viewed from above, a step of preparing the semiconductor structure, The process involves forming a first insulating film on the p-side layer located between the plurality of first regions, A step of forming a second insulating film that continuously covers the first region, the p-side layer, and the first insulating film, The process involves removing the second insulating film on the first region and the first insulating film to form an n-side opening in the second insulating film that is continuous in the first direction when viewed from above, and in which the first region and the first insulating film are exposed from the second insulating film. A step of forming an n-side electrode in the n-side opening that is in contact with the first region and the first insulating film, Equipped with, In a top view, the width of the n-side opening in the second direction perpendicular to the first direction is less than or equal to the width of the first insulating film in the second direction. A method for manufacturing a light-emitting element.

2. The n-side opening has a first opening located on the first region and a second opening located on the first insulating film. In a top view, the width of the first opening in the second direction is greater than the width of the second opening in the second direction. The n-side electrode has a first portion located at the first opening and a second portion located at the second opening. The method for manufacturing a light-emitting element according to claim 1, wherein, in a top view, the width of the first portion in the second direction is greater than the width of the second portion in the second direction.

3. The method for manufacturing a light-emitting element according to claim 2, wherein, in a top view, the width of the first portion of the n-side electrode in the second direction is greater than or equal to the width of the first opening of the n-side opening in the second direction, and less than or equal to the width of the first region in the second direction.

4. A method for manufacturing a light-emitting element according to any one of claims 1 to 3, wherein in the step of forming the n-side opening in the second insulating film, the second insulating film is removed under etching conditions in which the etching rate for the first insulating film is lower than the etching rate for the second insulating film.

5. The method for manufacturing a light-emitting element according to any one of claims 1 to 3, wherein the thickness of the first insulating film is greater than the thickness of the second insulating film.

6. The method for manufacturing a light-emitting element according to claim 1, wherein, in a top view, the first insulating film continuously covers the outer edges of a plurality of the first regions.

7. The method for manufacturing a light-emitting element according to claim 1, wherein, in a top view, the width of the first insulating film in the second direction is smaller than the width of the first region in the second direction.

8. The first insulating film is a silicon nitride film, The method for manufacturing a light-emitting element according to any one of claims 1 to 3, 6, and 7, wherein the second insulating film is a silicon oxynitride film.

9. The step of preparing the semiconductor structure includes forming a translucent conductive layer in the region of the p-side layer excluding the region between the first regions when viewed from above, A method for manufacturing a light-emitting element according to any one of claims 1 to 3, 6, and 7, further comprising the step of heat-treating the semiconductor structure after the step of forming the first insulating film.

10. A semiconductor structure having an n-side layer, a p-side layer, and an active layer located between the n-side layer and the p-side layer, wherein the n-side layer is exposed from the active layer and the p-side layer and has a plurality of first regions arranged in a first direction when viewed from above, A first insulating film disposed on the p-side layer located between the plurality of first regions, A second insulating film disposed on the first region, the p-side layer, and the first insulating film, the second insulating film being continuous in the first direction when viewed from above, and having an n-side opening that exposes the first region and the first insulating film, An n-side electrode is arranged in the n-side opening and is in contact with the first region and the first insulating film, Equipped with, In a top view, the width of the n-side opening in a second direction perpendicular to the first direction is less than or equal to the width of the first insulating film in the second direction.

11. The n-side opening has a first opening located on the first region and a second opening located on the first insulating film. In a top view, the width of the first opening in the second direction is greater than the width of the second opening in the second direction. The n-side electrode has a first portion located at the first opening and a second portion located at the second opening. The light-emitting element according to claim 10, wherein, in a top view, the width of the first portion in the second direction is greater than the width of the second portion in the second direction.

12. The light-emitting element according to claim 11, wherein, in a top view, the width of the first portion of the n-side electrode in the second direction is greater than or equal to the width of the first opening of the n-side opening in the second direction, and less than or equal to the width of the first region in the second direction.

13. The light-emitting element according to any one of claims 10 to 12, wherein the thickness of the first insulating film is greater than the thickness of the second insulating film.

14. The light-emitting element according to claim 10, wherein, in a top view, the first insulating film continuously covers the outer edges of a plurality of the first regions.

15. The light-emitting element according to claim 10, wherein, in a top view, the width of the first insulating film in the second direction is smaller than the width of the first region in the second direction.

16. The first insulating film is a silicon nitride film, The light-emitting element according to any one of claims 10 to 12, 14, and 15, wherein the second insulating film is a silicon oxynitride film.

17. The p-side layer further comprises a translucent conductive layer disposed on the p-side layer, The light-emitting element according to any one of claims 10 to 12, 14, and 15, wherein, in a top view, the translucent conductive layer is positioned so as not to overlap with the first insulating film.

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