Light-emitting diode and manufacturing method therefor, and light-emitting device

Abstract

The present application relates to the technical field of semiconductor manufacturing, and discloses a light-emitting diode and a manufacturing method therefor, and a light-emitting device. The light-emitting diode comprises a base substrate, a first semiconductor layer, an active layer, and a second semiconductor layer; the top of the base substrate has a first area and a second area which are distributed along the substrate surface of the base substrate and are adjacent to each other, and the second area is distributed around the first area; a plurality of holes are formed in the part of the first semiconductor layer located in the second area, and the holes extend downwards to the base substrate; at least part of the hole section of each hole is formed as a chamfered hole section; the chamfered hole section gradually shrinks from bottom to top, so that a chamfered reflecting surface is formed on the interface between the inner side wall of the chamfered hole section and the hole; and the chamfered reflecting surface is at least distributed on a light receiving side of the chamfered hole section. The light-emitting diode provided by the present application has higher light-emitting efficiency.

Description

Light-emitting diode, manufacturing method thereof, and light-emitting device Technical Field

[0001] The present application relates to the field of semiconductor manufacturing technology, and more particularly to a light-emitting diode (LED), a method for manufacturing the same, and a light-emitting device. Background Art

[0002] A light-emitting diode (LED) is a semiconductor device that emits light by releasing energy when carriers recombine. LED chips have many advantages, including low power consumption, pure color, long life, small size, fast response time, energy saving and environmental protection. They are widely used in lighting, visible light communication, and luminous display scenarios.

[0003] Currently, the industry is fully engaged in the development of upright LED chip structures. However, existing upright LED chip structures still have some shortcomings. Specifically, the light extraction efficiency of LEDs still needs to be improved. Summary of the Invention

[0004] In view of this, in order to solve the above technical problems, the present application provides a light emitting diode, a method for manufacturing the same, and a light emitting device.

[0005] To achieve the above objectives, the present application provides a light emitting diode, which includes a substrate, a first semiconductor layer, an active layer and a second semiconductor layer.

[0006] The substrate has a first region and a second region disposed adjacent to each other along the substrate surface, with the second region surrounding the first region. A first semiconductor layer is formed on the substrate and continuously disposed in the first and second regions. An active layer is formed on the first semiconductor layer and disposed in the first region. A second semiconductor layer is formed on the active layer.

[0007] The portion of the first semiconductor layer located in the second region is provided with a plurality of openings, which extend downward to the substrate. At least some of the openings are chamfered sections, which taper gradually from bottom to top, forming a chamfered reflective surface at the interface between the inner sidewall of the chamfered section and the opening. The chamfered reflective surface is distributed at least on the light-receiving side of the chamfered section.

[0008] In order to solve the above technical problems, another technical solution adopted by the present application is to provide a method for preparing a light-emitting diode, the method for preparing a light-emitting diode comprising:

[0009] Forming a base substrate, a first semiconductor layer, an active layer, and a second semiconductor layer stacked in sequence, wherein the base substrate has a first region and a second region distributed along a surface of the base substrate and adjacent to each other, and the second region is distributed around the first region;

[0010] Performing a first etching process downward on the portion of the second semiconductor layer located in the second region until the first semiconductor layer is etched, so as to etch away portions of the second semiconductor layer and the active layer located in the second region;

[0011] A second etching process is performed on the portion of the first semiconductor layer located in the second area to form a plurality of openings, which extend to the substrate; at least part of the hole segments of the openings are formed as chamfered hole segments; the chamfered hole segments gradually shrink from bottom to top so that a chamfered reflective surface is formed at the interface between the inner side wall of the chamfered hole segment and the opening; the chamfered reflective surface is distributed at least on the light-receiving side of the chamfered hole segment.

[0012] In order to solve the above technical problem, another technical solution adopted in the present application is to provide a light-emitting device, which includes the above-mentioned light-emitting diode.

[0013] Beneficial Effects: Unlike the prior art, the present invention utilizes a chamfered reflective surface to reflect light from the first region, from the active layer, into the second region, reducing the angle between the reflected light and the thickness direction of the active layer to below the critical angle for total internal reflection. This allows the reflected light to exit from the second region on the side of the first semiconductor layer facing away from the substrate, thereby improving the light extraction efficiency of the LED. Furthermore, because the chamfered reflective surface is formed at the interface between the inner sidewall of the chamfered hole segment and the opening, it has a larger reflection area than a reflective surface parallel to the thickness direction of the first semiconductor layer, further contributing to improved light extraction efficiency of the LED. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] FIG1 is a schematic structural diagram of an embodiment of a light emitting diode of the present application;

[0015] FIG2 is a schematic cross-sectional view of the light emitting diode shown in FIG1 along line A1-A1;

[0016] FIG3 is a partial cross-sectional enlarged schematic diagram of the area where the opening is located in FIG1 ;

[0017] FIG4 is an enlarged schematic diagram of area A in FIG1 ;

[0018] FIG5 is a schematic diagram showing the position of the annular distribution area in the light emitting diode shown in FIG1;

[0019] 6 to 12 are cross-sectional views of the light emitting diode of the present application at various stages of the manufacturing process;

[0020] FIG13 is a schematic structural diagram of another embodiment of a light emitting diode of the present application;

[0021] FIG14 is an enlarged schematic diagram of area B in FIG13;

[0022] FIG15 is a schematic structural diagram of another embodiment of a light emitting diode of the present application;

[0023] FIG16 is an enlarged schematic diagram of area C in FIG15 ;

[0024] FIG17 is a partial top view of the light emitting diode experimental group of the present application after being processed in step S11;

[0025] FIG18 is a partial cross-sectional enlarged schematic diagram of the opening area of ​​an independent light-emitting diode prepared in the light-emitting diode experimental group of the present application;

[0026] FIG19 is a partial top view of the light emitting diode control group of the present application after being processed in step S21;

[0027] FIG20 is a partial enlarged cross-sectional view of the region where the opening of an independent light-emitting diode prepared in the light-emitting diode control group of the present application is located.

[0028] 10a, 10b, 10c, 10d, 10e - light-emitting diode; 100 - substrate; 200 - first semiconductor layer; 300 - active layer; 400 - second semiconductor layer; 500 - reflective layer; 271 - first electrode; 272 - second electrode; 20 - etching protection layer; 21 - etching positioning hole; 30 - cutting street; 31 - planar reflective surface;

[0029] 201 - opening; 202 - chamfered hole section; 203 - chamfered reflecting surface; α1 - first inclination angle; α2 - second inclination angle. DETAILED DESCRIPTION

[0030] To enable those skilled in the art to better understand the technical solutions of this application, the present application is further described below in conjunction with the accompanying drawings and specific embodiments. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative work are within the scope of protection of this application.

[0031] 1 to 4 , the light emitting diode 10 a of the present application includes a base substrate 100 , a first semiconductor layer 200 , an active layer 300 and a second semiconductor layer 400 .

[0032] The upper portion of the base substrate 100 has a first region (not labeled) and a second region (not labeled) distributed along the surface of the base substrate 100 and adjacent to each other, with the second region surrounding the first region. A first semiconductor layer 200 is formed on the base substrate 100 and continuously distributed across the first and second regions. An active layer 300 is formed on the first semiconductor layer 200 and distributed across the first region. A second semiconductor layer 400 is formed on the active layer 300.

[0033] The portion of the first semiconductor layer 200 located in the second region is provided with a plurality of openings 201, which extend downward to the base substrate 100. At least a portion of the openings 201 is formed as chamfered hole sections 202. The chamfered hole sections 202 gradually taper upward, forming chamfered reflective surfaces 203 at the interface between the inner sidewalls of the chamfered hole sections 202 and the openings 201. The chamfered reflective surfaces 203 are distributed at least on the light-receiving side of the chamfered hole sections 202.

[0034] In this manner, the chamfered reflective surface 203 can reflect light from the first region, through the active layer 300, into the second region, reducing the angle between the reflected light and the thickness direction of the active layer 300 to below the critical angle for total internal reflection. This allows the reflected light to exit from the second region on the side of the first semiconductor layer 200 facing away from the substrate 100, thereby improving the light extraction efficiency of the light-emitting diode 10a. Furthermore, because the chamfered reflective surface 203 is formed at the interface between the inner sidewall of the chamfered hole segment 202 and the opening 201, the chamfered reflective surface 203 has a larger reflection area than a reflective surface parallel to the thickness direction of the first semiconductor layer 200, thereby further improving the light extraction efficiency of the light-emitting diode 10a.

[0035] Optionally, the chamfered reflective surface 203 extends downward to the base substrate 100. This can greatly increase the reflective area of ​​the chamfered reflective surface 203, which is more conducive to improving the light extraction efficiency of the light emitting diode 10a.

[0036] For example, but not limitation, referring to FIG3-FIG4 in conjunction with FIG1-FIG2, the depth of the opening 201 along the thickness direction of the first semiconductor layer 200 is 6um to 12um (for example, 6um, 8um, 12um). In addition, the cross-sectional area of ​​the end of the chamfered hole section 202 facing away from the base substrate 100 is 4um. 2 ~12um 2 (For example, 4um 2 、8um 2 、12um 2 ).

[0037] By adopting the above-mentioned method, the thickness of the first semiconductor layer 200 can be prevented from being too thick, and the chamfered reflective surface 203 can have an appropriate reflective area.

[0038] In one example, as shown in FIG3 , all of the hole segments of the opening 201 are chamfered hole segments 202. In another example (not shown), another portion of the hole segments of the opening are formed as connecting hole segments that are away from the substrate and connect with the chamfered hole segments. The difference in cross-sectional area between the connecting hole segments and the cross-sectional area of ​​the end of the chamfered hole segment 202 facing away from the substrate is less than 1 μm. 2 .

[0039] Optionally, the line-plane angle formed between a tangent plane (not shown) corresponding to a point on the chamfered reflective surface 203 and the thickness direction of the first semiconductor layer 200 is 30 degrees to 60 degrees (for example, 30 degrees, 45 degrees, or 60 degrees). This allows light reflected from the chamfered reflective surface 203 to be emitted from the side of the first semiconductor layer 200 facing away from the base substrate 100. Preferably, the line-plane angle formed between a tangent plane corresponding to a point on the chamfered reflective surface 203 and the thickness direction of the first semiconductor layer 200 is 45 degrees to 60 degrees (for example, 45 degrees, 50 degrees, or 60 degrees).

[0040] 3 , the chamfered reflective surface 203 has a first tilt angle α1 relative to a plane perpendicular to the thickness direction of the first semiconductor layer 200 , and the first tilt angle α1 is 30 to 45 degrees (eg, 30, 40, or 45 degrees).

[0041] Furthermore, referring to Figures 3 and 4 in conjunction with Figures 1 and 2 , the light-emitting diode 10a includes a reflective layer 500, which is formed on the side of the base substrate 100 facing away from the first semiconductor layer 200. Thus, the reflective layer 500 can reflect light emitted from the active layer 300 toward the side of the base substrate 100, allowing a portion of the reflected light to pass through the active layer 300 and be emitted from the side of the active layer 300 facing away from the base substrate 100. Furthermore, a portion of the light reflected by the reflective layer 500 toward the chamfered reflective surface 203 can, after reflection from the chamfered reflective surface 203, be emitted from the second region and from the side of the first semiconductor layer 200 facing away from the base substrate 100.

[0042] 4 , when viewed from above the LED 10a, the opening 201 facing away from the first region communicates with the edge of the first semiconductor layer 200. By way of example and not limitation, when viewed from above the LED 10a, the opening 201 is trapezoidal.

[0043] In another example (not shown), the opening is spaced from the edge of the first semiconductor layer when viewed from above the LED. By way of example and not limitation, the opening is circular, hexagonal, rhombus-shaped, or other regular or irregular shapes when viewed from above the LED.

[0044] Preferably, referring to FIG4 in conjunction with FIG1-FIG2, the chamfered reflective surface 203 is bent or curved around the thickness direction of the first semiconductor layer 200. This can further increase the reflective area of ​​the chamfered reflective surface 203 within a limited space, thereby further improving the light extraction efficiency of the light-emitting diode 10a.

[0045] Alternatively, referring to FIG. 5 in conjunction with FIG. 1-4 , the dotted line in FIG. 5 represents the location of the annular distribution region within the LED 10a. Multiple openings 201 are distributed around the first region. This allows these openings 201 to better reflect light entering the second region from the first region, so that the reflected light exits from the side of the first semiconductor layer 200 facing away from the substrate 100, reducing or preventing light from escaping from the periphery of the second region.

[0046] To reduce or prevent light from escaping from the periphery of the second region, in one example, preferably, at least some of the openings 201 are sequentially distributed around the first region to form an annular distribution area surrounding the first region. Adjacent openings 201 in the annular distribution area are interconnected. Of course, in other examples, adjacent openings 201 in the annular distribution area may also be spaced apart.

[0047] By adopting the above method, the light emitted by the light emitting diode can be converged and the brightness can be more concentrated.

[0048] In addition, the light emitting diode 10 a may further include a first electrode 271 and a second electrode 272 . The first electrode 271 is formed on the first semiconductor layer 200 and located in the second region. The second electrode 272 is formed on the second semiconductor layer 400 .

[0049] It should be noted that the features of the first electrode 271 and the second electrode 272 can be found in the relevant description of the first electrode and the second electrode in Chinese Patent Application Publication No. CN113707779A, and will not be repeated here. In addition, the disclosure of Chinese Patent Application Publication No. CN113707779A that does not conflict with the technical features of the present application is incorporated herein by reference and may be used as the technical features disclosed in the present application.

[0050] In one example, referring to FIG13 and FIG14 in comparison with FIG1 and FIG4 , a light-emitting diode 10b is provided. The parts of light-emitting diode 10b that are identical to those of light-emitting diode 10a are not described in detail. The difference is that, when viewed from above, opening 201 of light-emitting diode 10b has a convex edge on the light-receiving side. For example, opening 201 is semicircular.

[0051] In the above manner, the chamfered reflective surface (not labeled in Figures 13 and 14) extends along the thickness direction of the first semiconductor layer 200 to form a convex surface that protrudes toward the first region, so that the chamfered reflective surface becomes a convex mirror. As a result, the light reflected by the chamfered reflective surface can be dispersed, achieving a certain light uniformity effect. It should be understood that the so-called "convex surface" herein can be a curved surface or a combination of multiple flat surfaces.

[0052] In another example, referring to FIG15-FIG16 in comparison with FIG1 and FIG4, a light-emitting diode 10c is provided, wherein the parts of the light-emitting diode 10c that are the same as the above-mentioned light-emitting diode 10a are not repeated, and the difference is that, when viewed from above the light-emitting diode 10c, the opening 201 is a triangle.

[0053] Of course, in other examples (not shown), when viewed from above the light emitting diode, the opening may have other regular or irregular shapes.

[0054] The following describes a method for manufacturing a light emitting diode 10a of the present application in conjunction with Figures 6 to 12. The method for manufacturing the light emitting diode 10a includes the following steps S110 to S130.

[0055] Step S110: forming a reflective layer, a base substrate, a first semiconductor layer, an active layer and a second semiconductor layer stacked in sequence.

[0056] 6 , the base substrate 100 may be a transparent substrate, a non-transparent substrate, or a semi-transparent substrate. For example, the base substrate 100 may be any one of a sapphire flat substrate, a sapphire patterned substrate, a silicon substrate, a silicon carbide substrate, a gallium nitride substrate, and a glass substrate.

[0057] The first semiconductor layer 200, grown on the substrate 100, can be a gallium nitride semiconductor layer doped with n-type impurities, such as Si. In some embodiments, a buffer layer is disposed between the first semiconductor layer 200 and the substrate 100. In other embodiments, the first semiconductor layer 200 can be bonded to the substrate 100 via an adhesive layer (not shown).

[0058] Active layer 300 can have a single quantum well structure or a multiple quantum well structure. The composition and thickness of the well layers within active layer 300 determine the wavelength of light generated. In particular, by adjusting the composition of the well layers, active layer 300 can be configured to generate different colors of light, such as ultraviolet light, blue light, and green light.

[0059] The second semiconductor layer 400 may be a gallium nitride semiconductor layer doped with p-type impurities, such as Mg. Although the first semiconductor layer 200 and the second semiconductor layer 400 may each be a single layer, the present invention is not limited thereto and may also be a multi-layer structure and may also include a superlattice layer. The first semiconductor layer 200, the active layer 300, and the second semiconductor layer 400 may be formed on the base substrate 100 using methods such as metal organic chemical vapor deposition (MOCVD) or molecular beam epitaxy (MBE). In addition, when the first semiconductor layer 200 is doped with p-type impurities, the second semiconductor layer 400 is doped with n-type impurities.

[0060] It should be understood that in some other examples, the reflective layer 500 may not be formed.

[0061] Step S120: etching away portions of the second semiconductor layer and the active layer located in the second region.

[0062] As shown in FIG. 7 , the upper portion of the base substrate 100 has a first region and a second region distributed along the surface of the base substrate 100 and adjacent to each other, and the second region surrounds the first region.

[0063] A first etching process is performed downward on the portion of the second semiconductor layer 400 located in the second region until the etching reaches the first semiconductor layer 200 , so as to etch away portions of both the second semiconductor layer 400 and the active layer 300 located in the second region.

[0064] Step S130: forming an opening and a chamfered reflective surface.

[0065] A second etching process is performed on the portion of the first semiconductor layer located in the second region to form a plurality of openings extending to the substrate. At least a portion of the openings are formed as chamfered sections. The chamfered sections taper upwards, forming a chamfered reflective surface at the interface between the inner sidewall of the chamfered section and the opening. The chamfered reflective surface is distributed at least on the light-receiving side of the chamfered section.

[0066] Optionally, in one example, step S130 specifically includes steps S131 to S132.

[0067] Step S131 : performing dry etching on the portion of the first semiconductor layer located in the second region to form a plurality of openings.

[0068] The dry etching method includes but is not limited to plasma etching. Plasma etching includes but is not limited to etching by yellow light to form a plurality of openings. The openings extend to the substrate.

[0069] Step S132: wet-etching the sidewall of at least a portion of the opening so that a chamfered reflective surface is formed at the interface between the inner sidewall of at least a portion of the opening and the opening.

[0070] Wet etching is performed on at least a portion of the sidewall of the opening to form at least a portion of the opening into a chamfered hole segment. The chamfered hole segment gradually decreases from bottom to top, so that a chamfered reflective surface is formed at the interface between the inner sidewall of the chamfered hole segment and the opening. The chamfered reflective surface is distributed at least on the light-receiving side of the chamfered hole segment.

[0071] Compared to dry etching, wet etching can result in the etched chamfered reflective surface having a smaller inclination angle relative to a plane perpendicular to the thickness direction of the first semiconductor layer. This facilitates the chamfered reflective surface to reflect incident light toward the side of the first semiconductor layer located in the second region and facing away from the substrate. Wet etching is not limited to etching using a mixed acid, wherein the mixed acid includes a mixture of sulfuric acid and phosphoric acid in a volume ratio of 3:1. The temperature of the mixed acid is 250°C to 300°C (e.g., 250°C, 270°C, or 300°C).

[0072] In the above manner, the chamfered reflective surface can be formed by wet etching, which is conducive to forming a larger angle between the chamfered reflective surface and the thickness direction of the first semiconductor layer.

[0073] Optionally, in one example, before step S131, step S101 is included.

[0074] Step S101 : forming an etching protection layer on a portion of the first semiconductor layer located in the second region and on the second semiconductor layer.

[0075] As shown in FIG8 , the material of the etching protection layer 20 includes but is not limited to SiO 2 . The thickness of the etching protection layer 20 includes but is not limited to 2000 angstroms to 3000 angstroms (eg, 2000 angstroms, 2359 angstroms, 2500 angstroms, 3000 angstroms).

[0076] Step S131 specifically includes: performing dry etching on the portion of the etching protection layer located in the second area to form an etching positioning hole, and the etching positioning hole extends through the first semiconductor layer to the substrate; wherein the opening is the hole section remaining in the etching positioning hole after removing the hole section located in the etching protection layer.

[0077] As shown in Figure 9, the etching positioning hole 21 extends through the first semiconductor layer 200 to the base substrate 100. The opening 201 is the hole section remaining in the etching positioning hole 21 after removing the hole section located in the etching protection layer 20.

[0078] Step S132 specifically includes: wet etching the sidewall of at least a portion of the opening by etching the positioning hole, so that the inner sidewall of at least a portion of the opening and the interface between the opening form a chamfered reflective surface.

[0079] As shown in FIG10 , the sidewall of at least a portion of the opening 201 is wet-etched by etching the positioning hole 21 , so that a chamfered reflective surface 203 is formed at the interface between the inner sidewall of at least a portion of the opening 201 and the opening 201 .

[0080] Furthermore, after step S132 , steps S140 to S150 are included.

[0081] S140: stripping the etching protection layer to expose the portion of the first semiconductor layer located in the second region and the second semiconductor layer.

[0082] 10 and refer to FIG. 11 . In FIG. 11 , the etching protection layer 20 is stripped off.

[0083] Step S150: forming a first electrode on the second region of the first semiconductor layer, and forming a second electrode on the second semiconductor layer.

[0084] As shown in FIG. 12 , a first electrode 271 is formed in the second region of the first semiconductor layer 200 , and a second electrode 272 is formed on the second semiconductor layer 400 .

[0085] For the features of the first electrode 271 and the second electrode 272, please refer to the relevant description of the first electrode and the second electrode in the Chinese patent application with publication number CN113707779A, which will not be repeated here. In addition, the disclosure of the Chinese patent application with publication number CN113707779A that does not conflict with the technical features of the present application is incorporated herein by reference and can be used as the technical features disclosed in the present application.

[0086] Hereinafter, the beneficial effects of the light emitting diode 10a of the present application will be described through comparative experiments.

[0087] Experimental group

[0088] Step S11: preparing a plurality of light emitting diodes that share a common substrate and are distributed in multiple rows and columns.

[0089] Specifically, referring to Figures 17 and 18, a plurality of light-emitting diodes 10d having a common substrate and distributed in multiple rows and columns are prepared through the above-mentioned steps S110 to S150. The parts of the light-emitting diode 10d that are the same as the above-mentioned light-emitting diode 10a are not repeated here. The further limitation is that, when viewed from above the light-emitting diode 10d, the opening 201 is circular. The angle between the tangent plane corresponding to the point on the chamfered reflective surface 203 and the thickness direction of the first semiconductor layer 200 is 50 degrees, that is, the first inclination angle α1 of the chamfered reflective surface 203 relative to the plane perpendicular to the thickness direction of the first semiconductor layer 200 is 30 degrees. The cross-sectional area of ​​the end of the chamfered hole section 202 facing away from the substrate 100 is 8um.2 , and the depth of the chamfered hole section 202 along the thickness direction of the first semiconductor layer 200 is 9 μm.

[0090] Step S12: using laser to cut the portion of the substrate corresponding to the area between adjacent light emitting diodes to form a cutting street.

[0091] The dotted lines in FIG17 represent the positions of the cutting paths.

[0092] Step S13 : splitting the base substrate along the cutting lines to separate the base substrate between adjacent light-emitting diodes, so that the light-emitting diodes sharing the base substrate become a plurality of independent light-emitting diodes.

[0093] Specifically, the base substrate may be split by aligning the cleavage knife with the cleavage streets, so that a plurality of light-emitting diodes sharing the base substrate become a plurality of independent light-emitting diodes.

[0094] Alternatively, in one embodiment, upon completion of step S12, the openings 201 located near the scribe line in the LEDs 10d on either side of the scribe line are spaced apart on both sides of the scribe line, as shown in FIG17 . Thus, after the substrate 100 is cleaved, the openings 201 located on either side of the scribe line are allocated to different LEDs 10d.

[0095] Alternatively, in another embodiment (not shown), upon completion of step S12, the openings of the LEDs located on either side of the scribe line, adjacent to the scribe line, are joined at the scribe line to form a single, integrated hole. Thus, after the substrate is cleaved, the hole is cut so that the two openings on either side of the scribe line are each assigned to a different LED.

[0096] control group

[0097] Step S21: preparing a plurality of light emitting diodes that share a common substrate and are distributed in multiple rows and columns.

[0098] Specifically, referring to FIG. 19 , after step S21 is executed, light-emitting diodes 10 e having a common substrate and arranged in multiple rows and columns are prepared. The same parts as step S11 are not repeated here. The difference is that the light-emitting diodes 10 e formed in step S21 do not have the openings 201 and chamfered reflective surfaces 203 as in the light-emitting diodes 10 d described above.

[0099] Step S22: using laser to cut the portion of the substrate corresponding to the area between adjacent light emitting diodes to form a cutting street.

[0100] 19-20 , the cutting path 30 gradually shrinks as it approaches the first semiconductor layer 200 along the thickness direction of the base substrate 100 , so as to form a planar reflective surface 31 on both sidewalls of the cutting path 30 that is inclined relative to a plane perpendicular to the thickness direction of the base substrate 100 .

[0101] The planar reflective surface 31 has a second tilt angle α2 relative to a plane perpendicular to the thickness direction of the base substrate 100 , and the second tilt angle α2 is 50 degrees.

[0102] Step S23 : splitting the base substrate along the cutting lines to split the base substrate 100 between adjacent light-emitting diodes, so that the light-emitting diodes sharing the base substrate become a plurality of independent light-emitting diodes.

[0103] The light-emitting diodes 10d obtained from the experimental group and the light-emitting diodes 10e obtained from the control group were tested, and the data shown in Table 1 were obtained.

[0104] Table 1: Data comparison table.

[0105] Item Test Sample Number Average Voltage Starting Voltage Normalized Brightness Experimental Group 5 2.765V 2.267V 4 2.97mW Control Group 5 2.770V 2.2748V 4 3.19mW Increment / 0.005V 0.0078V 0.22mW Percentage of Increment / 0.18% 0.34% 0.51%

[0106] As shown in Table 1 above, the normalized brightness of the light-emitting diode 10d in the experimental group is increased by about 0.51% compared to the normalized brightness of the light-emitting diode 10e in the control group.

[0107] The above is only an implementation method of the present application and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the description and drawings of this application, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A light emitting diode, characterized in that: The light emitting diode comprises: A base substrate, wherein the base substrate has a first region and a second region distributed along a surface of the base substrate and adjacent to each other, and the second region is distributed around the first region; A first semiconductor layer is formed on the substrate and is continuously distributed in the first region and the second region; An active layer formed on the first semiconductor layer and distributed in the first region; a second semiconductor layer formed on the active layer; Among them, the portion of the first semiconductor layer located in the second area is provided with a plurality of openings, and the openings extend downward to the substrate; at least part of the hole sections of the openings are formed as chamfered hole sections; the chamfered hole sections gradually shrink from bottom to top, so that a chamfered reflective surface is formed at the interface between the inner side wall of the chamfered hole section and the opening; the chamfered reflective surface is distributed at least on the light-receiving side of the chamfered hole section.

2. The light emitting diode according to claim 1, characterized in that: The chamfered reflective surface extends downward to the base substrate.

3. The light emitting diode according to claim 1, characterized in that: The line-plane angle formed by the tangent plane corresponding to the point on the chamfered reflective surface and the thickness direction of the first semiconductor layer is 30 degrees to 60 degrees.

4. The light emitting diode according to claim 1, characterized in that: The light emitting diode comprises a reflective layer, and the reflective layer is formed on a side of the substrate facing away from the first semiconductor layer.

5. The light emitting diode according to claim 1, characterized in that: When viewed from above the light-emitting diode, the side of the opening facing away from the first region is connected to the edge of the first semiconductor layer; Alternatively, when viewed from above the light-emitting diode, the opening is spaced apart from an edge of the first semiconductor layer.

6. The light emitting diode according to claim 1, characterized in that: The chamfered reflective surface extends in a bent or curved manner around the thickness direction of the first semiconductor layer.

7. The light emitting diode according to claim 1, characterized in that: A plurality of the openings are distributed around the first region.

8. The light emitting diode according to claim 7, characterized in that: At least part of the openings are sequentially distributed around the first area to form an annular distribution area surrounding the first area; Wherein, the adjacent openings in the annular distribution area are connected to each other; or the adjacent openings in the annular distribution area are arranged at intervals.

9. The light emitting diode according to claim 1, characterized in that: The depth of the opening along the thickness direction of the first semiconductor layer is 6um-12um.

10. The light emitting diode according to claim 1, characterized in that: The cross-sectional area of ​​the end of the chamfered hole section away from the substrate is 4um 2~ 12um 2 ; The other part of the hole segment of the opening is formed as a connecting hole segment away from the substrate and connected to the chamfered hole segment, and the difference between the cross-sectional area of ​​the connecting hole segment and the cross-sectional area of ​​the end of the chamfered hole segment away from the substrate is less than 1um. 2 Alternatively, all hole sections of the opening are the chamfered hole sections.

11. A method for preparing a light emitting diode, characterized in that: The preparation method comprises: Forming a base substrate, a first semiconductor layer, an active layer, and a second semiconductor layer stacked in sequence, wherein the base substrate has a first region and a second region distributed and adjacent to each other along the surface of the base substrate, and the second region is distributed around the first region; Performing a first etching process downward on the portion of the second semiconductor layer located in the second region until etching reaches the first semiconductor layer, so as to etch away the portions of the second semiconductor layer and the active layer located in the second region; A second etching process is performed on the portion of the first semiconductor layer located in the second area to form a plurality of openings, wherein the openings extend to the substrate; at least part of the hole segments of the openings are formed as chamfered hole segments; the chamfered hole segments gradually shrink from bottom to top so that a chamfered reflective surface is formed at the interface between the inner side wall of the chamfered hole segment and the opening; the chamfered reflective surface is distributed at least on the light-receiving side of the chamfered hole segment.

12. The preparation method according to claim 11, characterized in that: The step of performing a second etching process on the portion of the first semiconductor layer located in the second region comprises: Performing dry etching on a portion of the first semiconductor layer located in the second region to form a plurality of openings, wherein the openings extend to the substrate; Wet etching is performed on the side wall of at least a portion of the opening so that at least a portion of the opening is formed into a chamfered hole segment; the chamfered hole segment gradually shrinks from bottom to top so that a chamfered reflective surface is formed at the interface between the inner side wall of the chamfered hole segment and the opening; the chamfered reflective surface is distributed at least on the light-receiving side of the chamfered hole segment.

13. The preparation method according to claim 12, characterized in that: Before the step of dry etching the portion of the first semiconductor layer located in the second region, the method comprises: forming an etching protection layer on a portion of the first semiconductor layer located in the second region and on the second semiconductor layer; The step of performing dry etching on the portion of the first semiconductor layer located in the second region comprises: Dry etching is performed on the portion of the etching protection layer located in the second area to form an etching positioning hole, and the etching positioning hole extends through the first semiconductor layer to the substrate; wherein the opening is a hole section in the etching positioning hole located below the etching protection layer.

14. The preparation method according to claim 12, characterized in that: The dry etching includes plasma etching.

15. A light emitting device, characterized in that: The light emitting device comprises the light emitting diode according to any one of claims 1 to 10.

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