CN114062371B - Silicon carbide wafer life image generation method, system and storage medium - Google Patents
Silicon carbide wafer life image generation method, system and storage medium Download PDFInfo
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Abstract
The invention provides a method, a system and a storage medium for generating the life of a silicon carbide wafer body, which relate to the technical field of silicon carbide, and are characterized in that a PL image of the silicon carbide wafer is obtained by using a photoluminescence imaging instrument, then a functional relation between the life of the silicon carbide wafer body and PL signal intensity is obtained by using a minority carrier continuity equation, a silicon carbide wafer front surface recombination rate equation, a silicon carbide wafer rear surface recombination rate equation and a PL signal intensity equation and calculating a partial differential equation through a computer numerical value, and then a life image of the silicon carbide wafer body is obtained according to the functional relation and the PL image. Compared with a microwave imaging method, the method provided by the invention has the advantages that through a photoluminescence imaging instrument, the speed is higher, meanwhile, the volume life image of the silicon carbide wafer can be directly obtained, the equivalent minority carrier life image is not obtained, and the characterization result is more accurate.
Description
Technical Field
The invention relates to the technical field of silicon carbide, in particular to a method and a system for generating a life image of a silicon carbide wafer surface body and a storage medium.
Background
Minority carrier lifetime of silicon carbide wafers is an important parameter for measuring the quality of silicon carbide wafers, which is usually measured in a non-destructive, non-contact manner by microwave technology.
Recent technological developments have made it possible to obtain equivalent minority carrier lifetime images of silicon carbide wafers using microwave imaging techniques, but this technique has some drawbacks. First, the minority carrier lifetime of a silicon carbide wafer consists of two parts, namely the surface recombination rate of the silicon carbide wafer and the minority carrier lifetime in the bulk of the silicon carbide wafer. The existing microwave imaging technology only can obtain an equivalent minority carrier lifetime image by measuring the photoconductive change value of the whole silicon carbide wafer, and the equivalent minority carrier lifetime, the bulk lifetime and the surface recombination rate have the following relationship: Where τ eff is the equivalent carrier lifetime, τ b is the bulk lifetime, and S is the surface recombination rate, so knowing only the equivalent minority carrier lifetime image is not able to distinguish between the surface recombination rate of silicon carbide and the in vivo minority carrier lifetime of silicon carbide.
Disclosure of Invention
The invention aims to solve the problems mentioned in the background art and provides a method, a system and a storage medium for generating a life image of a silicon carbide wafer.
In order to achieve the above objective, the present invention first provides a method for generating a life image of a silicon carbide wafer, comprising the following steps:
Obtaining a PL image of the silicon carbide wafer;
Establishing a PL signal intensity equation PL count = bΔnΔp, wherein PL count represents PL signal intensity, B represents light absorption reflectance, Δn represents minority carrier concentration, Δp represents majority carrier concentration;
Establishing a carrier continuity equation Where z represents the wafer depth coordinate, t represents time, Δn represents minority carrier concentration, dn represents minority carrier diffusion coefficient, τ b represents silicon carbide wafer bulk lifetime, and G (z, t) represents minority carrier generation rate;
establishing a silicon carbide wafer front surface composite velocity equation Silicon carbide wafer back surface recombination rate equationWherein z=0 represents the front surface of the silicon carbide wafer, z=w represents the back surface of the silicon carbide wafer, W is the depth of the silicon carbide wafer, S 0 represents the front surface recombination rate of the silicon carbide wafer, sw represents the back surface recombination rate of the silicon carbide wafer;
The PL signal intensity equation, the carrier continuity equation, the silicon carbide wafer front surface recombination rate equation and the silicon carbide wafer rear surface recombination rate equation are combined, and a functional relation between the service life of the silicon carbide wafer and the PL signal intensity is obtained through calculation;
And generating a life image of the silicon carbide wafer according to the PL image and the functional relation.
Optionally, the generating the life image of the silicon carbide wafer according to the PL image and the functional relation includes the following steps:
Acquiring a first numerical matrix, wherein the first numerical matrix is a numerical matrix of the PL image;
Converting the first numerical matrix into a second numerical matrix according to the functional relation, wherein the second numerical matrix is a numerical matrix of the life image;
and obtaining a body life image of the silicon carbide wafer according to the second numerical matrix.
Optionally, the obtaining the first numerical matrix further includes the following steps: obtaining an imaging size of the silicon carbide wafer; and converting the PL image into a first numerical matrix according to the imaging size.
Optionally, PL images of the silicon carbide wafer are obtained by a photoluminescence imaging instrument.
The embodiment of the invention also provides a silicon carbide wafer life image generation system, which comprises:
an image acquisition module configured to acquire PL images of silicon carbide wafers;
A first equation block configured to establish a PL signal intensity equation PL count = bΔnΔp, where PL count represents PL signal intensity, B represents light reflection absorption coefficient, Δn represents minority carrier concentration, Δp represents majority carrier concentration;
A second equation module configured to establish a carrier continuity equation Where z represents the wafer depth coordinate, t represents time, Δn represents minority carrier concentration, dn represents minority carrier diffusion coefficient, τ b represents silicon carbide wafer bulk lifetime, and G (z, t) represents minority carrier generation rate;
a third equation module configured to establish a silicon carbide wafer front surface recombination rate equation Silicon carbide wafer back surface recombination rate equationWherein S 0 represents the front surface recombination rate of the silicon carbide wafer and Sw represents the back surface recombination rate of the silicon carbide wafer;
The first calculation module is configured to combine the PL signal intensity equation, the carrier continuity equation, the silicon carbide wafer front surface recombination rate equation and the silicon carbide wafer rear surface recombination rate equation to calculate and obtain a functional relation between the service life of the silicon carbide wafer and the PL signal intensity;
And a second calculation module configured to generate a silicon carbide wafer life image according to the PL image and the functional relation.
Optionally, the second computing module further includes:
The matrix acquisition module is configured to acquire a first numerical matrix, wherein the first numerical matrix is a numerical matrix of the PL image;
the matrix conversion module is configured to convert the first numerical matrix into a second numerical matrix according to the functional relation, wherein the second numerical matrix is a numerical matrix of the life image;
And the image generation module is configured to obtain a body life image of the silicon carbide wafer according to the second numerical matrix.
Optionally, the matrix acquisition module further includes: obtaining an imaging size of the silicon carbide wafer; and converting the PL image into a first numerical matrix according to the imaging size.
The invention has the beneficial effects that:
The invention provides a silicon carbide wafer life image generation method, which comprises the steps of obtaining a PL image of a silicon carbide wafer by using a photoluminescence imaging instrument, obtaining a functional relation between the life of the silicon carbide wafer and PL signal intensity by using a minority carrier continuity equation, a silicon carbide wafer front surface recombination rate equation, a silicon carbide wafer rear surface recombination rate equation and a PL signal intensity equation and calculating a partial differential equation through computer numerical values, and obtaining the life image of the silicon carbide wafer according to the functional relation and the PL image. Compared with a microwave imaging method, the embodiment of the invention has the advantages that through a photoluminescence imaging instrument, the speed is higher, meanwhile, the volume life image of the silicon carbide wafer can be directly obtained, the equivalent minority carrier life image is not obtained, and the characterization result is more accurate.
The features and advantages of the present invention will be described in detail by way of example with reference to the accompanying drawings.
Drawings
FIG. 1 is a block diagram of a method for generating a life image of a silicon carbide wafer according to an embodiment of the present invention;
FIG. 2 is a second flow chart of a method for generating a life image of a silicon carbide wafer according to an embodiment of the present invention;
FIG. 3 is a third flow chart of a method for generating a life image of a silicon carbide wafer according to an embodiment of the present invention;
FIG. 4 is a block diagram of a system for generating a life image of a silicon carbide wafer according to an embodiment of the present invention;
FIG. 5 is a second block diagram of a system for generating a life image of a silicon carbide wafer according to an embodiment of the present invention;
FIG. 6 is a third system diagram of a silicon carbide wafer life image generation system according to an embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to specific examples for the purpose of facilitating understanding to those skilled in the art.
Referring to fig. 1, an embodiment of the present invention provides a method for generating a life image of a silicon carbide wafer, including the following steps:
step S10, acquiring a PL image of a silicon carbide wafer;
Step S20, establishing a PL signal intensity equation PL count=bΔnΔp, where PL count represents PL signal intensity, B represents light reflection absorption coefficient, Δn represents minority carrier concentration, and Δp represents non-equilibrium state hole concentration;
step S30, establishing a carrier continuity equation Where z represents the wafer depth coordinate, t represents time, Δn represents minority carrier concentration, dn represents minority carrier diffusion coefficient, τ b represents silicon carbide wafer bulk lifetime, and G (z, t) represents minority carrier generation rate;
Step S40, establishing a silicon carbide wafer front surface composite velocity equation Silicon carbide wafer back surface recombination rate equation Wherein S 0 represents the front surface recombination rate of the silicon carbide wafer and Sw represents the back surface recombination rate of the silicon carbide wafer;
step S50, the PL signal intensity equation, the carrier continuity equation, the silicon carbide wafer front surface compound rate equation and the silicon carbide wafer rear surface compound rate equation are combined, and the functional relation between the bulk life of the silicon carbide wafer and the PL signal intensity is obtained through calculation;
and step S60, generating a volume life image of the silicon carbide wafer according to the function relation between the volume life of the silicon carbide wafer and the PL signal intensity.
The invention provides a silicon carbide wafer life image generation method, which comprises the steps of obtaining a PL image of a silicon carbide wafer by using a photoluminescence imaging instrument, obtaining a functional relation between the life of the silicon carbide wafer and PL signal intensity by using a minority carrier continuity equation, a silicon carbide wafer front surface recombination rate equation, a silicon carbide wafer rear surface recombination rate equation and a PL signal intensity equation and calculating a partial differential equation through computer numerical values, and obtaining the life image of the silicon carbide wafer according to the functional relation and the PL image. Compared with a microwave imaging method, the embodiment of the invention has higher speed through the photoluminescence imaging instrument, and can be basically completed within a few seconds. Meanwhile, the volume life image of the silicon carbide wafer can be directly obtained, but not the equivalent minority carrier life image, and the characterization result is more accurate.
Furthermore, the PL excitation spectrum of the surface defect of the silicon carbide wafer is obtained by measuring the PL signal, so that the electrical performance parameters of the surface defect of the silicon carbide wafer can be continuously and deeply analyzed, and the method has important scientific value.
Hereinafter, each step of a silicon carbide wafer life image generation method according to an embodiment of the present invention will be described in more detail with reference to the accompanying drawings and examples.
In step S10, a PL image of a silicon carbide wafer is acquired.
Photoluminescence imaging instruments are first used on silicon carbide wafers to generate photoluminescence images, also known as PL images, of the silicon carbide wafers, which can be regarded as a matrix of values characterizing PL signal intensities.
In this embodiment, the PL excitation light exposure time is set to 1 second, the PL excitation light intensity is set to 1 intensity of solar light, then the PL excitation light is irradiated to the silicon carbide wafer, the silicon carbide wafer is caused to generate a PL emission spectrum, and finally an image of the PL emission spectrum intensity is obtained by using a photodetector.
In other embodiments, the method may also perform related steps such as establishing a PL signal intensity equation, establishing a carrier continuity equation, and the like, and then acquire a PL image of the silicon carbide wafer, so long as the step of acquiring the PL image of the silicon carbide wafer is performed before generating a bulk lifetime image of the silicon carbide wafer according to a functional relationship between a bulk lifetime of the silicon carbide wafer and PL signal intensity, the technical effects to be achieved by the present invention may be achieved.
In step S20, a PL signal intensity equation PL count=bΔnΔp is established, where PL count represents PL signal intensity, B represents light reflection absorption coefficient, Δn represents minority carrier concentration, and Δp represents majority carrier concentration.
The working principle of obtaining a photoluminescence image of a silicon carbide wafer by using a photoluminescence imaging instrument is that the silicon carbide wafer is irradiated by laser with certain intensity, the silicon carbide wafer absorbs photons and generates electron hole pairs, the electron hole pairs are in an unbalanced state, the electron hole pairs are directly recombined and emit light with a specific wavelength, and the light with the specific wavelength is collected by the photoluminescence imaging instrument and converted into a numerical matrix according to the intensity of the light, so that an image is finally formed. The PL signal intensity in the PL image characterizes the concentration of electron-hole pairs generated by absorption of photons.
In the present embodiment, the electron concentration in the non-equilibrium state is the minority carrier concentration, and the hole concentration in the non-equilibrium state is the majority carrier concentration.
In step S30, a carrier continuity equation is established
The carrier continuity equation describes the concentration profile of minority carriers in the depth coordinates of silicon carbide generated in the silicon carbide wafer by the laser of a certain intensity.
Where z represents the wafer depth coordinate, t represents time, Δn represents minority carrier concentration, dn represents minority carrier diffusion coefficient, τ b represents silicon carbide wafer bulk lifetime, and G (z, t) represents the rate of minority carrier generation at depth and time of the silicon carbide wafer.
In the carrier continuity equation, the carrierIs the bias of minority carrier concentration function delta n (z, t) with time t and depth coordinate z as independent variables to time t. WhileIs a second order bias of the minority carrier concentration function deltan (z, t) to the depth coordinate z with the time t and the depth coordinate z as independent variables.
In step S40, a silicon carbide wafer front surface recombination rate equation is established Silicon carbide wafer back surface recombination rate equation
Where z=0 represents the front surface of the silicon carbide wafer, z=w represents the back surface of the silicon carbide wafer, W is the depth of the silicon carbide wafer, S 0 represents the front surface recombination rate of the silicon carbide wafer, sw represents the back surface recombination rate of the silicon carbide wafer.
The front surface recombination rate equation of the silicon carbide wafer and the rear surface recombination rate equation of the silicon carbide wafer describe the situation that carriers generated by PL excitation light are recombined at the surface of the silicon carbide wafer, and are boundary conditions for the distribution of the carriers on a depth coordinate.
In step S50, the PL signal intensity equation, the carrier continuity equation, the silicon carbide wafer front surface recombination rate equation, and the silicon carbide wafer rear surface recombination rate equation are combined, and a functional relationship between the bulk lifetime of the silicon carbide wafer and the PL signal intensity is calculated.
The numerical calculation software is used as a tool, and the PL signal intensity equation, the carrier continuity equation, the silicon carbide wafer front surface recombination rate equation and the silicon carbide wafer rear surface recombination rate equation which are input into the numerical calculation software can be calculated, so that the functional relation between the bulk life of the silicon carbide wafer and the PL signal intensity can be finally calculated.
In this embodiment MATLAB is used as numerical calculation software to perform a series of related numerical calculations on the above equation. In other embodiments, other numerical computing software having the same or similar functionality may be employed.
In step S60, a silicon carbide wafer lifetime image is generated from the PL image and the functional relationship.
According to the method for generating the bulk life image of the silicon carbide wafer, provided by the embodiment of the invention, the functional relation between the bulk life and the PL signal intensity is obtained, and then the bulk life image of the silicon carbide wafer can be generated according to the obtained PL image of the silicon carbide wafer.
Referring to fig. 2, generating a silicon carbide wafer lifetime image from the PL image and the functional relationship includes the steps of:
Step S610, a first numerical matrix is obtained, wherein the first numerical matrix is a numerical matrix of the PL image;
Step S620, converting the first numerical matrix into a second numerical matrix according to the functional relation, wherein the second numerical matrix is a numerical matrix of the life image;
And step S630, obtaining a body life image of the silicon carbide wafer according to the second numerical matrix.
In this embodiment, MATLAB is used as a numerical calculation software to obtain a bulk lifetime image of the silicon carbide wafer according to the second numerical matrix. In other embodiments, other numerical computing software having the same or similar functionality may be employed.
In the following, each step in the generation of the life image of the silicon carbide wafer according to the PL image and the functional relationship in the generation of the life image of the silicon carbide wafer according to the embodiment of the present invention will be described in more detail.
In step S610, a first numerical matrix, which is a numerical matrix of the PL image, is acquired.
Because PL images are images formed by irradiating a silicon carbide wafer with laser light of a certain intensity to generate electron-hole pairs, recombining the electron-hole pairs and emitting light of a certain specific wavelength, the light of the specific wavelength is collected by a photoluminescence imaging device and converted into a numerical matrix according to the intensity thereof. Therefore, a corresponding first numerical matrix can be obtained according to the PL image, and the magnitude of each numerical value in the first numerical matrix represents the distribution of PL signal intensity on the silicon carbide wafer.
In one embodiment, the PL image is processed using MATLAB as the numerical computation software to obtain a first numerical matrix in the PL image. In other embodiments, other numerical computing software having the same or similar functionality may be employed.
Referring to fig. 3, in order to obtain a silicon carbide surface velocity image of a specific area or a specific size, step S610 of obtaining a first numerical matrix further includes the steps of:
in step S6110, the imaging dimensions of the silicon carbide wafer are obtained; in one embodiment, the imaging dimension refers to the dimension of a sub-region of the PL image, as well as the dimension of the resulting silicon carbide surface rate image.
In step S6120, the PL image is converted into a first numerical matrix according to the imaging size.
In step S620, the first numerical matrix is converted into a second numerical matrix according to the functional relationship between the bulk lifetime of the silicon carbide wafer and the PL signal intensity, where the second numerical matrix is the numerical matrix of the bulk lifetime image.
In step S630, a bulk lifetime image of the silicon carbide wafer is obtained according to the second numerical matrix.
In conclusion, the method can accurately measure the volume life image of the silicon carbide wafer to a large extent, has the advantages of high imaging speed and specific electrical parameters capable of representing the surface defects of the silicon carbide wafer, and is suitable for representing the quality of the silicon carbide wafer in scientific research and industrial flow line production.
Based on the above-mentioned method for generating the life image of the silicon carbide wafer, the embodiment of the invention also provides a system for generating the life image of the silicon carbide wafer, as shown in fig. 4, the system comprises the following modules:
An image acquisition module 100 is configured to acquire PL images of silicon carbide wafers.
The first equation block 200 is configured to establish a PL signal intensity equation PL count = bΔnΔp, where PL count represents PL signal intensity, B represents light reflection absorption coefficient, Δn represents minority carrier concentration, Δp represents majority carrier concentration.
A second equation module 300 configured to establish a carrier continuity equation Where z represents the wafer depth coordinate, t represents time, Δn represents minority carrier concentration, dn represents minority carrier diffusion coefficient, τ b represents silicon carbide wafer bulk lifetime, and G (z, t) represents minority carrier generation rate.
A third equation module 400 configured to establish a silicon carbide wafer front surface recombination rate equationSilicon carbide wafer back surface recombination rate equationWhere S 0 represents the front surface recombination rate of the silicon carbide wafer and Sw represents the back surface recombination rate of the silicon carbide wafer.
The first calculation module 500 is configured to calculate and obtain a functional relationship between the life of the silicon carbide wafer and the PL signal intensity by combining the PL signal intensity equation, the carrier continuity equation, the front surface recombination rate equation of the silicon carbide wafer, and the rear surface recombination rate equation of the silicon carbide wafer.
A second calculation module 600 is configured to generate a silicon carbide wafer bulk lifetime image from a functional relationship of the bulk lifetime of the silicon carbide wafer with PL signal strength.
Referring to fig. 5, in an embodiment, the second computing module 600 further includes:
A matrix acquisition module 6100 configured to acquire a first numerical matrix that is a numerical matrix of the PL image;
A matrix conversion module 6200 configured to convert the first numerical matrix into a second numerical matrix according to the functional relationship, the second numerical matrix being a numerical matrix of the body life image;
The image generation module 6300 is configured to obtain a bulk lifetime image of the silicon carbide wafer according to the second numerical matrix.
Referring to fig. 6, in an embodiment, the matrix acquisition module 6100 further includes:
A first dimension module 6110 configured to obtain an imaging dimension of the silicon carbide wafer;
a second size module 6120 configured to convert the PL image to a first numerical matrix according to the imaging size.
In summary, the system for generating a life image of a silicon carbide wafer according to the embodiments of the present application may be implemented as a program, and run on a computer device. The memory of the computer device may store various program modules that make up the silicon carbide wafer life image generation system, such as the image acquisition module 100, the first equation module 200, the second equation module 300, the third equation module 400, the first calculation module 500, and the second calculation module 600 shown in fig. 2. The program of each program module causes a processor to execute the steps of a silicon carbide wafer life image generation method of each embodiment of the present application described in the present specification.
The embodiments of the present application also provide a computer readable storage medium having stored thereon a computer program which when executed by a processor implements the steps of a silicon carbide wafer life image generation method of the various embodiments of the present application.
The above embodiments are illustrative of the present invention, and not limiting, and any simple modifications of the present invention fall within the scope of the present invention. The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above examples, and all technical solutions belonging to the concept of the present invention belong to the protection scope of the present invention. It should be noted that modifications and adaptations to the present invention may occur to one skilled in the art without departing from the principles of the present invention and are intended to be within the scope of the present invention.
Claims (8)
1. The method for generating the life image of the silicon carbide wafer is characterized by comprising the following steps of: obtaining a PL image of the silicon carbide wafer;
Establishing a PL signal intensity equation PLcount = bΔnΔp, where PLcount represents PL signal intensity, B represents light absorption reflectance, Δn represents minority carrier concentration, Δp represents majority carrier concentration;
Establishing a carrier continuity equation Where z represents the wafer depth coordinate, t represents time, Δn represents minority carrier concentration, D n represents minority carrier diffusion coefficient, τb represents silicon carbide wafer bulk lifetime, and G (z, t) represents minority carrier generation rate;
establishing a silicon carbide wafer front surface composite velocity equation Silicon carbide wafer back surface recombination rate equationWhere z=0 represents the front surface of the silicon carbide wafer, z=w represents the back surface of the silicon carbide wafer, W represents the depth of the silicon carbide wafer, S0 represents the front surface recombination rate of the silicon carbide wafer, and S w represents the back surface recombination rate of the silicon carbide wafer;
The PL signal intensity equation, the carrier continuity equation, the silicon carbide wafer front surface recombination rate equation and the silicon carbide wafer rear surface recombination rate equation are combined, and a functional relation between the service life of the silicon carbide wafer and the PL signal intensity is obtained through calculation;
generating a silicon carbide wafer bulk lifetime image from the PL image, the functional relationship, wherein an equivalent minority carrier lifetime exists with bulk lifetime and surface recombination rate Is equal to τ eff, is equal to τ b, is equal to the bulk lifetime, and is equal to the surface recombination rate.
2. The method of generating a silicon carbide wafer life image according to claim 1, wherein the generating a silicon carbide wafer life image from the PL image and the functional relationship comprises the steps of:
Acquiring a first numerical matrix, wherein the first numerical matrix is a numerical matrix of the PL image;
Converting the first numerical matrix into a second numerical matrix according to the functional relation, wherein the second numerical matrix is a numerical matrix of the life image;
and obtaining a body life image of the silicon carbide wafer according to the second numerical matrix.
3. The method of generating a silicon carbide wafer life image according to claim 2, wherein the acquiring the first numerical matrix further comprises the steps of:
obtaining an imaging size of the silicon carbide wafer;
and converting the PL image into a first numerical matrix according to the imaging size.
4. The method of generating a life image of a silicon carbide wafer according to claim 1, wherein the PL image of the silicon carbide wafer is obtained by a photoluminescence imaging instrument.
5. A silicon carbide wafer life image generation system, comprising: an image acquisition module configured to acquire PL images of silicon carbide wafers;
A first equation module configured to establish a PL signal intensity equation PLcount = bΔnΔp, where PLcount represents PL signal intensity, B represents light reflection absorption coefficient, Δn represents minority carrier concentration, Δp represents majority carrier concentration;
A second equation module configured to establish a carrier continuity equation Where z represents the wafer depth coordinate, t represents time, Δn represents minority carrier concentration, D n represents minority carrier diffusion coefficient, τb represents silicon carbide wafer bulk lifetime, and G (z, t) represents minority carrier generation rate;
a third equation module configured to establish a silicon carbide wafer front surface recombination rate equation Back surface recombination rate equation for silicon carbide waferWherein S0 represents the front surface recombination rate of the silicon carbide wafer and S w represents the back surface recombination rate of the silicon carbide wafer;
The first calculation module is configured to combine the PL signal intensity equation, the carrier continuity equation, the silicon carbide wafer front surface recombination rate equation and the silicon carbide wafer rear surface recombination rate equation to calculate and obtain a functional relation between the service life of the silicon carbide wafer and the PL signal intensity;
And a second calculation module configured to generate a silicon carbide wafer life image according to the PL image and the functional relation.
6. The silicon carbide wafer life image generation system of claim 5, wherein the second computing module further comprises:
the matrix acquisition module is configured to acquire a first numerical matrix, wherein the first numerical matrix is a numerical matrix of the PL image; the matrix conversion module is configured to convert the first numerical matrix into a second numerical matrix according to the functional relation, wherein the second numerical matrix is a numerical matrix of the life image;
And the image generation module is configured to obtain a body life image of the silicon carbide wafer according to the second numerical matrix.
7. The silicon carbide wafer life image generation system of claim 6, wherein the matrix acquisition module further comprises:
A first dimension module configured to obtain an imaging dimension of a silicon carbide wafer;
a second size module configured to convert the PL image to a first numerical matrix according to the imaging size.
8. A computer-readable storage medium having stored thereon a computer program which, when executed by a processor, implements the silicon carbide wafer life image generation method of any one of claims 1 to 4.
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