Light-emitting diode and light-emitting diode preparation method

Abstract

The invention provides a light emitting diode and a light emitting diode preparation method. The light-emitting diode comprises a substrate, an epitaxial structure, a first electrode structure, a reflecting layer and a second electrode structure, the epitaxial structure is located on the substrate, the epitaxial structure is divided into a first epitaxial structure and a second epitaxial structure by an isolation groove, the ratio of the surface area sum of the first epitaxial structure and the second epitaxial structure to the surface area of the substrate is 65-70%, and each epitaxial structure comprises a first semiconductor layer, an active layer and a second semiconductor layer which are stacked in sequence; the first epitaxial structure is provided with a first groove with the bottom located in the first semiconductor layer, and the second epitaxial structure is provided with a second groove with the bottom located in the first semiconductor layer; the second electrode is located in the first groove, and the fifth electrode is located in the second groove; the reflecting layer covers the epitaxial structure; the seventh electrode is connected with the first electrode and the third electrode, the eighth electrode is connected with the second electrode, the fourth electrode and the sixth electrode, and the ninth electrode is connected with the fifth electrode.

Description

Technical Field

[0001] This disclosure relates to the field of light-emitting devices, and in particular to a light-emitting diode and a method for fabricating a light-emitting diode. Background Technology

[0002] Light-emitting diodes (LEDs) are semiconductor devices that emit light. They have advantages such as energy saving, high brightness, high durability, long lifespan, and lightweight, and have been widely used in both backlight displays and direct-view displays.

[0003] The related technology provides a light-emitting diode, the structure of which includes an epitaxial structure, a reflective layer and an electrode structure, the reflective layer covering the epitaxial structure, and the electrode structure passing through the reflective layer and connected to the epitaxial structure.

[0004] Among the aforementioned light-emitting diodes (LEDs), improving their luminous efficacy is a major focus of current research. Summary of the Invention

[0005] This disclosure provides a light-emitting diode (LED) and a method for manufacturing an LED, which can significantly improve the luminous efficacy of the LED. The technical solution is as follows:

[0006] On one hand, a light-emitting diode (LED) is provided, the LED comprising:

[0007] Substrate, epitaxial structure, first electrode structure, reflective layer, and second electrode structure;

[0008] The epitaxial structure is located on the substrate. The epitaxial structure has an isolation trench and is divided into a first epitaxial structure and a second epitaxial structure by the isolation trench. The sum of the surface areas of the first epitaxial structure and the second epitaxial structure is 65-70% of the surface area of ​​the substrate. Both the first epitaxial structure and the second epitaxial structure include a first semiconductor layer, an active layer, and a second semiconductor layer stacked sequentially. The first epitaxial structure has a first groove with its bottom located on the first semiconductor layer, and the second epitaxial structure has a second groove with its bottom located on the first semiconductor layer.

[0009] The first electrode structure includes a first electrode, a second electrode, a third electrode, a fourth electrode, a fifth electrode, and a sixth electrode. The second electrode is located in the first groove, and the fifth electrode is located in the second groove. The first electrode and the third electrode are located on the second semiconductor layer on both sides of the first groove, and the fourth electrode and the sixth electrode are located on the second semiconductor layer on both sides of the second groove.

[0010] The reflective layer covers the epitaxial structure and the first electrode structure;

[0011] The second electrode structure includes a seventh electrode, an eighth electrode, and a ninth electrode located on the reflective layer. The seventh electrode passes through the reflective layer and is electrically connected to the first electrode and the third electrode, respectively. One side of the eighth electrode passes through the reflective layer and is electrically connected to the second electrode. The other side of the eighth electrode passes through the reflective layer and is electrically connected to the fourth electrode and the sixth electrode, respectively. The ninth electrode passes through the reflective layer and is electrically connected to the fifth electrode.

[0012] Optionally, the sum of the surface areas of the first epitaxial structure and the second epitaxial structure is 47,000–48,000 μm. 2 .

[0013] Optionally, the distance between the edges of the projections of the first epitaxial structure and the second epitaxial structure onto the substrate surface and the edge of the substrate is 6 to 8 μm.

[0014] Optionally, the seventh electrode has a U-shaped structure, with the two arms of the U-shaped structure respectively connected to the first electrode and the third electrode.

[0015] Optionally, the eighth electrode includes a first part and a second part. The first part is strip-shaped, with one end of the first part connected to the second electrode and the other end of the first part connected to the second part. The second part is annular, with the fourth electrode and the sixth electrode connected to the two sides of the annular shape, respectively. The ninth electrode is located within the annular shape.

[0016] Optionally, the ninth electrode is a rounded rectangle, and the rounded rectangle is similar in shape to the inner ring of the ring in the eighth electrode.

[0017] Optionally, the distance between the second electrode and the first electrode is equal to the distance between the second electrode and the third electrode, and the distance between the fifth electrode and the fourth electrode is equal to the distance between the fifth electrode and the sixth electrode.

[0018] Optionally, the light-emitting diode further includes a current blocking layer, a transparent conductive layer, a passivation layer, and an electrode pad structure;

[0019] The current blocking layer and the transparent conductive layer are sequentially located between the epitaxial structure and the reflective layer;

[0020] The current blocking layer includes a first current blocking layer and a second current blocking layer, wherein the first current blocking layer and the second current blocking layer are respectively located on the first epitaxial structure and the second epitaxial structure;

[0021] The transparent conductive layer includes a first transparent conductive layer and a second transparent conductive layer, the first transparent conductive layer and the second transparent conductive layer respectively cover the first current blocking layer and the second current blocking layer, and are respectively connected to the first epitaxial structure and the second epitaxial structure;

[0022] The passivation layer covers the reflective layer and the second electrode structure;

[0023] The electrode pad structure includes a first electrode pad and a second electrode pad. The first electrode pad passes through the passivation layer and is connected to the seventh electrode, and the second electrode pad passes through the passivation layer and is connected to the ninth electrode.

[0024] On the other hand, a method for fabricating a light-emitting diode includes:

[0025] An epitaxial structure is fabricated on a substrate. The epitaxial structure has an isolation trench and is divided into a first epitaxial structure and a second epitaxial structure by the isolation trench. The sum of the surface areas of the first epitaxial structure and the second epitaxial structure is 65-70% of the surface area of ​​the substrate. Both the first epitaxial structure and the second epitaxial structure include a first semiconductor layer, an active layer, and a second semiconductor layer stacked sequentially. The first epitaxial structure has a first groove with its bottom located in the first semiconductor layer, and the second epitaxial structure has a second groove with its bottom located in the first semiconductor layer.

[0026] A first electrode structure is fabricated, comprising a first electrode, a second electrode, a third electrode, a fourth electrode, a fifth electrode, and a sixth electrode. The second electrode is located in the first groove, and the fourth electrode is located in the second groove. The first electrode and the third electrode are located on the second semiconductor layer on both sides of the first groove, and the third electrode and the fifth electrode are located on the second semiconductor layer on both sides of the second groove.

[0027] A reflective layer is fabricated, which covers the epitaxial structure and the first electrode structure;

[0028] A second electrode structure is fabricated, comprising a seventh electrode, an eighth electrode, and a ninth electrode located on the reflective layer. The seventh electrode passes through the reflective layer and is electrically connected to the first electrode and the third electrode, respectively. One side of the eighth electrode passes through the reflective layer and is electrically connected to the second electrode, and the other side of the eighth electrode passes through the reflective layer and is electrically connected to the fourth electrode and the sixth electrode, respectively. The ninth electrode passes through the reflective layer and is electrically connected to the fifth electrode.

[0029] Optionally, the sum of the surface areas of the first epitaxial structure and the second epitaxial structure is 47,000–48,000 μm.2 .

[0030] The beneficial effects of the technical solutions provided in this disclosure are:

[0031] In this embodiment, the epitaxial structure is divided into a first epitaxial structure and a second epitaxial structure by an isolation trench. The ratio of the sum of the surface areas of the first and second epitaxial structures to the surface area of ​​the substrate is 65-70%. Under the premise of the same operating current, changing the area of ​​the light-emitting region will affect the luminous efficiency of the light-emitting diode chip. For LEDs with low operating current, appropriately reducing their light-emitting area can increase the current density of the LED chip, improve the internal quantum efficiency, and achieve the effect of improving brightness. Therefore, the ratio of the sum of the surface areas of the first and second epitaxial structures to the surface area of ​​the substrate is 65-70%, which is relatively high compared to related... In this technology, the surface area ratio of the epitaxial structure to the substrate is 86.7%, which improves the brightness of the light-emitting diode. Both the first epitaxial structure and the second epitaxial structure include a first semiconductor layer, an active layer, and a second semiconductor layer stacked sequentially. The first epitaxial structure has a first groove with its bottom located on the first semiconductor layer, and the second epitaxial structure has a second groove with its bottom located on the first semiconductor layer. In this embodiment, the first groove, the second groove, and the isolation trench ensure that the area of ​​the first epitaxial structure and the second epitaxial structure is not too large or too small, thereby obtaining a suitable current density, ensuring that the internal quantum efficiency is maximized, and thus improving the brightness of the light-emitting diode.

[0032] In both epitaxial structures, the first semiconductor layer is connected via electrodes within recesses. In each epitaxial structure, two electrodes are arranged around the two recesses to connect to the second semiconductor layer. Then, electrodes on the reflective layer connect the electrodes within the recesses of the first epitaxial structure to the two electrodes on the second semiconductor layer of the second epitaxial structure, achieving series connection between the first and second epitaxial structures. Furthermore, two additional electrodes on the reflective layer serve as lead-out electrodes; one lead-out electrode is connected to the two electrodes on the second semiconductor layer of the first epitaxial structure, and the other lead-out electrode is connected to the electrode within the recess of the second epitaxial structure. This electrode distribution and connection method optimizes the electrode distribution and improves the current diffusion path, allowing it to diffuse throughout the entire epitaxial layer, further enhancing the brightness of the LED. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of this disclosure, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1This is a flowchart of a method for fabricating a light-emitting diode provided in an embodiment of this disclosure;

[0035] Figure 2 This is a flowchart of a method for fabricating a light-emitting diode provided in an embodiment of this disclosure;

[0036] Figure 3 This is a schematic diagram of the structure of the light-emitting diode provided in the embodiments of this disclosure during the fabrication process;

[0037] Figure 4 This is a schematic diagram of the structure of the light-emitting diode provided in the embodiments of this disclosure during the fabrication process;

[0038] Figure 5 This is a schematic diagram of the structure of the light-emitting diode provided in the embodiments of this disclosure during the fabrication process;

[0039] Figure 6 This is a schematic diagram of the structure of the light-emitting diode provided in the embodiments of this disclosure during the fabrication process;

[0040] Figure 7 This is a schematic diagram of the structure of the light-emitting diode provided in the embodiments of this disclosure during the fabrication process;

[0041] Figure 8 This is a schematic diagram of the structure of the light-emitting diode provided in the embodiments of this disclosure during the fabrication process;

[0042] Figure 9 This is a schematic diagram of the structure of the light-emitting diode provided in the embodiments of this disclosure during the fabrication process;

[0043] Figure 10 This is a schematic diagram of the structure of the light-emitting diode provided in the embodiments of this disclosure during the fabrication process;

[0044] Figure 11 This is a schematic diagram of the structure of a light-emitting diode provided in an embodiment of this disclosure;

[0045] Figure 12 This is a schematic diagram of the cross-section of a light-emitting diode (LED) along line A-A' provided in an embodiment of this disclosure.

[0046] Figure 13 This is a schematic diagram of the cross-section of a light-emitting diode B-B' provided in an embodiment of this disclosure.

[0047] The attached figures are labeled as follows:

[0048] 10: Epitaxial structure; 11: First epitaxial structure; 12: Second epitaxial structure; 20: First electrode structure; 30: Second electrode structure; 40: Electrode pad structure;

[0049] 100: Substrate; 101: First semiconductor layer; 102: Active layer; 103: Second semiconductor layer; 104: Current blocking layer; 105: Transparent conductive layer; 106: Reflective layer; 107: Passivation layer;

[0050] 1041: First current blocking layer; 1042: Second current blocking layer;

[0051] 1051: First transparent conductive layer; 1052: Second transparent conductive layer;

[0052] 201: First electrode; 202: Second electrode; 203: Third electrode; 204: Fourth electrode; 205: Fifth electrode; 206: Sixth electrode;

[0053] 301: Seventh electrode; 302: Eighth electrode; 303: Ninth electrode; 321: First part; 322: Second part;

[0054] 401: First electrode pad; 402: Second electrode pad;

[0055] 1000: Isolation groove; 1001: First through hole; 1002: Second through hole; 1003: Third through hole;

[0056] 2001: First groove; 2002: Second groove. Detailed Implementation

[0057] To make the objectives, technical solutions, and advantages of this disclosure clearer, the embodiments of this disclosure will be described in further detail below with reference to the accompanying drawings.

[0058] Figure 1 This is a flowchart illustrating a method for fabricating a light-emitting diode (LED) according to an embodiment of this disclosure. See also... Figure 1 The method includes the following steps:

[0059] S11. An epitaxial structure is fabricated on a substrate. The epitaxial structure has an isolation trench. The epitaxial structure is divided into a first epitaxial structure and a second epitaxial structure by the isolation trench. The ratio of the sum of the surface areas of the first epitaxial structure and the second epitaxial structure to the surface area of ​​the substrate is 65-70%. Both the first epitaxial structure and the second epitaxial structure include a first semiconductor layer, an active layer, and a second semiconductor layer stacked sequentially. The first epitaxial structure has a first groove with its bottom located on the first semiconductor layer, and the second epitaxial structure has a second groove with its bottom located on the first semiconductor layer.

[0060] S12. Fabricate a first electrode structure, the first electrode structure including a first electrode, a second electrode, a third electrode, a fourth electrode, a fifth electrode and a sixth electrode, the second electrode being located in the first groove, the fourth electrode being located in the second groove; the first electrode and the third electrode being located on the second semiconductor layer on both sides of the first groove, the third electrode and the fifth electrode being located on the second semiconductor layer on both sides of the second groove.

[0061] S13. Fabricate a reflective layer, which covers the epitaxial structure and the first electrode structure.

[0062] S14. Fabricate a second electrode structure, the second electrode structure including a seventh electrode, an eighth electrode and a ninth electrode located on the reflective layer, the seventh electrode passing through the reflective layer and electrically connected to the first electrode and the third electrode respectively, one side of the eighth electrode passing through the reflective layer and electrically connected to the second electrode, the other side of the eighth electrode passing through the reflective layer and electrically connected to the fourth electrode and the sixth electrode respectively, and the ninth electrode passing through the reflective layer and electrically connected to the fifth electrode.

[0063] In this embodiment, the epitaxial structure is divided into a first epitaxial structure and a second epitaxial structure by an isolation trench. The ratio of the sum of the surface areas of the first and second epitaxial structures to the surface area of ​​the substrate is 65-70%. Under the premise of the same operating current, changing the area of ​​the light-emitting region will affect the luminous efficiency of the light-emitting diode chip. For LEDs with low operating current, appropriately reducing their light-emitting area can increase the current density of the LED chip, improve the internal quantum efficiency, and achieve the effect of improving brightness. Therefore, the ratio of the sum of the surface areas of the first and second epitaxial structures to the surface area of ​​the substrate is 65-70%, which is relatively high compared to related... In this technology, the surface area ratio of the epitaxial structure to the substrate is 86.7%, which improves the brightness of the light-emitting diode. Both the first epitaxial structure and the second epitaxial structure include a first semiconductor layer, an active layer, and a second semiconductor layer stacked sequentially. The first epitaxial structure has a first groove with its bottom located on the first semiconductor layer, and the second epitaxial structure has a second groove with its bottom located on the first semiconductor layer. In this embodiment, the first groove, the second groove, and the isolation trench ensure that the area of ​​the first epitaxial structure and the second epitaxial structure is not too large or too small, thereby obtaining a suitable current density, ensuring that the internal quantum efficiency is maximized, and thus improving the brightness of the light-emitting diode.

[0064] In both epitaxial structures, the first semiconductor layer is connected via electrodes within recesses. In each epitaxial structure, two electrodes are arranged around the two recesses to connect to the second semiconductor layer. Then, electrodes on the reflective layer connect the electrodes within the recesses of the first epitaxial structure to the two electrodes on the second semiconductor layer of the second epitaxial structure, achieving series connection between the first and second epitaxial structures. Furthermore, two additional electrodes on the reflective layer serve as lead-out electrodes; one lead-out electrode is connected to the two electrodes on the second semiconductor layer of the first epitaxial structure, and the other lead-out electrode is connected to the electrode within the recess of the second epitaxial structure. This electrode distribution and connection method optimizes the electrode distribution and improves the current diffusion path, allowing it to diffuse throughout the entire epitaxial layer, further enhancing the brightness of the LED.

[0065] Figure 2 This is a flowchart illustrating a method for fabricating a light-emitting diode (LED) according to an embodiment of this disclosure. See also... Figure 2 The method includes the following steps:

[0066] S21. A first semiconductor layer, an active layer, and a second semiconductor layer are sequentially formed on a substrate, and the first semiconductor layer, the active layer, and the second semiconductor layer constitute an epitaxial structure.

[0067] The substrate can be a sapphire substrate.

[0068] In one example, step S21 includes:

[0069] The first step is to fabricate the first semiconductor layer.

[0070] In this embodiment of the disclosure, the first semiconductor layer may be an N-type semiconductor layer. For example, the first semiconductor layer may be an N-type GaN layer.

[0071] In other embodiments, the first semiconductor layer may be a P-type semiconductor layer.

[0072] The second step is to create the active layer.

[0073] In this embodiment, the active layer is a multi-quantum-well layer. For example, an InGaN / GaN multi-quantum-well layer.

[0074] The third step is to fabricate the second semiconductor layer.

[0075] In this embodiment of the disclosure, the second semiconductor layer may be a P-type semiconductor layer. For example, the second semiconductor layer may be a P-type GaN layer.

[0076] In other embodiments, the second semiconductor layer may be an N-type semiconductor layer.

[0077] In this embodiment of the disclosure, a first semiconductor layer, an active layer, and a second semiconductor layer are sequentially stacked on a substrate.

[0078] In the embodiments disclosed herein, the above-mentioned semiconductor layer can be grown using a Veeco K465i, C4, or RB MOCVD (Metal Organic Chemical Vapor Deposition) apparatus or an AIXTRON MOCVD apparatus. High-purity H2 (hydrogen), high-purity N2 (nitrogen), or a mixture of high-purity H2 and high-purity N2 is used as the carrier gas; high-purity NH3 is used as the N source; trimethylgallium (TMGa) and triethylgallium (TEGa) are used as gallium sources; trimethylindium (TMIn) is used as the indium source; silane (SiH4) is used as the N-type dopant; trimethylaluminum (TMAl) is used as the aluminum source; and magnesium pyrocene (CP2Mg) is used as the P-type dopant.

[0079] It is worth noting that other equipment can also be used to fabricate the aforementioned semiconductor layer, and this disclosure does not limit this.

[0080] In this embodiment, the surface area of ​​the second semiconductor layer can be 47,000 to 48,000 μm. 2 .

[0081] In this implementation, the surface area of ​​the second semiconductor layer is 47,000–48,000 μm. 2 This allows the second semiconductor layer to reach a suitable area, increasing the current density of the LED and improving its brightness.

[0082] For example, the surface area of ​​the second semiconductor layer is 47500 μm. 2 .

[0083] S22. The extensional structure is graphically processed to form a first extensional structure and a second extensional structure. The first extensional structure is a first step structure with a first step bottom surface and a first step top surface. The second extensional structure is a second step structure with a second step bottom surface and a second step top surface. There is an isolation groove between the first extensional structure and the second extensional structure.

[0084] In this embodiment of the disclosure, two photolithography developments are used, and dry etching technology is used to etch the epitaxial structure.

[0085] In this embodiment, the sum of the surface areas of the first epitaxial structure and the second epitaxial structure is 47,000–48,000 μm. 2 .

[0086] In this implementation, under the premise of the same operating current, changing the area of ​​the light-emitting region will affect the luminous efficiency of the LED chip, and the sum of the surface areas of the first epitaxial structure and the second epitaxial structure is 47000~48000μm. 2 The luminescent area is precisely controlled at the maximum brightness, compared to the surface area of ​​epitaxial structures in related technologies, which is 60,000–61,000 μm. 2 This improves the brightness of the light-emitting diode.

[0087] As the injected current density increases, the internal quantum efficiency initially rises and then falls, a phenomenon known as quantum efficiency decay. However, within a certain current density range, the current density is directly proportional to the internal quantum efficiency. Therefore, for LEDs with low operating current, appropriately reducing their luminous area can increase the LED chip current density, thereby improving the internal quantum efficiency and ultimately enhancing brightness.

[0088] For example, the sum of the surface areas of the first epitaxial structure and the second epitaxial structure is 47500 μm. 2 .

[0089] In the embodiments of this disclosure, the distance between the edges of the projections of the first epitaxial structure and the second epitaxial structure onto the substrate surface and the substrate edge can be 6 to 8 μm.

[0090] For example, the distance between the edges of the projections of the first epitaxial structure and the second epitaxial structure onto the substrate surface and the substrate edge is 6-8 μm, which allows the sum of the surface areas of the first epitaxial structure and the second epitaxial structure to be precisely controlled within the luminous area of ​​maximum brightness, thereby achieving the effect of brightness enhancement.

[0091] For example, the distance between the edges of the projections of the first epitaxial structure and the second epitaxial structure onto the substrate surface and the substrate edge is 7 μm.

[0092] Figure 3 This is a schematic diagram of the structure of a light-emitting diode (LED) provided in an embodiment of this disclosure during its fabrication process. See also... Figure 3 The epitaxial structure 10 has an isolation trench 1000, which divides the epitaxial structure 10 into a first epitaxial structure 11 and a second epitaxial structure 12. The first epitaxial structure 11 and the second epitaxial structure 12 each include a first semiconductor layer 101, an active layer 102 and a second semiconductor layer 103 stacked sequentially. The first epitaxial structure 11 has a first groove 2001 with its bottom located on the first semiconductor layer 101, and the second epitaxial structure 12 has a second groove 2002 with its bottom located on the first semiconductor layer 101.

[0093] S23. Fabricate a current blocking layer, which includes a first current blocking layer and a second current blocking layer, and the first current blocking layer and the second current blocking layer are located on the first epitaxial structure and the second epitaxial structure, respectively.

[0094] For example, step S23 may include:

[0095] The first step is to deposit a current-blocking film.

[0096] In this embodiment of the disclosure, the current blocking film can be a current blocking film fabricated by plasma enhanced chemical vapor deposition (PECVD).

[0097] In this embodiment of the disclosure, the current blocking film can be an AlGaN or SiO2 layer.

[0098] For example, the current blocking film is a SiO2 current blocking layer.

[0099] The second step is to coat a layer of photoresist onto the current blocking film.

[0100] The third step is to expose the photoresist.

[0101] The fourth step is to etch the current blocking film to form the first current blocking layer and the second current blocking layer.

[0102] In this embodiment of the disclosure, the current blocking film layer is subjected to buffered oxide etching (BOE).

[0103] Figure 4 This is a schematic diagram of the structure of a light-emitting diode (LED) provided in an embodiment of this disclosure during its fabrication process. See also... Figure 4 ,exist Figure 3 A current blocking layer is fabricated on the basis of the first epitaxial structure 11 and the second epitaxial structure 12. The current blocking layer 104 includes a first current blocking layer 1041 and a second current blocking layer 1042, which are respectively located on the first epitaxial structure 11 and the second epitaxial structure 12.

[0104] The current blocking layer 104 includes a first current blocking layer 1041 and a second current blocking layer 1042, which are located on the first epitaxial structure 11 and the second epitaxial structure 12, respectively.

[0105] S24. Fabricate a transparent conductive layer, which includes a first transparent conductive layer and a second transparent conductive layer. The first transparent conductive layer and the second transparent conductive layer respectively cover the first current blocking layer and the second current blocking layer, and are respectively connected to the first epitaxial structure and the second epitaxial structure.

[0106] For example, step S24 may include:

[0107] The first step is to deposit a transparent conductive film layer on the first current blocking layer and the second current blocking layer, respectively.

[0108] In this embodiment, the transparent conductive film layer can be an ITO layer. ITO has excellent transparency and conductivity, and can conduct current to form an electrical connection while light passes through.

[0109] The second step is to coat a layer of photoresist onto the transparent conductive film.

[0110] The third step is to expose the photoresist.

[0111] The fourth step involves etching the transparent conductive film to form the first and second transparent conductive layers.

[0112] In this embodiment of the disclosure, the transparent conductive film layer is etched using BOE etching.

[0113] Figure 5 This is a schematic diagram of the structure of a light-emitting diode (LED) provided in an embodiment of this disclosure during its fabrication process. See also... Figure 5 ,exist Figure 4 A transparent conductive layer is fabricated on the basis of the first transparent conductive layer 105, which includes a first transparent conductive layer 1051 and a second transparent conductive layer 1052. The first transparent conductive layer 1051 and the second transparent conductive layer 1052 respectively cover the first current blocking layer 1041 and the second current blocking layer 1042, and are respectively connected to the first epitaxial structure 11 and the second epitaxial structure 12.

[0114] S25. Fabricate a first electrode structure, which includes a first electrode, a second electrode, a third electrode, a fourth electrode, a fifth electrode, and a sixth electrode.

[0115] In this embodiment of the disclosure, the first electrode, the second electrode, the third electrode, the fourth electrode, the fifth electrode, and the sixth electrode are formed by metal evaporation.

[0116] In this embodiment of the disclosure, the first electrode, the third electrode, the fourth electrode, and the sixth electrode can be P electrodes, and the second electrode and the sixth electrode can be N electrodes.

[0117] In other embodiments, the first electrode, the third electrode, the fourth electrode, and the sixth electrode can be N electrodes, and the second electrode and the sixth electrode can be P electrodes.

[0118] In the embodiments of this disclosure, the first electrode, the second electrode, the third electrode, the fourth electrode, the fifth electrode, and the sixth electrode can be Cr, Al, Ti, Ni, Pt, or Au electrodes.

[0119] Alternatively, the first electrode, second electrode, third electrode, fourth electrode, fifth electrode, and sixth electrode can be stacked electrodes of at least two of Cr, Al, Ti, Ni, Pt, and Au.

[0120] For example, the first electrode, the second electrode, the third electrode, the fourth electrode, the fifth electrode, and the sixth electrode are Cr electrodes.

[0121] In this embodiment of the disclosure, the distance between the second electrode and the first electrode is equal to the distance between the second electrode and the third electrode, and the distance between the fifth electrode and the fourth electrode and the distance between the fifth electrode and the sixth electrode are equal.

[0122] In this implementation, the distances between the second electrode and the first electrode, and between the second electrode and the third electrode, as well as the distances between the fifth electrode and the fourth electrode and between the fifth electrode and the sixth electrode, are equal. This makes the distribution of these electrodes more uniform, allowing the diffused current to cover a larger epitaxial area, which in turn improves current spread and quantum efficiency. Furthermore, the equidistant arrangement makes the current distribution more uniform, thus increasing the brightness of the light-emitting diode.

[0123] Figure 6 This is a schematic diagram of the structure of a light-emitting diode (LED) provided in an embodiment of this disclosure during its fabrication process. See also... Figure 6 ,exist Figure 5 Based on this, a first electrode structure 20 is fabricated. The first electrode structure 20 includes a first electrode 201, a second electrode 202, a third electrode 203, a fourth electrode 204, a fifth electrode 205, and a sixth electrode 206. The second electrode 202 is located in the first groove 2001, and the fifth electrode 205 is located in the second groove 2002. The first electrode 201 and the third electrode 203 are located on the second semiconductor layer 103 on both sides of the first groove 2001, and the fourth electrode 204 and the sixth electrode 206 are located on the second semiconductor layer 103 on both sides of the second groove 2002.

[0124] S26. Create a reflective layer.

[0125] The first step is to make a reflective film.

[0126] In this embodiment of the disclosure, a reflective film is deposited using a PVD coating machine.

[0127] In this embodiment of the disclosure, the reflective film may be a DBR reflective film.

[0128] In this embodiment of the disclosure, the DBR reflective film can be a stack of alternating SiO2 and Ti3O5 layers.

[0129] In this embodiment of the disclosure, the alternation period of the SiO2 layer and the Ti3O5 layer can be 4 to 13 cycles.

[0130] For example, the alternation period of SiO2 layer and Ti3O5 layer can be 6 cycles.

[0131] The second step is to create the first through-hole in the reflective film to form a reflective layer.

[0132] In this embodiment of the disclosure, a first through-hole is fabricated on the reflective film using a dry etching technique.

[0133] In this embodiment of the present disclosure, the reflective layer has a first through hole corresponding to the first electrode structure, and the first electrode structure is connected to the epitaxial structure through the first through hole.

[0134] Figure 7 This is a schematic diagram of the structure of a light-emitting diode (LED) provided in an embodiment of this disclosure during its fabrication process. See also... Figure 7 ,exist Figure 6 A reflective layer is fabricated on the basis of the epitaxial structure 10 and the first electrode structure 20.

[0135] S27. Fabricate a second electrode structure, which includes a seventh electrode, an eighth electrode, and a ninth electrode.

[0136] In this embodiment of the disclosure, a second electrode structure is deposited using a metal evaporator.

[0137] In the embodiments of this disclosure, the seventh, eighth, and ninth electrodes can be Cr, Al, Ti, Ni, Pt, or Au electrodes.

[0138] Alternatively, the seventh, eighth, and ninth electrodes can be stacked electrodes made of at least two of Cr, Al, Ti, Ni, Pt, and Au.

[0139] For example, the seventh, eighth, and ninth electrodes are Cr electrodes.

[0140] In this embodiment, the seventh electrode is a U-shaped structure, with the two arms of the U-shaped structure connected to the first electrode and the third electrode, respectively.

[0141] In this implementation, the seventh electrode has a U-shaped structure that can avoid the second electrode in the first groove and connect with the first electrode and the third electrode, thus optimizing the electrode arrangement and making the light-emitting diode structure more compact.

[0142] In this embodiment of the disclosure, the eighth electrode includes a first part and a second part. The first part is strip-shaped, with one end of the first part connected to the second electrode and the other end of the first part connected to the second part. The second part is ring-shaped, with the fourth electrode and the sixth electrode connected to both sides of the ring. The ninth electrode is located within the ring.

[0143] In this implementation, the eighth electrode includes a first part and a second part. The first part is strip-shaped and can be connected to the second electrode independently. The other end of the first part is connected to the second part, which can connect the first epitaxial structure and the second epitaxial structure in series. The second part is ring-shaped, with the fourth electrode and the sixth electrode connected to both sides of the ring. The ring shape can increase the current expansion area, avoid current accumulation, and increase the brightness of the light-emitting diode.

[0144] In this embodiment of the disclosure, the ninth electrode is a rounded rectangle, and the rounded rectangle is similar in shape to the inner ring of the ring in the eighth electrode.

[0145] In this implementation, the ninth electrode is a rounded rectangle with a similar shape to the inner ring of the rounded rectangle in the eighth electrode, which allows for more uniform current diffusion. This further optimizes the current distribution and improves the brightness of the LED.

[0146] Figure 8 This is a schematic diagram of the structure of a light-emitting diode (LED) provided in an embodiment of this disclosure during its fabrication process. See also... Figure 8 ,exist Figure 7 Based on this, a second electrode structure is fabricated. The second electrode structure 30 includes a seventh electrode 301, an eighth electrode 302, and a ninth electrode 303 located on the reflective layer 106. The seventh electrode 301 passes through the reflective layer 106 and is electrically connected to the first electrode 201 and the third electrode 203 respectively. One side of the eighth electrode 302 passes through the reflective layer 106 and is electrically connected to the second electrode 202. The other side of the eighth electrode 302 passes through the reflective layer 106 and is electrically connected to the fourth electrode 204 and the sixth electrode 206 respectively. The ninth electrode 303 passes through the reflective layer 106 and is electrically connected to the fifth electrode 205.

[0147] S28. Fabricate a passivation layer, which covers the reflective layer and the second electrode structure.

[0148] In this embodiment of the disclosure, step S28 may include:

[0149] The first step is to create a passivation layer.

[0150] In this embodiment of the disclosure, the passivation layer can be a passivation layer fabricated by PECVD.

[0151] In this embodiment of the disclosure, the passivation layer may be SiO2, Si3N4, or SiN. x Or a passivation layer made of SiON, where x is greater than 0.

[0152] For example, the passivation layer is a SiO2 layer.

[0153] In this embodiment of the disclosure, the thickness of the passivation layer can be 10,000 to 30,000 angstroms.

[0154] For example, the thickness of the passivation layer is 20,000 angstroms.

[0155] The second step is to create a second and a third through-hole by opening holes in the passivation layer.

[0156] In this embodiment of the present disclosure, the passivation layer includes six second vias and two third vias. The projections of the six second vias in groups of three surround the first electrode and the third electrode on the bottom surface of the first epitaxial structure, respectively. The projections of the two third vias on the bottom surface of the second epitaxial structure include those located on both sides of the fifth electrode.

[0157] In this implementation, the six-hole second through-hole allows the second electrode structure and the first electrode to be connected, and the above arrangement can prevent current concentration.

[0158] In other embodiments, the passivation layer may also include other numbers of second and third vias. For example, eight second vias and four third vias.

[0159] In this embodiment of the disclosure, the first through hole and the second through hole are circular, and the third through hole is a rounded rectangle.

[0160] Figure 9 This is a schematic diagram of the structure of a light-emitting diode (LED) provided in an embodiment of this disclosure during its fabrication process. See also... Figure 9 ,exist Figure 8 A passivation layer is fabricated on the basis of the passivation layer 107, which covers the reflective layer 106 and the second electrode structure 30.

[0161] S29. Fabricate an electrode pad structure, which includes a first electrode pad and a second electrode pad. The first electrode pad passes through the passivation layer and is connected to the seventh electrode, and the second electrode pad passes through the passivation layer and is connected to the ninth electrode.

[0162] In this embodiment of the disclosure, metal evaporation deposition is used to deposit the first electrode pad and the second electrode pad.

[0163] In this embodiment of the disclosure, the first electrode pad and the second electrode pad can be Cr, Al, Ti, Ni, Pt or Au electrodes.

[0164] Alternatively, the first electrode pad and the second electrode pad can be stacked electrodes of at least two of Cr, Al, Ti, Ni, Pt and Au.

[0165] For example, the first electrode pad and the second electrode pad are Cr electrodes.

[0166] Figure 10 This is a schematic diagram of the structure of a light-emitting diode (LED) provided in an embodiment of this disclosure during its fabrication process. See also... Figure 10 ,exist Figure 9Based on this, an electrode pad structure is fabricated. The electrode pad structure 40 includes a first electrode pad 401 and a second electrode pad 402. The first electrode pad 401 passes through the passivation layer 107 and is connected to the seventh electrode 301. The second electrode pad 402 passes through the passivation layer 107 and is connected to the ninth electrode 303.

[0167] S30, thinned substrate.

[0168] By thinning and grinding, the chip thickness can be reduced to match the needs of downstream markets.

[0169] S31, Cutting the light-emitting diode.

[0170] In this embodiment of the disclosure, step S31 may include:

[0171] The first step is to dicing the light-emitting diodes.

[0172] In this embodiment, the front side of the entire wafer is attached to an adhesive polymer film, and the back side is diced using a hidden dicing machine. Based on the wafer structure, the wafer is cut in the order of first the obliquely diced side and then the non-obliquely diced side.

[0173] The second step is to cleave the fragments.

[0174] After the hidden dicing machine completes its processing, the wafer is diced.

[0175] The third step is to perform automated optical inspection (AOI).

[0176] The fourth step is to pour and expand the film.

[0177] Figure 11 This is a schematic diagram of the structure of a light-emitting diode provided in an embodiment of this disclosure. (Reference) Figure 11 The light-emitting diode includes: a substrate 100, an epitaxial structure 10, a first electrode structure 20, a reflective layer 106, and a second electrode structure 30.

[0178] Figure 12 This is a schematic diagram of the cross-section of a light-emitting diode (LED) along line A-A' provided in an embodiment of this disclosure. Figure 13 This is a schematic diagram of the B-B' cross-section of a light-emitting diode provided in an embodiment of this disclosure. See also... Figures 3 to 13The epitaxial structure 10 is located on the substrate 100. The epitaxial structure 10 has an isolation trench 1000. The epitaxial structure 10 is divided into a first epitaxial structure 11 and a second epitaxial structure 12 by the isolation trench 1000. The ratio of the sum of the surface areas of the first epitaxial structure 11 and the second epitaxial structure 12 to the surface area of ​​the substrate 100 is 65-70%. The first epitaxial structure 11 and the second epitaxial structure 12 each include a first semiconductor layer 101, an active layer 102 and a second semiconductor layer 103 stacked sequentially. The first epitaxial structure 11 has a first groove 2001 with its bottom located on the first semiconductor layer 101, and the second epitaxial structure 12 has a second groove 2002 with its bottom located on the first semiconductor layer 101.

[0179] The first electrode structure 20 includes a first electrode 201, a second electrode 202, a third electrode 203, a fourth electrode 204, a fifth electrode 205, and a sixth electrode 206. The second electrode 202 is located in the first groove 2001, and the fifth electrode 205 is located in the second groove 2002. The first electrode 201 and the third electrode 203 are located on the second semiconductor layer 103 on both sides of the first groove 2001, and the fourth electrode 204 and the sixth electrode 206 are located on the second semiconductor layer 103 on both sides of the second groove 2002.

[0180] It should be noted that the second electrode 202 is located in the first groove 2001 and is insulated from the active layer 102 and the second semiconductor layer 103, and the fifth electrode 205 is located in the second groove 2002 and is insulated from the active layer 102 and the second semiconductor layer 103.

[0181] The reflective layer 106 covers the epitaxial structure 10 and the first electrode structure 20.

[0182] The second electrode structure 30 includes a seventh electrode 301, an eighth electrode 302, and a ninth electrode 303 located on the reflective layer 106. The seventh electrode 301 passes through the reflective layer 106 and is electrically connected to the first electrode 201 and the third electrode 203, respectively. One side of the eighth electrode 302 passes through the reflective layer 106 and is electrically connected to the second electrode 202. The other side of the eighth electrode 302 passes through the reflective layer 106 and is electrically connected to the fourth electrode 204 and the sixth electrode 206, respectively. The ninth electrode 303 passes through the reflective layer 106 and is electrically connected to the fifth electrode 205.

[0183] In this embodiment, the epitaxial structure is divided into a first epitaxial structure and a second epitaxial structure by an isolation trench. The ratio of the sum of the surface areas of the first and second epitaxial structures to the surface area of ​​the substrate is 65-70%. Under the premise of the same operating current, changing the area of ​​the light-emitting region will affect the luminous efficiency of the light-emitting diode chip. For LEDs with low operating current, appropriately reducing their light-emitting area can increase the current density of the LED chip, improve the internal quantum efficiency, and achieve the effect of improving brightness. Therefore, the ratio of the sum of the surface areas of the first and second epitaxial structures to the surface area of ​​the substrate is 65-70%, which is relatively high compared to related... In this technology, the surface area ratio of the epitaxial structure to the substrate is 86.7%, which improves the brightness of the light-emitting diode. Both the first epitaxial structure and the second epitaxial structure include a first semiconductor layer, an active layer, and a second semiconductor layer stacked sequentially. The first epitaxial structure has a first groove with its bottom located on the first semiconductor layer, and the second epitaxial structure has a second groove with its bottom located on the first semiconductor layer. In this embodiment, the first groove, the second groove, and the isolation trench ensure that the area of ​​the first epitaxial structure and the second epitaxial structure is not too large or too small, thereby obtaining a suitable current density, ensuring that the internal quantum efficiency is maximized, and thus improving the brightness of the light-emitting diode.

[0184] In both epitaxial structures, the first semiconductor layer is connected via electrodes within recesses. In each epitaxial structure, two electrodes are arranged around the two recesses to connect to the second semiconductor layer. Then, electrodes on the reflective layer connect the electrodes within the recesses of the first epitaxial structure to the two electrodes on the second semiconductor layer of the second epitaxial structure, achieving series connection between the first and second epitaxial structures. Furthermore, two additional electrodes on the reflective layer serve as lead-out electrodes; one lead-out electrode is connected to the two electrodes on the second semiconductor layer of the first epitaxial structure, and the other lead-out electrode is connected to the electrode within the recess of the second epitaxial structure. This electrode distribution and connection method optimizes the electrode distribution and improves the current diffusion path, allowing it to diffuse throughout the entire epitaxial layer, further enhancing the brightness of the LED.

[0185] In this embodiment, the reflective layer 106 has a plurality of through holes, which are respectively connected to the first electrode 201, the second electrode 202, the third electrode 203, the fourth electrode 204, the fifth electrode 205 and the sixth electrode 206.

[0186] Furthermore, since the reflective layer 106 is an insulating layer, it can fill the aforementioned first groove 2001 and second groove 2002, thereby insulating the electrodes in the groove from the sidewalls of the groove.

[0187] In this embodiment, the sum of the surface areas of the first epitaxial structure 11 and the second epitaxial structure 12 is 47,000 to 48,000 μm. 2 .

[0188] In this implementation, under the premise of the same operating current, changing the area of ​​the light-emitting region will affect the luminous efficiency of the LED chip, and the sum of the surface areas of the first epitaxial structure and the second epitaxial structure is 47000~48000μm. 2 The luminescent area is precisely controlled at the maximum brightness, compared to the surface area of ​​epitaxial structures in related technologies, which is 60,000–61,000 μm. 2 This improves the brightness of the light-emitting diode.

[0189] As the injected current density increases, the internal quantum efficiency initially rises and then falls, a phenomenon known as quantum efficiency decay. However, within a certain current density range, the current density is directly proportional to the internal quantum efficiency. Therefore, for LEDs with low operating current, appropriately reducing their luminous area can increase the LED chip current density, thereby improving the internal quantum efficiency and ultimately enhancing brightness.

[0190] For example, the sum of the surface areas of the first epitaxial structure 11 and the second epitaxial structure 12 is 47500 μm. 2 .

[0191] In this embodiment of the present disclosure, the distance between the edges of the projection of the first epitaxial structure 11 and the second epitaxial structure 12 onto the surface of the substrate 100 and the edge of the substrate 100 can be 6 to 8 μm.

[0192] For example, the distance between the edges of the projections of the first epitaxial structure and the second epitaxial structure onto the substrate surface and the substrate edge is 6-8 μm, which allows the sum of the surface areas of the first epitaxial structure and the second epitaxial structure to be precisely controlled within the luminous area of ​​maximum brightness, thereby achieving the effect of brightness enhancement.

[0193] For example, the distance between the edges of the projection of the first epitaxial structure 11 and the second epitaxial structure 12 onto the surface of the substrate 100 and the edge of the substrate 100 is 7 μm.

[0194] In this embodiment, the seventh electrode 301 has a U-shaped structure, and the two arms of the U-shaped structure are respectively connected to the first electrode 201 and the third electrode 203.

[0195] In this implementation, the seventh electrode has a U-shaped structure that can avoid the second electrode in the first groove and connect with the first and third electrodes, thus optimizing the electrode arrangement and making the light-emitting diode structure more compact.

[0196] In this embodiment of the disclosure, the eighth electrode 302 includes a first part 321 and a second part 322. The first part 321 is strip-shaped, with one end of the first part 321 connected to the second electrode 202 and the other end of the first part 321 connected to the second part 322. The second part 322 is annular, with the fourth electrode 204 and the sixth electrode 206 connected to the two sides of the annular ring respectively. The ninth electrode 303 is located within the annular ring.

[0197] In this implementation, the eighth electrode includes a first part and a second part. The first part is strip-shaped and can be connected to the second electrode independently. The other end of the first part is connected to the second part, which can connect the first epitaxial structure and the second epitaxial structure in series. The second part is ring-shaped, with the fourth electrode and the sixth electrode connected to both sides of the ring. The ring shape can increase the current expansion area, avoid current accumulation, and increase the brightness of the light-emitting diode.

[0198] In this embodiment of the disclosure, the ninth electrode 303 is a rounded rectangle, and the rounded rectangle is similar in shape to the inner ring of the ring in the eighth electrode 302.

[0199] In this implementation, the ninth electrode is a rounded rectangle, and the shape of the rounded rectangle is similar to the inner ring of the ring in the eighth electrode, which can make the current diffusion more uniform. This further optimizes the current distribution and improves the brightness of the light-emitting diode.

[0200] In this embodiment of the disclosure, the distance between the second electrode 202 and the first electrode 201 is equal to the distance between the second electrode 202 and the third electrode 203, and the distance between the fifth electrode 205 and the fourth electrode 204 and the distance between the fifth electrode 205 and the sixth electrode 206 are equal.

[0201] In this implementation, the distances between the second electrode and the first electrode, and between the second electrode and the third electrode, as well as the distances between the fifth electrode and the fourth electrode and between the fifth electrode and the sixth electrode, are equal. This makes the distribution of these electrodes more uniform, allowing the diffused current to cover a larger epitaxial area, which in turn improves current spread and quantum efficiency. Furthermore, the equidistant arrangement makes the current distribution more uniform, thus increasing the brightness of the light-emitting diode.

[0202] Optionally, the light-emitting diode also includes a current blocking layer 104 and a transparent conductive layer 105.

[0203] The current blocking layer 104 and the transparent conductive layer 105 are located between the epitaxial structure 10 and the reflective layer 106.

[0204] The current blocking layer 104 includes a first current blocking layer 1041 and a second current blocking layer 1042, which are located on the first epitaxial structure 11 and the second epitaxial structure 12, respectively.

[0205] The current blocking layer 104 includes a first current blocking layer 1041 and a second current blocking layer 1042, which are located on the first epitaxial structure 11 and the second epitaxial structure 12, respectively.

[0206] The transparent conductive layer 105 includes a first transparent conductive layer 1051 and a second transparent conductive layer 1052. The first transparent conductive layer 1051 and the second transparent conductive layer 1052 respectively cover the first current blocking layer 1041 and the second current blocking layer 1042, and are respectively connected to the first epitaxial structure 11 and the second epitaxial structure 12.

[0207] Optionally, the light-emitting diode also includes a passivation layer 107.

[0208] The passivation layer 107 covers the reflective layer 106 and the second electrode structure 30.

[0209] In this embodiment, the passivation layer 107 includes six second vias 1002 and two third vias 1003. The projections of the six second vias 1002 in groups of three surround the first electrode 201 and the third electrode 203 on the bottom surface of the first epitaxial structure. The projections of the two third vias 100 on the bottom surface of the second epitaxial structure 12 include those located on both sides of the fifth electrode 205.

[0210] In this implementation, the six-hole second through-hole allows the second electrode structure and the first electrode to be connected, and the above arrangement can prevent current concentration.

[0211] In other embodiments, the passivation layer 107 may also include other numbers of second vias 1002 and third vias 1003. For example, eight second vias 1002 and four third vias 1003.

[0212] In this embodiment, the first through hole 1001 and the second through hole 1002 are circular, and the third through hole 1003 is a rounded rectangle.

[0213] In this implementation, because the size of the light-emitting diode is small, the opening area is limited when etching the via. Considering that the area of ​​the via needs to be as large as possible (the larger the area, the higher the conduction efficiency), the above-mentioned shape has the highest current conduction efficiency.

[0214] Optionally, the light-emitting diode also includes an electrode pad structure 40.

[0215] The electrode pad structure 40 includes a first electrode pad 401 and a second electrode pad 402. The first electrode pad 401 passes through the passivation layer 107 and is connected to the seventh electrode 301, and the second electrode pad 402 passes through the passivation layer 107 and is connected to the ninth electrode 303.

[0216] In the embodiments of this disclosure, the current blocking layer and the transparent conductive layer on the epitaxial structure can expand the current, avoid current concentration, optimize the current distribution, and effectively improve the luminous efficiency of the light-emitting diode; the passivation layer can provide protection for the light-emitting diode, avoid the influence of the external environment, and improve the yield of the light-emitting diode; the electrode pad structure can provide an electrical channel for the light-emitting diode to be electrically connected to the outside world.

[0217] In this embodiment of the disclosure, the substrate 100 can be any one of a sapphire substrate, a Si substrate, or a SiC substrate, and the material of the substrate 100 is not limited in this embodiment of the disclosure.

[0218] For example, substrate 100 is a sapphire substrate.

[0219] In this embodiment of the disclosure, the first semiconductor layer 101 can be an N-type semiconductor layer, and the second semiconductor layer 103 can be a P-type semiconductor layer.

[0220] For example, the first semiconductor layer 101 can be an N-type GaN layer, and the second semiconductor layer 103 can be a P-type GaN layer.

[0221] In this embodiment of the disclosure, the active layer 102 can be a multi-quantum well layer, such as an InGaN / GaN multi-quantum well layer.

[0222] In other embodiments, the first semiconductor layer 101 may be a P-type semiconductor layer, and the second semiconductor layer 103 may be an N-type semiconductor layer.

[0223] In this embodiment of the disclosure, the current blocking layer 104 can be an AlGaN or SiO2 layer.

[0224] For example, the current blocking layer 104 is a SiO2 current blocking layer.

[0225] In this embodiment of the disclosure, the first transparent conductive layer 1051 and the second transparent conductive layer 1052 can be indium tin oxide (ITO) layers. ITO has good transparency and conductivity, and can conduct current to form an electrical connection while light passes through.

[0226] In one example, the first transparent conductive layer 1051 and the second transparent conductive layer 1052 are full-surface non-perforated film layers.

[0227] In other examples, the first transparent conductive layer 1051 and the second transparent conductive layer 1052 can also be films with a perforated pattern. Reducing the ohmic contact between the transparent conductive layer and the epitaxial layer increases the current density of the chip, thereby increasing the chip's quantum efficiency and achieving a brighter appearance.

[0228] In this embodiment of the disclosure, the reflective layer 106 may be a distributed Bragg reflector (DBR) layer.

[0229] In this embodiment of the disclosure, the DBR layer can be a stack of alternating SiO2 and Ti3O5 layers.

[0230] In this embodiment of the disclosure, the alternation period of the SiO2 layer and the Ti3O5 layer can be 4 to 13 cycles.

[0231] For example, the alternation period of SiO2 layer and Ti3O5 layer can be 6 cycles.

[0232] In this embodiment, the passivation layer 107 can be SiO2, Si3N4, or SiN. x Or a SiON layer, where x is greater than 0.

[0233] For example, the passivation layer 107 is a SiO2 layer.

[0234] In this embodiment of the disclosure, the thickness of the passivation layer 107 can be 10,000 to 30,000 angstroms.

[0235] For example, the passivation layer 107 has a thickness of 20,000 angstroms.

[0236] In this embodiment of the disclosure, the first electrode 201, the second electrode 202, the third electrode 203, the fourth electrode 204, the fifth electrode 205, the sixth electrode 206, the seventh electrode 301, the eighth electrode 302 and the ninth electrode 303 can be Cr, Al, Ti, Ni, Pt or Au electrodes.

[0237] Alternatively, the first electrode 201, the second electrode 202, the third electrode 203, the fourth electrode 204, the fifth electrode 205, the sixth electrode 206, the seventh electrode 301, the eighth electrode 302, and the ninth electrode 303 can be stacked electrodes of at least two of Cr, Al, Ti, Ni, Pt, and Au.

[0238] For example, the first electrode 201, the second electrode 202, the third electrode 203, the fourth electrode 204, the fifth electrode 205, the sixth electrode 206, the seventh electrode 301, the eighth electrode 302 and the ninth electrode 303 are Cr electrodes.

[0239] In this embodiment of the disclosure, the first electrode pad 401 and the second electrode pad 402 can be Cr, Al, Ti, Ni, Pt or Au electrode pads.

[0240] Alternatively, the first electrode pad 401 and the second electrode pad 402 can be stacked electrode pads of at least two of Cr, Al, Ti, Ni, Pt and Au.

[0241] For example, the first electrode pad 401 and the second electrode pad 402 are Cr electrodes.

[0242] In this embodiment, two light-emitting diode chips with different second semiconductor layer areas were subjected to full photoelectric performance testing and blue light packaging testing. The experimental results show that the brightness of the light-emitting diode provided in this embodiment is improved after the second semiconductor layer is reduced in size. The experimental data are shown in Table 1 below.

[0243] Table 1

[0244]

[0245]

[0246] In Table 1, WD represents the principal wavelength in nm; IV represents luminance in lm; ΔIV represents the percentage increase in luminance of the LED provided in this embodiment compared to LEDs provided in related technologies; Vf represents the forward operating voltage in V; ΔVf represents the increase in forward operating voltage of the LED provided in this embodiment compared to LEDs provided in related technologies. AVG represents the mean. As shown in Table 1, under various current conditions, through comparison among experimental chips in the same group, reducing the area of ​​the second semiconductor layer effectively improves the chip's brightness.

[0247] Among them, processes one to three are three different manufacturing processes, and each process can serve as a control group, including eight groups of control experiments. This disclosure does not limit the parameters of each process.

[0248] The above description is merely an optional embodiment of this disclosure and is not intended to limit this disclosure. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the protection scope of this disclosure.

Claims

1. A light-emitting diode, characterized in that, The light-emitting diode includes: a substrate (100), an epitaxial structure (10), a first electrode structure (20), a reflective layer (106), and a second electrode structure (30); The epitaxial structure (10) is located on the substrate (100). The epitaxial structure (10) has an isolation trench (1000). The epitaxial structure (10) is divided into a first epitaxial structure (11) and a second epitaxial structure (12) by the isolation trench (1000). The sum of the surface areas of the first epitaxial structure (11) and the second epitaxial structure (12) is 65-70% of the surface area of ​​the substrate (100). Both the first epitaxial structure (11) and the second epitaxial structure (12) include a first semiconductor layer (101), an active layer (102), and a second semiconductor layer (103) stacked sequentially. The first epitaxial structure (11) has a first groove (2001) with its bottom located on the first semiconductor layer (101), and the second epitaxial structure (12) has a second groove (2002) with its bottom located on the first semiconductor layer (101). The first electrode structure (20) includes a first electrode (201), a second electrode (202), a third electrode (203), a fourth electrode (204), a fifth electrode (205), and a sixth electrode (206). The second electrode (202) is located in the first groove (2001), and the fifth electrode (205) is located in the second groove (2002). The first electrode (201) and the third electrode (203) are located on the second semiconductor layer (103) on both sides of the first groove (2001), and the fourth electrode (204) and the sixth electrode (206) are located on the second semiconductor layer (103) on both sides of the second groove (2002). The reflective layer (106) covers the epitaxial structure (10) and the first electrode structure (20); The second electrode structure (30) includes a seventh electrode (301), an eighth electrode (302), and a ninth electrode (303) located on the reflective layer (106). The seventh electrode (301) passes through the reflective layer (106) and is electrically connected to the first electrode (201) and the third electrode (203) respectively. One side of the eighth electrode (302) passes through the reflective layer (106) and is electrically connected to the second electrode (202). The other side of the eighth electrode (302) passes through the reflective layer (106) and is electrically connected to the fourth electrode (204) and the sixth electrode (206) respectively. The ninth electrode (303) passes through the reflective layer (106) and is electrically connected to the fifth electrode (205).

2. The light-emitting diode according to claim 1, characterized in that, The sum of the surface areas of the first epitaxial structure (11) and the second epitaxial structure (12) is 47,000 to 48,000 μm. 2 .

3. The light-emitting diode according to claim 1, characterized in that, The distance between the edges of the projections of the first epitaxial structure (11) and the second epitaxial structure (12) onto the surface of the substrate (100) and the edge of the substrate (100) is 6 to 8 μm.

4. The light-emitting diode according to any one of claims 1 to 3, characterized in that, The seventh electrode (301) has a U-shaped structure, and the two arms of the U-shaped structure are respectively connected to the first electrode (201) and the third electrode (203).

5. The light-emitting diode according to any one of claims 1 to 3, characterized in that, The eighth electrode (302) includes a first part (321) and a second part (322). The first part (321) is strip-shaped, with one end of the first part (321) connected to the second electrode (202) and the other end of the first part (321) connected to the second part (322). The second part (322) is ring-shaped, with the fourth electrode (204) and the sixth electrode (206) connected to the two sides of the ring respectively. The ninth electrode (303) is located inside the ring.

6. The light-emitting diode according to claim 5, characterized in that, The ninth electrode (303) is a rounded rectangle, and the rounded rectangle is similar in shape to the inner ring of the ring in the eighth electrode (302).

7. The light-emitting diode according to any one of claims 1 to 3, characterized in that, The distance between the second electrode (202) and the first electrode (201) is equal to the distance between the second electrode (202) and the third electrode (203), and the distance between the fifth electrode (205) and the fourth electrode (204) is equal to the distance between the fifth electrode (205) and the sixth electrode (206).

8. The light-emitting diode according to any one of claims 1 to 3, characterized in that, The light-emitting diode also includes a current blocking layer (104), a transparent conductive layer (105), a passivation layer (107), and an electrode pad structure (40); The current blocking layer (104) and the transparent conductive layer (105) are located between the epitaxial structure (10) and the reflective layer (106) in sequence; The current blocking layer (104) includes a first current blocking layer (1041) and a second current blocking layer (1042), wherein the first current blocking layer (1041) and the second current blocking layer (1042) are respectively located on the first epitaxial structure (11) and the second epitaxial structure (12); The transparent conductive layer (105) includes a first transparent conductive layer (1051) and a second transparent conductive layer (1052). The first transparent conductive layer (1051) and the second transparent conductive layer (1052) respectively cover the first current blocking layer (1041) and the second current blocking layer (1042), and are respectively connected to the first epitaxial structure (11) and the second epitaxial structure (12). The passivation layer (107) covers the reflective layer (106) and the second electrode structure (30); The electrode pad structure (40) includes a first electrode pad (401) and a second electrode pad (402). The first electrode pad (401) passes through the passivation layer (107) and is connected to the seventh electrode (301). The second electrode pad (402) passes through the passivation layer (107) and is connected to the ninth electrode (303).

9. A method for fabricating a light-emitting diode, characterized in that, The method includes: An epitaxial structure is fabricated on a substrate. The epitaxial structure has an isolation trench and is divided into a first epitaxial structure and a second epitaxial structure by the isolation trench. The sum of the surface areas of the first epitaxial structure and the second epitaxial structure is 65-70% of the surface area of ​​the substrate. Both the first epitaxial structure and the second epitaxial structure include a first semiconductor layer, an active layer, and a second semiconductor layer stacked sequentially. The first epitaxial structure has a first groove with its bottom located in the first semiconductor layer, and the second epitaxial structure has a second groove with its bottom located in the first semiconductor layer. A first electrode structure is fabricated, comprising a first electrode, a second electrode, a third electrode, a fourth electrode, a fifth electrode, and a sixth electrode. The second electrode is located in the first groove, and the fourth electrode is located in the second groove. The first electrode and the third electrode are located on the second semiconductor layer on both sides of the first groove, and the third electrode and the fifth electrode are located on the second semiconductor layer on both sides of the second groove. A reflective layer is fabricated, which covers the epitaxial structure and the first electrode structure; A second electrode structure is fabricated, comprising a seventh electrode, an eighth electrode, and a ninth electrode located on the reflective layer. The seventh electrode passes through the reflective layer and is electrically connected to the first electrode and the third electrode, respectively. One side of the eighth electrode passes through the reflective layer and is electrically connected to the second electrode, and the other side of the eighth electrode passes through the reflective layer and is electrically connected to the fourth electrode and the sixth electrode, respectively. The ninth electrode passes through the reflective layer and is electrically connected to the fifth electrode.

10. The method according to claim 9, characterized in that, The sum of the surface areas of the first epitaxial structure and the second epitaxial structure is 47,000–48,000 μm. 2 .

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