A method for manufacturing LED chip without etching and LED chip

Abstract

The invention relates to the technical field of LED production, and in particular to a method for producing an LED chip without etching and the LED chip. An innovative positioning means for an N-type semiconductor layer is proposed, and an N-electrode is produced on the side of the positioning position, thereby omitting the etching process steps in the conventional LED chip production process, simplifying the operation flow, and improving the work efficiency. The method comprises the following operation steps: S1, sequentially growing an epitaxial layer structure of an N-type semiconductor layer, a light-emitting layer, and a P-type semiconductor layer on the front side of a substrate; S2, producing a P-electrode above the P-type semiconductor layer; S3, determining that the thickness of the N-type semiconductor layer is X according to the epitaxial layer structure grown in step S1, the thickness from the bottom of the N-type semiconductor layer to the top of the P-type semiconductor layer is Y, and the total thickness of the light-emitting layer and the P-type semiconductor layer is Z, and the position of the N-electrode is set within a range of Y-Z to Y from the top of the P-type semiconductor layer; S4, producing the N-electrode on the side within the position range of the N-electrode determined in step S3.

Description

Technical Field

[0001] The invention relates to the technical field of LED production, and in particular to a method for producing an LED chip without etching and the LED chip. Background Art

[0002] Under existing technical conditions, conventional electrodes for both top-mounted and flip-chip LEDs are made by etching from the P-type semiconductor layer to the N-type semiconductor layer, and then plating metal to make the N-type electrode. Figure 1 To produce upright LEDs, the production of N-type electrodes requires that the epitaxial layer structure be etched from the P-type semiconductor layer to the N-type semiconductor layer, removing the edge of the stacked structure until the edge of the N-type semiconductor layer is exposed. On the one hand, the etching process is relatively complicated and time-consuming, and on the other hand, the epitaxial layer is etched and damaged, resulting in a large loss in the LED light emission. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a method for etching-free manufacturing of LED chips by optimizing the N-electrode manufacturing process, innovatively proposes a positioning means for the N-type semiconductor layer, and then manufactures the N-electrode on the side of the positioned position, omitting the etching process steps in the conventional LED chip manufacturing process, simplifying the operation process and improving work efficiency.

[0004] To achieve the above object, the present invention is implemented by adopting the following technical solutions:

[0005] In one aspect, the present invention provides a method for manufacturing an LED chip without etching, comprising the following steps:

[0006] S1, sequentially growing an epitaxial layer structure of an N-type semiconductor layer, a light-emitting layer, and a P-type semiconductor layer on the front side of the substrate;

[0007] S2, making a P electrode on the top of the P-type semiconductor layer;

[0008] S3, according to the epitaxial layer structure grown in step S1, the thickness of the N-type semiconductor layer is determined to be X, the thickness from the bottom of the N-type semiconductor layer to the top of the P-type semiconductor layer is Y, and the total thickness of the light-emitting layer and the P-type semiconductor layer is Z, then the position of the N electrode is set within a range of YZ to Y from the top of the P-type semiconductor layer;

[0009] S4. Fabricate an N-electrode on the side surface within the position range of the N-electrode determined in step S3.

[0010] In a possible technical solution, the material of the substrate is selected from any one of sapphire, silicon carbide, silicon, gallium nitride, ZnO, aluminum nitride and spinel.

[0011] In a possible technical solution, the epitaxial layer is stacked by metal organic chemical vapor deposition, molecular beam epitaxy or hydride vapor phase epitaxy.

[0012] In a possible technical solution, the P electrode and the N electrode are manufactured by sputtering or evaporation.

[0013] In a possible technical solution, the light-emitting layer is a single quantum well structure or a multi-quantum well structure, a quantum dot structure or a quantum wire structure.

[0014] In a possible technical solution, the N electrode is an electrode of Cr / Al / Ti or other structures.

[0015] In a possible technical solution, the side-forming N-electrode in step S4 includes the following steps:

[0016] S41, splitting the epitaxial layer structure of the manufactured P electrode into core particles;

[0017] S42, after fixing the core particle sideways, make an N electrode in the YZ~Y region.

[0018] In a possible technical solution, in step S41, the epitaxial layer structure is split into bar-shaped core particles.

[0019] In another aspect, the present invention provides an LED chip, which is manufactured by any of the above-mentioned methods for manufacturing an LED chip without etching.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention improves the cumbersome etching process required for LED production in the prior art, and innovatively proposes a positioning method for the N-type semiconductor layer. The positioning method physically measures the thickness according to the growth of the epitaxial layer structure. The measuring method is simple, and the positioning method is accurate and efficient. After completing the positioning step of the N-type semiconductor layer, an N electrode is made on the side of the positioning position. The overall process of the method for making an LED chip of the present invention can avoid the etching process steps in the conventional LED chip production process, prevent etching from damaging the epitaxial layer, simplify the operation process, improve work efficiency, reduce the loss of LED light emission, reduce the LED production cost, and is conducive to promotion and application in the industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the structure of LED chip in the prior art;

[0022] Figure 2 It is a structural schematic diagram of the method for manufacturing LED chips without etching of the present invention;

[0023] Figure 3 It is a schematic diagram of the epitaxial layer structure being split into bar-shaped core grain structures;

[0024] Figure numerals: 1-substrate; 2-N-type semiconductor layer; 3-light-emitting layer; 4-P-type semiconductor layer; 5-P electrode; 6-N electrode; 7-core particle. DETAILED DESCRIPTION

[0025] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0026] Example 1

[0027] like Figure 2 As shown, the method for manufacturing LED chips without etching in Embodiment 1 of the present invention comprises the following steps:

[0028] S1, sequentially growing an epitaxial layer structure of an N-type semiconductor layer 2, a light-emitting layer 3, and a P-type semiconductor layer 4 on the front surface of a substrate 1;

[0029] Among them, the material of the substrate 1 is selected from any one of sapphire, silicon carbide, silicon, gallium nitride, ZnO, aluminum nitride and spinel; the epitaxial layer is stacked by organic metal chemical vapor deposition (MOCVD), molecular beam epitaxy (MBE) or hydride vapor phase epitaxy (HVPE); for example, by organic metal chemical vapor deposition, the substrate 1 is placed in an organic chemical vapor deposition furnace, and the alkyl compound vapor of the III group metal element and the non-metallic hydride gas are introduced to generate III-V group compounds through thermal decomposition reaction at high temperature, and a stacked structure of an N-type semiconductor layer 2, a light-emitting layer 3, and a P-type semiconductor layer 4 is grown in sequence on the front side of the substrate 1 through deposition. The N-type semiconductor layer 2 and the P-type semiconductor layer 4 are III-V compound semiconductor materials, including at least AlxGayIn(1-xy)N or AlxGayIn(1-xy)P, wherein 0≤x≤1, 0≤y≤1, and 0≤x+y≤1. For example, the compound semiconductor may contain any one of GaN, AlN, AlGaN, GaInN, InN, AlGaInN, GaP, AlP, AlGaP, GaInP, InP, and AlGaInP; the light-emitting layer is a single quantum well structure or a multiple quantum well structure, a quantum dot structure, or a quantum wire structure.

[0030] S2, forming a P electrode 5 on the P-type semiconductor layer 4; the P electrode 5 is formed by sputtering or evaporation;

[0031] S3, according to the epitaxial layer structure grown in step S1, the thickness of the N-type semiconductor layer 2 is determined to be X, the thickness from the bottom of the N-type semiconductor layer 2 to the top of the P-type semiconductor layer 4 is Y, and the total thickness of the light-emitting layer 3 and the P-type semiconductor layer 4 is Z, then the position of the N-electrode 6 is set within a range of YZ to Y from the top of the P-type semiconductor layer 4;

[0032] For example, the thickness of the N-type semiconductor layer 2 is 2.5um, the total thickness of the light-emitting layer 3 and the P-type semiconductor layer 4 is 0.5um, and the thickness from the bottom of the N-type semiconductor layer 2 to the top of the P-type semiconductor layer 4 is 3um. The position of the N-electrode 6 is set within the range of 0.5-3um from the top of the P-type semiconductor layer 4. In this way, the N-type semiconductor layer 2 can be quickly positioned by physically measuring the thickness.

[0033] S4. The N electrode 6 is manufactured by side sputtering or evaporation within the position range of the N electrode 6 determined in step S3. After the manufacturing is completed, it is ground and split into core particles 7, and then the core particles 7 are split one by one into single LEDs; preferably, the N electrode is manufactured by evaporation and obtained by liff-off process; the N electrode can be an electrode of Cr / Al / Ti or other structures.

[0034] The present invention improves the complicated etching process required for LED production in the prior art, and innovatively proposes a positioning means for the N-type semiconductor layer. The positioning method physically measures the thickness according to the growth of the epitaxial layer structure. The measuring method is simple, and the positioning method is accurate and efficient. After the positioning step of the N-type semiconductor layer is completed, an N electrode is made on the side of the positioning position. The present invention can be achieved by making the N electrode completely or partially on the side of the positioning position. The overall process of the method for making an LED chip of the present invention can avoid the etching process steps in the conventional LED chip production process, prevent etching from damaging the epitaxial layer, simplify the operation process, improve work efficiency, reduce the loss of LED light emission, reduce the LED production cost, and is conducive to promotion and application in the industry.

[0035] Example 2

[0036] The method for manufacturing LED chips without etching in embodiment 2 of the present invention comprises the following steps:

[0037] S1. On the front side of the substrate 1, an epitaxial layer structure of an N-type semiconductor layer 2, a light-emitting layer 3, and a P-type semiconductor layer 4 is sequentially grown; wherein the material of the substrate 1 is aluminum nitride, and the epitaxial layer is stacked by an organic metal chemical vapor deposition method (MOCVD method);

[0038] S2, forming a P electrode 5 on the P-type semiconductor layer 4; the P electrode 5 is formed by a vapor deposition method;

[0039] S3, according to the epitaxial layer structure grown in step S1, the thickness of the N-type semiconductor layer 2 is determined to be 4.5 um, the thickness from the bottom of the N-type semiconductor layer 2 to the top of the P-type semiconductor layer 4 is 5.3 um, and the total thickness of the light-emitting layer 3 and the P-type semiconductor layer 4 is 0.8 um, then the position of the N-electrode 6 is set within a range of 0.8 to 5.3 um from the top of the P-type semiconductor layer 4;

[0040] S4, manufacturing the N electrode 6 on the side within the position range of the N electrode 6 determined in step S3: Figure 3 As shown, S41, the epitaxial layer structure of the manufactured P electrode 5 is split into bar-shaped core particles 7;

[0041] S42, after fixing the core particle 7 sideways, perform evaporation in the area of ​​0.8 to 5.3 um, and obtain the N electrode 6 through the lift-off process; the N electrode 6 can be an electrode of Cr / Al / Ti or other structures; then split the core particles 7 one by one into single LEDs.

[0042] Example 3

[0043] An LED chip is manufactured by the method for manufacturing an LED chip without etching according to embodiment 2 of the present invention.

[0044] When the above-mentioned embodiment of the present invention is specifically produced, it also includes other process optimization steps, such as cleaning steps, detection steps, wire bonding steps and dicing steps, but these steps are all common knowledge in the field of LED chip production. In addition, the production methods not specifically elaborated in this article also belong to the common knowledge and conventional technical means in the field of LED chip production, so they will not be described in detail in this article.

[0045] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for manufacturing LED chips without etching, characterized in that: The steps include: S1, sequentially growing an epitaxial layer structure of an N-type semiconductor layer, a light-emitting layer, and a P-type semiconductor layer on the front side of the substrate; S2, making a P electrode on the top of the P-type semiconductor layer; S3, according to the epitaxial layer structure grown in step S1, the thickness of the N-type semiconductor layer is determined to be X, the thickness from the bottom of the N-type semiconductor layer to the top of the P-type semiconductor layer is Y, and the total thickness of the light-emitting layer and the P-type semiconductor layer is Z, then the position of the N electrode is set within a range of YZ to Y from the top of the P-type semiconductor layer; S4, making an N electrode on the side within the position range of the N electrode determined in step S3; The side-forming N-electrode in step S4 includes the following steps: S41, splitting the epitaxial layer structure of the manufactured P electrode into core particles; S42, after fixing the core particle sideways, make an N electrode in the YZ~Y region.

2. The method for manufacturing LED chips without etching as claimed in claim 1, characterized in that: The material of the substrate is selected from any one of sapphire, silicon carbide, silicon, gallium nitride, ZnO, aluminum nitride and spinel.

3. The method for manufacturing LED chips without etching as claimed in claim 2, characterized in that: The epitaxial layer is stacked by using an organic metal chemical vapor deposition method, a molecular beam epitaxy method or a hydride vapor phase epitaxy method.

4. The method for manufacturing LED chips without etching as claimed in claim 3, characterized in that: The P electrode and the N electrode are made by sputtering or evaporation.

5. The method for manufacturing LED chips without etching as claimed in claim 4, characterized in that: The light-emitting layer is a single quantum well structure or a multi-quantum well structure, a quantum dot structure or a quantum wire structure.

6. The method for manufacturing LED chips without etching as claimed in claim 5, characterized in that: The N electrode is an electrode with a Cr / Al / Ti structure or other structures.

7. The method for manufacturing LED chips without etching as claimed in claim 6, characterized in that: In the step S41, the epitaxial layer structure is split into bar-shaped core particles.

8. An LED chip, characterized in that: The LED chip is manufactured by the method for manufacturing an LED chip without etching as described in any one of claims 1 to 7.

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