Light emitting element

Abstract

The present application provides a light emitting element, comprising: a semiconductor stack comprising a first semiconductor layer, an active layer, and a second semiconductor layer stacked in this order; a second insulating layer formed on the semiconductor stack, the second insulating layer having a first opening portion in a second portion of the outer peripheral portion, the first opening portion comprising a first side wall away from an edge of the light emitting element and a second side wall close to the edge of the light emitting element; and a first connection electrode formed on the semiconductor stack, the first connection electrode comprising a portion extending to the outer peripheral portion and contacting the first semiconductor layer through the first opening portion, the first connection electrode contacting the first side wall and the second side wall.

Description

Technical Field

[0001] This invention relates to the field of light-emitting element manufacturing technology, and in particular to a light-emitting element. Background Technology

[0002] A light-emitting diode (LED) is a solid-state semiconductor light-emitting element that contains various light-emitting materials and components. Due to its advantages such as low cost, low power consumption, high luminous efficiency, small size, energy saving, environmental friendliness, and excellent optoelectronic properties, it is widely used in various scenarios including lighting, visible light communication, and light-emitting displays.

[0003] Light-emitting elements used in automotive, backlighting, plant lighting, and high-power lighting typically use Ag, a metal with the highest reflectivity, as the primary mirror material, formed on a P-type semiconductor layer to improve the light extraction efficiency. To enhance the current spreading capability of these elements, a portion of the N-type semiconductor layer is usually etched at the edge of the element to expose the semiconductor stack, allowing the electrode structure layer to make ohmic contact with the N-type semiconductor layer. However, this design affects the area of ​​the mirror, thus impacting the brightness of the light-emitting element. Summary of the Invention

[0004] In view of the shortcomings of the prior art described above, the object of the present invention is to provide a light-emitting element, comprising: A semiconductor stack includes a first semiconductor layer, an active layer, and a second semiconductor layer stacked sequentially. The semiconductor stack includes a semiconductor platform and an outer periphery surrounding the semiconductor platform. The outer periphery exposes the surface of the first semiconductor layer. The outer periphery includes a first portion and a second portion. The first portion has a first edge, and the second portion has a second edge. The maximum distance between the first edge and the edge of the outer periphery near the light-emitting element is a first distance, and the maximum distance between the second edge and the edge of the outer periphery near the light-emitting element is a second distance. The second distance is greater than the first distance. A second insulating layer is formed on the semiconductor stack. The second insulating layer has a first opening in the second portion of the outer peripheral portion. The first opening includes a first sidewall away from the edge of the light-emitting element and a second sidewall close to the edge of the light-emitting element. A first connection electrode is formed on a semiconductor stack. The first connection electrode includes a portion extending to the outer periphery and contacting the first semiconductor layer through the first opening. The first connection electrode is in contact with the first sidewall and the second sidewall.

[0005] This application also provides another light-emitting element, including: A semiconductor stack includes a first semiconductor layer, an active layer, and a second semiconductor layer stacked sequentially. The semiconductor stack includes a semiconductor platform, a first outer sidewall, an outer peripheral portion surrounding the semiconductor platform, and a second outer sidewall. The outer peripheral portion exposes the surface of the first semiconductor layer. The outer peripheral portion includes a first part and a second part. The first part has a first edge, and the second part has a second edge. The maximum distance between the first edge and the edge of the outer peripheral portion near the light-emitting element is a first distance, and the maximum distance between the second edge and the edge of the outer peripheral portion near the light-emitting element is a second distance. The second distance is greater than the first distance. A first connection electrode is formed on the semiconductor platform and extends to the outer periphery, contacting the first semiconductor layer. The ratio between the distance between the second edge of the outer periphery and the edge of the first connecting electrode and the second distance is greater than or equal to 0.5. Attached Figure Description

[0006] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0007] Figure 1 This is a cross-sectional view of the light-emitting element 1 disclosed in Embodiment 1 of the present invention; Figure 2 This is a top view of a partial area of ​​the light-emitting element 1 in Embodiment 1; Figure 3 for Figure 2 A sectional view taken along line I-I'; Figure 4 This is a cross-sectional view of the light-emitting element 2 disclosed in Embodiment 2 of the present invention; Figure 5 This is a top view of a partial area of ​​the light-emitting element 2 in Embodiment 2; Figure 6 for Figure 5 A sectional view taken along line II-II'; Figure 7 This is a partial cross-sectional view of another embodiment of the present invention. Implementation

[0008] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. The technical features designed in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0009] In the description of this invention, it should be noted that all terms used in this invention (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains, and should not be construed as limiting the invention; it should be further understood that the terms used in this invention should be understood to have the same meaning as those in the context of this specification and in the relevant field, and should not be understood in an idealized or overly formal sense, except as expressly defined in this invention. Example 1

[0010] Figure 1 This is a cross-sectional view of the light-emitting element 1 disclosed in Embodiment 1 of the present invention. Figure 2 This is a top view of a partial area of ​​the light-emitting element 1 in Embodiment 1. Figure 3 for Figure 2 A sectional view taken along line I-I'.

[0011] like Figure 1 As shown, the light-emitting element 1 includes a substrate 10 and a semiconductor stack 20 formed on the substrate 10, wherein the semiconductor stack 20 includes a first semiconductor layer 21, an active layer 22 and a second semiconductor layer 23 stacked sequentially.

[0012] In one embodiment of the present invention, the substrate 10 may be formed using a carrier wafer suitable for semiconductor material growth. Furthermore, the substrate 10 may be formed of a material with excellent thermal conductivity or may be a conductive or insulating substrate. Additionally, the substrate 10 may be formed of a light-transmitting material and may have mechanical strength that does not cause bending of the entire semiconductor stack 20 and allows for effective division into separate chips via scribing and breaking processes. For example, the substrate 10 may use a sapphire (Al2O3) substrate, a silicon carbide (SiC) substrate, a silicon (Si) substrate, a zinc oxide (ZnO) substrate, a gallium nitride (GaN) substrate, a gallium arsenide (GaAs) substrate, or a gallium phosphide (GaP) substrate, etc., with sapphire (Al2O3) substrates being particularly preferred. In this embodiment, the substrate 10 is a sapphire substrate with a series of protrusions on its surface, including, for example, protrusions without a fixed slope formed by dry etching, or protrusions with a fixed slope formed by wet etching.

[0013] In one embodiment of the present invention, a semiconductor stack 20 with photoelectric properties, such as a light-emitting stack, is formed on a substrate 10 by metal-organic chemical vapor deposition (MOCVD), molecular beam epitaxy (MBE), hydride vapor deposition (HVPE), physical vapor deposition (PVD), or ion plating. The physical vapor deposition method includes sputtering or evaporation. The first semiconductor layer 21, the active layer 22, and the second semiconductor layer 23 may be formed from a group III gallium nitride (GaN) series compound semiconductor, such as GaN, AlN, InGaN, AlGaN, InAlGaN, and at least one thereof. The first semiconductor layer 21 is an electron-providing layer and can be formed by implanting an n-type dopant (e.g., Si, Ge, Se, Te, C, etc.). The second semiconductor layer 23 is a hole-providing layer and can be formed by implanting a p-type dopant (e.g., Mg, Zn, Be, Ca, Sr, Ba, etc.). The active layer 22 is a layer in which electrons provided by the first semiconductor layer 21 and holes provided by the second semiconductor layer 23 recombine to output light of a predetermined wavelength. It can be formed from a multilayer semiconductor thin film having a single-layer or multilayer quantum well structure with alternating stacked well and barrier layers. The active layer 22 may be formed with different material compositions or ratios depending on the wavelength of the output light. For example, the emission wavelength of the light-emitting element 1 in this embodiment is between 420 nm and 580 nm. The active layer 22 may be formed as a pair of structures including a well layer and a barrier layer 60 using group III to group V compound semiconductor materials (e.g., at least one of InGaN / GaN, InGaN / InGaN, GaN / AlGaN, InAlGaN / GaN, GaAs(InGaAs) / AlGaAs, or GaP(InGaP) / AlGaP), but this disclosure is not limited thereto. The well layer may be formed from a material having a band gap smaller than that of the barrier layer 60.

[0014] In one embodiment of the present invention, such as Figure 1 and Figure 2As shown, the semiconductor stack 20 can be patterned using photolithography, etching, or other methods to form a semiconductor platform 201, a first outer sidewall 20a, an outer peripheral portion 202, a second outer sidewall 20b, and vias 203, with the outer peripheral portion 203 surrounding the semiconductor platform 201. The semiconductor platform 201 is formed by removing portions of the second semiconductor layer 23 and the active layer 22 to create a structure comprising a first semiconductor layer 21, a second semiconductor layer 23, and an active layer 22. The outer peripheral portion 202 and the vias 203 are formed by removing portions of the second semiconductor layer 23 and the active layer 22 to expose the first surface 21a and the second surface 21b of the first semiconductor layer 21, respectively. The vias 203 can be regularly disposed within the semiconductor stack 20. However, it should be understood that the invention is not limited thereto, and the configuration and number of vias 203 can be varied in various ways. The exposed area of ​​the first semiconductor layer 21 is not limited to a shape corresponding to the shape of the vias 203. For example, the exposed area of ​​the first semiconductor layer 21 can have a linear shape or a combination of holes and lines.

[0015] In one embodiment of the present invention, such as Figure 2 As shown, the outer peripheral portion 202 includes a first portion 2021 and a second portion 2022. The first portion 2021 has a first edge 2021a, and the second portion 2022 has a second edge 2022a. The distance between the first edge 2021a and the edge of the outer peripheral portion 202 near the light-emitting element 1 is a first distance D1, and the distance between the second edge 2022a and the edge of the outer peripheral portion 202 near the light-emitting element 1 is a second distance D2. The second distance D2 is greater than the first distance D1. The side length of the light-emitting element 1 is greater than 35 mil. The first semiconductor layer 21 exposed on the outer peripheral portion 202 needs to be in electrical contact with the first connection electrode 81 described later in order for the light-emitting element 1 to obtain better current spreading capability and lower voltage. However, if the first connecting electrode 81 is in contact with the entire exposed first semiconductor layer 21 on the outer periphery 202, the light-emitting element 1 will lose a large amount of light-emitting area. Therefore, the outer periphery 202 is provided with a first part 2021 and a second part 2022, wherein the second distance D2 is greater than the first distance D1, so that the first connecting electrode 81 can make electrical contact with the first semiconductor layer 21 of the second part 2022, and the first connecting electrode 81 does not make electrical contact with the first semiconductor layer 21 of the first part 2021.

[0016] In one embodiment of the present invention, such as Figures 1 to 3As shown, the first outer sidewall 20a is a sidewall of the second semiconductor layer 23, the active layer 22, and a portion of the first semiconductor layer 21. One end of the first outer sidewall 20a is connected to a surface 23a of the second semiconductor layer 23 (i.e., the surface of the semiconductor platform 201). The first outer sidewall 20a includes a first endpoint 20a1 and a second endpoint 20a2. The first endpoint 20a1 is connected to the surface of the semiconductor platform 201 (the surface 23a of the second semiconductor layer), and the second endpoint 20a2 is connected to the first surface 21a of the first semiconductor layer 21 exposed by the outer periphery 202. The second outer sidewall 20b is a sidewall of a portion of the first semiconductor layer 21. One end of the second outer sidewall 20b is connected to the first surface 21a of the first semiconductor layer exposed by the outer periphery 202, and the other end is connected to the exposed surface of the substrate 10 or to a sidewall of the substrate 10. Figure 1 As shown, the first outer sidewall 20a has an obtuse angle or a right angle with the first surface 21a of the first semiconductor layer 21, and the second outer sidewall 20b has an obtuse angle or a right angle with the surface of the substrate 10.

[0017] In one embodiment of the present invention, such as Figure 1 As shown, a transparent conductive layer 30 is formed on the semiconductor platform 201. The transparent conductive layer 30 is formed on the semiconductor platform 201 by means of physical vapor deposition or chemical vapor deposition, and is in contact with the second semiconductor layer 23. The material of the transparent conductive layer 30 can be ITO, InO, SnO, CTO, ATO, ZnO, GaP, or a combination thereof. The transparent conductive layer 30 can be formed by vapor deposition or sputtering. In this embodiment, the thickness of the transparent conductive layer 30 is selected in the range of 5 nm to 100 nm. Furthermore, it is preferable to select a thickness in the range of 10 nm to 50 nm.

[0018] In one embodiment of the present invention, such as Figure 1 As shown, the light-emitting element 1 includes a first insulating layer 40 formed on the semiconductor stack 20. The first insulating layer 40 may include one or more openings to expose the surface of the transparent conductive layer 30. The first insulating layer 40 may cover a portion of the surface of the transparent conductive layer 30 and a portion of the surface of the semiconductor stack 20. When the first outer sidewall 20a is an inclined sidewall, the first insulating layer 40 disposed on the first outer sidewall 20a can be formed more stably.

[0019] The first insulating layer 40 may include at least one of SiO2, SiN, SiOxNy, TiO2, Si3N4, Al2O3, TiN, AlN, ZrO2, TiAlN, TiSiN, HfO, TaO2, and MgF2. In an example embodiment, the first insulating layer 40 may have a multilayer film structure in which insulating films with different refractive indices are alternately stacked, and may be configured as a distributed Bragg reflector (DBR). The multilayer film structure may be a structure in which first insulating films and second insulating films having a first refractive index and a second refractive index (as different refractive indices) are alternately stacked.

[0020] In one embodiment of the present invention, such as Figure 1 As shown, the light-emitting element 1 includes a reflective layer 50 formed on the first insulating layer 40. The reflective layer 50 can be formed as a single-layer or multi-layer structure of a conductive material having ohmic properties with the transparent conductive layer 30. The reflective layer 50 can be formed of one or more materials and alloys thereof, such as gold (Au), tungsten (W), platinum (Pt), iridium (Ir), silver (Ag), aluminum (Al), copper (Cu), nickel (Ni), titanium (Ti), chromium (Cr), etc. Therefore, the current applied to the reflective layer 50 can diffuse through the transparent electrode layer 30. The reflectivity of the reflective layer 50 for light emitted from the light-emitting element 1 is greater than 70%.

[0021] In one embodiment of the present invention, such as Figure 1 As shown, the light-emitting element 1 also includes a blocking layer 60 formed on the reflective layer 50. The outer edge of the blocking layer 60 covers the tail end of the reflective layer 50, which can prevent the components of the reflective layer 50 (such as silver or aluminum) from diffusing when heated or electrically conductive (such as silver or aluminum). The material of the blocking layer 60 includes metallic materials, such as titanium (Ti), tungsten (W), aluminum (Al), indium (In), tin (Sn), nickel (Ni), platinum (Pt), chromium (Cr), gold (Au), titanium-tungsten (TiW), and alloys of the above materials. The blocking layer 60 can be a single layer or a stacked structure, such as titanium (Ti) / aluminum (Al) and / or titanium (Ti) / tungsten (W).

[0022] In one embodiment, the barrier layer 60 may be omitted.

[0023] In one embodiment of the present invention, such as Figures 1 to 3As shown, the light-emitting element 1 further includes a second insulating layer 70, which is formed on the semiconductor stack 20. The second insulating layer 70 includes a first opening OP1, a second opening OP2, and a third opening OP3. The first opening OP1 is formed on the outer peripheral second portion 2022 to expose the first surface 21a of the first semiconductor layer 21. The second opening OP2 exposes a portion of the surface of the barrier layer 60. The third opening OP3 is formed on the through-hole 203 to expose the second surface 21b of the first semiconductor layer 21. In another embodiment, when the barrier layer 60 is not provided, the second opening OP2 exposes a portion of the surface of the reflective layer 50.

[0024] The material of the second insulating layer 70 can be substantially the same as that of the first insulating layer 40, or it can be different. The second insulating layer 70 can be a single layer or a stacked structure. When the second insulating layer 70 is a single layer, it can protect the sidewalls of the semiconductor stack 20 from damage to the active layer 22 by subsequent fabrication processes. When the second insulating layer 70 is a stacked structure, it can contain two or more materials with different refractive indices stacked alternately to form a Bragg mirror (DBR) structure, selectively reflecting light of a specific wavelength. In one embodiment, the light-emitting element 1 does not have a blocking layer 60, and the second opening OP2 exposes a portion of the surface of the reflective layer 50.

[0025] In one embodiment of the present invention, such as Figures 1 to 3 As shown, the light-emitting element 1 further includes a first connecting electrode 81 and a second connecting electrode 82, which are formed on the second insulating layer 80. The first connecting electrode 81 fills the through-hole 203 and covers the third opening OP3 to contact the second surface 21b of the first semiconductor layer 21, and extends to cover a portion of the surface of the second insulating layer 70, wherein the first connecting electrode 81 is insulated from the second semiconductor layer 23 through the second insulating layer 70. The second connecting electrode 82 covers the second opening OP2 to contact a portion of the barrier layer 60, and extends to cover a portion of the surface of the second insulating layer 70, wherein the second connecting electrode 82 is electrically connected to the second semiconductor layer 23 through the barrier layer 60, and the second connecting electrode 82 and the through-hole 203 do not overlap in the projection direction perpendicular to the semiconductor stack. As shown, Figure 2 and 3As shown, the first opening OP1 also includes a first sidewall OP1a away from the edge of the light-emitting element 1 and a second sidewall OP1b close to the edge of the light-emitting element 1. The first connecting electrode 81 extends partially onto the outer peripheral portion 202 and contacts the first semiconductor layer 21 through the first opening OP1. The first connecting electrode 81 and the first opening OP1 contact the first sidewall OP1a and the second sidewall OP1b, completely covering the first opening OP1. This allows the first connecting electrode 81 to have a larger contact area with the first semiconductor layer 21 of the outer peripheral portion 202, resulting in better current spreading performance. Figure 2 and Figure 3 As shown, the first opening OP1 is located on the outer peripheral portion 202, and the distance between the second sidewall OP1b and the edge of the outer peripheral portion 202 near the light-emitting element 1 is between 1 and 5 μm. By completely covering the first opening OP1, the first connecting electrode 81 can make its projected area on the second part 2022 of the outer peripheral portion 202 greater than 50% of the area of ​​the second part 2022 of the outer peripheral portion 202. Alternatively, the first connecting electrode 81 has an edge 81a near the edge of the light-emitting element 1, and the ratio between the distance between the second edge 2022a of the outer peripheral portion 202 and the edge 81a of the first connecting electrode 81 and the second distance D2 of the outer peripheral portion 202 is greater than or equal to 0.5. This maximizes the area of ​​the first connecting electrode 81, fully leveraging the advantages of the metal structure, such as improving current spreading capability and enhancing the heat dissipation performance of the light-emitting element 1, thereby enhancing the reliability of the light-emitting element 1. The first connecting electrode 81 is made of reflective metal, such as Al or Ag. The larger the projected area on the outer periphery 202, the larger the area of ​​the reflective layer, which greatly helps to improve the brightness of the light-emitting element 1.

[0026] In another embodiment (not shown), the first connecting electrode 81 can further extend to the edge of the light-emitting element 1 onto the surface of the first opening OP1, further increasing the area of ​​the first connecting electrode 81.

[0027] In some embodiments, the first connecting electrode 81 and the second connecting electrode 82 may be a single-layer or stacked structure. The materials of the first connecting electrode 81 and the second connecting electrode 82 include metallic materials, such as chromium (Cr), titanium (Ti), tungsten (W), gold (Au), aluminum (Al), indium (In), silver (Ag), tin (Sn), nickel (Ni), platinum (Pt), and alloys of the above materials.

[0028] In one embodiment of the present invention, such as Figure 1As shown, the light-emitting element 1 also includes a third insulating layer 90, which is formed on the first connecting electrode 81 and the second connecting electrode 82. The third insulating layer 90 includes a fourth opening OP4 and a fifth opening OP5. The fourth opening OP4 exposes a portion of the surface of the first connecting electrode 81, and the fifth opening OP5 exposes a portion of the surface of the second connecting electrode 82.

[0029] In some embodiments, the refractive index of the third insulating layer 90 is greater than 1.4. The third insulating layer 90 may include SiO2, SiN, Al2O3, etc. The third insulating layer 90 may be a multilayer film structure composed of alternating stacked high-refractive-index and low-refractive-index dielectric films, such as a Bragg reflector (DBR). The high-refractive-index dielectric film may be made of TiO2, NB2O5, TA2O5, HfO2, ZrO2, etc.; the low-refractive-index dielectric film may be made of SiO2, MgF2, Al2O5, SiON, etc. The thickness of the third insulating layer 90 is between 500 nm and 1500 nm.

[0030] In one embodiment of the present invention, such as Figure 1 As shown, the light-emitting element 1 also includes a first pad electrode 101 and a second pad electrode 102. The first pad electrode 101 is formed in the fourth opening OP4, and is in contact with the first connecting electrode 81, forming an electrical connection with the first connecting electrode 81. The second pad electrode 102 is formed in the fifth opening OP5, and is in contact with the second connecting electrode 82, forming an electrical connection with the second connecting electrode 82.

[0031] In one embodiment of the present invention, each of the first pad electrode 101 and the second pad electrode 102 may comprise a single film of a single material selected from the group consisting of gold (Au), tin (Sn), nickel (Ni), lead (Pb), silver (Ag), indium (In), chromium (Cr), germanium (Ge), silicon (Si), titanium (Ti), tungsten (W), and platinum (Pt), or an alloy comprising at least two of these materials, or a multilayer structure comprising a combination thereof.

[0032] Each of the first pad electrode 101 and the second pad electrode layer 92 can be used as an external terminal of the light-emitting element 1, but the inventive concept is not limited thereto.

[0033] In another embodiment of the present invention, the materials of the first pad electrode 101 and the second pad electrode 102 include Ti, Al, Ni, Pt, and Au, with the outermost layer being Au. To facilitate the packaging and use of the light-emitting element 1, in some embodiments, a solder layer can be added to the first pad electrode 101 and the second pad electrode 102. This solder layer is a Sn-containing material, such as a Sn-Ag-Cu alloy or a Sn-Sb alloy. The liquid melting point of this solder layer is 200~250℃. The thickness of this solder layer can be 60~100μm to ensure that the light-emitting element 1 has sufficient solder for welding at the packaging end. In some embodiments, the thickness of this solder layer can be 80±10μm. The solder layer facilitates the subsequent die-bonding packaging of the light-emitting element 1 and reduces the risk of leakage. Example 2

[0034] Light-emitting element 2 has a roughly the same structure as light-emitting element 1, therefore for Figures 4-6 The light-emitting element 2 and Figures 1-3 The light-emitting elements 1 have the same name and designation, indicating the same structure, the same material, or the same function. The description will be omitted or will not be repeated here.

[0035] Figure 4 This is a cross-sectional view of the light-emitting element 2 disclosed in Embodiment 2 of the present invention. Figure 5 This is a top view of a partial area of ​​the light-emitting element 2 in Embodiment 2. Figure 6 for Figure 5 A sectional view taken along line II-II'.

[0036] like Figure 4 As shown, the light-emitting element 2 includes a substrate 10 and a semiconductor stack 20 formed on the substrate 10, wherein the semiconductor stack 20 includes a first semiconductor layer 21, an active layer 22 and a second semiconductor layer 23 stacked sequentially.

[0037] In one embodiment of the present invention, such as Figure 4 and Figure 5As shown, the semiconductor stack 20 can be patterned using photolithography, etching, or other methods to form a semiconductor platform 201, a first outer sidewall 20a, an outer peripheral portion 202, a second outer sidewall 20b, and vias 203, with the outer peripheral portion 203 surrounding the semiconductor platform 201. The semiconductor platform 201 is formed by removing portions of the second semiconductor layer 23 and the active layer 22 to create a structure comprising a first semiconductor layer 21, a second semiconductor layer 23, and an active layer 22. The outer peripheral portion 202 and the vias 203 are formed by removing portions of the second semiconductor layer 23 and the active layer 22 to expose the first surface 21a and the second surface 21b of the first semiconductor layer 21, respectively. The vias 203 can be regularly disposed within the semiconductor stack 20. However, it should be understood that the invention is not limited thereto, and the configuration and number of vias 203 can be varied in various ways. The exposed area of ​​the first semiconductor layer 21 is not limited to a shape corresponding to the shape of the vias 203. For example, the exposed area of ​​the first semiconductor layer 21 can have a linear shape or a combination of holes and lines.

[0038] like Figures 4 to 6 As shown, the light-emitting element 2 further includes a second insulating layer 70, which is formed on the semiconductor stack 20. The second insulating layer 70 includes a second opening OP2 and a third opening OP3. The second opening OP2 exposes a portion of the surface of the barrier layer 60, and the third opening OP3 is formed on the through-hole 203 to expose the second surface 21b of the first semiconductor layer 21. In another embodiment, when the barrier layer 60 is not provided, the second opening OP2 exposes a portion of the surface of the reflective layer 50.

[0039] In one embodiment, the second insulating layer 70 further covers the first outer sidewall 20a of the semiconductor stack 20 and a portion of the outer peripheral portion 202 surface. The second insulating layer 70 includes a portion that contacts the first surface 21a of the first semiconductor layer 21 of the outer peripheral portion 202, and a portion of the second insulating layer 70 includes an outer edge 70a located on the outer peripheral portion 202. The first surface 21a of the first semiconductor layer 21 of the outer peripheral portion 202 includes a portion covered by the second insulating layer 70 and a portion not covered by the second insulating layer 70.

[0040] like Figures 4 to 6As shown, the light-emitting element 2 further includes a first connecting electrode 81 and a second connecting electrode 82, which are formed on the second insulating layer 80. The first connecting electrode 81 fills the through-hole 203 and covers the third opening OP3 to contact the second surface 21b of the first semiconductor layer 21, and extends to cover a portion of the surface of the second insulating layer 70, wherein the first connecting electrode 81 is insulated from the second semiconductor layer 23 through the second insulating layer 70. The second connecting electrode 82 covers the second opening OP2 to contact a portion of the barrier layer 60, and extends to cover a portion of the surface of the second insulating layer 70, wherein the second connecting electrode 82 is electrically connected to the second semiconductor layer 23 through the barrier layer 60, and the second connecting electrode 82 and the through-hole 203 do not overlap in the projection direction perpendicular to the semiconductor stack.

[0041] The side length of the light-emitting element 2 is greater than 35mil, and when a large current is applied, the first semiconductor layer 21 exposed on the outer periphery 202 needs to be in continuous contact with the first connecting electrode 81 in order for the light-emitting element 2 to obtain better current expansion capability and lower voltage.

[0042] like Figure 5 and Figure 6 As shown, the first connecting electrode 81 includes an outer edge 70a that partially covers the first insulating layer 70 and extends to the first surface 21a of the first semiconductor layer 21 of the outer peripheral portion 202 not covered by the second insulating layer 70. The projected area of ​​the first connecting electrode 81 on the second portion 2022 of the outer peripheral portion 202 is greater than 50% of the area of ​​the second portion 2022 of the outer peripheral portion 202, or the ratio between the distance between the second edge 2022a of the outer peripheral portion 202 and the distance between the first connecting electrode 81 and the edge of the light-emitting element 1 and the second distance D2 of the outer peripheral portion 202 is greater than 0.5. This maximizes the area of ​​the first connecting electrode 81, fully leveraging the advantages of the metal structure, such as improving current spreading capability and heat dissipation performance of the light-emitting element 1, thereby enhancing the reliability of the light-emitting element 1. The first connecting electrode 81 uses a reflective metal, such as Al or Ag. The larger the projected area on the outer peripheral portion 202, the larger the area of ​​the reflective layer, which greatly helps to improve the brightness of the light-emitting element 1.

[0043] In another embodiment, such as Figure 7As shown, the first connecting electrode 81 can further extend to the second outer wall 20b of the semiconductor stack 20, and the edge 81a of the first connecting electrode 81 is located on the second outer wall 20b of the semiconductor stack 20. This allows the area of ​​the first connecting electrode 81 to be maximized within a reliable range, thereby improving the light extraction efficiency of the light-emitting element 2. That is, the ratio between the distance between the second edge 2022a of the outer periphery 202 and the distance between the first connecting electrode 81 and the edge of the light-emitting element 1 and the second distance D2 of the outer periphery 202 is between 1 and 1.2. If the ratio is greater than 1.2, the first connecting electrode 81 may continue to extend to the bottom of the second outer wall 20b, or even contact the surface of the substrate 10. When the wafer is cleaved to form a single light-emitting element, this may cause edge chipping, reducing the reliability of the light-emitting element 2.

Claims

1. A light-emitting element, comprising: A semiconductor stack includes a first semiconductor layer, an active layer, and a second semiconductor layer stacked sequentially. The semiconductor stack includes a semiconductor platform and an outer periphery surrounding the semiconductor platform. The outer periphery exposes the surface of the first semiconductor layer. The outer periphery includes a first portion and a second portion. The first portion has a first edge, and the second portion has a second edge. The maximum distance between the first edge and the edge of the outer periphery near the light-emitting element is a first distance, and the maximum distance between the second edge and the edge of the outer periphery near the light-emitting element is a second distance. The second distance is greater than the first distance. A second insulating layer is formed on the semiconductor stack. The second insulating layer has a first opening in the second portion of the outer peripheral portion. The first opening includes a first sidewall away from the edge of the light-emitting element and a second sidewall close to the edge of the light-emitting element. A first connection electrode is formed on a semiconductor stack. The first connection electrode includes a portion extending to the outer periphery and contacting the first semiconductor layer through the first opening. The first connection electrode is in contact with the first sidewall and the second sidewall.

2. The light-emitting element according to claim 1, characterized in that, The projected area of ​​the first connecting electrode on the second part of the outer periphery accounts for more than 50% of the area of ​​the second part of the outer periphery.

3. The light-emitting element according to claim 1, characterized in that, The first connecting electrode has an edge close to the light-emitting element, and the edge of the first connecting electrode is located on the outer periphery.

4. The light-emitting element according to claim 3, characterized in that, The ratio between the distance between the second edge of the outer periphery and the edge of the first connecting electrode and the second distance is greater than or equal to 0.

5.

5. The light-emitting element according to claim 1, characterized in that, The first connecting electrode contains Al or Ag.

6. The light-emitting element according to claim 1, characterized in that, The distance between the second outer wall of the first opening and the outer periphery near the edge of the light-emitting element is between 1 and 5 μm.

7. The light-emitting element according to claim 1, characterized in that, The first connecting electrode also includes a portion extending onto the surface of the first opening.

8. A light-emitting element, comprising: A semiconductor stack includes a first semiconductor layer, an active layer, and a second semiconductor layer stacked sequentially. The semiconductor stack includes a semiconductor platform, a first outer sidewall, an outer peripheral portion surrounding the semiconductor platform, and a second outer sidewall. The outer peripheral portion exposes the surface of the first semiconductor layer. The outer peripheral portion includes a first part and a second part. The first part has a first edge, and the second part has a second edge. The maximum distance between the first edge and the edge of the outer peripheral portion near the light-emitting element is a first distance, and the maximum distance between the second edge and the edge of the outer peripheral portion near the light-emitting element is a second distance. The second distance is greater than the first distance. A first connection electrode is formed on the semiconductor platform and extends to the outer periphery, contacting the first semiconductor layer. The ratio between the distance between the second edge of the outer periphery and the edge of the first connecting electrode and the second distance is greater than or equal to 0.

5.

9. The light-emitting element according to claim 8, characterized in that, The projected area of ​​the first connecting electrode on the second part of the outer periphery accounts for more than 50% of the area of ​​the second part of the outer periphery.

10. The light-emitting element according to claim 8, characterized in that, The first connecting electrode also includes a portion extending to the top of the second outer sidewall.

11. The light-emitting element according to claim 10, characterized in that, The ratio between the distance between the second edge of the outer periphery and the edge of the first connecting electrode and the second distance is greater than or equal to 1 to 1.

2.

12. The light-emitting element according to claim 8, characterized in that, It also includes an insulating layer formed between the semiconductor stack and the first connecting electrode, wherein a portion of the insulating layer covers the first outer sidewall of the semiconductor stack and a portion of the exposed surface of the first semiconductor layer on the outer periphery, and a portion of the outer periphery surface is not covered by the insulating layer.

13. The light-emitting element according to claim 12, characterized in that, The insulating layer includes a portion that contacts the outer periphery, and the portion of the insulating layer includes an outer edge located on the outer periphery.

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