阅读说明：本技术 全无机卤化物钙钛矿CsPbBr3晶片表面二次相颗粒显现方法 (All-inorganic halide perovskite CsPbBr3Method for showing secondary phase particles on surface of wafer ) 是由 程渊博 徐亚东 孙啟皓 王方宝 张滨滨 朱孟花 杨文慧 介万奇 于 2020-11-19 设计创作，主要内容包括：本发明涉及一种全无机卤化物钙钛矿CsPbBr-3晶片表面二次相颗粒显现方法,选用MgO和无水乙醇作为抛光液,多次抛光后获得光滑、平整、无划痕的表面。将抛光后的晶片在体积分数为5-20％的氢溴酸乙醇溶液中腐蚀后用无水乙醇除去表面残留腐蚀液,最后用高纯氮气吹干。最后,使用SEM和EDS实现对二次相颗粒形貌、尺寸、分布和组分特征等参数的精确表征。本发明用氢溴酸乙醇溶液对晶片表面进行腐蚀,晶体中镶嵌分布的二次相颗粒轮廓完整显现,实现对二次相颗粒形貌、尺寸、分布和组分参数的直接观察和精确表征,以及研究二次相颗粒对晶体性能的影响。该方法可以应用于CsPbBr-3晶片抛光和二次相颗粒研究领域。(The invention relates to an all-inorganic halide perovskite CsPbBr 3 Secondary phase particle manifestation on wafer surfaceThe method selects MgO and absolute ethyl alcohol as polishing solution, and obtains a smooth, flat and scratch-free surface after multiple times of polishing. Corroding the polished wafer in 5-20% hydrobromic acid ethanol solution by volume fraction, removing residual corrosive liquid on the surface by using absolute ethanol, and finally drying by using high-purity nitrogen. Finally, accurate characterization of parameters such as morphology, size, distribution and composition characteristics of secondary phase particles was achieved using SEM and EDS. According to the invention, the hydrobromic acid ethanol solution is used for corroding the surface of the wafer, the contour of secondary phase particles inlaid and distributed in the crystal is completely displayed, the direct observation and accurate characterization of the morphology, size, distribution and component parameters of the secondary phase particles are realized, and the influence of the secondary phase particles on the crystal performance is researched. The method can be applied to CsPbBr 3 Wafer polishing and secondary phase particle research.)

1. All-inorganic halide perovskite CsPbBr₃The method for showing the secondary phase particles on the surface of the wafer is characterized by comprising the following steps of:

step 1: placing No. 5000 abrasive paper on a polishing disc, placing a wafer on the abrasive paper, dropwise adding absolute ethyl alcohol with analytical purity of 99.7%, pressing the wafer for polishing, changing the other surface of the wafer, adding the absolute ethyl alcohol, pressing the wafer for polishing, then cleaning with the absolute ethyl alcohol, and drying with high-purity nitrogen;

step 2: the method comprises the following steps of (1) sticking a grinding pad on a polishing disc, dropwise adding absolute ethyl alcohol with analytical purity of 99.7%, uniformly scattering magnesium oxide (MgO) particles on the absolute ethyl alcohol with analytical purity, then placing a wafer, pressing the wafer for grinding and polishing, then changing the other surface, adding the absolute ethyl alcohol and the magnesium oxide (MgO) particles, pressing the wafer for grinding and polishing, then cleaning with the absolute ethyl alcohol, and drying with high-purity nitrogen;

and step 3: the grinding pad is adhered to a polishing disc, absolute ethyl alcohol with analytical purity of 99.7% is dripped, after the wafer is pressed for grinding and polishing, the other surface of the wafer is replaced with the absolute ethyl alcohol, then the wafer is pressed for grinding and polishing, then the wafer is cleaned by the absolute ethyl alcohol, and high-purity nitrogen is blown and dried;

and 4, step 4: preparing a hydrobromic acid ethanol solution with volume fraction of 5-20% by using analytically pure 99.7% absolute ethanol and 40-48% hydrobromic acid as an etching solution, etching the polished wafer in the etching solution for 3-15min, removing residual solution on the surface of the wafer by using the absolute ethanol after etching, and drying the wafer by using high-purity nitrogen slow airflow;

and (3) using SEM and EDS to realize accurate characterization of the feature parameters of the morphology, the size, the distribution and the composition of the secondary phase particles on the surface of the wafer.

2. The all-inorganic halide perovskite CsPbBr of claim 1₃The method for showing the secondary phase particles on the surface of the wafer is characterized by comprising the following steps: the grinding and polishing mode is as follows: and pressing the wafer to draw 8 characters at a constant speed for grinding and polishing.

3. The all-inorganic halide perovskite CsPbBr of claim 1₃The method for showing the secondary phase particles on the surface of the wafer is characterized by comprising the following steps: the polishing time obtained in the step 1 is 150- & ltwbr & gt and 300 seconds.

4. The method of claim 1All-inorganic halide perovskite CsPbBr₃The method for showing the secondary phase particles on the surface of the wafer is characterized by comprising the following steps: the particle size of the magnesium oxide MgO particles is 3 μm.

5. The all-inorganic halide perovskite CsPbBr of claim 1₃The method for showing the secondary phase particles on the surface of the wafer is characterized by comprising the following steps: the polishing time of the step 2 is 300-800 seconds.

6. The all-inorganic halide perovskite CsPbBr of claim 1₃The method for showing the secondary phase particles on the surface of the wafer is characterized by comprising the following steps: the polishing time in the step 3 is 100-200 seconds.

7. The all-inorganic halide perovskite CsPbBr of claim 1₃The method for showing the secondary phase particles on the surface of the wafer is characterized by comprising the following steps: the polishing disks ground and polished in the three steps are different polishing disks.

8. The all-inorganic halide perovskite CsPbBr of claim 1₃The method for showing the secondary phase particles on the surface of the wafer is characterized by comprising the following steps: in the step 1, the absolute ethyl alcohol dripped between the sand paper and the wafer is 2-5 ml.

9. The all-inorganic halide perovskite CsPbBr of claim 1₃The method for showing the secondary phase particles on the surface of the wafer is characterized by comprising the following steps: and in the step 2, the absolute ethyl alcohol dropped between the grinding pad and the wafer is less than 1 ml.

10. The all-inorganic halide perovskite CsPbBr of claim 1₃The method for showing the secondary phase particles on the surface of the wafer is characterized by comprising the following steps: and 3, 5-10 ml of absolute ethyl alcohol is dripped between the grinding pad and the wafer in the step 3.

Technical Field

The invention belongs to a method for showing secondary phase particles on the surface of an all-inorganic lead halide perovskite wafer, and relates to an all-inorganic halide perovskite CsPbBr₃A method for showing secondary phase particles on the surface of a wafer.

Background

All-inorganic lead halide perovskite material CsPbBr₃The method has wide application in the fields of high-efficiency photovoltaic cells, light-emitting diodes, photoelectric detectors, lasers and the like. At the same time, CsPbBr₃The method meets the requirements of room-temperature nuclear radiation detectors on materials, and shows great application potential and advantages in the field of high-energy ray detection. The preparation of fully inorganic halide perovskite CsPbBr is generally carried out by the solution method (inverse temperature crystallization method) and the melt method (Bridgman method)₃A single crystal. However, CsBr and PbBr are used₂Preparation of CsPbBr as raw Material₃It is extremely difficult to avoid the by-product CsPb₂Br₅And Cs₄PbBr₆The so-called secondary phase particles. Presence of secondary phase particlesThe transport performance of carriers in the crystal, the surface state of the prepared device, leakage current and the like can be obviously influenced. However, the optical forbidden band width is larger than that of the substrate, so that the conventional infrared transmission imaging technology cannot be directly observed. Therefore, the invention discloses a method for directly observing CsPbBr₃Method for researching formation of secondary phase particles and pairs CsPbBr thereof in crystals₃The influence of the photoelectric property of the material is important to improve the preparation technology of the device.

In general, solution methods for CsPbBr preparation₃During the crystal process, the crystal is grown by spontaneous nucleation. Due to the difference of growth conditions, the prepared crystal presents different forms, which is not beneficial to the preparation of the nuclear radiation detection device. Large size ingots produced by the melt process also require cutting and dicing to produce devices of a particular size. A large number of defects exist on the surface of the grown crystal and the surface of the cut crystal, and the defects comprise enrichment of grown-state macro-structure defects on the surface, surface contamination, surface damage caused by cutting and the like. The wafer is polished to obtain a smooth and clean surface, interference factors during surface observation and phase identification can be reduced, the surface state is effectively improved, and the leakage current of a device is reduced. The research on the crystal surface polishing treatment is reported more, and the corresponding polishing solution and polishing method are usually selected according to the material type.

For a semiconductor material CdZnTe crystal having the same soft and brittle characteristics, document 1: chinese patent 'CN 201710277234.4' discloses a surface treatment method for a CdZnTe planar detector, which respectively selects MgO and fine polishing liquid as polishing liquid to obtain a smooth, flat and scratch-free crystal surface, and then effectively reduces the surface leakage current of a CdZnTe wafer and improves the energy resolution ratio through corrosion and passivation. However, the full inorganic lead halide perovskite semiconductor CsPbBr₃The reaction with water, a common solvent, can cause difficulty in subsequent surface processing of the crystal. Currently, CsPbBr₃No relevant report is reported on the selection of the polishing liquid and the polishing method for crystal surface treatment.

The secondary phase particles are embedded and distributed in the crystal, and direct observation cannot be realized on the polished smooth crystal surface, so that further process treatment is required. Due to the fact thatSecondary phase particles and CsPbBr₃The structure constants of the crystals are greatly different, a large number of mismatch defects exist at the contact interface of the crystals and the crystals, and the crystals have high chemical activity. By selecting a specific corrosion solution, preferential corrosion is realized at the contact interface between the two solutions, so that the outline of the secondary phase particles is completely displayed. And through a Scanning Electron Microscope (SEM) and an energy spectrometer (EDS), the precise analysis and characterization of parameters such as the morphology, the size, the distribution, the component characteristics and the like of the secondary phase particles are expected to be realized, and the research on the formation mechanism and the performance influence of the secondary phase particles is finally facilitated.

Document 2: "Saidaminov M I, Haque M A, Almutlaq J, et al, organic lead halide period crystals phase-selective low temperature growth, carrier transport properties, and self-powered photodetection [ J]The use of CsBr and PbBr was investigated in Advanced Optical Materials,2017,5(2):1600704 ″₂Preparation of CsPbBr as raw Material₃And in the process of crystallization, the types and the contents of products corresponding to different raw material ratios are different. However, in the report, the by-product components and contents in the preparation process are represented by powder X-ray diffraction, the accuracy and precision are greatly limited, and secondary phase particles cannot be directly observed.

Disclosure of Invention

Technical problem to be solved

In order to avoid the defects of the prior art, the invention provides an all-inorganic halide perovskite CsPbBr₃Method for developing secondary phase particles on wafer surface in CsPbBr₃After wafer polishing, CsPbBr was treated with an ethanol hydrobromic acid solution₃And etching the surface of the wafer, and cleaning the surface of the wafer by using absolute ethyl alcohol after etching is finished to remove the residual etching solution. The contact interface of the secondary phase particles and the crystals is a high defect density area and has high chemical activity, and the reaction speed of the matrix and the secondary phase particles and the corrosive solution is slow. The contact interface of the two is dissolved by corrosion preferentially, and the surface topography of the secondary phase particles is exposed. And the components and the morphological characteristics of the secondary phase particles are analyzed by adopting SEM and EDS, so that early preparation is made for researching the formation mechanism, morphological evolution and influence on the crystal performance of the secondary phase particles.

Technical scheme

All-inorganic halide perovskite CsPbBr₃The method for showing the secondary phase particles on the surface of the wafer is characterized by comprising the following steps of:

step 1: placing No. 5000 abrasive paper on a polishing disc, placing a wafer on the abrasive paper, dropwise adding absolute ethyl alcohol with analytical purity of 99.7%, pressing the wafer for polishing, changing the other surface of the wafer, adding the absolute ethyl alcohol, pressing the wafer for polishing, then cleaning with the absolute ethyl alcohol, and drying with high-purity nitrogen;

step 2: the method comprises the following steps of (1) sticking a grinding pad on a polishing disc, dropwise adding absolute ethyl alcohol with analytical purity of 99.7%, uniformly scattering magnesium oxide (MgO) particles on the absolute ethyl alcohol with analytical purity, then placing a wafer, pressing the wafer for grinding and polishing, then changing the other surface, adding the absolute ethyl alcohol and the magnesium oxide (MgO) particles, pressing the wafer for grinding and polishing, then cleaning with the absolute ethyl alcohol, and drying with high-purity nitrogen;

and step 3: the grinding pad is adhered to a polishing disc, absolute ethyl alcohol with analytical purity of 99.7% is dripped, after the wafer is pressed for grinding and polishing, the other surface of the wafer is replaced with the absolute ethyl alcohol, then the wafer is pressed for grinding and polishing, then the wafer is cleaned by the absolute ethyl alcohol, and high-purity nitrogen is blown and dried;

and 4, step 4: preparing a hydrobromic acid ethanol solution with volume fraction of 5-20% by using analytically pure 99.7% absolute ethanol and 40-48% hydrobromic acid as an etching solution, etching the polished wafer in the etching solution for 3-15min, removing residual solution on the surface of the wafer by using the absolute ethanol after etching, and drying the wafer by using high-purity nitrogen slow airflow;

and (3) using SEM and EDS to realize accurate characterization of the feature parameters of the morphology, the size, the distribution and the composition of the secondary phase particles on the surface of the wafer.

The grinding and polishing mode is as follows: and pressing the wafer to draw 8 characters at a constant speed for grinding and polishing.

The polishing time obtained in the step 1 is 150- & ltwbr & gt and 300 seconds.

The particle size of the magnesium oxide MgO particles is 3 μm.

The polishing time of the step 2 is 300-800 seconds.

The polishing time in the step 3 is 100-200 seconds.

The polishing disks ground and polished in the three steps are different polishing disks.

In the step 1, the absolute ethyl alcohol dripped between the sand paper and the wafer is 2-5 ml.

And in the step 2, the absolute ethyl alcohol dropped between the grinding pad and the wafer is less than 1 ml.

And 3, 5-10 ml of absolute ethyl alcohol is dripped between the grinding pad and the wafer in the step 3.

Advantageous effects

The invention provides an all-inorganic halide perovskite CsPbBr₃Method for showing secondary phase particles on wafer surface, used for solving CsPbBr problem₃The technical problem of direct observation of the secondary phase particles in the crystal cannot be solved. The technical scheme is that MgO and absolute ethyl alcohol are selected as polishing liquid, a wafer is not separated when the wafer is pressed by fingers and slides, and CsPbBr is drawn at uniform speed in a 8-shaped pair mode₃The two sides of the wafer are polished for 300-800 seconds respectively to obtain a smooth, flat and scratch-free surface. The CsPbBr after polishing₃Corroding the wafer in 5-20% ethanol hydrobromic acid solution for 3-15min, removing residual corrosive liquid on the surface by using absolute ethyl alcohol after corrosion, and finally drying by using high-purity nitrogen. Due to secondary phase and CsPbBr₃The difference of the structural constants is large, a large number of mismatch defects exist at the contact interface of the two, the chemical activity is high, the contact interface between the two is preferentially corroded, and the outline of the secondary phase particle is completely displayed. Finally, accurate characterization of parameters such as morphology, size, distribution and composition characteristics of secondary phase particles was achieved using SEM and EDS.

The beneficial effects are that: the method selects MgO and absolute ethyl alcohol as polishing solution, does not separate when the finger tip presses a wafer to slide, draws 8-shaped CsPbBr at uniform speed₃The two sides of the wafer are polished for 300-800 seconds respectively to obtain a smooth, flat and scratch-free surface. In CsPbBr₃After the wafer is polished, the secondary phase particles are not directly observed due to the mosaic distribution of the secondary phase particles in the crystal. The method uses ethanol hydrobromic acid solution to CsPbBr₃The surface of the wafer is corroded, and a large number of mismatch defects existing at the contact interface of the secondary phase particles and the crystal enable the contact interface and the adjacent area to have higher chemical activityAnd is preferentially corroded. The contour of the secondary phase particles which are inlaid and distributed in the crystal is completely displayed, the direct observation and the accurate characterization of the morphology, the size, the distribution and the component parameters of the secondary phase particles are realized, and the influence of the secondary phase particles on the crystal performance is researched. The method can be applied to CsPbBr₃Wafer polishing and secondary phase particle research.

Drawings

FIG. 1 is a flow chart of a method of the present invention;

FIG. 2 is CsPbBr of step 1 of example 3₃SEM image of wafer surface;

FIG. 3 is CsPbBr of step 3 of example 3₃SEM image of wafer surface;

FIG. 4 is CsPbBr of step 4 of example 3₃SEM image of wafer surface.

Detailed Description

The invention will now be further described with reference to the following examples and drawings:

all-inorganic halide perovskite CsPbBr₃The crystal surface secondary phase particle display method comprises the following steps:

step one, flatly paving a 5000# abrasive paper on a No. 1 polishing disc, dripping 2-5 ml of absolute ethyl alcohol with analytical purity of 99.7% on the abrasive paper, pressing the abrasive paper by fingers until the wafer is not separated from the finger tip when the wafer slides, drawing 8 characters at a constant speed for polishing, and cutting and scribing CsPbBr with specific size₃The two sides of the wafer are polished for 150-300 seconds respectively to obtain a flat surface, the flat surface is cleaned by absolute ethyl alcohol, and the wafer is dried by high-purity nitrogen.

Step two, flatly pasting the grinding pad on a No. 2 polishing disk, dripping less than 1 ml of analytically pure 99.7% absolute ethyl alcohol, uniformly scattering magnesium oxide (MgO) particles with the particle size of 3 mu m on the analytically pure absolute ethyl alcohol, pressing the wafer by fingers until the wafer does not separate when sliding, drawing 8 characters at a constant speed for grinding and polishing, and carrying out CsPbBr polishing on the wafer₃Polishing two surfaces of the wafer for 300-800 seconds respectively to obtain a smooth, flat and scratch-free surface, cleaning the surface by using absolute ethyl alcohol, and drying the surface by using high-purity nitrogen.

Step three, flatly pasting the grinding pad on a No. 3 polishing disk, dripping 5-10 ml of absolute ethyl alcohol with analytical purity of 99.7%, and pressing the wafer and the finger tip when the finger slidesNon-separating, uniformly drawing 8-shaped pattern, grinding and polishing to CsPbBr₃Polishing two surfaces of the wafer for 100-200 seconds respectively to remove adhesive stains on the surface of the wafer, cleaning the wafer by absolute ethyl alcohol, and drying the wafer by high-purity nitrogen.

Step four, preparing a hydrobromic acid ethanol solution with the volume fraction of 5-20% by using analytically pure 99.7% absolute ethanol and hydrobromic acid with the concentration of 40-48% as an etching solution, and using the polished CsPbBr₃Corroding the wafer in the corrosive liquid for 3-15min, removing residual solution on the surface of the wafer by using absolute ethyl alcohol after corrosion, and drying the wafer by using high-purity nitrogen slow airflow. Observation of CsPbBr after Corrosion Using SEM and EDS₃The precise characterization of the parameters such as the morphology, the size, the distribution, the component characteristics and the like of the secondary phase particles is realized on the surface of the wafer.

Example 1:

step one, flatly paving a 5000# abrasive paper on a No. 1 polishing disc, dripping 5 milliliters of absolute ethyl alcohol with analytical purity of 99.7 percent on the abrasive paper, pressing the abrasive paper by fingers until the wafer is not separated from the finger tip when the abrasive paper slides, drawing 8 characters at a constant speed for polishing, and polishing the abrasive paper with the size of 5 multiplied by 2mm³CsPbBr of₃And (3) polishing two surfaces of the wafer for 200 seconds respectively to obtain a flat crystal surface, cleaning the flat crystal surface by using absolute ethyl alcohol, and drying the flat crystal surface by using high-purity nitrogen.

Step two, flatly pasting the grinding pad on a No. 2 polishing disk, dripping less than 1 ml of analytically pure 99.7% absolute ethyl alcohol, uniformly scattering MgO particles with the particle size of 3 mu m on the analytically pure absolute ethyl alcohol, pressing the wafer by fingers until the wafer does not separate when sliding, drawing a '8' shape at a constant speed for grinding and polishing, and carrying out CsPbBr polishing on the wafer₃And (3) polishing two surfaces of the wafer for 800 seconds respectively to obtain a smooth, flat and scratch-free crystal surface, cleaning the crystal surface by using absolute ethyl alcohol, and drying the crystal surface by using high-purity nitrogen.

Step three, flatly pasting the grinding pad on a No. 3 polishing disk, dripping 5 milliliters of absolute ethyl alcohol with analytical purity of 99.7 percent, pressing the fingers until the wafer is not separated from the finger tip when the fingers slide, drawing 8 at a constant speed for grinding and polishing, and carrying out CsPbBr₃And (3) polishing two surfaces of the wafer for 150 seconds respectively to remove adhesive stains on the surface of the wafer, cleaning the wafer by using absolute ethyl alcohol, and drying the wafer by using high-purity nitrogen.

Step four, using analytically pure 99.7 percent of absolute ethyl alcohol and 48 percent of hydrogen bromidePreparing 5% hydrobromic acid ethanol solution as corrosive liquid by acid, and adding the polished CsPbBr₃And (3) standing and corroding the wafer in the corrosive liquid for 10min, removing residual solution on the surface of the wafer by using absolute ethyl alcohol after corrosion, and drying the wafer by using high-purity nitrogen slow airflow. Observation of CsPbBr after Corrosion Using SEM and EDS₃And the surface of the wafer accurately represents parameters such as the morphology, the size, the distribution, the composition characteristics and the like of secondary phase particles.

Example 2:

step one, flatly paving a 5000# abrasive paper on a No. 1 polishing disc, dripping 5 milliliters of absolute ethyl alcohol with analytical purity of 99.7 percent on the abrasive paper, pressing the abrasive paper by fingers until the wafer is not separated from the finger tip when the abrasive paper slides, drawing 8 characters at a constant speed for polishing, and polishing the abrasive paper with the size of 5 multiplied by 2mm³CsPbBr of₃And (3) polishing two surfaces of the wafer for 200 seconds respectively to obtain a flat crystal surface, cleaning the flat crystal surface by using absolute ethyl alcohol, and drying the flat crystal surface by using high-purity nitrogen.

Step two, flatly pasting the grinding pad on a No. 2 polishing disk, dripping less than 1 ml of analytically pure 99.7% absolute ethyl alcohol, uniformly scattering MgO particles with the particle size of 3 mu m on the analytically pure absolute ethyl alcohol, pressing the wafer by fingers until the wafer does not separate when sliding, drawing a '8' shape at a constant speed for grinding and polishing, and carrying out CsPbBr polishing on the wafer₃And (3) polishing two surfaces of the wafer for 800 seconds respectively to obtain a smooth, flat and scratch-free crystal surface, cleaning the crystal surface by using absolute ethyl alcohol, and drying the crystal surface by using high-purity nitrogen.

Step three, flatly pasting the grinding pad on a No. 3 polishing disk, dripping 5 milliliters of absolute ethyl alcohol with analytical purity of 99.7 percent, pressing the fingers until the wafer is not separated from the finger tip when the fingers slide, drawing 8 at a constant speed for grinding and polishing, and carrying out CsPbBr₃And (3) polishing two surfaces of the wafer for 150 seconds respectively to remove adhesive stains on the surface of the wafer, cleaning the wafer by using absolute ethyl alcohol, and drying the wafer by using high-purity nitrogen.

Step four, preparing a 15% hydrobromic acid ethanol solution by using analytically pure 99.7% absolute ethanol and 48% hydrobromic acid as an etching solution, and using the polished CsPbBr₃And (3) standing and corroding the wafer in the corrosive liquid for 10min, removing residual solution on the surface of the wafer by using absolute ethyl alcohol after corrosion, and drying the wafer by using high-purity nitrogen slow airflow. Observation of CsPbBr after Corrosion Using SEM and EDS₃Wafer surface, precise characterization ofThe morphology, size, distribution and composition characteristics of the secondary phase particles.

Example 3:

step one, flatly paving a 5000# abrasive paper on a No. 1 polishing disc, dripping 5 milliliters of absolute ethyl alcohol with analytical purity of 99.7 percent on the abrasive paper, pressing the abrasive paper by fingers until the wafer is not separated from the finger tip when the abrasive paper slides, drawing 8 characters at a constant speed for polishing, and polishing the abrasive paper with the size of 5 multiplied by 2mm³CsPbBr of₃And (3) polishing two surfaces of the wafer for 200 seconds respectively to obtain a flat crystal surface, cleaning the flat crystal surface by using absolute ethyl alcohol, and drying the flat crystal surface by using high-purity nitrogen.

Step two, flatly pasting the grinding pad on a No. 2 polishing disk, dripping less than 1 ml of analytically pure 99.7% absolute ethyl alcohol, uniformly scattering MgO particles with the particle size of 3 mu m on the analytically pure absolute ethyl alcohol, pressing the wafer by fingers until the wafer does not separate when sliding, drawing a '8' shape at a constant speed for grinding and polishing, and carrying out CsPbBr polishing on the wafer₃And (3) polishing two surfaces of the wafer for 800 seconds respectively to obtain a smooth, flat and scratch-free crystal surface, cleaning the crystal surface by using absolute ethyl alcohol, and drying the crystal surface by using high-purity nitrogen.

Step three, flatly pasting the grinding pad on a No. 3 polishing disk, dripping 5 milliliters of absolute ethyl alcohol with analytical purity of 99.7 percent, pressing the fingers until the wafer is not separated from the finger tip when the fingers slide, drawing 8 at a constant speed for grinding and polishing, and carrying out CsPbBr₃And (3) polishing two surfaces of the wafer for 150 seconds respectively to remove adhesive stains on the surface of the wafer, cleaning the wafer by using absolute ethyl alcohol, and drying the wafer by using high-purity nitrogen.

Step four, preparing a 15% hydrobromic acid ethanol solution by using analytically pure 99.7% absolute ethanol and 48% hydrobromic acid as an etching solution, and using the polished CsPbBr₃And (3) standing and corroding the wafer in the corrosive liquid for 15min, removing residual solution on the surface of the wafer by using absolute ethyl alcohol after corrosion, and drying the wafer by using high-purity nitrogen slow airflow. Observation of CsPbBr after Corrosion Using SEM and EDS₃And the surface of the wafer accurately represents parameters such as the morphology, the size, the distribution, the composition characteristics and the like of secondary phase particles.