CN110205681A - Indium arsenide single-chip dislocation corrosion liquid and dislocation corrosion detecting method - Google Patents

Abstract

The invention relates to an indium arsenide single wafer dislocation etching solution and a dislocation corrosion detection method, which relate to the technical field of defect detection. The indium arsenide single wafer dislocation etching solution is mainly composed of hydrochloric acid, sulfuric acid and water. The raw materials of the dislocation etching solution provided by the invention are cheap, easy to obtain, and have high corrosion efficiency. The present invention also provides a method for detecting dislocation corrosion by using the above-mentioned dislocation etching solution, which includes the following steps: placing an indium arsenide single wafer in the etching solution, and performing etching to obtain a dislocation-etched indium arsenide single wafer, The surface of the indium arsenide single wafer that has been etched by dislocations is cleaned, and then observed. The dislocation corrosion detection method provided by the invention has simple operation and high corrosion efficiency, and can quickly and clearly display the dislocation in the indium arsenide single wafer.

Description

Indium Arsenide Single Wafer Dislocation Etching Solution and Dislocation Etching Detection Method

technical field

The invention relates to the technical field of defect detection, in particular to an indium arsenide single wafer dislocation etching liquid and a dislocation etching detection method.

Background technique

Infrared detectors are one of the core optoelectronic devices of infrared systems. At present, infrared detection technology is in the critical period from the second-generation two-dimensional staring focal plane array (FPA) area array imaging system to the third-generation FPA imaging system. The third-generation system It will have the characteristics of large size, high pixel density and multi-wavelength detection. Due to the shortcomings of the current commercial infrared detector material HgCdTe, such as poor crystal structure integrity, low operating temperature and small substrate size, its large-scale development and application are limited. Compared with it, InAs/GaSb II superlattice materials have the advantages of low Auger recombination rate, long carrier lifetime and good material uniformity, and become ideal materials for the preparation of large-scale focal plane arrays.

Indium arsenide is used as the source and substrate material for the production of new infrared detectors and lasers. It is easy to generate high-density dislocation defects during the crystal growth process. During the epitaxial growth process, this will be used as the starting point to generate stress and affect the epitaxial film. Growth quality on the substrate. The dislocation density of single crystal materials has a decisive impact on the performance of epitaxially grown devices, so it is necessary to conduct in-depth research on dislocations in indium arsenide.

Contents of the invention

In view of this, the main purpose of the present invention is to provide an indium arsenide single wafer dislocation etching solution and a dislocation etching detection method, in order to at least partially solve at least one of the above-mentioned technical problems.

As the first aspect of the present invention, an indium arsenide single wafer dislocation etching solution is provided, which is mainly composed of hydrochloric acid, sulfuric acid and water.

As a second aspect of the present invention, a method for detecting dislocation corrosion using the above dislocation corrosion solution is provided, comprising the following steps:

Etching the indium arsenide single wafer in an etching solution to obtain a dislocation-etched indium arsenide single wafer;

After cleaning the surface of the indium arsenide single wafer that has been etched by dislocations, the indium arsenide single wafer is observed.

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

(1) The dislocation etching solution provided by the present invention has a better selective etching effect on an indium arsenide single wafer, and the raw material is cheap and easy to obtain, and the etching efficiency is high.

(2) The dislocation corrosion detection method provided by the present invention is simple to operate, has high corrosion efficiency, and can quickly and clearly display dislocations in an indium arsenide single wafer. After dislocation corrosion testing, the dislocation density of the indium arsenide single crystal grown by the liquid-sealed Czochralski technique is about 10 ⁴ cm ^-2 , which can meet the high-quality requirements for the substrate material.

Description of drawings

Fig. 1 is a flowchart of a method for detecting dislocation corrosion of an indium arsenide single wafer clearly shown in the present invention;

Fig. 2 is the surface photo of the indium arsenide single wafer of embodiment 1 of the present invention after dislocation etching;

3 is a photo of the surface of the indium arsenide single wafer of Example 2 of the present invention after dislocation etching;

4 is a photo of the surface of the indium arsenide single wafer of embodiment 3 of the present invention after dislocation etching;

Fig. 5 is the surface photo of the indium arsenide single wafer of comparative example 1 of the present invention after dislocation etching;

6 is a photo of the surface of the indium arsenide single wafer of Comparative Example 2 of the present invention after dislocation etching.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

The invention discloses an indium arsenide single wafer dislocation etching solution, which mainly consists of hydrochloric acid, sulfuric acid and water.

The raw materials of the dislocation etching solution provided by the invention are cheap, easy to obtain, and have high corrosion efficiency.

Further, by volume fraction, the volume ratio of hydrochloric acid, sulfuric acid and water in the corrosion solution is (1-10): (0-2): (0-1);

Wherein, the mass concentration of hydrochloric acid is 36-38%, and the mass concentration of sulfuric acid is 70-98%.

Further, the single indium arsenide wafer is an indium arsenide single wafer with a {100} crystal orientation.

Further, the water is deionized water.

The invention also discloses a method for detecting dislocation corrosion by using the above dislocation corrosion solution, which includes the following steps:

Step A: Etching the indium arsenide single wafer in an etching solution to obtain a dislocation-etched indium arsenide single wafer;

Step B: cleaning the surface of the indium arsenide single wafer after dislocation etching, and then observing the dislocation density of the indium arsenide single wafer.

Further, the corrosion temperature is 10-50°C, preferably 20°C.

Further, the etching time is 1-20 min, preferably 4 min.

Further, the specific operation of step B is: wash the indium arsenide single wafer that has completed the dislocation etching with water for 5-8 times, then dry the surface of the wafer with nitrogen, and detect the dislocation density under a metallographic microscope;

Preferably, the water is deionized water.

Further, the method for detecting dislocation corrosion also includes the step of pretreating the indium arsenide single crystal before etching, which specifically includes the following steps:

Wash the polished indium arsenide single wafer with organic solvent and water in order to remove the contamination on the surface, after washing with water, blow dry the wafer with nitrogen gas for later use;

Further, the organic solvent is acetone and/or absolute ethanol; the water is deionized water.

The technical solution of the present invention will be further elaborated below through specific embodiments in conjunction with the accompanying drawings. It should be noted that the following specific embodiments are only for illustration, and the protection scope of the present invention is not limited thereto.

The chemicals and raw materials used in the following examples are all commercially available or self-made through known preparation methods.

Example 1

An etching method for detecting dislocation corrosion of a {100} indium arsenide single wafer, the etching solution is composed of analytically pure AR grade hydrochloric acid, analytically pure AR grade sulfuric acid and deionized water, and the volume ratio is 1:2:1;

Wherein, the mass concentration of hydrochloric acid is 36.5%, and the mass concentration of sulfuric acid is 96%.

The method for detecting the dislocation corrosion of the polished {100} crystal-oriented indium arsenide single wafer by using the above-mentioned etching solution comprises the following steps:

(1) Use hydrochloric acid, sulfuric acid and deionized water to prepare dislocation corrosion solution at room temperature. During the preparation process, constant stirring is required to fully mix the solution;

(2) Wash the polished indium arsenide single wafer successively with acetone, absolute ethanol and deionized water to remove the contamination on the surface, and dry the wafer with nitrogen gas after rinsing with deionized water;

(3) Put the dried indium arsenide single wafer into a dry basket, and slowly put it into the prepared etching solution for 3 minutes;

(4) Quickly take out the indium arsenide single wafer that has completed the dislocation etching, and wash it with deionized water for 5-8 times, then dry the surface of the wafer with nitrogen gas, and detect the dislocation density under a metallographic microscope.

In this embodiment, the dislocation-etched indium arsenide single wafer is placed under a metallographic microscope, and when magnified 200 times, a picture as shown in FIG. 2 can be observed, and obvious corrosion pits can be seen in the figure. According to statistics, the dislocation density is about 10120/cm ² .

Example 2

An etching method for detecting dislocation corrosion of a {100} indium arsenide single wafer, the etching solution is composed of analytically pure AR grade hydrochloric acid, analytically pure AR grade sulfuric acid and deionized water, and the volume ratio is 2:1:1;

Wherein, the mass concentration of hydrochloric acid is 36.5%, and the mass concentration of sulfuric acid is 96%.

The method for detecting the dislocation corrosion of the polished {100} crystal-oriented indium arsenide single wafer by using the above-mentioned etching solution comprises the following steps:

(1) Use hydrochloric acid, sulfuric acid and deionized water to prepare dislocation corrosion solution at room temperature. During the preparation process, constant stirring is required to fully mix the solution;

(2) Wash the polished indium arsenide single wafer successively with acetone, absolute ethanol and deionized water to remove the contamination on the surface, and dry the wafer with nitrogen gas after rinsing with deionized water;

(3) Put the dried indium arsenide single wafer into a dry basket, and slowly put it into the prepared etching solution for 2 minutes;

(4) Quickly take out the indium arsenide single wafer that has completed the dislocation etching, and wash it with deionized water for 5-8 times, then dry the surface of the wafer with nitrogen gas, and detect the dislocation density under a metallographic microscope.

In this embodiment, the dislocation-etched indium arsenide single wafer is placed under a metallographic microscope, and when magnified 200 times, a picture as shown in FIG. 3 can be observed, and obvious corrosion pits can be seen in the figure. According to statistics, the dislocation density is about 98765/cm ² .

Example 3

The content of this example is basically the same as that of Example 1, except that the corrosion solution is composed of analytically pure AR grade hydrochloric acid and deionized water, and the volume ratio is 10:1;

Wherein, the mass concentration of hydrochloric acid is 36.5%.

The method for detecting the dislocation corrosion of the polished {100} crystal-oriented indium arsenide single wafer by using the above-mentioned etching solution comprises the following steps:

(1) Use hydrochloric acid and deionized water to prepare the dislocation corrosion solution at room temperature. During the preparation process, constant stirring is required to fully mix the solution;

(2) Wash the polished indium arsenide single wafer successively with acetone, absolute ethanol and deionized water to remove the contamination on the surface, and dry the wafer with nitrogen gas after rinsing with deionized water;

(3) Put the dried indium arsenide single wafer into a dry basket, slowly put it into the prepared etching solution, and the etching time is 4 minutes;

(4) Quickly take out the indium arsenide single wafer that has completed the dislocation etching, and wash it with deionized water for 5-8 times, then dry the surface of the wafer with nitrogen gas, and detect the dislocation density under a metallographic microscope.

In this embodiment, the dislocation-etched indium arsenide single wafer is placed under a metallographic microscope, and when magnified 200 times, a picture as shown in FIG. 4 can be observed, and obvious corrosion pits can be seen in the figure. According to statistics, the dislocation density is about 11865/cm ² .

The pictures of dislocation etching in Examples 1-3 are shown in Figures 2-4. The present invention combines theory and practice, and according to the basic principle of preferential etching, successfully obtains a method for etching {100} oriented indium arsenide single wafers.

Comparative example 1

As a comparative example, a corrosion solution composed of nitric acid, hydrofluoric acid and deionized water was prepared with a volume ratio of 2:1:1;

Wherein, the mass concentration of nitric acid is 65%, and the mass concentration of hydrofluoric acid is 40%.

Using the above etching solution to conduct a dislocation corrosion experiment on a polished {100} oriented indium arsenide single wafer, including the following steps:

(1) Use nitric acid, hydrofluoric acid and deionized water to prepare the dislocation corrosion solution at room temperature. During the preparation process, constant stirring is required to fully mix the solution;

(2) Wash the polished indium arsenide single wafer successively with acetone, absolute ethanol and deionized water to remove the contamination on the surface, and dry the wafer with nitrogen gas after rinsing with deionized water;

(3) Put the dried indium arsenide single wafer into a dry basket, and slowly put it into the prepared etching solution for 2 minutes;

(4) Quickly take out the indium arsenide single wafer that has completed the dislocation etching, and wash it with deionized water for 5-8 times, then dry the wafer surface with nitrogen gas, and observe the wafer surface under a metallographic microscope.

In this example, the corroded indium arsenide single wafer is placed under a metallographic microscope, and when the magnification is 100 times, the picture shown in Figure 5 can be observed, in which some pits of different sizes and inconsistent orientations can be seen. , the shape and orientation of these pits do not conform to the basic law of consistent orientation of dislocation pits, so these pits are not dislocation pits. Therefore, the etching solution composed of nitric acid, hydrofluoric acid and deionized water is not an effective etchant for effectively etching {100} oriented InAs single crystals.

Comparative example 2

As a comparative example, a corrosion solution composed of nitric acid, hydrochloric acid and deionized water was prepared with a volume ratio of 2:1:1;

Wherein, the mass concentration of nitric acid is 65%, and the mass concentration of hydrochloric acid is 36.5%.

Using the above etching solution to conduct a dislocation corrosion experiment on a polished {100} oriented indium arsenide single wafer, including the following steps:

(1) Use nitric acid, hydrochloric acid and deionized water to prepare dislocation corrosion solution at room temperature. During the preparation process, constant stirring is required to fully mix the solution;

(2) Wash the polished indium arsenide single wafer successively with acetone, absolute ethanol and deionized water to remove the contamination on the surface, and dry the wafer with nitrogen gas after rinsing with deionized water;

(3) Put the dried indium arsenide single wafer into a dry basket, and slowly put it into the prepared etching solution for 2 minutes;

(4) Quickly take out the indium arsenide single wafer that has completed the dislocation etching, and wash it with deionized water for 5-8 times, then dry the wafer surface with nitrogen gas, and observe the wafer surface under a metallographic microscope.

In this comparative example, the dislocation-etched indium arsenide single wafer is placed under a metallographic microscope, and when magnified 100 times, the picture shown in Figure 6 can be observed, in which some rings of different sizes can be seen Shaped shallow pits, these pits are of different sizes and blurred boundaries, not dislocation pits. Therefore, the etching solution composed of nitric acid, hydrochloric acid and deionized water is not an effective etchant for effectively etching {100} oriented indium arsenide single crystals.

The specific embodiments described above have further described the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above descriptions are only specific embodiments of the present invention, and are not intended to limit the present invention. Within the spirit and principles of the present invention, any modifications, equivalent replacements, improvements, etc., shall be included in the protection scope of the present invention.

Claims (10)

1. a kind of indium arsenide single-chip dislocation corrosion liquid, which is characterized in that be mainly made of hydrochloric acid, sulfuric acid and water.

2. indium arsenide single-chip dislocation corrosion liquid according to claim 1, which is characterized in that volume fraction is pressed, it is described The volume ratio of hydrochloric acid, sulfuric acid and water is (1-10): (0-2): (0-1) in corrosive liquid；

Wherein, the mass concentration of hydrochloric acid is 36-38%, and the mass concentration of the sulfuric acid is 70-98%.

3. indium arsenide single-chip dislocation corrosion liquid according to claim 1, which is characterized in that the indium arsenide single-chip is { 100 } the indium arsenide single-chip of crystal orientation.

4. indium arsenide single-chip dislocation corrosion liquid according to claim 1, which is characterized in that the water is deionized water.

5. a kind of carry out dislocation corrosion detection using indium arsenide single-chip dislocation corrosion liquid according to any one of claims 1-4 Method, which comprises the steps of:

Indium arsenide single-chip is placed in corrosive liquid and is corroded, the indium arsenide single-chip after obtaining dislocation corrosion；

After the surface for completing the indium arsenide single-chip of dislocation corrosion is cleaned, then indium arsenide single-chip is seen It examines.

6. dislocation corrosion detecting method according to claim 5, which is characterized in that corrosion temperature is 10-50 DEG C, preferably 20℃。

7. dislocation corrosion detecting method according to claim 5, which is characterized in that etching time 1-20min, preferably 4min。

8. dislocation corrosion detecting method according to claim 5, which is characterized in that described the step of being cleaned to surface It include: to wash with water the indium arsenide single-chip for completing dislocation corrosion 5-8 times, then with being dried with nitrogen wafer surface；

The step of observation includes: the dislocation density that indium arsenide single-chip is detected under metallographic microscope；

Preferably, the water is deionized water.

9. dislocation corrosion detecting method according to claim 5, which is characterized in that further include before being corroded to institute It states indium arsenide single-chip and carries out pretreated step, the pretreated step includes:

It successively uses organic solvent and water to clean the indium arsenide single-chip after polishing, the contamination on surface is dispelled, after washing with water Chip dried up using nitrogen spare.

10. dislocation corrosion detecting method according to claim 9, which is characterized in that the organic solvent be acetone and/or Dehydrated alcohol；The water is deionized water.