Light-emitting diode side face repairing method and light-emitting diode

Abstract

The invention discloses a side face repairing method of a light-emitting diode and the light-emitting diode, and the method comprises the steps: forming a first annular groove and a plurality of first grooves in the upper surface of the light-emitting diode, and enabling the plurality of first grooves to be connected with the first annular groove, a second annular groove and a plurality of second grooves are formed in the lower surface of the light-emitting diode, the second grooves are connected with the second annular groove, a plurality of third V-shaped grooves are formed in the side face of the light-emitting diode, and each third V-shaped groove is connected with one corresponding first groove and one corresponding second groove. In the subsequent forming process of the first inorganic passivation layer, the second organic passivation layer and the third inorganic passivation layer, part of the first inorganic passivation layer, part of the second organic passivation layer and part of the third inorganic passivation layer are embedded into the grooves, and stripping of the passivation layers can be effectively avoided.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor light emitting technology, and in particular to a side repair method of a light emitting diode and a light emitting diode. Background Art

[0002] The core of a light-emitting diode (LED) is the PN junction, which is formed by combining a P-type semiconductor and an N-type semiconductor. P-type semiconductors contain a large number of positively charged holes, while N-type semiconductors contain a large number of negatively charged electrons. When a forward voltage is applied to the PN junction, the holes in the P region diffuse toward the N region, and the electrons in the N region diffuse toward the P region, recombining near the PN junction. When electrons transition from a high energy level to a low energy level, they release energy in the form of photons, resulting in luminescence. The color of the luminescence depends on the band gap width of the semiconductor material. Materials with different band gaps emit light of different wavelengths, resulting in different colors. In the current LED manufacturing process, LED chips are typically formed through a cutting process. However, this process can easily damage the sidewalls of the LED chip. Improving the lateral stability of the LED chip has attracted widespread attention. Summary of the Invention

[0003] In order to solve the above problems in the prior art, the present application provides a side repair method of a light emitting diode and a light emitting diode.

[0004] To achieve the above object, the technical solution adopted by the present invention is: An embodiment of the present application provides a method for repairing a side surface of a light-emitting diode, the method comprising the following steps: A light emitting diode is provided. The light emitting diode includes a back metal layer, a substrate, an epitaxial functional layer, a transparent conductive layer and a surface electrode.

[0005] A first annular groove and a plurality of first grooves are formed on the upper surface of the light-emitting diode, and the plurality of first grooves are connected to each other. A second annular groove and a plurality of second grooves are formed on the lower surface of the light-emitting diode, and the plurality of second grooves are connected to each other.

[0006] A plurality of third V-shaped grooves are formed on the side surface of the light emitting diode, and each of the third V-shaped grooves connects a corresponding first groove and a corresponding second groove.

[0007] Then, a first laser treatment is performed on the side surface of the light emitting diode to form a plurality of randomly arranged first nano-pits on the side surface of the light emitting diode.

[0008] A first inorganic passivation layer, a second organic passivation layer and a third inorganic passivation layer are formed on the upper surface, the lower surface and the side surface of the light-emitting diode, and the first inorganic passivation layer, the second organic passivation layer and the third inorganic passivation layer fill the first annular groove, the first groove, the second annular groove, the second groove and the third V-shaped groove.

[0009] Then, a second laser treatment is performed on the side surface of the light emitting diode to form a plurality of randomly arranged second nano-pits on the side surface of the light emitting diode.

[0010] As a preferred embodiment, the epitaxial functional layer includes a first semiconductor layer, a quantum well light-emitting layer, and a second semiconductor layer that are stacked.

[0011] As a preferred embodiment, the first annular groove is located in the transparent conductive layer, and the ratio of the depth of the first annular groove to the thickness of the transparent conductive layer is 0.3-0.5.

[0012] As a preferred embodiment, the second annular groove passes through the back metal layer and is embedded in the substrate, and the ratio of the depth of the second annular groove to the thickness of the substrate is 0.1-0.3.

[0013] As a preferred embodiment, the material of the first inorganic passivation layer and the third inorganic passivation layer is one of aluminum oxide, zirconium oxide, silicon nitride, and silicon oxynitride, and the material of the second organic passivation layer is one of polyvinyl alcohol, polyetherimide, polystyrene, and polymethyl methacrylate.

[0014] As a preferred embodiment, the first inorganic passivation layer and the third inorganic passivation layer are formed by atomic layer deposition, magnetron sputtering or PECVD, and the second organic passivation layer is formed by a wet coating process.

[0015] As a preferred embodiment, further, a fourth passivation layer is formed on the upper surface and the lower surface of the light emitting diode, and the fourth passivation layer fills the first annular groove and the second annular groove.

[0016] As a preferred embodiment, the first annular groove, the first groove, the second annular groove, the second groove and the third V-shaped groove are formed by a wet etching process or a dry etching process. The present invention further provides a light emitting diode, which is formed by using the above-mentioned side repair method of a light emitting diode.

[0017] Compared with the prior art, the side repair method of a light-emitting diode and the light-emitting diode of the present invention have the following beneficial effects: In the side repair method of the light-emitting diode of the present invention, a first annular groove and a plurality of first grooves are formed on the upper surface of the light-emitting diode, wherein the plurality of first grooves are connected to the first annular groove; a second annular groove and a plurality of second grooves are formed on the lower surface of the light-emitting diode, wherein the plurality of second grooves are connected to the second annular groove; and a plurality of third V-shaped grooves are formed on the side of the light-emitting diode, wherein each third V-shaped groove is connected to a corresponding first groove and a second groove. Then, in the subsequent process of forming the first inorganic passivation layer, the second organic passivation layer, and the third inorganic passivation layer, a portion of the first inorganic passivation layer, the second organic passivation layer, and the third inorganic passivation layer is embedded in the above-mentioned grooves, thereby effectively preventing the peeling of the passivation layers. Then, the side of the light-emitting diode is subjected to a first laser treatment to form a plurality of randomly arranged first nano-pits on the side of the light-emitting diode, and the side of the light-emitting diode is subjected to a second laser treatment to form a plurality of randomly arranged second nano-pits on the side of the light-emitting diode. The presence of the above-mentioned nano-pits effectively improves the light extraction efficiency of the light-emitting diode. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 A schematic structural diagram of the light emitting diode of this application; Figure 2 A top view of a light emitting diode in which a first annular groove and a plurality of first grooves are formed in the present application; Figure 3 A bottom view of a light emitting diode having a second annular groove and a plurality of second grooves formed therein in the present application; Figure 4 A side view of a light emitting diode having a plurality of third V-shaped grooves formed therein in the present application; Figure 5 Schematic cross-sectional view of a light-emitting diode in which a first inorganic passivation layer, a second organic passivation layer, and a third inorganic passivation layer are formed in the present application; Figure 6 It is a cross-sectional schematic diagram of a light-emitting diode with a fourth passivation layer formed in this application.

[0020] Description of reference numerals: 100, light-emitting diode; 101, back metal layer; 102, substrate; 103, epitaxial functional layer; 104, transparent conductive layer; 105, surface electrode; 201, first annular groove; 202, first groove; 301, second annular groove; 302, second groove; 401, third V-shaped groove; 500, passivation layer; 600, fourth passivation layer. DETAILED DESCRIPTION

[0021] The following will describe in detail the implementation methods of the present application in conjunction with the accompanying drawings and examples, so that the implementation process of how the present application applies technical means to solve technical problems and achieve corresponding technical effects can be fully understood and implemented accordingly. The embodiments of the present application and the various features therein can be combined with each other without conflict, and the technical solutions formed are all within the scope of protection of this application. In the drawings, the sizes and relative sizes of layers and regions may be exaggerated for clarity. The same reference numerals throughout represent the same elements.

[0022] It should be understood that although the terms "first," "second," "third," etc. may be used to describe various elements, components, regions, layers, and / or portions, these elements, components, regions, layers, and / or portions should not be limited by these terms. These terms are merely used to distinguish one element, component, region, layer, or portion from another element, component, region, layer, or portion. Thus, a first element, component, region, layer, or portion discussed below may be referred to as a second element, component, region, layer, or portion without departing from the teachings of this application.

[0023] It will be understood that spatially relative terms, such as "above," "above," "below," "beneath," etc., may be used herein for convenience to describe the relationship of one element or feature to other elements or features illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use and operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, then elements or features described as "below other elements" would then be oriented "above" the other elements or features. Thus, the exemplary terms "below" and "beneath" can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatial descriptors used herein interpreted accordingly.

[0024] The purpose of the terms used herein is only to describe specific embodiments and is not intended to limit the present application. When used herein, the singular forms "a", "an", and "the" are intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "comprising" and / or "including", when used in this specification, determine the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0025] Embodiments of the present application are described herein with reference to cross-sectional illustrations that are schematic illustrations of idealized embodiments (and intermediate structures) of the present application. As such, variations from the illustrated shapes due to, for example, manufacturing techniques and / or tolerances are contemplated. Thus, embodiments of the present application should not be limited to the specific shapes of regions illustrated herein, but rather include deviations in shapes due to, for example, manufacturing techniques.

[0026] In order to fully understand the present application, detailed structures and steps will be provided in the following description to illustrate the technical solutions proposed by the present application. The preferred embodiments of the present application are described in detail below. However, in addition to these detailed descriptions, the present application may also have other implementation methods.

[0027] An embodiment of the present application provides a method for repairing a side surface of a light-emitting diode, the method comprising the following steps: like Figure 1 As shown, a light emitting diode 100 is provided. The light emitting diode includes a back metal layer 101 , a substrate 102 , an epitaxial functional layer 103 , a transparent conductive layer 104 and a surface electrode 105 .

[0028] In a specific embodiment, the epitaxial functional layer 103 includes a first semiconductor layer, a quantum well light-emitting layer, and a second semiconductor layer (not shown) that are stacked.

[0029] In a specific embodiment, the substrate 102 is a gallium nitride substrate, the first semiconductor layer is an N-type nitride layer or a P-type nitride layer, the quantum well light-emitting layer is a gallium nitride-based multi-quantum well light-emitting layer, and the second semiconductor layer is a P-type nitride layer or an N-type nitride layer; when the first semiconductor layer is an N-type nitride layer, the second semiconductor layer is a P-type nitride layer, and when the first semiconductor layer is a P-type nitride layer, the second semiconductor layer is an N-type nitride layer, preferably, the N-type nitride layer is an N-type gallium nitride layer, and the P-type nitride is a P-type gallium nitride layer.

[0030] In a specific embodiment, the transparent conductive layer 104 is ITO, IZO or FTO, and the material of the back metal layer 101 and the surface electrode 105 is one or more of copper, aluminum, titanium, silver, gold, and palladium, and the back metal layer 101 and the surface electrode 105 are formed by thermal evaporation or magnetron sputtering process.

[0031] like Figure 2 As shown, a first annular groove 201 and a plurality of first grooves 202 are formed on the upper surface of the light emitting diode 100 , and the plurality of first grooves 202 are connected to the first annular groove 201 .

[0032] In a specific embodiment, the first annular groove 201 is located in the transparent conductive layer 104 , and the ratio of the depth of the first annular groove 201 to the thickness of the transparent conductive layer 104 is 0.3-0.5.

[0033] The first annular groove 201 and the first groove 202 are formed by a wet etching process or a dry etching process.

[0034] In a specific embodiment, photoresist can be spin-coated on the upper surface of the light-emitting diode 100, and then an exposure and development process is performed to form a photoresist mask. The transparent conductive layer 104 is then wet-etched using the photoresist mask, and the first annular groove 201 and the multiple first grooves 202 are simultaneously formed in the same wet etching process, so that the depths of the first annular groove 201 and the first grooves 202 are the same. Specifically, the ratio of the depth of the first annular groove 201 to the thickness of the transparent conductive layer 104 is 0.35, 0.4 or 0.45.

[0035] In another embodiment, the first annular groove 201 and the multiple first grooves 202 can be formed by a laser etching process. More specifically, a laser mask is used to first perform laser processing on the area where the first annular groove 201 is set in the transparent conductive layer 104 for a certain time, and then another laser mask is replaced to expose the area of ​​the transparent conductive layer 104 where the first annular groove 201 is formed and the area where the multiple first grooves 202 are formed, and then laser etching is performed again for a certain time to form the first annular groove 201 and the multiple first grooves 202, so that the depth of the first annular groove 202 is smaller than the depth of the first annular groove 201, and the ratio of the depth of the first annular groove 201 to the thickness of the transparent conductive layer 104 is 0.35, 0.4 or 0.45.

[0036] like Figure 3As shown, a second annular groove 301 and a plurality of second grooves 302 are formed on the lower surface of the light emitting diode 100 , and the plurality of second grooves 302 are connected to the second annular groove 301 .

[0037] In a specific embodiment, the second annular groove 301 passes through the back metal layer 101 and is embedded in the substrate 102 , and a ratio of a depth of the second annular groove 301 to a thickness of the substrate 102 is 0.1-0.3.

[0038] The second annular groove 301 and the second groove 302 are formed by a wet etching process or a dry etching process.

[0039] In a specific embodiment, photoresist can be spin-coated on the lower surface of the light-emitting diode 100, and then an exposure and development process is performed to form a photoresist mask, and then the back metal layer 101 and the substrate 102 are wet-etched using the photoresist mask. In the same wet etching process, the second annular groove 301 and the plurality of second grooves 302 are simultaneously formed, so that the depths of the second annular groove 301 and the second grooves 302 are the same. Specifically, the ratio of the depth of the second annular groove 301 to the thickness of the substrate 102 is 0.15, 0.2 or 0.25.

[0040] In another embodiment, the second annular groove 301 and the plurality of second grooves 302 can be formed by a laser etching process. More specifically, using a laser mask, the area where the second annular groove 301 is set in the back metal layer 101 and the substrate 102 is first laser treated for a certain time, and then another laser mask is replaced to expose the area where the second annular groove 301 is formed and the area where the plurality of second grooves 302 are formed, and then laser etching is performed for a certain time to form the second annular groove 301 and the plurality of second grooves 302, so that the depth of the second groove 302 is less than the depth of the second annular groove 301, and the ratio of the depth of the second annular groove 301 to the thickness of the substrate 102 is 0.15, 0.2 or 0.25.

[0041] like Figure 4 As shown, a plurality of third V-shaped grooves 401 are formed on the side of the light emitting diode 100 , and each of the third V-shaped grooves 401 connects a corresponding first groove 202 and a corresponding second groove 302 .

[0042] In a specific embodiment, the third V-shaped groove 401 is formed by a wet etching process or a dry etching process.

[0043] In a specific embodiment, the four sides of the light-emitting diode 100 can be wet-etched using a photoresist mask or formed by a laser etching process to form a plurality of third V-shaped grooves 401, so that each of the third V-shaped grooves 401 connects a corresponding first groove 202 and a second groove 302.

[0044] Then, a first laser treatment is performed on the side surface of the light emitting diode to form a plurality of randomly arranged first nano-pits (not shown) on the side surface of the light emitting diode.

[0045] In a specific embodiment, the four sides of the light-emitting diode are subjected to a first laser treatment, the wavelength range of the laser for the first laser treatment is between 515-532 nm, the energy density range of the laser is between 25-40 J / cm²‌, and the spot diameter is 1-3 μm. By adjusting the laser treatment time on the four sides of the light-emitting diode and the laser energy density, the depth of the first nano-pit is 100-500 nanometers. More specifically, the laser energy density can be adjusted to 25-30 J / cm²‌, 30-35 J / cm²‌, or 35-40 J / cm²‌, and the spot diameter is adjusted to 1 micron, 2 microns or 3 microns, thereby making the depth of the first nano-pit 100-200 nanometers, 200-300 nanometers, 300-400 nanometers or 400-500 nanometers.

[0046] like Figure 5 As shown, a passivation layer 500 is formed on the upper surface, lower surface and side surface of the light-emitting diode 100, and the passivation layer 500 includes a first inorganic passivation layer, a second organic passivation layer and a third inorganic passivation layer formed in sequence, and the first inorganic passivation layer, the second organic passivation layer and the third inorganic passivation layer fill the first annular groove, the first groove, the second annular groove, the second groove and the third V-shaped groove.

[0047] In a specific embodiment, the material of the first inorganic passivation layer and the third inorganic passivation layer is one of aluminum oxide, zirconium oxide, silicon nitride, and silicon oxynitride, and the material of the second organic passivation layer is one of polyvinyl alcohol, polyetherimide, polystyrene, and polymethyl methacrylate.

[0048] In a specific embodiment, the first inorganic passivation layer and the third inorganic passivation layer are formed by atomic layer deposition, magnetron sputtering or PECVD, and the second organic passivation layer is formed by a wet coating process.

[0049] In a specific embodiment, a zirconium oxide layer is deposited on the upper surface, lower surface and side surface of the light-emitting diode 100 by a PECVD process as a first inorganic passivation layer, and the thickness of the first inorganic passivation layer is 30-80 nanometers. Then, a polyvinyl alcohol solution or a polyetherimide solution is sprayed by a spraying process, and then heat treated to form a second organic passivation layer, and the thickness of the second organic passivation layer is 2-8 nanometers. Then, silicon nitride is deposited as a third inorganic passivation layer by a PECVD process, and the thickness of the third inorganic passivation layer is 200-500 nanometers.

[0050] Then, a second laser treatment is performed on the side surface of the light emitting diode 100 to form a plurality of randomly arranged second nano-pits (not shown) on the side surface of the light emitting diode.

[0051] In a specific embodiment, the four sides of the light-emitting diode are subjected to a second laser treatment, the wavelength range of the laser for the second laser treatment is between 515-532 nm, the energy density range of the laser is 5-15 J / cm²‌, and the spot diameter is 1-3 μm. By adjusting the laser treatment time on the four sides of the light-emitting diode and the laser energy density, the depth of the first nano-pit is 50-150 nanometers. More specifically, the laser energy density can be adjusted to 5-10 J / cm²‌ or 10-15 J / cm²‌, and the spot diameter is adjusted to 1 micron, 2 microns or 3 microns, thereby making the depth of the first nano-pit 50-100 nanometers or 100-150 nanometers.

[0052] like Figure 6 As shown, a fourth passivation layer 600 is formed on the upper surface and the lower surface of the light emitting diode 100 , and the fourth passivation layer 600 fills the first annular groove 201 and the second annular groove 301 .

[0053] In a specific embodiment, the fourth passivation layer 600 may be made of an organic resin, specifically epoxy, and is formed by a slit coating process.

[0054] In the subsequent process, a portion of the passivation layer 500 and a portion of the fourth passivation layer 600 are removed through a hole opening process to expose the back metal layer 101 and the surface electrode 105 to facilitate electrical connection in the subsequent packaging process (not shown).

[0055] like Figure 6 As shown, the present invention further provides a light emitting diode, which is a light emitting diode formed by using the above-mentioned side repair method of the light emitting diode.

[0056] The above are only specific embodiments of the present application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A method for repairing the side of a light-emitting diode, characterized in that: The side repair method of the light emitting diode comprises the following steps: A light-emitting diode is provided, comprising a back metal layer, a substrate, an epitaxial functional layer, a transparent conductive layer, and a surface electrode; A first annular groove and a plurality of first grooves are formed on the upper surface of the light emitting diode, wherein the plurality of first grooves are connected to the first annular groove; A second annular groove and a plurality of second grooves are formed on the lower surface of the light emitting diode, wherein the plurality of second grooves are connected to the second annular groove; A plurality of third V-shaped grooves are formed on the side of the light emitting diode, each of the third V-shaped grooves connecting a corresponding first groove and a corresponding second groove; Then, a first laser treatment is performed on the side surface of the light-emitting diode to form a plurality of randomly arranged first nano-pits on the side surface of the light-emitting diode; forming a first inorganic passivation layer, a second organic passivation layer, and a third inorganic passivation layer on the upper surface, the lower surface, and the side surface of the light-emitting diode, wherein the first inorganic passivation layer, the second organic passivation layer, and the third inorganic passivation layer fill the first annular groove, the first groove, the second annular groove, the second groove, and the third V-shaped groove; Then, a second laser treatment is performed on the side surface of the light emitting diode to form a plurality of randomly arranged second nano-pits on the side surface of the light emitting diode.

2. The method for repairing the side of a light emitting diode according to claim 1, wherein: The epitaxial functional layer includes a first semiconductor layer, a quantum well light-emitting layer and a second semiconductor layer which are stacked.

3. The method for repairing the side of a light emitting diode according to claim 1, wherein: The first annular groove is located in the transparent conductive layer, and the ratio of the depth of the first annular groove to the thickness of the transparent conductive layer is 0.3-0.

5.

4. The method for repairing the side surface of a light emitting diode according to claim 1, wherein: The second annular groove passes through the back metal layer and is embedded in the substrate, and the ratio of the depth of the second annular groove to the thickness of the substrate is 0.1-0.

3.

5. The method for repairing the side of a light emitting diode according to claim 1, wherein: The material of the first inorganic passivation layer and the third inorganic passivation layer is one of aluminum oxide, zirconium oxide, silicon nitride, and silicon oxynitride. The material of the second organic passivation layer is one of polyvinyl alcohol, polyetherimide, polystyrene, and polymethyl methacrylate.

6. The method for repairing the side surface of a light emitting diode according to claim 1, wherein: The first inorganic passivation layer and the third inorganic passivation layer are formed by atomic layer deposition, magnetron sputtering or PECVD, and the second organic passivation layer is formed by a wet coating process.

7. The method for repairing the side surface of a light emitting diode according to claim 1, wherein: Furthermore, a fourth passivation layer is formed on the upper surface and the lower surface of the light emitting diode, and the fourth passivation layer fills the first annular groove and the second annular groove.

8. The method for repairing the side surface of a light emitting diode according to claim 1, wherein: The first annular groove, the first groove, the second annular groove, the second groove and the third V-shaped groove are formed by a wet etching process or a dry etching process.

9. A light emitting diode, characterized in that: The light-emitting diode is formed by using the side repair method of a light-emitting diode according to any one of claims 1 to 8.

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