A method for processing a gallium antimonide wafer

Abstract

This invention provides a method for processing gallium antimonide wafers, comprising: S1, cleaning the gallium antimonide wafer after slicing and cleaning to remove the cutting fluid from the surface; S2, rinsing the surface of the gallium antimonide wafer and drying it; S3, cleaning the gallium antimonide wafer with etching solution A, which is composed of an alkaline substance and an oxide; S4, cleaning the gallium antimonide wafer with etching solution B, which is composed of an acidic solution and a buffer solution; S5, rinsing the surface of the gallium antimonide wafer and drying it; S6, observing the surface of the gallium antimonide wafer under fluorescent light and marking the twin distribution. The processing method of this invention exhibits high selective etching stability, good repeatability, and controllable etching rate. The twin positions of the wafer after etching are clear and can be easily identified, thereby improving the accuracy and efficiency of wafer splitting.

Description

Technical Field

[0001] This invention relates to a compound semiconductor wafer etching process, specifically to a method for processing gallium antimonide wafers. Background Technology

[0002] Gallium antimonide is a direct bandgap semiconductor material with a bandgap of 0.725 eV at room temperature and a lattice constant of 0.6096 nm. It has a high degree of matching with some superlattices and is widely used in military and civilian fields such as lasers, detectors, high-frequency devices, and solar cells.

[0003] Currently, with the development of microelectronic and optoelectronic devices using gallium antimonide (GaS) as a substrate, higher requirements are being placed on materials. The presence of twins on the surface of GaS wafers can negatively impact the performance of epitaxial devices. However, during the processing of GaS wafers, twins can only be detected after cleaning. This leads to wafer degradation, significantly reducing their value, and necessitates recutting and reshipment. Consequently, it results in wafer loss and a waste of resources. While existing technologies include EPD etching processes for GaS, these processes primarily focus on dislocation and defect identification, failing to effectively identify twins. To improve crystal utilization and processing efficiency, new processes are urgently needed to address these issues. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a method for processing gallium antimonide wafers. The method of the present invention provides high stability, good repeatability, and controllable etching rate for gallium antimonide wafers. The etched wafers are smoother and brighter, with clear twin positions that can be easily identified, thereby improving the accuracy and efficiency of wafer breaking.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A method for processing gallium antimonide (100) wafers includes:

[0007] S1. Clean the gallium antimonide wafer after slicing and cleaning to remove the cutting fluid from the surface;

[0008] S2. Rinse the surface of the gallium antimonide wafer and dry it;

[0009] S3. The gallium antimonide wafer is cleaned using etching solution A, which is composed of an alkaline substance and an oxidant.

[0010] S4. The gallium antimonide wafer is cleaned using B etching solution, which consists of an acidic solution and a buffer solution.

[0011] S5. Rinse the surface of the gallium antimonide wafer and dry it;

[0012] S6. Observe the surface of the gallium antimonide wafer under fluorescent light and mark the twin distribution.

[0013] Preferably, in step S3, the cleaning time is 20 to 60 seconds.

[0014] Preferably, in corrosive solution A, the alkaline substance is at least one of potassium hydroxide, sodium hydroxide, and ammonia, more preferably potassium hydroxide and / or sodium hydroxide; the oxidant is at least one of hypochlorite (e.g., lithium hypochlorite, potassium hypochlorite, sodium hypochlorite), chlorate (e.g., sodium chlorate, lithium chlorate, potassium chlorate), and hydrogen peroxide, most preferably hydrogen peroxide.

[0015] Preferably, in step S3, the mass ratio of the oxidant to the alkaline substance is 2 to 5.

[0016] Preferably, in step S4, the cleaning time is 30 to 90 seconds.

[0017] Preferably, in the B corrosion solution, the acidic solution is hydrochloric acid and / or hydrofluoric acid, and the buffer solution is one or more of acetic acid, propionic acid, and butyric acid.

[0018] Preferably, in the B corrosion solution, the volume ratio of the acidic solution to the buffer solution is 1:1 to 3.

[0019] Preferably, step S6 is followed by step S7, which includes: splitting gallium antimonide into pieces according to the twin distribution.

[0020] Preferably, in step S1, the cleaning is performed using an organic reagent, such as alcohol or isopropanol, and the preferred cleaning method is ultrasonic cleaning.

[0021] Preferably, between step S3 and step S4, a step of cleaning and drying the gallium antimonide wafer is also included.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The processing technology of this invention can selectively etch the surface of gallium antimonide wafers after slicing. The etching process is controllable, and the wafer surface is clean, smoother and brighter after etching. It can clearly identify twins in gallium antimonide wafers, thus effectively removing twins and preventing twin distribution on the wafer surface. This avoids the need for rework and wafer downgrading (wafers containing twins have a significantly reduced value and can only be downgraded, and downgraded wafers need to be reprocessed for shipment). Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a process flow diagram of the present invention. Detailed Implementation

[0026] To facilitate understanding of the present invention, the invention will be described more fully and in detail below with reference to the accompanying drawings and preferred embodiments, but the scope of protection of the present invention is not limited to the following specific embodiments.

[0027] Example 1:

[0028] A method for processing gallium antimonide wafers includes the following steps:

[0029] (1) Clean the sliced ​​gallium antimonide wafer in alcohol to remove the cutting fluid from the surface;

[0030] (2) Then rinse the surface of the gallium antimonide wafer with water, and dry it after rinsing it clean;

[0031] (3) Immerse the dried gallium antimonide wafer in an etching solution with a mass ratio of sodium hypochlorite to sodium hydroxide of 2 for 50 seconds, clean the wafer with deionized water and dry it.

[0032] (4) After cleaning and drying, immerse the wafer in an etching solution with a volume ratio of hydrofluoric acid and acetic acid of 1 for 30 seconds.

[0033] (5) Then the surface of the gallium antimonide wafer was rinsed with deionized water and dried to obtain a wafer with a smoother and brighter surface;

[0034] (6) Observe the twins on the surface of the gallium antimonide wafer under fluorescent light and mark the twin distribution;

[0035] (7) Perform gallium antimonide chipping based on twin distribution.

[0036] Example 2:

[0037] A method for processing gallium antimonide wafers includes the following steps:

[0038] (1) Clean the sliced ​​gallium antimonide wafer in alcohol to remove the cutting fluid from the surface;

[0039] (2) Then rinse the surface of the gallium antimonide wafer with water, and dry it after rinsing it clean;

[0040] (3) Immerse the dried gallium antimonide wafer in an etching solution with a mass ratio of hydrogen peroxide and sodium hydroxide of 4 for 40 seconds, clean the wafer with deionized water and dry it.

[0041] (4) After cleaning and drying, immerse the wafer in an etching solution with a volume ratio of hydrochloric acid and acetic acid of 1 for 30 seconds.

[0042] (5) Then the surface of the gallium antimonide wafer was rinsed with deionized water and dried to obtain a wafer with a smoother and brighter surface;

[0043] (6) Observe the twins on the surface of the gallium antimonide wafer under fluorescent light and mark the twin distribution;

[0044] (7) Perform gallium antimonide chipping based on twin distribution.

[0045] Comparative Example 1:

[0046] A method for processing gallium antimonide wafers includes the following steps:

[0047] (1) Clean the sliced ​​gallium antimonide wafer in alcohol to remove the cutting fluid from the surface;

[0048] (2) Then rinse the surface of the gallium antimonide wafer with water, and dry it after rinsing it clean;

[0049] (3) After cleaning and drying, immerse the wafer in an etching solution with a volume ratio of hydrofluoric acid and acetic acid of 1 for 30 seconds.

[0050] (4) Then rinse the surface of the gallium antimonide wafer with deionized water and dry the gallium antimonide wafer;

[0051] (5) When observed under fluorescent light, no obvious changes were found on the surface of the gallium antimonide wafer, and twins could not be identified.

[0052] Comparative Example 2:

[0053] A method for processing gallium antimonide wafers includes the following steps:

[0054] (1) Clean the sliced ​​gallium antimonide wafer in alcohol to remove the cutting fluid from the surface;

[0055] (2) Then rinse the surface of the gallium antimonide wafer with water, and dry it after rinsing it clean;

[0056] (3) The dried gallium antimonide wafer was immersed in an etching solution with a mass ratio of hydrogen peroxide and sodium hydroxide of 4 for 40 seconds. The wafer was then cleaned with deionized water and dried to obtain a wafer with lower surface brightness.

[0057] (4) When observed under fluorescent light, the surface of the gallium antimonide wafer could not be identified as twins.

[0058] Comparative Example 3:

[0059] A method for processing gallium antimonide wafers includes the following steps:

[0060] (1) Clean the sliced ​​gallium antimonide wafer in alcohol to remove the cutting fluid from the surface;

[0061] (2) Then rinse the surface of the gallium antimonide wafer with water, and dry it after rinsing it clean;

[0062] (3) Immerse the dried gallium antimonide wafer in a 10% sodium hypochlorite solution for 40 seconds to etch it, then clean the wafer with deionized water and dry it.

[0063] (4) After cleaning and drying, immerse the wafer in an etching solution with a volume ratio of hydrochloric acid and acetic acid of 1 for 30 seconds.

[0064] (5) Then the surface of the gallium antimonide wafer was rinsed with deionized water and dried to obtain a wafer with a rougher surface and lower brightness.

[0065] (6) When the surface of the gallium antimonide wafer is observed under fluorescent light, the twin positions are blurry and difficult to identify, indicating that the selective etching effect is poor.

[0066] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for processing gallium antimonide (100) wafers, characterized in that, include: S1. Clean the sliced ​​gallium antimonide wafer to remove the cutting fluid from the surface; S2. Rinse the surface of the gallium antimonide wafer and dry it; S3. The gallium antimonide wafer is cleaned using etching solution A, which is composed of an alkaline substance and an oxidizing agent. The alkaline substance in etching solution A is at least one of potassium hydroxide, sodium hydroxide, and ammonia water. The oxidizing agent is at least one of hypochlorite, chlorate, and hydrogen peroxide. In step S3, the cleaning time is 20-50 seconds. S4. The gallium antimonide wafer is cleaned using etching solution B, which consists of an acidic solution and a buffer solution; the acidic solution is hydrochloric acid and / or hydrofluoric acid, and the buffer solution is at least one of acetic acid, propionic acid, and butyric acid; the volume ratio of the acidic solution to the buffer solution in etching solution B is 1:1 to 3; the cleaning time is 30 to 90 seconds. S5. Rinse the surface of the gallium antimonide wafer and dry it; S6. Observe the surface of the gallium antimonide wafer under fluorescent light and mark the twin distribution; S7. Perform gallium antimonide chipping based on twin distribution.

2. The method for processing gallium antimonide (100) wafers as described in claim 1, characterized in that, In the A-type corrosive solution, the mass ratio of the oxidant to the alkaline substance is 2 to 5.

3. The method for processing gallium antimonide (100) wafers as described in any one of claims 1 or 2, characterized in that, In the B corrosion solution, the volume ratio of the acidic solution to the buffer solution is 1:1 to 3.

4. The method for processing gallium antimonide (100) wafers as described in claim 1 or 2, characterized in that, In step S1, the cleaning is performed using an organic reagent; the cleaning method is ultrasonic cleaning.

5. The method for processing gallium antimonide (100) wafers as described in claim 1 or 2, characterized in that, Between step S3 and step S4, there is also a step of cleaning and drying the gallium antimonide wafer.

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