Light emitting diode and light emitting device

Abstract

The present application relates to the technical field of semiconductor manufacturing, in particular to a light emitting diode, which comprises an epitaxial stack, the epitaxial stack has opposite upper and lower surfaces, and the epitaxial stack comprises a first semiconductor layer, a light emitting layer and a second semiconductor layer in sequence along the direction from the upper surface to the lower surface; the epitaxial stack has a first epitaxial sidewall and a second epitaxial sidewall on the same side, the first epitaxial sidewall is a part of the sidewall on the first semiconductor layer, the second epitaxial sidewall is a part of the sidewall of the second semiconductor layer extending to the upper surface of the epitaxial stack, extending through the sidewall of the light emitting layer and extending to the sidewall of the first semiconductor layer, the first epitaxial sidewall is connected to the second epitaxial sidewall, a turning point is formed at the connection of the first epitaxial sidewall and the second epitaxial sidewall, and an included angle is formed at the turning point, the included angle is greater than 90 degrees. By means of the arrangement, the residual organic matter at the cutting path can be effectively avoided, and the light emitting characteristics of the light emitting diode can be effectively improved.

Description

Technical Field

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

[0002] A light-emitting diode (LED) is a semiconductor light-emitting element, typically made of semiconductors such as GaN, GaAs, GaP, and GaAsP. Its core is a PN junction that emits light. LEDs possess advantages such as high luminous intensity, high efficiency, small size, and long lifespan, and are considered one of the most promising light sources available today. LEDs are widely used in lighting, monitoring and command systems, high-definition broadcasting, high-end cinemas, office displays, interactive conferencing, virtual reality, and other fields.

[0003] Currently, LED chip manufacturing typically involves multiple photolithography and resist removal processes. It is difficult to completely remove the photoresist from the dicing areas of the LED chip. (Reference...) Figure 7 As shown, especially at the junction of the outer sidewall of the worktable and the cutting channel, the near right angle makes it difficult to remove, easily leaving organic residue. When the LED is powered on, this location often experiences leakage or even burns. Therefore, how to solve this problem has long been a technical challenge for those skilled in the art.

[0004] It should be noted that the information disclosed in this background section is intended only to enhance the understanding of the overall background of the present invention, and should not be construed as an admission or in any way implying that such information constitutes knowledge already known to those skilled in the art.

[0005] Known existing technologies. Summary of the Invention

[0006] This invention provides a light-emitting diode (LED) comprising an epitaxial stack having opposing upper and lower surfaces. The epitaxial stack sequentially includes a first semiconductor layer, a light-emitting layer, and a second semiconductor layer along the direction from the upper to the lower surface. The epitaxial stack has a first epitaxial sidewall and a second epitaxial sidewall on the same side. The first epitaxial sidewall is a portion of the sidewall on the first semiconductor layer. The second epitaxial sidewall extends from a portion of the sidewall of the second semiconductor layer toward the upper surface of the epitaxial stack, passing through the sidewall of the light-emitting layer and extending to the sidewall of the first semiconductor layer. The first epitaxial sidewall connects to the second epitaxial sidewall. An inflection point is formed at the junction of the first and second epitaxial sidewalls, and an included angle > 90° is formed at the inflection point.

[0007] The present invention also provides a light-emitting diode, comprising an epitaxial stack and a protective layer. The epitaxial stack has opposing upper and lower surfaces, and sequentially includes a first semiconductor layer, a light-emitting layer, and a second semiconductor layer along the direction from the upper surface to the lower surface. The protective layer is disposed outside the epitaxial stack and covers a portion of the sidewalls of the epitaxial stack. The outermost portion of the protective layer is defined as the protective layer sidewall. The protective layer sidewall has an inflection point at the height of the first semiconductor layer. The inflection point extends towards the upper surface of the epitaxial stack to form a first protective sidewall, and extends towards the lower surface of the epitaxial stack to form a second protective sidewall. The first and second protective sidewalls form an angle at the inflection point, and the angle is greater than 90°.

[0008] The present invention also provides a light-emitting device, which includes a light-emitting diode, wherein the light-emitting diode is any of the light-emitting diodes described above.

[0009] The present invention provides a light-emitting diode and a light-emitting device, which forms two inclined sidewalls by setting an inflection point. The inflection point is located on the sidewall of the first semiconductor layer. Due to the inflection point's inclination angle, it is easier to clean organic matter during the adhesive removal process after chip dicing. It also facilitates the continuity of subsequent protective layers covering these sidewalls. Furthermore, since the inflection point is located on the first semiconductor layer, the light-emitting layer and the second semiconductor layer are not exposed. This avoids leakage and burn problems even if some organic matter remains. It also ensures that the light-emitting layer has a flat surface that is not prone to organic matter residue, thereby reducing the risk of leakage.

[0010] Other features and advantages of the present invention will be set forth in the following description, and some of the technical features and advantages may be apparent from the description or learned by practicing the invention. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, some of the drawings in the following description are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is a schematic diagram of the structure of the light-emitting diode provided in the first embodiment of the present invention;

[0013] Figure 2 yes Figure 1 A schematic diagram of the structure at the epitaxial layer in the middle;

[0014] Figure 3 yes Figure 2A magnified view of a portion of the image;

[0015] Figure 4 This is a schematic diagram of the structure of a light-emitting diode provided in the second embodiment of the present invention;

[0016] Figure 5 yes Figure 4 A magnified view of a portion of the image;

[0017] Figure 6 This is a schematic diagram of the structure of a light-emitting diode provided in the third embodiment of the present invention;

[0018] Figure 7 This is a schematic diagram of the structure of a traditional light-emitting diode.

[0019] Figure label:

[0020] 10-Epiaxial stack; 101-Upper surface; 102-Lower surface; 103-First semiconductor layer; 104-Light-emitting layer; 105-Second semiconductor layer; 12-Protective layer; 14-First electrode; 16-Dielectric layer; 18-Metal reflective layer; 20-Bonding layer; 22-Substrate; 24-Second electrode; 26-Current diffusion layer; 31-First epitaxial sidewall; 32-Second epitaxial sidewall; 40-Protective layer sidewall; 41-First protective sidewall; 42-Second protective sidewall; A-Inflection point; B-Included angle; d1-Distance from inflection point to upper surface of light-emitting layer; H1-Thickness of first semiconductor layer; W1-Vertical projection length. Detailed Implementation

[0021] 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.

[0022] In the description of this invention, it should be understood that the terms "center," "lateral," "upper," "lower," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more. Additionally, the term "comprising" and any variations thereof mean "at least comprising."

[0023] Please see Figure 1 , Figure 2 and Figure 3 , Figure 1 This is a schematic diagram of the structure of the light-emitting diode provided in the first embodiment of the present invention. Figure 2 yes Figure 1 A schematic diagram of the structure at 10 points of the epitaxial stack. Figure 3 yes Figure 2 A partially enlarged schematic diagram is shown. To achieve at least one or more of the aforementioned advantages, a first embodiment of the present invention provides a light-emitting diode. As shown, the light-emitting diode includes an epitaxial stack 10.

[0024] The epitaxial stack 10 has an upper surface 101 and a lower surface 102 opposite to each other. The epitaxial stack 10 includes a first semiconductor layer 103, a light-emitting layer 104 and a second semiconductor layer 105 in sequence along the direction from the upper surface 101 to the lower surface 102.

[0025] Optionally, the aforementioned epitaxial stack 10 can be formed on the growth substrate by physical vapor deposition (PVD), chemical vapor deposition (CVD), epitaxy growth technology, or atomic layer deposition (ALD). The first semiconductor layer 103 and the second semiconductor layer 105 are semiconductors with different conductivity types, electrical properties, and polarities, depending on the doped elements to provide electrons or holes; for example, when the first semiconductor layer 103 is n-type, the second semiconductor layer 105 is p-type, and the light-emitting layer 104 is formed between the first semiconductor layer 103 and the second semiconductor layer 105. Electrons and holes recombine in the light-emitting layer 104 under the drive of a current, converting electrical energy into light energy to emit light. The wavelength of the light emitted by the light-emitting diode can be adjusted by changing the physical and chemical composition of one or more layers of the epitaxial light-emitting layer 104; and vice versa. In this embodiment, a light-emitting diode with the first semiconductor layer 103 being n-type and the second semiconductor layer 105 being p-type is used as an example.

[0026] The light-emitting layer 104 provides the region for electron-hole recombination and light radiation. Different materials can be selected depending on the emission wavelength. The light-emitting layer 104 can be a single heterostructure (SH), a double heterostructure (DH), a double-sided double heterostructure (DDH), or a multi-quantum well (MQW). The light-emitting layer 104 includes a well layer and a barrier layer, wherein the barrier layer has a larger band gap than the well layer. By adjusting the composition ratio of the semiconductor material in the light-emitting layer 104, it is desired to radiate light of different wavelengths. In this embodiment, the semiconductor epitaxial stack 100 is a semiconductor material layer capable of radiating ultraviolet, blue, green, yellow, red, and infrared light, specifically a material in the 200nm-950nm range, such as common nitrides, specifically a gallium nitride-based semiconductor epitaxial stack 100. Gallium nitride-based epitaxial stacks are commonly doped with elements such as aluminum and indium, mainly providing radiation in the 200-550nm wavelength band; or common aluminum gallium indium phosphide-based or aluminum gallium arsenide-based semiconductor epitaxial stacks 100, mainly providing radiation in the 550-950nm wavelength band. To improve luminous efficiency, this can be achieved by changing the depth of the quantum wells, the number of paired quantum wells and quantum barriers, the thickness, and / or other characteristics in the light-emitting layer 104. In this embodiment, the semiconductor epitaxial stack 10 is preferably composed of AlGaInP-based or GaAs-based materials.

[0027] As shown in the figure, the epitaxial stack 10 has a first epitaxial sidewall 31 and a second epitaxial sidewall 32 on the same side. The figure uses the first epitaxial sidewall 31 and the second epitaxial sidewall 32 on the left side as examples. The first epitaxial sidewall 31 is a portion of the sidewall of the first semiconductor layer 103. The second epitaxial sidewall 32 extends from a portion of the sidewall of the second semiconductor layer 105 towards the upper surface 101 of the epitaxial stack 10, passing through the sidewall of the light-emitting layer 104 until it reaches the sidewall of the first semiconductor layer 103. In other words, the second epitaxial sidewall 32 is substantially composed of a portion of the sidewall of the second semiconductor layer 105, the sidewall of the light-emitting layer 104, and a portion of the sidewall of the first semiconductor layer 103. Furthermore, the first epitaxial sidewall 31 connects to the second epitaxial sidewall 32, and a bend point A is formed at the connection between the first epitaxial sidewall 31 and the second epitaxial sidewall 32, with an included angle B at this bend point A, where the included angle B > 90°. Compared to... Figure 7 Compared to the traditional right-angled L-shaped sidewall, this invention forms an inclined two-section sidewall by setting an inflection point A. This inflection point A is located on the sidewall of the first semiconductor layer 103 above the light-emitting layer 104. This makes it easier to clean organic matter during the adhesive removal process after chip dicing, and also facilitates the continuity of subsequent protective layers covering the sidewall. Furthermore, since the inflection point A is located at the first semiconductor layer 103, part of the first semiconductor layer 103 is retained to shield the light-emitting layer 104 below, without exposing the light-emitting layer 104 and the second semiconductor layer 105. In this way, even if some organic matter remains at the inflection point, it will accumulate in the first semiconductor layer 103, avoiding the problem of leakage and burns. It also ensures that the light-emitting layer 104 has a flat surface, making it less likely for organic matter to remain, thereby reducing the risk of leakage. Optionally, the first epitaxial sidewall 31 is the portion extending from the upper surface 101 of the epitaxial stack 10 to the lower surface 102 of the epitaxial stack 10 to the inflection point A, where the inflection point A is located on the sidewall of the first semiconductor layer 103. Optionally, considering the influence of light emission effect, the included angle B can be in the range of 91°~120°.

[0028] In some embodiments, the distance from the inflection point A to the upper surface of the light-emitting layer 104 is defined as d1, and the thickness of the first semiconductor layer 103 is H1, where 0.05H1≤d1≤0.4H1. If d1 is less than 0.05H1, it means that the inflection point A is too close to the light-emitting layer 104, and organic matter may still adhere to the vicinity of the light-emitting layer 104, which can easily lead to leakage problems; if d1 is greater than 0.4H1, it means that the inflection point A is too high, resulting in a narrow dicing track, which is not conducive to subsequent process implementation.

[0029] In some embodiments, with the upper surface 101 of the epitaxial stack 10 as the reference plane, the angle between the extension line of the first epitaxial sidewall 31 and the upper surface 101 of the epitaxial stack 10 is 80° to 100°. In the illustrated embodiment, this angle is 90°, that is, the first epitaxial sidewall 31 is perpendicular to the upper surface 101 of the epitaxial stack 10.

[0030] In some embodiments, the vertical projection length W1 of the second epitaxial sidewall 32 located on one side of the epitaxial stack 10 onto the lower surface 102 of the epitaxial stack 10 ranges from 10 to 30 μm, that is, the overall width W1 of the second epitaxial sidewall 32 in the horizontal direction is 10 to 30 μm. Conversely, if it is greater than 30 μm, the remaining light-emitting layer is too small 104, which is not conducive to the light-emitting efficiency; if it is less than 10 μm, the dicing channel is too narrow, which is not conducive to the subsequent dicing process.

[0031] In some embodiments, the light-emitting diode further includes a protective layer 12, a first electrode 14, a dielectric layer 16, a metal reflective layer 18, a bonding layer 20, a substrate 22, and a second electrode 24.

[0032] The protective layer 12 covers the first epitaxial sidewall 31 and the second epitaxial sidewall 32 of the epitaxial stack 10, mainly serving a protective and insulating function. The material of the protective layer 12 may include silicon oxide, etc. The sidewall morphology of the protective layer 12 may be the same as the morphology after the first epitaxial sidewall 31 is connected to the second epitaxial sidewall 32. Since the sidewall morphology of the protective layer 12 matches the morphology of the epitaxial stack 10, the coverage is better. Therefore, as a protective layer, the protective layer 12 can better protect the chip.

[0033] The first electrode 14 is disposed on the upper surface 101 of the epitaxial stack 10. The first electrode 14 can be a single-layer structure, a double-layer structure, or a multi-layer structure. The first electrode 14 can be made of metallic materials, such as Cr, Pt, Au, Ni, Ti, Al, etc., or in a stack.

[0034] A dielectric layer 16 is disposed on the lower surface 102 of the epitaxial stack 10. The dielectric layer 16 has multiple conductive vias connected to the epitaxial stack 10. The dielectric layer 16 is light-transmitting. The material of the dielectric layer 16 may include transparent compounds such as silicon nitride, silicon oxide, and titanium oxide, as well as their stacked combinations. For example, it may be a Bragg mirror (DBR) formed by repeatedly stacking two materials with different refractive indices.

[0035] A metal reflective layer 18 is disposed on the side of the dielectric layer 16 away from the epitaxial stack 10, and the metal reflective layer 18 is connected to the epitaxial stack 10 through vias. The metal reflective layer 18 can be made of a metal. The metal reflective layer 18 can have a reflectivity of more than 90%, and can be formed of a metal or alloy containing at least one of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Ti, Cr, Zn, Pt, Au, and Hf. This metal reflective layer 18 can reflect light radiated from the epitaxial stack 10 toward the substrate 22 back to the epitaxial stack 10 and radiate it out from the light-emitting surface side.

[0036] The bonding layer 20 is disposed on the side of the metal reflective layer 18 away from the epitaxial stack 10. The bonding layer 20 is used to bond the substrate 22 and the epitaxial stack 10, improving the overall structural connection strength. The bonding layer 20 can be made of metal elements such as gold, tin, titanium, tungsten, nickel, platinum, indium, etc., and can be a single-layer structure or a multi-layer structure, or a combination of various materials.

[0037] The substrate 22 is disposed on the side of the bonding layer 20 away from the epitaxial stack 10. The substrate 22 is a conductive substrate, which can be silicon, silicon carbide, or a metal substrate, preferably copper, tungsten, copper-tungsten, or molybdenum substrates. In order to support the epitaxial stack 10 with sufficient mechanical strength, the thickness of the substrate 22 can be 50 μm or more.

[0038] The second electrode 24 is disposed on the side of the substrate 22 away from the epitaxial stack 10. The second electrode 24 can be made of a metallic material.

[0039] In some embodiments, a current diffusion layer 26 may be disposed below the second semiconductor layer 105. The current diffusion layer 26 serves to diffuse current. The material of the current diffusion layer 26 may include gallium phosphide, etc. Furthermore, the current diffusion layer 26 may be patterned to further diffuse the current. The dielectric layer 16 covers the current diffusion layer 26, and the current diffusion layer 26 is exposed in the vias of the dielectric layer 16. The metal reflective layer 18 is electrically connected to the current diffusion layer 26 through the vias.

[0040] Please see Figure 4 and Figure 5 , Figure 4 This is a schematic diagram of the structure of a light-emitting diode provided in the second embodiment of the present invention. Figure 5 yes Figure 4 A partially enlarged schematic diagram is shown. To achieve at least one or more of the aforementioned advantages, a second embodiment of the present invention provides a light-emitting diode. As shown, the light-emitting diode may include a substrate 22, an epitaxial stack 10, and a protective layer 12.

[0041] An epitaxial stack 10 is disposed on a substrate 22, and other structural layers may be disposed between the epitaxial stack 10 and the substrate 22. The epitaxial stack 10 has an upper surface 101 and a lower surface 102 opposite to each other, and the epitaxial stack 10 includes a first semiconductor layer 103, a light-emitting layer 104 and a second semiconductor layer 105 in sequence along the direction from the upper surface 101 to the lower surface 102.

[0042] A protective layer 12 is disposed outside the epitaxial stack 10 and covers a portion of the sidewalls of the epitaxial stack 10. The outermost portion of the protective layer 12 is defined as the protective layer sidewall 40. The protective layer sidewall 40 has an inflection point A at the height of the first semiconductor. The inflection point A extends a portion toward the upper surface 101 of the epitaxial stack 10 to form a first protective sidewall 41, and the inflection point A extends a portion toward the lower surface 102 of the epitaxial stack 10 to form a second protective sidewall 42. The first protective sidewall 41 and the second protective sidewall 42 form an angle B at the inflection point A, where the angle B > 90°. Compared to the traditional right-angled L-shaped sidewall, this invention forms an inclined two-segment sidewall by setting an inflection point A. This inflection point A is located on the sidewall of the protective layer 12, which is horizontally above the light-emitting layer 104. This makes it easier to clean organic matter during the resist removal process after chip dicing, and also improves the continuity of the protective layer 12 covering the epitaxial stack 10. Furthermore, since the inflection point A is located above the light-emitting layer 104, the light-emitting layer 104 and the second semiconductor layer 105 are not exposed. This avoids leakage and burn problems even if some organic matter remains, and ensures that the light-emitting layer 104 has a flat surface that is less prone to organic matter residue, thereby reducing the risk of leakage. Optionally, the included angle B ranges from 91° to 120°.

[0043] The protective layer 12 can refer to the outermost structure of the chip before packaging. In some embodiments, the protective layer 12 can be a single-layer structure or a multi-layer structure. For example, when it is a single-layer structure, it can be a passivation layer, and when it is a multi-layer structure, it can be a DBR reflective structure.

[0044] In some embodiments, the point furthest from inflection point A on the first protective sidewall 41 is the highest point of the first protective sidewall 41. The horizontal height of the highest point of the first protective sidewall 41 is not lower than the height of the upper surface 101 of the epitaxial stack 10. In some embodiments, the first protective sidewall 41 (as shown in the protective layer 12) covers beyond the epitaxial stack 10. The point furthest from inflection point A on the second protective sidewall 42 is the lowest point of the second protective sidewall 42, and the horizontal height of the lowest point of the second protective sidewall 42 is not higher than the height of the lower surface 102 of the epitaxial stack 10. That is, the second protective sidewall 42 extends downward at least to the lower surface 102 of the epitaxial stack 10, and may further extend downward to the edge of the substrate 22.

[0045] With the upper surface 101 of the epitaxial stack 10 as the reference plane, the angle between the extension line of the first protective sidewall 41 and the upper surface 101 of the epitaxial stack 10 is 80°~100°.

[0046] In some embodiments, the light-emitting diode further includes a protective layer 12, a first electrode 14, a dielectric layer 16, a metal reflective layer 18, a bonding layer 20, and a second electrode 24.

[0047] The protective layer 12 covers the epitaxial stack 10. The sidewall morphology of the protective layer 12 may be the same as that of a portion of the protective layer sidewall 40.

[0048] The first electrode 14 is disposed on the upper surface 101 of the epitaxial stack 10. The first electrode 14 can be a single-layer structure, a double-layer structure, or a multi-layer structure. The first electrode 14 can be made of metallic materials, such as Cr, Pt, Au, Ni, Ti, Al, etc.

[0049] A dielectric layer 16 is disposed on the lower surface 102 of the epitaxial stack 10. The dielectric layer 16 has multiple through holes that expose the epitaxial stack 10. The dielectric layer 16 is light-transmitting.

[0050] A metal reflective layer 18 is disposed on the side of the dielectric layer 16 away from the epitaxial stack 10, and the metal reflective layer 18 is connected to the epitaxial stack 10 through vias. The metal reflective layer 18 can be fabricated using a metal material with high reflectivity. In some embodiments, a current diffusion layer 26 may also be disposed below the second semiconductor layer 105. The current diffusion layer 26 serves to diffuse current, and the material of the current diffusion layer 26 may include gallium phosphide, etc. The dielectric layer 16 covers the current diffusion layer 26, and the current diffusion layer 26 is exposed in the vias of the dielectric layer 16. The metal reflective layer 18 is electrically connected to the current diffusion layer 26 through the vias.

[0051] The bonding layer 20 is disposed on the side of the metal reflective layer 18 away from the epitaxial stack 10. The bonding layer 20 is used to bond the substrate 22 and the metal reflective layer 18, improving the overall structural connection strength. The bonding layer 20 can be made of metal elements such as gold, tin, titanium, tungsten, nickel, platinum, indium, etc., and can be a single-layer structure or a multi-layer structure, or a combination of various materials.

[0052] The substrate 22 is disposed on the side of the bonding layer 20 away from the epitaxial stack 10.

[0053] The second electrode 24 is disposed on the side of the substrate 22 away from the epitaxial stack 10.

[0054] Please see Figure 6 , Figure 6 This is a schematic diagram of the structure of a light-emitting diode provided in the third embodiment of the present invention. Compared to Figure 1The main difference in this embodiment for the light-emitting diode is that the second epitaxial sidewall 32 extends at least through the entire second semiconductor layer 105. For example, the second epitaxial sidewall 32 may also extend downward to the underlying dielectric layer 16, etc.

[0055] An embodiment of the present invention also provides a light-emitting device, which includes a light-emitting diode, wherein the light-emitting diode may be the light-emitting diode described in any of the above embodiments.

[0056] In summary, an embodiment of the present invention provides a light-emitting diode and a light-emitting device that, by setting an inflection point A, forms two inclined sidewalls, and this inflection point A is located on the sidewall of the first semiconductor layer 103, makes it easier to clean organic matter during the adhesive removal process after the chip is cut. It also facilitates the continuity of subsequent protective layers covering these sidewalls. Furthermore, since the inflection point A is located at the first semiconductor layer 103, the light-emitting layer 104 and the second semiconductor layer 105 are not exposed. This avoids leakage and burn problems even if some organic matter remains, and also ensures that the light-emitting layer 104 has a flat surface that is not prone to organic matter residue, thereby reducing the risk of leakage.

[0057] Furthermore, those skilled in the art should understand that although many problems exist in the prior art, each embodiment or technical solution of the present invention can be improved in only one or a few aspects, without necessarily solving all the technical problems listed in the prior art or the background art simultaneously. Those skilled in the art should understand that any content not mentioned in a claim should not be construed as a limitation on that claim.

[0058] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A light-emitting diode, characterized in that: The light-emitting diode includes: An epitaxial stack has opposing upper and lower surfaces, wherein the epitaxial stack sequentially comprises a first semiconductor layer, a light-emitting layer, and a second semiconductor layer along the direction from the upper surface to the lower surface; The epitaxial stack has a first epitaxial sidewall and a second epitaxial sidewall on the same side. The first epitaxial sidewall is a portion of the sidewall of the first semiconductor layer. The second epitaxial sidewall extends from the portion of the sidewall of the second semiconductor layer toward the upper surface of the epitaxial stack, through the sidewall of the light-emitting layer, and extends to the sidewall of the first semiconductor layer. The first epitaxial sidewall connects to the second epitaxial sidewall. An inflection point is formed at the connection between the first epitaxial sidewall and the second epitaxial sidewall, and an included angle is formed at the inflection point, wherein the included angle is greater than 90°. The light-emitting diode further includes a first electrode, a dielectric layer, a metal reflective layer, a bonding layer, a substrate, and a second electrode. The first electrode is disposed on the upper surface of the epitaxial stack, the dielectric layer is disposed on the lower surface of the epitaxial stack, the dielectric layer has a plurality of vias, the metal reflective layer is disposed on the side of the dielectric layer away from the epitaxial stack, the metal reflective layer is electrically connected to the epitaxial stack through the vias, the bonding layer is disposed on the side of the metal reflective layer away from the epitaxial stack, and the substrate is disposed on the side of the bonding layer away from the epitaxial stack.

2. The light-emitting diode according to claim 1, characterized in that: The first epitaxial sidewall is the portion extending from the upper surface of the epitaxial stack to the lower surface of the epitaxial stack to the inflection point, where the inflection point is located on the sidewall of the first semiconductor layer.

3. The light-emitting diode according to claim 1, characterized in that: The included angle ranges from 91° to 120°.

4. The light-emitting diode according to claim 1, characterized in that: The distance from the inflection point to the upper surface of the light-emitting layer is defined as d1, and the thickness of the first semiconductor layer is H1, where 0.05H1≤d1≤0.4H1.

5. The light-emitting diode according to claim 1, characterized in that: With the upper surface of the epitaxial stack as the reference plane, the angle between the extension line of the first epitaxial sidewall and the upper surface of the epitaxial stack is 80°~100°.

6. The light-emitting diode according to claim 1, characterized in that: The vertical projection length of the second epitaxial sidewall located on one side of the epitaxial stack on the lower surface of the epitaxial stack ranges from 10 to 30 μm.

7. The light-emitting diode according to claim 1, characterized in that: A current diffusion layer is also disposed below the second semiconductor layer.

8. The light-emitting diode according to claim 1, characterized in that: The light-emitting diode further includes a protective layer that covers the first epitaxial sidewall and the second epitaxial sidewall of the epitaxial stack.

9. The light-emitting diode according to claim 1, characterized in that: The second epitaxial sidewall extends at least across the entire second semiconductor layer.

10. A light-emitting diode, characterized in that: The light-emitting diode includes: An epitaxial stack having opposing upper and lower surfaces, the epitaxial stack comprising, sequentially along the direction from the upper surface to the lower surface, a first semiconductor layer, a light-emitting layer, and a second semiconductor layer; A protective layer is disposed on the outside of the epitaxial stack and covers part of the sidewall of the epitaxial stack; Wherein, the outermost part of the protective layer is defined as the protective layer sidewall. The protective layer sidewall has an inflection point at the height position of the first semiconductor. The inflection point extends a portion toward the upper surface of the epitaxial stack to form a first protective sidewall. The inflection point extends a portion toward the lower surface of the epitaxial stack to form a second protective sidewall. The first protective sidewall and the second protective sidewall form an angle at the inflection point, and the angle is >90°. The light-emitting diode further includes a first electrode, a dielectric layer, a metal reflective layer, a bonding layer, a substrate, and a second electrode. The first electrode is disposed on the upper surface of the epitaxial stack, the dielectric layer is disposed on the lower surface of the epitaxial stack, the dielectric layer has a plurality of vias, the metal reflective layer is disposed on the side of the dielectric layer away from the epitaxial stack, the metal reflective layer is electrically connected to the epitaxial stack through the vias, the bonding layer is disposed on the side of the metal reflective layer away from the epitaxial stack, and the substrate is disposed on the side of the bonding layer away from the epitaxial stack.

11. The light-emitting diode according to claim 10, characterized in that: The included angle ranges from 91° to 120°.

12. The light-emitting diode according to claim 10, characterized in that: The protective layer can be a single-layer structure or a multi-layer structure.

13. The light-emitting diode according to claim 10, characterized in that: The point furthest from the inflection point of the first protective sidewall is the highest point of the first protective sidewall, and the horizontal height of the highest point of the first protective sidewall is not lower than the height of the upper surface of the epitaxial layer.

14. The light-emitting diode according to claim 10, characterized in that: The point furthest from the inflection point of the second protective sidewall is the lowest point of the second protective sidewall, and the horizontal height of the lowest point of the second protective sidewall is not higher than the height of the lower surface of the epitaxial layer.

15. The light-emitting diode according to claim 10, characterized in that: The distance from the inflection point to the upper surface of the light-emitting layer is d1, and the thickness of the first semiconductor layer is H1, where 0.05H1≤d1≤0.4H1.

16. The light-emitting diode according to claim 10, characterized in that: With the upper surface of the epitaxial layer as the reference plane, the angle between the extension line of the first protective sidewall and the upper surface of the epitaxial layer is 80°~100°.

17. A light-emitting device, characterized in that: The light-emitting device includes a light-emitting diode, and the light-emitting diode is the light-emitting diode as described in any one of claims 1 to 16.

Images