CN118777324A - A semiconductor material defect characterization system, method and related device - Google Patents

Abstract

The present application provides a defect characterization system, method and related device for semiconductor materials, the system includes a supercontinuum laser transmitter, a spectroscopic crystal, a polarizer, a first prism, a first lens, a microscope, a sample displacement stage, a second lens, a second prism, an analyzer, a slit and a computer, and the defect characterization image can be made to show the defect more clearly by the difference in optical path difference between ordinary light and extraordinary light caused by the defects on the surface of the semiconductor material. Moreover, the laser beam emitted by the supercontinuum laser transmitter has a continuous spectrum, and the spectral range may include from ultraviolet light to infrared light, so that various defects in semiconductor materials can be measured, such as deep energy level defects, shallow energy level defects and impurity defects, etc., so that various defects can be more accurately displayed in the defect characterization image, improving the comprehensiveness and accuracy of semiconductor material defect detection.

Description

A semiconductor material defect characterization system, method and related device

Technical Field

The present application relates to the field of material defect characterization, and in particular to a semiconductor material defect characterization system, method and related devices.

Background Art

The photocapacitance test method is an effective method for measuring deep energy level defects in semiconductor materials. It can measure the distribution information of deep energy level defects in semiconductor materials. However, this method can only detect the energy level position and distribution of deep energy levels, and the test method is relatively complicated. Therefore, providing a suitable semiconductor material defect characterization system and method has become a technical problem that needs to be solved urgently.

Summary of the invention

In view of this, the purpose of the present application is to provide a semiconductor material defect characterization system, method and related devices, so that various defects can be more accurately displayed in the defect characterization image, thereby improving the comprehensiveness and accuracy of semiconductor material defect detection.

The specific plan is as follows:

In one aspect, the present application provides a semiconductor material defect characterization system, comprising:

A supercontinuum laser emitter for emitting a laser beam;

On the optical path between the supercontinuum laser emitter and the spectroscopic crystal, there are a polarizer, a first prism and a first lens arranged in sequence; the polarizer is used to convert the laser beam into a first linear polarized light; the first prism is used to decompose the first linear polarized light into ordinary light and extraordinary light; the first lens is used to make the emission directions of the ordinary light and the extraordinary light parallel;

A microscope disposed on an optical path between the spectroscopic crystal and a sample displacement stage, wherein the sample displacement stage is used to place the semiconductor material, and the spectroscopic crystal is used to allow the ordinary light and the extraordinary light to be incident on the microscope so that the microscope can be focused;

On the optical path between the spectroscopic crystal and the photodetector, there are a second lens, a second prism, an analyzer and a slit arranged in sequence; the second lens is used to change the emission direction of the ordinary light and the extraordinary light reflected by the surface of the semiconductor material after passing through the spectroscopic crystal; the second prism is used to converge the ordinary light and the extraordinary light reflected by the surface of the semiconductor material into a second linearly polarized light; the slit is used to make the second linearly polarized light interfere and be incident on the photodetector; the photodetector is used to convert the received optical signal into an electrical signal;

A computer is used to display a defect representation image of the surface of the semiconductor material according to the electrical signal.

Optionally, it also includes:

A lock-in amplifier and a chopper connected to each other, wherein the lock-in amplifier is used to control the frequency of the chopper;

The chopper is located on an optical path between the first lens and the spectroscopic crystal, and is used for adjusting the ordinary light and the extraordinary light according to the frequency.

Optionally, it also includes:

The stepper motor controller connected to the sample displacement stage is used to control the movement of the sample displacement stage.

Optionally, it also includes:

A small-aperture filter located on the optical path between the supercontinuum laser emitter and the polarizer is used to purify the laser beam.

Optionally, the first prism or the second prism is a Nomarski prism.

Optionally, it also includes:

The light source and the CCD detector connected to the computer are used to calibrate the test position of the semiconductor material before detecting the semiconductor material.

In another aspect, an embodiment of the present application further provides a semiconductor material defect characterization method, which is applied to the semiconductor material defect characterization system, comprising:

Controlling the supercontinuum laser emitter to emit the laser beam;

After passing through the polarizer, the first prism and the first lens, the laser beam emits the ordinary light and the extraordinary light in parallel to the beam splitting crystal;

The ordinary light and the extraordinary light are incident on the surface of the semiconductor material after passing through the spectroscopic crystal and the microscope;

The ordinary light and the extraordinary light reflected back by the semiconductor material pass through the light splitting crystal, the second lens and the second prism to obtain the second linearly polarized light;

The second linearly polarized light interferes after passing through the analyzer and the slit, and is incident on the photodetector;

The photodetector converts the received light signal into an electrical signal;

The computer displays a defect representation image of the surface of the semiconductor material based on the electrical signal.

Optionally, before controlling the supercontinuum laser emitter to emit the laser beam, the method further includes:

The light emitted by the light source is incident on the surface of the semiconductor material after passing through the spectroscopic crystal and the microscope;

The light reflected by the surface of the semiconductor material passes through the spectroscopic crystal, the second lens and the second prism, and is then received by the CCD detector;

The CCD detector transmits the received signal to the computer so that the computer displays the surface image of the semiconductor material and marks the test position of the semiconductor material in the surface image.

In another aspect, an embodiment of the present application provides a computer device, the computer device comprising a processor and a memory:

The memory is used to store program code and transmit the program code to the processor;

The processor is configured to execute the method described above according to the instructions in the program code.

On the other hand, an embodiment of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium is used to store a computer program, and the computer program is used to execute the method described in the above aspects.

The embodiment of the present application provides a defect characterization system, method and related device for semiconductor materials, the system includes a supercontinuum laser emitter for emitting a laser beam; a polarizer, a first prism and a first lens are arranged in sequence on the optical path between the supercontinuum laser emitter and the spectroscopic crystal; the polarizer is used to convert the laser beam into a first linearly polarized light; the first prism is used to decompose the first linearly polarized light into ordinary light and extraordinary light; the first lens is used to make the emission directions of ordinary light and extraordinary light parallel; a microscope is arranged on the optical path between the spectroscopic crystal and the sample displacement stage, the sample displacement stage is used to place the semiconductor material, and the spectroscopic crystal is used to decompose the ordinary light and extraordinary light. Ordinary light is incident on a microscope so that the microscope can focus; on the optical path between the spectroscopic crystal and the photodetector, there are a second lens, a second prism, a polarizer and a slit arranged in sequence; the second prism is used to change the emission direction of ordinary light and extraordinary light reflected from the surface of the semiconductor material after passing through the spectroscopic crystal; the second prism is used to converge the ordinary light and extraordinary light reflected from the surface of the semiconductor material into second linearly polarized light; the slit is used to cause the second linearly polarized light to interfere and be incident on the photodetector; the photodetector is used to convert the received optical signal into an electrical signal; and a computer is used to display a defect characterization image of the surface of the semiconductor material according to the electrical signal.

In the embodiment of the present application, the difference in optical path difference between ordinary light and extraordinary light caused by defects on the surface of semiconductor materials can make the defect characterization image more clearly show the defects. Moreover, the laser beam emitted by the supercontinuum laser emitter has a continuous spectrum, and the spectrum range can include from ultraviolet light to infrared light, so that various defects in semiconductor materials can be measured, such as deep energy level defects, shallow energy level defects and impurity defects, etc., so that various defects can be more accurately displayed in the defect characterization image, improving the comprehensiveness and accuracy of semiconductor material defect detection.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

FIG1 is a schematic diagram showing the structure of a semiconductor material defect characterization system provided in an embodiment of the present application;

FIG2 is a schematic diagram showing a process flow of a semiconductor material defect characterization method provided in an embodiment of the present application;

FIG3 is a structural diagram of a computer device provided in an embodiment of the present application.

DETAILED DESCRIPTION

In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below with reference to the accompanying drawings.

In the following description, many specific details are set forth to facilitate a full understanding of the present application, but the present application may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

To facilitate understanding, a semiconductor material defect characterization system, method and related devices provided in an embodiment of the present application are described in detail below in conjunction with the accompanying drawings.

Referring to Figure 1, which is a schematic diagram of the structure of a defect characterization system for semiconductor materials provided in an embodiment of the present application, the system may include a supercontinuum laser emitter 1, a spectroscopic crystal 11, a polarizer 5, a first prism 6, a first lens 7, a microscope 12, a sample displacement stage 14, a second lens 15, a second prism 16, an analyzer 19, a slit and a computer 23.

In the embodiment of the present application, the supercontinuum laser emitter 1 is used to emit a laser beam so that the laser beam can be irradiated on the semiconductor material 13 to characterize the defects on the surface of the semiconductor material 13. The semiconductor material 13 can be a compound semiconductor composed of group III and V elements, such as gallium arsenide. The supercontinuum laser emitter 1 can also be recorded as a supercontinuum white light laser. The laser beam emitted by the supercontinuum laser emitter 1 has a wide continuous spectrum, and the continuous spectrum can include from ultraviolet light to infrared light.

Since the defects in semiconductor materials have many excited states, that is, there are many types of defects, such as deep energy level defects, shallow energy level defects and impurity defects, the light energy corresponding to different excited states is different. For example, some excited states require electrons to jump from the valence band to the conduction band, some excited states require electrons to jump from the valence band to the second conduction band, and some excited states require electrons to jump from the impurity energy level to the conduction band. Therefore, for defects corresponding to different excited states, appropriate light energy is needed to excite them.

In this way, since the laser beam has a very wide continuous spectrum, it can provide corresponding energy for the excitation of various excited states. Therefore, under the action of the supercontinuum laser emitter 1, various excited states on the surface of the semiconductor material can be excited, so that various defects in the semiconductor material can be measured, such as deep energy level defects, shallow energy level defects and impurity defects, etc., so that various defects can be more accurately displayed in the defect characterization image, thereby improving the comprehensiveness and accuracy of semiconductor material defect detection.

Specifically, there is a certain relationship between the bandgap width (Eg) of semiconductor materials and the wavelength (λ) of light. The bandgap width can be understood as the energy between the lowest energy level of the conduction band and the highest energy level of the valence band, which can be specifically expressed as: Eg = 1024/λ. When the light energy is greater than the bandgap width of the semiconductor material, electrons can be excited to jump from the valence band to the conduction band.

In the embodiment of the present application, on the optical path between the supercontinuum laser emitter 1 and the spectroscopic crystal 11, there are a polarizer 5, a first prism 6 and a first lens 7 arranged in sequence. The polarizer 5 is used to convert the laser beam into a first linear polarized light; the first prism 6 is used to decompose the first linear polarized light into ordinary light and extraordinary light; the first lens 7 is used to make the emission directions of ordinary light and extraordinary light parallel.

In Figure 1, the laser beam emitted by the supercontinuum laser transmitter 1 is reflected by the first plane mirror 2 and incident into the polarizer 5. The polarizer 5 can adjust the polarization state of the laser beam to make it linearly polarized light. The beam after passing through the polarizer 5 can be recorded as the first linear polarized light. The polarization direction of the first linear polarized light is the same as the transmission direction of the polarizer 5.

The first linear polarized light can be incident on the first prism 6. The first linear polarized light can have a birefringence effect in the first prism 6. The first prism 6 can decompose the first linear polarized light into ordinary light and extraordinary light, which can be recorded as o light and e light. The vibration directions of o light and e light are perpendicular to each other, and there is a certain phase difference between the two.

The o-light and the e-light are incident on the first lens 7, and the first lens 7 can make the o-light and the e-light emerge in parallel, and then be incident on the spectroscopic crystal 11 in parallel, and the spectroscopic crystal 11 can change the propagation direction of the o-light and the e-light. As an example, the first prism 6 can be a Nomarski prism, and the polarizer 5 can be a Glan Taylor prism.

In an embodiment of the present application, a microscope 12 is arranged on the optical path between the spectroscopic crystal 11 and the sample displacement stage 14. The sample displacement stage 14 is used to place a semiconductor material 13. The semiconductor material 13 can be placed on the surface of the sample displacement stage 14. The spectroscopic crystal 11 is used to allow ordinary light and extraordinary light to be incident on the microscope 12 so that the microscope 12 can focus.

That is, ordinary light and extraordinary light are incident into the microscope 12 through the spectroscopic crystal 11, and the microscope 12 can focus the ordinary light and extraordinary light that are parallel to each other, so that they are focused on the surface of the semiconductor material 13. That is, the microscope 12 can irradiate the two beams of light more finely on the surface of the semiconductor material 13 for microscopic observation. As an example, the microscope 12 can be a 50x microscope.

In the embodiment of the present application, ordinary light and extraordinary light are reflected after being incident on the surface of the semiconductor material 13, and the reflected ordinary light and extraordinary light can be emitted outward through the microscope 12 and the spectroscopic crystal 11. In the optical path between the spectroscopic crystal 11 and the photodetector 21, there are a second lens 15, a second prism 16, an analyzer 19 and a slit arranged in sequence. In FIG1 , the slit is located before the photodetector 21. As an example, the second prism 16 can be a Nomarski prism.

The second lens 15 is used to change the emission direction of the ordinary light and the extraordinary light reflected from the surface of the semiconductor material 13 after passing through the spectroscopic crystal 11, that is, after the ordinary light and the extraordinary light pass through the second lens 15, their emission directions intersect, so that the ordinary light and the extraordinary light can be re-converged into a beam of light later. Among them, the first lens 7 and the second lens 15 can be convex lenses.

The second prism 16 is used to converge the ordinary light and extraordinary light reflected from the surface of the semiconductor material 13 into the second linear polarized light, that is, the light emitted from the second prism 16 is also linearly polarized light. The second linear polarized light is reflected by the second plane mirror 17 and then emitted to the analyzer 19. The analyzer 19 can filter the polarization in other directions to improve the accuracy of the second linear polarized light. Then, the second linear polarized light is incident on the slit. The slit is used to cause interference between the o light and the e light in the second linear polarized light, and then is incident on the photodetector 21. The photodetector 21 is used to convert the received optical signal into an electrical signal so as to subsequently calculate and process the electrical signal.

The photodetector 21 can be connected to a computer 23, which is used to display a defect characterization image of the surface of the semiconductor material 13 according to the electrical signal, that is, the computer 23 can process the electrical signal and convert it into a visible image. The defect characterization image can clearly show defects, cracks, etc. on the surface of the semiconductor material 13.

Specifically, since the surface of the semiconductor material 13 has various defects, after the o-light and the e-light are incident on the material surface, the convexity and concavity of the material surface will cause an optical path difference between the optical paths corresponding to the o-light and the e-light. The image of the semiconductor material 13 becomes enhanced in light and dark contrast due to the interference of the light beams and the change in amplitude. A three-dimensional relief effect can be presented in the defect characterization image, which can make the defect characterization image more clearly show the defects.

In a possible implementation, the defect characterization system may further include a phase-locked amplifier 24 and a chopper 8 connected to each other, the phase-locked amplifier 24 may control the frequency of the chopper 8, and the frequency of the chopper 8 may be connected to a reference signal of the phase-locked amplifier 24 to control the chopper 8. As an example, the frequency of the chopper 8 may be 400 Hz.

As shown in FIG1 , the chopper 8 may be located on the optical path between the first lens 7 and the spectroscopic crystal 11, and is used to adjust the ordinary light and the extraordinary light according to the frequency. That is, the ordinary light and the extraordinary light emitted in parallel may be emitted toward the chopper 8, so that the frequencies of the ordinary light and the extraordinary light are controlled by the chopper 8, that is, the chopper 8 may provide a pulse signal to the system by rotating at a certain frequency.

The phase-locked amplifier 24 can also be connected to the photodetector 21. The electrical signal output by the photodetector 21 is processed by the phase-locked amplifier 24 and then transmitted to the computer 23. The phase-locked amplifier 24 can filter the electrical signal, filter out clutter, reduce noise, improve the accuracy of the obtained electrical signal, and thus improve the accuracy of the image.

In a possible implementation, the defect characterization system may further include a stepper motor controller 25, which is connected to the sample displacement stage 14 and is used to control the movement of the sample displacement stage 14. In other words, the stepper motor controller 25 may control the sample displacement stage 14 to traverse a certain square area so as to measure various areas of the semiconductor material 13 without manually moving the position of the semiconductor material 13, thereby improving the convenience of the measurement operation.

In a possible implementation, the defect characterization system may further include a pinhole filter 3, which is located in the optical path between the supercontinuum laser emitter 1 and the polarizer 5, and is used to purify the laser beam and remove stray light. The pinhole size of the pinhole filter 3 may be 1 micron.

In one possible implementation, the defect characterization system may also include a light source 9 and a CCD detector 22 connected to a computer 23, which is used to calibrate the test position of the semiconductor material 13 before detecting the semiconductor material 13, and to achieve preliminary calibration, so that when using a laser beam to measure defects, the position to be measured can be accurately determined in advance, thereby improving the efficiency and accuracy of defect measurement.

The embodiment of the present application provides a defect characterization system for semiconductor materials, which can make the defect characterization image more clearly show the defects through the difference in optical path difference between ordinary light and extraordinary light caused by defects on the surface of semiconductor materials. Moreover, the laser beam emitted by the supercontinuum laser emitter has a continuous spectrum, and the spectral range can include from ultraviolet light to infrared light, so that various defects in semiconductor materials can be measured, such as deep energy level defects, shallow energy level defects and impurity defects, etc., so that various defects can be more accurately displayed in the defect characterization image, improving the comprehensiveness and accuracy of semiconductor material defect detection.

Referring to FIG. 2 , which is a flow chart of a semiconductor material defect characterization method provided in an embodiment of the present application, the method is applied to a semiconductor material defect characterization system. The method may include the following steps.

S101, controlling the supercontinuum laser emitter 1 to emit a laser beam.

Specifically, the supercontinuum laser emitter 1 may be turned on, and the supercontinuum laser emitter 1 may emit a laser beam having a wider spectrum.

S102 , after passing through the polarizer 5 , the first prism 6 and the first lens 7 , the laser beam emits parallel ordinary light and extraordinary light toward the beam splitting crystal 11 .

S103 , the ordinary light and the extraordinary light pass through the spectroscopic crystal 11 and the microscope 12 , and are incident on the surface of the semiconductor material 13 .

S104, the ordinary light and the extraordinary light reflected back by the semiconductor material 13 pass through the spectroscopic crystal 11, the second lens 15 and the second prism 16 to obtain a second linearly polarized light.

S105 , the second linearly polarized light interferes after passing through the analyzer 19 and the slit, and is incident on the photodetector 21 .

S106, the photodetector 21 converts the received optical signal into an electrical signal.

S107 , the computer 23 displays a defect characterization image of the surface of the semiconductor material 13 according to the electrical signal.

In a possible implementation, before controlling the supercontinuum laser emitter 1 to emit a laser beam, steps S201 to S203 may also be performed.

S201 , the light emitted by the light source 9 passes through the spectroscopic crystal 11 and the microscope 12 , and then is incident on the surface of the semiconductor material 13 .

Specifically, the light source 9 may be turned on, and the light emitted by the light source 9 is reflected by the reflector 10 and incident on the semiconductor material 13, so as to determine the measurement position on the surface of the material.

S202 , the light reflected by the surface of the semiconductor material 13 passes through the spectroscopic crystal 11 , the second lens 15 and the second prism 16 , and is then received by the CCD detector 22 .

S203, the CCD detector 22 transmits the received signal to the computer 23, so that the computer 23 displays the surface image of the semiconductor material 13 and marks the test position of the semiconductor material 13 in the surface image.

In the embodiment of the present application, the light beam emitted by the light source 9 passes through the semi-reflective and semi-transparent lens 10 and the spectroscopic crystal 11, is reflected to the 50× microscope 12 to irradiate the surface of the semiconductor material 13, and is reflected back to the optical path to the CCD detector 22. The CCD detector 22 is connected to the computer 23, and the measurement position is determined in the computer 23. After the measurement position is determined, the semi-reflective and semi-transparent lens 10 and the reflector 18 are moved out of the optical path.

The supercontinuum laser emitter 1 emits a laser beam, which is reflected by the first plane mirror 2 and purified by the pinhole filter 3. The collimated light is modulated by the third lens 4 to the polarizer 5 to generate the first linear polarized light. The first linear polarized light is then decomposed into two polarized lights that vibrate perpendicularly to each other and have a certain phase difference, namely, o light and e light, through the second lens 7. The cross-emitted o light and e light are then adjusted into a pair of parallel lights through the chopper 8 to provide a pulse signal, and then the two parallel lights are reflected to the 50× microscope 12 through the spectroscopic crystal 11, thereby converging to the semi-circular image. The surface of the conductor material 13 will cause a difference in the optical path difference between the two beams of light due to defects on the sample surface. After being reflected by the sample surface, the parallel light is re-converged by the second lens 15, and then re-converged into a beam of light (second linear polarized light) through the Nomarski prism. After being reflected by the second plane mirror 17, it is converged to the photodetector 21 through the convex lens 20 through the analyzer 19. The photodetector 21 receives the light signal and transmits it to the phase-locked amplifier 24. After being processed by the phase-locked amplifier 24, the electrical signal is transmitted to the computer 23 for data analysis, thereby obtaining a defect characterization image.

The test is started by adjusting the phase-locked amplifier 14 to a suitable signal-to-noise ratio and determining the area traversed by the stepper motor controller 25. The data is transmitted to a computer for data analysis through processing by the phase-locked amplifier 14.

The embodiment of the present application provides a defect characterization method for semiconductor materials, which can make the defect characterization image more clearly show the defects through the difference in optical path difference between ordinary light and extraordinary light caused by defects on the surface of the semiconductor material. Moreover, the laser beam emitted by the supercontinuum laser transmitter has a continuous spectrum, and the spectral range can include from ultraviolet light to infrared light, so that various defects in semiconductor materials can be measured, such as deep energy level defects, shallow energy level defects and impurity defects, etc., so that various defects can be more accurately displayed in the defect characterization image, improving the comprehensiveness and accuracy of semiconductor material defect detection.

On the other hand, an embodiment of the present application provides a computer device. Referring to FIG. 3 , which is a structural diagram of a computer device provided by an embodiment of the present application, the computer device includes a processor 310 and a memory 320:

The memory 320 is used to store program codes and transmit the program codes to the processor 310;

The processor 310 is used to execute the method provided in the above embodiment according to the instructions in the program code.

The computer device may include a terminal device or a server, and the aforementioned apparatus may be configured in the computer device.

On the other hand, an embodiment of the present application further provides a storage medium, wherein the storage medium is used to store a computer program, and the computer program is used to execute the method provided by the above embodiment.

A person skilled in the art can understand that all or part of the steps of implementing the above method embodiment can be completed by program instruction hardware, and the above program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above method embodiment; and the above storage medium can be at least one of the following media: read-only memory (English: Read-only Memory, abbreviated: ROM), RAM, magnetic disk or optical disk, etc. Various media that can store program codes.

Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the method embodiment, since it is basically similar to the system embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the system embodiment.

The above is only a preferred implementation of the present application. Although the present application has been disclosed as a preferred embodiment, it is not intended to limit the present application. Any technician familiar with the art can use the above disclosed methods and technical contents to make many possible changes and modifications to the technical solution of the present application without departing from the scope of the technical solution of the present application, or modify it into an equivalent embodiment of equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application still falls within the scope of protection of the technical solution of the present application.

Claims (10)

1. A defect characterization system for semiconductor materials, comprising: A supercontinuum laser emitter for emitting a laser beam; On the optical path between the supercontinuum laser emitter and the spectroscopic crystal, there are a polarizer, a first prism and a first lens arranged in sequence; the polarizer is used to convert the laser beam into a first linear polarized light; the first prism is used to decompose the first linear polarized light into ordinary light and extraordinary light; the first lens is used to make the emission directions of the ordinary light and the extraordinary light parallel; A microscope disposed on an optical path between the spectroscopic crystal and a sample displacement stage, wherein the sample displacement stage is used to place the semiconductor material, and the spectroscopic crystal is used to allow the ordinary light and the extraordinary light to be incident on the microscope so that the microscope can be focused; On the optical path between the spectroscopic crystal and the photodetector, there are a second lens, a second prism, an analyzer and a slit arranged in sequence; the second lens is used to change the emission direction of the ordinary light and the extraordinary light reflected by the surface of the semiconductor material after passing through the spectroscopic crystal; the second prism is used to converge the ordinary light and the extraordinary light reflected by the surface of the semiconductor material into a second linearly polarized light; the slit is used to make the second linearly polarized light interfere and be incident on the photodetector; the photodetector is used to convert the received optical signal into an electrical signal; A computer is used to display a defect representation image of the surface of the semiconductor material according to the electrical signal. 2. The semiconductor material defect characterization system according to claim 1, further comprising: A lock-in amplifier and a chopper connected to each other, wherein the lock-in amplifier is used to control the frequency of the chopper; The chopper is located on an optical path between the first lens and the spectroscopic crystal, and is used for adjusting the ordinary light and the extraordinary light according to the frequency. 3. The semiconductor material defect characterization system according to claim 1, further comprising: The stepper motor controller connected to the sample displacement stage is used to control the movement of the sample displacement stage. 4. The semiconductor material defect characterization system according to claim 1, further comprising: A small-aperture filter located on the optical path between the supercontinuum laser emitter and the polarizer is used to purify the laser beam. 5 . The semiconductor material defect characterization system according to claim 1 , wherein the first prism or the second prism is a Nomarski prism. 6. The semiconductor material defect characterization system according to claim 1, further comprising: The light source and the CCD detector connected to the computer are used to calibrate the test position of the semiconductor material before detecting the semiconductor material. 7. A semiconductor material defect characterization method, characterized in that it is applied to the semiconductor material defect characterization system according to any one of claims 1 to 6, comprising: Controlling the supercontinuum laser emitter to emit the laser beam; After passing through the polarizer, the first prism and the first lens, the laser beam emits the ordinary light and the extraordinary light in parallel to the beam splitting crystal; The ordinary light and the extraordinary light are incident on the surface of the semiconductor material after passing through the spectroscopic crystal and the microscope; The ordinary light and the extraordinary light reflected back by the semiconductor material pass through the light splitting crystal, the second lens and the second prism to obtain the second linearly polarized light; The second linearly polarized light interferes after passing through the analyzer and the slit, and is incident on the photodetector; The photodetector converts the received light signal into an electrical signal; The computer displays a defect representation image of the surface of the semiconductor material based on the electrical signal. 8. The method for characterizing defects in semiconductor materials according to claim 7, characterized in that before controlling the supercontinuum laser emitter to emit the laser beam, the method further comprises: The light emitted by the light source is incident on the surface of the semiconductor material after passing through the spectroscopic crystal and the microscope; The light reflected by the surface of the semiconductor material passes through the spectroscopic crystal, the second lens and the second prism, and is then received by the CCD detector; The CCD detector transmits the received signal to the computer so that the computer displays the surface image of the semiconductor material and marks the test position of the semiconductor material in the surface image. 9. A computer device, characterized in that the computer device comprises a processor and a memory: The memory is used to store program code and transmit the program code to the processor; The processor is configured to execute the method according to any one of claims 7 to 8 according to the instructions in the program code. 10. A computer-readable storage medium, characterized in that the computer-readable storage medium is used to store a computer program, and the computer program is used to execute the method according to any one of claims 7 to 8.