LED chip and etching method thereof

Abstract

The present invention discloses an LED chip and an etching method thereof, and relates to the field of LED lighting technology. The LED chip etching method comprises the following steps: S1, providing a chip substrate; S2, arranging a current blocking layer, a metal conductive layer, a current spreading layer, and a passivation layer on the substrate epitaxial layer in S1; S3, removing the etching glue from the initial etching product in S2; S4, performing photolithography processing on the positive photoresist and the negative photoresist, respectively. By performing n etchings to achieve deep etching of the LED chip, the etching work can be carried out regularly, thereby avoiding the phenomenon of disorder in the processing process and improving the processing efficiency of the etching; by performing etching multiple times, the interface of the processed LED chip is made smoother, and by cleaning with a plasma cleaning machine, the possibility of leakage of the LED chip can be avoided, further improving the yield rate of the LED chip and the yield rate of LED chip production.

Description

Technical Field

[0001] The present invention relates to the technical field of LED lighting, in particular to an LED chip and an etching method thereof. Background Art

[0002] The LED chip is a solid-state semiconductor device. The heart of the LED is a semiconductor wafer, attached to a bracket at one end. One end of the wafer is the cathode, and the other end is connected to the positive terminal of a power source, encapsulating the entire wafer in epoxy resin. Also known as the LED light-emitting chip, it is the core component of an LED lamp, specifically the PN junction. Its primary function is to convert electrical energy into light energy. The chip is primarily made of single-crystal silicon. The semiconductor wafer consists of two parts: a P-type semiconductor, where holes predominate, and an N-type semiconductor, where electrons predominate.

[0003] Etching is a crucial step in semiconductor manufacturing, microelectronic IC manufacturing, and micro-nano manufacturing. It is a key process in patterning, often associated with photolithography. Etching, in a narrower sense, is essentially photolithographic etching, where the photoresist is first exposed through photolithography, and then the desired portion is etched away through other methods. Etching selectively removes unwanted material from the surface of a silicon wafer using chemical or physical methods. Its fundamental goal is to accurately replicate the mask pattern on the coated silicon wafer. With the advancement of microfabrication processes, etching has broadly become a general term for the removal of material using solutions, reactive ions, or other mechanical methods.

[0004] In the existing technology, an etching manufacturing process can be used for processing in the actual LED chip process. If the board layer of the LED chip is excessively etched during the etching process, the processing efficiency will be low. In addition, since the etching steps are not obvious, the processing process will be disordered, affecting the yield of the LED chip. In view of this, we propose an LED chip and an etching method thereof. Summary of the Invention

[0005] (1) Technical problems solved

[0006] In view of the deficiencies of the prior art, the present invention provides an LED chip and an etching method thereof, which solve the problems mentioned in the above background technology.

[0007] (2) Technical solution

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions: A method for etching an LED chip, the method comprising the following steps:

[0009] S1. Providing a chip substrate and spraying an epitaxial layer on the substrate;

[0010] S2, set the current blocking layer, metal conductive layer, current spreading layer and passivation layer on the substrate epitaxial layer in S1, and deposit the SiO2 layer while protecting the non-corrosion area. CUT is made of yellow light, where the thickness of SiO2 is It is used to provide good protection for the non-corrosion area and perform a primary etching on the passivation layer to obtain a primary etching product;

[0011] S3, removing the etchant from the primary etching product in S2, and applying positive photoresist to the side of the epitaxial layer away from the substrate, exposing, developing, and erecting the positive photoresist, and applying negative photoresist to the side of the epitaxial layer close to the substrate, exposing, developing, and erecting the negative photoresist;

[0012] S4. Perform photolithography on the positive photoresist and the negative photoresist respectively, and expose the area to be etched of the transparent conductive layer, perform plasma cleaning on the area to be etched, and perform n etchings, where n starts from 1 and is an integer, and the etching is performed in order from the 1st etching to the nth etching, and the temperature of each etching is directly proportional to n, and the concentration of the etching solution in each etching is negatively proportional to n.

[0013] Optionally, the etching temperature is 42-82 degrees Celsius.

[0014] Optionally, the concentration of the etching solution is 1.2*10 -6 mlo / L-3.5*10 -6 mlo / L.

[0015] Optionally, the etching time of the first etching is 30-450s.

[0016] Optionally, during the n etching processes, the concentration of the etching solution used in the latter of any two adjacent etching processes is 0.65-0.75 times the concentration of the etching solution used in the previous etching process, and the etching time in any two adjacent etching processes during the n etching processes is the same.

[0017] Optionally, during the n etching processes, the etching temperature used in the latter of any two adjacent etchings is 1.0125-1.15 times the etching temperature used in the former etching.

[0018] Optionally, after the nth etching, the LED chip is placed under the BOE solution to remove the flooding film and is cleaned and blow-dried. The mask silicon of the aisle to be etched is wet-etched at room temperature, and then ICP dry etching is performed. High-pressure N2 is used for drying, and the cleaned LED chip is thoroughly cleaned and dried.

[0019] Optionally, the BOE solution is composed of a mixture of H2SO4 and H3PO4, and the volume ratio of H2SO4 to H3PO4 is 2:7.

[0020] Optionally, the plasma cleaning treatment is performed in a gas environment of one or more of oxygen, methane, and argon, and a plasma cleaning machine is used for the plasma cleaning treatment. The radio frequency power of the plasma cleaning machine is 45W-750W, and the plasma cleaning treatment time is 25-400S.

[0021] An LED chip is manufactured by adopting the above-mentioned LED chip etching method.

[0022] (3) Beneficial effects

[0023] The present invention provides an LED chip and an etching method thereof, which has the following beneficial effects:

[0024] (1) The LED chip and the etching method thereof can achieve deep etching of the LED chip by performing n etchings at the same time, and can perform the etching work regularly, thereby avoiding the phenomenon of disorder in the processing process, making it possible to improve the processing efficiency of etching and improve the yield rate of LED chip production.

[0025] (2) The LED chip and its etching method can make the interface of the processed LED chip smoother by etching multiple times, and can avoid the possibility of leakage of the LED chip by cleaning with a plasma cleaning machine, thereby further improving the yield rate of the LED chip.

[0026] (3) The LED chip and its etching method can effectively improve the light transmittance of the LED chip by performing multiple etchings and exposing, developing and vertical film operations on the positive photoresist and the negative photoresist respectively, thereby further improving the quality of the LED chip and being suitable for promotion and use. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the process structure of the present invention;

[0028] Figure 2 Schematic diagram of the structure of the LED chip of the present invention.

[0029] In the figure: 1, substrate; 2, epitaxial layer; 31, current blocking layer; 32, metal conductive layer; 33, current spreading layer; 34, passivation layer. DETAILED DESCRIPTION

[0030] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0031] Example 1:

[0032] See also Figure 1-Figure 2 The present invention provides a technical solution: a method for etching an LED chip, the method comprising the following steps:

[0033] S1, providing a chip substrate 1, and spraying an epitaxial layer 2 on the substrate 1;

[0034] S2, providing a current blocking layer 31, a metal conductive layer 32, a current spreading layer 33 and a passivation layer 34 on the epitaxial layer 2 of the substrate 1 in S1, and depositing a flooded SiO2 layer, and performing a primary etching on the passivation layer 34 to obtain a primary etching product;

[0035] S3, removing the etchant from the primary etching product in S2, and applying positive photoresist to the side of the epitaxial layer 2 away from the substrate 1, exposing, developing, and erecting the positive photoresist, and applying negative photoresist to the side of the epitaxial layer 2 close to the substrate 1, exposing, developing, and erecting the negative photoresist;

[0036] S4. Perform photolithography on the positive photoresist and the negative photoresist respectively, and expose the area to be etched of the transparent conductive layer, perform plasma cleaning on the area to be etched, and perform n etchings, where n starts from 1 and is an integer, and the etching is performed in order from the first etching to the nth etching, wherein the etching time of the first etching is 30-170s, and the temperature of each etching is in direct proportion to n, wherein the etching temperature is 42-82 degrees Celsius, and the concentration of the etching solution in each etching is inversely proportional to n, wherein the concentration of the etching solution is 1.2*10 -6 mlo / L-3.5*10 -6 mlo / L. By performing multiple etchings and exposing, developing, and vertical film operations on the positive photoresist and the negative photoresist respectively, the transmittance of the LED chip can be effectively improved, thereby further improving the quality of the LED chip, making it suitable for promotion and use.

[0037] In this embodiment, during the n-time etching process, the concentration of the etching solution used in the latter of any two adjacent etchings is 0.65-0.75 times the concentration of the etching solution used in the previous etching process, and the etching time in any two adjacent etching processes is the same. During the n-time etching process, the etching temperature used in the latter of any two adjacent etchings is 1.0125-1.15 times the etching temperature used in the previous etching process, and the material used for the etching solution is one or more of ammonium fluoride, oxalic acid, and hydrofluoric acid. By performing n-time etching to achieve deep etching of the LED chip, the etching work can be carried out regularly, thereby avoiding the phenomenon of disorder in the processing process, thereby improving the processing efficiency of the etching, and improving the yield rate of LED chip production.

[0038] After the nth etching, the LED chip is placed in a BOE solution for de-flooding, cleaning, and air drying. High-pressure N2 is used for drying. The BOE solution is composed of a mixture of H2SO4 and H3PO4, with a volume ratio of 2:7. This repeated etching process results in a smoother interface for the resulting LED chip. Cleaning in a plasma cleaner prevents electrical leakage, further improving the yield rate of the LED chip.

[0039] The plasma cleaning treatment is performed in a gas environment of one or more of oxygen, methane, and argon, and a plasma cleaning machine is used for the plasma cleaning treatment. The radio frequency power of the plasma cleaning machine is 45W-750W, and the plasma cleaning treatment time is 25-400S.

[0040] The present invention also provides a technical solution: an LED chip, which is manufactured using the above-mentioned LED chip etching method.

[0041] Example 2:

[0042] See also Figure 1-Figure 2 The present invention provides a technical solution: a method for etching an LED chip, the method comprising the following steps:

[0043] S1, providing a chip substrate 1, and spraying an epitaxial layer 2 on the substrate 1;

[0044] S2, providing a current blocking layer 31, a metal conductive layer 32, a current spreading layer 33 and a passivation layer 34 on the epitaxial layer 2 of the substrate 1 in S1, and depositing a flooded SiO2 layer, and performing a primary etching on the passivation layer 34 to obtain a primary etching product;

[0045] S3, removing the etchant from the primary etching product in S2, and applying positive photoresist to the side of the epitaxial layer 2 away from the substrate 1, exposing, developing, and erecting the positive photoresist, and applying negative photoresist to the side of the epitaxial layer 2 close to the substrate 1, exposing, developing, and erecting the negative photoresist;

[0046] S4. Perform photolithography on the positive photoresist and the negative photoresist respectively, and expose the area to be etched of the transparent conductive layer, perform plasma cleaning on the area to be etched, and perform n etchings, where n starts from 1 and is an integer, and the etching is performed in order from the first etching to the nth etching, wherein the etching time of the first etching is 170-310s, and the temperature of each etching is in direct proportion to n, wherein the etching temperature is 42-82 degrees Celsius, and the concentration of the etching solution in each etching is inversely proportional to n, wherein the concentration of the etching solution is 1.2*10 -6 mlo / L-3.5*10 -6 mlo / L.

[0047] In this embodiment, during the n-time etching process, the concentration of the etching solution used in the latter of any two adjacent etching processes is 0.65-0.75 times the concentration of the etching solution used in the previous etching process, and the etching time in any two adjacent etching processes is the same. During the n-time etching process, the etching temperature used in the latter of any two adjacent etching processes is 1.0125-1.15 times the etching temperature used in the previous etching process.

[0048] After the nth etching, the LED chip is placed in a BOE solution for de-flooding, cleaning, and air drying. High-pressure N2 is used for drying. The BOE solution is composed of a mixture of H2SO4 and H3PO4, with a volume ratio of 2:7.

[0049] The plasma cleaning treatment is performed in a gas environment of one or more of oxygen, methane, and argon, and a plasma cleaning machine is used for the plasma cleaning treatment. The radio frequency power of the plasma cleaning machine is 45W-750W, and the plasma cleaning treatment time is 25-400S.

[0050] The present invention also provides a technical solution: an LED chip, which is manufactured using the above-mentioned LED chip etching method.

[0051] Example 3:

[0052] See also Figure 1-Figure 2 The present invention provides a technical solution: a method for etching an LED chip, the method comprising the following steps:

[0053] S1, providing a chip substrate 1, and spraying an epitaxial layer 2 on the substrate 1;

[0054] S2, providing a current blocking layer 31, a metal conductive layer 32, a current spreading layer 33 and a passivation layer 34 on the epitaxial layer 2 of the substrate 1 in S1, and depositing a flooded SiO2 layer, and performing a primary etching on the passivation layer 34 to obtain a primary etching product;

[0055] S3, removing the etchant from the primary etching product in S2, and applying positive photoresist to the side of the epitaxial layer 2 away from the substrate 1, exposing, developing, and erecting the positive photoresist, and applying negative photoresist to the side of the epitaxial layer 2 close to the substrate 1, exposing, developing, and erecting the negative photoresist;

[0056] S4. Perform photolithography on the positive photoresist and the negative photoresist respectively, and expose the area to be etched of the transparent conductive layer, perform plasma cleaning on the area to be etched, and perform n etchings, where n starts from 1 and is an integer, and the etching is performed in order from the first etching to the nth etching, wherein the etching time of the first etching is 310-450s, and the temperature of each etching is in direct proportion to n, wherein the etching temperature is 42-82 degrees Celsius, and the concentration of the etching solution in each etching is inversely proportional to n, wherein the concentration of the etching solution is 1.2*10 -6 mlo / L-3.5*10 -6 mlo / L.

[0057] In this embodiment, during the n-time etching process, the concentration of the etching solution used in the latter of any two adjacent etching processes is 0.65-0.75 times the concentration of the etching solution used in the previous etching process, and the etching time in any two adjacent etching processes is the same. During the n-time etching process, the etching temperature used in the latter of any two adjacent etching processes is 1.0125-1.15 times the etching temperature used in the previous etching process.

[0058] After the nth etching, the LED chip is placed in a BOE solution for de-flooding, cleaning, and air drying. High-pressure N2 is used for drying. The BOE solution is composed of a mixture of H2SO4 and H3PO4, with a volume ratio of 2:7.

[0059] The plasma cleaning treatment is performed in a gas environment of one or more of oxygen, methane, and argon, and a plasma cleaning machine is used for the plasma cleaning treatment. The radio frequency power of the plasma cleaning machine is 45W-750W, and the plasma cleaning treatment time is 25-400S.

[0060] The present invention also provides a technical solution: an LED chip, which is manufactured using the above-mentioned LED chip etching method.

[0061] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for etching an LED chip, characterized in that: The etching method of the LED chip comprises the following steps: S1. Providing a chip substrate and spraying an epitaxial layer on the substrate; S2, providing a current blocking layer, a metal conductive layer, a current spreading layer and a passivation layer on the substrate epitaxial layer in S1, and depositing a flooded SiO2 layer, and performing a primary etching on the passivation layer to obtain a primary etching product; S3, removing the etchant from the primary etching product in S2, and applying positive photoresist to the side of the epitaxial layer away from the substrate, exposing, developing, and erecting the positive photoresist, and applying negative photoresist to the side of the epitaxial layer close to the substrate, exposing, developing, and erecting the negative photoresist; S4, performing photolithography on the positive photoresist and the negative photoresist respectively, exposing the to-be-etched area of ​​the transparent conductive layer, performing plasma cleaning on the to-be-etched area, and performing n etchings, where n starts from 1 and is an integer, and etching is performed in order from the first etching to the nth etching, and the temperature of each etching is in direct proportion to n, and the concentration of the etching solution in each etching is in inverse proportion to n; The etching temperature is 42-82 degrees Celsius; The concentration of the etching solution is 1.2*10 -6 mlo / L-3.5*10 -6 mlo / L; During the n etching processes, the concentration of the etching solution used in the latter of any two adjacent etching processes is 0.65-0.75 times the concentration of the etching solution used in the previous etching process, and the etching time in any two adjacent etching processes during the n etching processes is the same; During the n etching processes, the etching temperature used in the latter of any two adjacent etchings is 1.0125-1.15 times the etching temperature used in the former etching.

2. The method for etching an LED chip according to claim 1, wherein: The etching time of the first etching is 30-450s.

3. The method for etching an LED chip according to claim 1, wherein: After the nth etching, the LED chip is placed in a BOE solution for de-flooding, cleaning, and drying. High-pressure N2 is used for drying.

4. The method for etching an LED chip according to claim 3, wherein: The BOE solution is composed of a mixture of H2SO4 and H3PO4, and the volume ratio of H2SO4 to H3PO4 is 2:

7.

5. The method for etching an LED chip according to claim 1, wherein: The plasma cleaning treatment is performed in a gas environment of one or more of oxygen, methane, and argon, and is performed using a plasma cleaning machine. The radio frequency power of the plasma cleaning machine is 45W-750W, and the plasma cleaning treatment time is 25-400S.

6. An LED chip, characterized in that: The invention comprises an LED chip, wherein the LED chip is manufactured by the etching method of the LED chip according to any one of claims 1 to 5.

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