A method for repairing a side surface of a light emitting diode and a light emitting diode

Abstract

The application discloses a side repairing method of a light emitting diode and the light emitting diode, and the side repairing method comprises the following steps: forming a first annular groove and a plurality of first grooves on the upper surface of the light emitting diode, the plurality of first grooves being connected with the first annular groove; forming a second annular groove and a plurality of second grooves on the lower surface of the light emitting diode, the plurality of second grooves being connected with the second annular groove; forming a plurality of third V-shaped grooves on the side surface of the light emitting diode, each third V-shaped groove being connected with a corresponding first groove and a second groove; and then in the subsequent process of forming a first inorganic passivation layer, a second organic passivation layer and a third inorganic passivation layer, embedding part of the first inorganic passivation layer, the second organic passivation layer and the third inorganic passivation layer into the grooves, so that the peeling of the passivation layers can be effectively avoided.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor light-emitting, in particular to a side repairing method of a light-emitting diode and a light-emitting diode. BACKGROUND

[0002] The core of a light-emitting diode is a PN junction, which is formed by combining a P-type semiconductor and an N-type semiconductor. There are a large number of positive holes in the P-type semiconductor, and a large number of negative electrons in the N-type semiconductor. When a forward voltage is applied to the PN junction, the holes in the P region will diffuse to the N region, and the electrons in the N region will diffuse to the P region, and recombination will occur near the PN junction. When the electrons jump from a high energy level to a low energy level, they will release energy in the form of photons, thereby producing a light-emitting phenomenon. The color of the light depends on the energy gap width of the semiconductor material. Different energy gap materials will emit light of different wavelengths, thereby presenting different colors. In the existing light-emitting diode preparation process, the light-emitting diode chip is usually formed by a cutting process. However, the side wall of the light-emitting diode chip is easily damaged during the cutting process. How to improve the stability of the side wall of the light-emitting diode chip has attracted widespread attention. SUMMARY

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

[0004] To achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows:

[0005] The embodiment of the present application provides a side repairing method of a light-emitting diode, which comprises the following steps:

[0006] A light-emitting diode is provided, which comprises a back metal layer, a substrate, an epitaxial functional layer, a transparent conductive layer and a surface electrode.

[0007] 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 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, and the plurality of second grooves are connected to the second annular groove.

[0008] A plurality of third V-shaped grooves are formed on the side surface of the light-emitting diode, and each third V-shaped groove is connected to a corresponding first groove and a second groove.

[0009] 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.

[0010] A first inorganic passivation layer, a second organic passivation layer and a third inorganic passivation layer are formed on the upper surface, lower surface and 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.

[0011] 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.

[0012] As a preferred embodiment, the epitaxial functional layer comprises a first semiconductor layer, a quantum well light emitting layer and a second semiconductor layer arranged in a stack.

[0013] 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.

[0014] As a preferred embodiment, the second annular groove penetrates the back metal layer and is embedded into the substrate, and the ratio of the depth of the second annular groove to the thickness of the substrate is 0.1-0.3.

[0015] 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.

[0016] 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.

[0017] 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.

[0018] 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.

[0019] The application further provides a light emitting diode formed by the side surface repair method of the light emitting diode.

[0020] Compared with the prior art, the side surface repair method of the light emitting diode and the light emitting diode have the following beneficial effects:

[0021] In the method for repairing the side of the light emitting diode, a first annular groove and a plurality of first grooves are formed on the upper surface of the light emitting diode, 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, 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 is connected to a corresponding first groove and a second groove, and then in the subsequent process of forming a first inorganic passivation layer, a second organic passivation layer and a third inorganic passivation layer, part of the first inorganic passivation layer, the second organic passivation layer and the third inorganic passivation layer are embedded in the grooves, so that the peeling of the passivation layers can be effectively avoided. Then, a first laser treatment is performed on the side of the light emitting diode to form a plurality of randomly arranged first nano pits on the side of the light emitting diode, and a second laser treatment is performed on the side of the light emitting diode to form a plurality of randomly arranged second nano pits on the side of the light emitting diode, and the existence of the nano pits effectively improves the light emitting efficiency of the light emitting diode. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0023] Figure 1 The structure of the light emitting diode of the present application is shown in the schematic diagram.

[0024] Figure 2 The top view of the light emitting diode in which a first annular groove and a plurality of first grooves are formed in the present application.

[0025] Figure 3 The bottom view of the light emitting diode in which a second annular groove and a plurality of second grooves are formed in the present application.

[0026] Figure 4 The side view of the light emitting diode in which a plurality of third V-shaped grooves are formed in the present application.

[0027] Figure 5 The cross-sectional view of the 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.

[0028] Figure 6 The cross-sectional view of the light emitting diode in which a fourth passivation layer is formed in the present application.

[0029] BRIEF DESCRIPTION OF DRAWINGS:

[0030] 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

[0031] The embodiments of the present application will be described in detail below with reference to the drawings and examples, so that how the technical means of the present application is applied to solve the technical problems and achieve the corresponding technical effects can be fully understood and implemented. The embodiments of the present application and each feature in the examples can be combined with each other without conflict, and the formed technical solutions are all within the protection scope of the present application. In the drawings, the sizes and relative sizes of layers and regions may be exaggerated for clarity. The same reference signs represent the same elements throughout.

[0032] It should be understood that although the terms "first", "second", "third", etc. are used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, the first element, component, region, layer or part discussed below can be represented as the second element, component, region, layer or part without departing from the teachings of the present application.

[0033] It should be understood that spatial relationship terms, such as "above", "upper", "below", "lower", etc., can be used herein for ease of description to describe the relationship between one element or feature and another element or feature as shown in the drawings. It should be understood that in addition to the orientation shown in the drawings, the spatial relationship terms are intended to include different orientations of the device in use and operation. For example, if the device in the drawings is turned over, then the element or feature described as "below" the other element or feature will be oriented "above" the other element or feature. Therefore, the exemplary terms "below" and "under" can include both the upward and downward orientations. The device can be additionally oriented (rotated 90 degrees or other orientations) and the spatial descriptions used herein are interpreted accordingly.

[0034] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. When used herein, the singular forms “a,” “an,” and “the” are also 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, identify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0035] Embodiments of this application are described herein with reference to cross-sectional views illustrating ideal embodiments (and intermediate structures). Thus, variations in the shape shown can be anticipated due to, for example, fabrication techniques and / or tolerances. Therefore, embodiments of this application should not be limited to the specific shape of the region shown herein, but should include shape deviations due to, for example, fabrication processes.

[0036] To fully understand this application, detailed structures and steps will be presented in the following description to illustrate the technical solutions proposed in this application. Preferred embodiments of this application are described in detail below; however, in addition to these detailed descriptions, this application may have other implementation methods.

[0037] Embodiments of this application provide a method for repairing the side surface of a light-emitting diode (LED), the method comprising the following steps:

[0038] like Figure 1 As shown, a light-emitting diode 100 is provided, the light-emitting diode including a back metal layer 101, a substrate 102, an epitaxial functional layer 103, a transparent conductive layer 104, and a surface electrode 105.

[0039] 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) stacked together.

[0040] 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 multiple 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 and 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 layer is a P-type gallium nitride layer.

[0041] In specific embodiments, the transparent conductive layer 104 is ITO, IZO or FTO, the back metal layer 101 and the surface electrode 105 are made of one or more of copper, aluminum, titanium, silver, gold, palladium, and the back metal layer 101 and the surface electrode 105 are formed by thermal evaporation or magnetron sputtering process.

[0042] As shown in FIG. 1, 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. Figure 2

[0043] In specific embodiments, 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.

[0044] The first annular groove 201 and the first grooves 202 are formed by a wet etching process or a dry etching process.

[0045] In specific embodiments, the first annular groove 201 and the plurality of first grooves 202 can be formed by spin-coating photoresist on the upper surface of the light emitting diode 100, then forming a photoresist mask by exposure and development process, and then wet etching the transparent conductive layer 104 using the photoresist mask, and the first annular groove 201 and the plurality of first grooves 202 are formed in the same wet etching process, so that the depth of the first annular groove 201 and the first grooves 202 is the same, and 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.

[0046] In another embodiment, the first annular groove 201 and the plurality of first grooves 202 can be formed by a laser etching process, and more specifically, a laser mask is used to perform laser treatment on the area of the transparent conductive layer 104 where the first annular groove 201 is located for a certain period of time, then another laser mask is replaced to expose the area of the transparent conductive layer 104 where the first annular groove 201 and the plurality of first grooves 202 are formed, and then laser etching treatment is performed for a certain period of time to form the first annular groove 201 and the plurality of first grooves 202, so that the depth of the first grooves 202 is less 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.

[0047] As shown in FIG. 1, 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. Figure 3 ​As 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.

[0048] In a specific embodiment, the second annular groove 301 penetrates the back metal layer 101 and is embedded in the substrate 102, and the ratio of the depth of the second annular groove 301 to the thickness of the substrate 102 is 0.1-0.3.

[0049] The second annular groove 301 and the second groove 302 are formed by a wet etching process or a dry etching process.

[0050] In a specific embodiment, photoresist can be spin-coated onto the lower surface of the light-emitting diode 100, and then a photoresist mask can be formed by exposure and development. The photoresist mask is then used to perform wet etching on the back metal layer 101 and the substrate 102. In the same wet etching process, a second annular groove 301 and multiple second grooves 302 are formed simultaneously, 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.

[0051] In another embodiment, the second annular groove 301 and multiple second grooves 302 can be formed by laser etching. More specifically, using a laser mask, the area where the second annular groove 301 is formed in the back metal layer 101 and the substrate 102 is first laser-processed for a certain period of time. Then, another laser mask is used to expose the area where the second annular groove 301 is formed and the area where multiple second grooves 302 are formed. Then, laser etching is performed for a certain period of time to form the second annular groove 301 and multiple second grooves 302. This results in the depth of the second groove 302 being 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 being 0.15, 0.2, or 0.25.

[0052] 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 third V-shaped groove 401 is connected to a corresponding first groove 202 and a second groove 302.

[0053] In a specific embodiment, the third V-shaped groove 401 is formed by a wet etching process or a dry etching process.

[0054] 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, such that each third V-shaped groove 401 is connected to a corresponding first groove 202 and a second groove 302.

[0055] Next, the side surface of the light-emitting diode is subjected to a first laser treatment to form a plurality of randomly arranged first nano-pits (not shown) on the side surface of the light-emitting diode.

[0056] 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 used in the first laser treatment is between 515-532 nm, the energy density range is 25-40 J / cm², and the spot diameter is 1-3 μm. By adjusting the processing time and energy density of the laser on the four sides of the light-emitting diode, the depth of the first nano-pit is made to be 100-500 nanometers. More specifically, the energy density range of the laser can be adjusted to be 25-30 J / cm², 30-35 J / cm², or 35-40 J / cm², and the spot diameter can be adjusted to be 1 μm, 2 μm, or 3 μm, thereby making the depth of the first nano-pit 100-200 nanometers, 200-300 nanometers, 300-400 nanometers, or 400-500 nanometers.

[0057] 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. The passivation layer 500 includes a first inorganic passivation layer, a second organic passivation layer and a third inorganic passivation layer formed sequentially. 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.

[0058] In a specific embodiment, the materials of the first inorganic passivation layer and the third inorganic passivation layer are one of alumina, 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.

[0059] 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.

[0060] 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 as a first inorganic passivation layer by a PECVD process, the thickness of the first inorganic passivation layer is 30-80 nm, then a polyvinyl alcohol solution or a polyetherimide solution is sprayed by a spraying process, and then a heat treatment is performed to form a second organic passivation layer, the thickness of the second organic passivation layer is 2-8 nm, and then a silicon nitride is deposited as a third inorganic passivation layer by a PECVD process, the thickness of the third inorganic passivation layer is 200-500 nm.

[0061] 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.

[0062] In a specific embodiment, the four side surfaces of the light emitting diode are subjected to a second laser treatment, the wavelength of the laser of the second laser treatment ranges from 515-532 nm, the energy density of the laser ranges from 5-15 J / cm², and the spot diameter is 1-3 μm. By adjusting the processing time of the laser on the four side surfaces of the light emitting diode and the energy density of the laser, the depth of the first nano pits is 50-150 nm. More specifically, the energy density of the laser can be adjusted to range from 5-10 J / cm² or 10-15 J / cm², and the spot diameter can be adjusted to be 1 μm, 2 μm or 3 μm, so that the depth of the first nano pits is 50-100 nm or 100-150 nm.

[0063] As shown in Figure 6 A fourth passivation layer 600 is formed on the upper surface and 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.

[0064] In a specific embodiment, the fourth passivation layer 600 can be an organic resin, specifically an epoxy, and the fourth passivation layer 600 is formed by a slot coating process.

[0065] In a subsequent process, part of the passivation layer 500 and part of the fourth passivation layer 600 are removed by a hole opening process to expose the back metal layer 101 and the surface electrode 105, so as to facilitate the electrical connection in the subsequent packaging process (not shown).

[0066] As shown in Figure 6 The present application also provides a light emitting diode formed by the side surface repair method of the light emitting diode.

[0067] The above merely provides the specific implementation of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can easily think of the changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for repairing the side surface of a light-emitting diode, characterized in that: The side repair method for the light-emitting diode includes the following steps: A light-emitting diode is provided, the light-emitting diode including 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, and 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, and the plurality of second grooves are connected to the second annular groove; Multiple third V-shaped grooves are formed on the side of the light-emitting diode, and each third V-shaped groove is connected to a corresponding first groove and a second groove; Next, the side surface of the light-emitting diode is subjected to a first laser treatment to form multiple randomly arranged first nano-pits on the side surface of the light-emitting diode. A first inorganic passivation layer, a second organic passivation layer, and a third inorganic passivation layer are formed on the upper surface, lower surface, and side surface of the light-emitting diode. 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. Next, a second laser treatment is performed on the side surface of the light-emitting diode to form multiple randomly arranged second nano-pits on the side surface of the light-emitting diode.

2. The side repair method for a light-emitting diode according to claim 1, characterized in that: The epitaxial functional layer includes a first semiconductor layer, a quantum well light-emitting layer, and a second semiconductor layer stacked together.

3. The side repair method for a light-emitting diode according to claim 1, characterized in that: 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 side repair method for a light-emitting diode according to claim 1, characterized in that: The second annular groove penetrates 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 side repair method for a light-emitting diode according to claim 1, characterized in that: The first and third inorganic passivation layers are made of one of alumina, zirconium oxide, silicon nitride, and silicon oxynitride, and the second organic passivation layer is made of one of polyvinyl alcohol, polyetherimide, polystyrene, and polymethyl methacrylate.

6. The side repair method for a light-emitting diode according to claim 1, characterized in that: The first and third inorganic passivation layers 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 side repair method for a light-emitting diode according to claim 1, characterized in that: Furthermore, a fourth passivation layer is formed on the upper and lower surfaces of the light-emitting diode, and the fourth passivation layer fills the first annular groove and the second annular groove.

8. The side repair method for a light-emitting diode according to claim 1, characterized in that: The first annular groove, the first groove, the second annular groove, the second groove, and the third V-shaped groove are formed by wet etching or dry etching.

9. A light-emitting diode, characterized in that, The light-emitting diode is a light-emitting diode formed after being processed by the side repair method of any one of claims 1-8.

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