Uniformity detection method and device of silicon-based material and computer readable storage medium

Abstract

The invention relates to a uniformity detection method and device for a silicon-based material and a computer readable storage medium. Comprising the following steps: obtaining test luminescence brightness values corresponding to a plurality of test areas of a to-be-detected silicon-based material in a photoluminescence test process, wherein the plurality of test areas cover the whole surface area of the to-be-detected silicon-based material; according to a first standard curve of the silicon-based material to be detected, each test luminance value is converted into a test doping concentration, and the first standard curve represents a corresponding relation between the doping concentration and the luminance value; according to a membership relationship between the plurality of test doping concentrations and a preset doping concentration range, counting the total number of test qualified areas with qualified doping concentrations in the plurality of test areas; and detecting the doping concentration of the to-be-detected silicon-based material according to the total number of the test qualified areas and the total number of the test areas corresponding to the plurality of test areas. By adopting the method, the detection effect of detecting the uniformity of the silicon-based material is improved.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic cell technology, and in particular to a method, device, and computer-readable storage medium for detecting uniformity of silicon-based materials. Background Art

[0002] With the continuous development of science and technology, photovoltaic cells have been widely used in people's lives. As the core component of photovoltaic cells, the electrical properties of silicon-based materials directly determine the photoelectric conversion efficiency of photovoltaic cells. Therefore, it is very necessary to conduct uniformity testing on silicon-based materials. Among them, uniformity refers to the consistency of the physical properties, chemical composition and geometric parameters of each region within the semiconductor material.

[0003] At present, taking the detection of doping concentration uniformity as an example, a four-probe measurement method is usually used to measure the doping concentration of silicon-based materials. However, since the four-probe measurement method is a point-contact measurement, the measured doping concentration is easily affected by factors such as probe spacing, pressure, and measurement point position. At the same time, direct contact between the probe and the surface of the silicon-based material will increase the risk of contamination of the silicon-based material, which in turn makes it easy to have low detection accuracy and low detection efficiency. Therefore, the current detection effect of uniformity detection of silicon-based materials is poor. Summary of the Invention

[0004] Based on this, it is necessary to provide a method, device and computer-readable storage medium for uniformity detection of silicon-based materials to improve the detection effect of uniformity detection of silicon-based materials in order to address the above technical problems.

[0005] In a first aspect, the present application provides a method for detecting uniformity of a silicon-based material, comprising:

[0006] Obtaining test luminous brightness values ​​corresponding to a plurality of test areas of the silicon-based material to be tested during a photoluminescence test, wherein the plurality of test areas cover the entire surface area of ​​the silicon-based material to be tested;

[0007] Converting each test luminescence brightness value into a test doping concentration according to a first standard curve of the silicon-based material to be tested, wherein the first standard curve represents a correspondence between doping concentration and luminescence brightness value, and the first standard curve is constructed based on standard luminescence brightness values ​​and standard doping concentrations of silicon-based material samples;

[0008] Counting the total number of test-qualified regions having qualified doping concentrations in the plurality of test regions according to the affiliation relationship between the plurality of test doping concentrations and the preset doping concentration range;

[0009] The uniformity of the silicon-based material to be tested is tested according to the total number of the test-qualified areas and the total number of test areas corresponding to the multiple test areas.

[0010] In one embodiment, the test area includes a test image area; and obtaining the test luminous brightness values ​​corresponding to each of the multiple test areas during the photoluminescence test of the silicon-based material to be tested includes:

[0011] Collecting a test image corresponding to the entire surface area of ​​the silicon-based material to be tested during a photoluminescence test process, and dividing the test image into a plurality of test image areas;

[0012] Extracting pixel brightness values ​​of a plurality of test pixels located within each test image area;

[0013] The test luminous brightness value of each test image area is determined according to the brightness values ​​of multiple pixels in each test image area.

[0014] In one embodiment, determining the test luminous brightness value of each test image area according to the brightness values ​​of multiple pixels in each test image area includes at least one of the following:

[0015] Taking the pixel brightness value of the designated pixel point within each test image area as the test luminous brightness value;

[0016] According to the brightness values ​​of multiple pixels in each test image area, a brightness characteristic value of the pixels in each test image area is determined, and the brightness characteristic value of the pixels is used as the test luminous brightness value.

[0017] In one embodiment, the preset doping concentration range includes a doping concentration upper limit and a doping concentration lower limit; and counting the total number of test-qualified regions with qualified doping concentrations in the multiple test regions based on the relationship between the multiple test doping concentrations and the preset doping concentration range includes:

[0018] A detection step of randomly selecting a test doping concentration from the multiple test doping concentrations as a target test doping concentration, detecting a first magnitude relationship between the target test doping concentration and the lower limit value of the doping concentration, and detecting a second magnitude relationship between the target test doping concentration and the upper limit value of the doping concentration;

[0019] When it is detected that the target test doping concentration is greater than or equal to the doping concentration lower limit value and less than or equal to the doping concentration upper limit value, updating the preset total number of test qualified areas;

[0020] Return to executing the detection step until the target test doping concentration is selected for all of the multiple test doping concentrations, and use the updated preset total number of test qualified areas as the total number of test qualified areas.

[0021] In one embodiment, the performing of doping concentration detection on the silicon-based material to be detected based on the total number of the qualified test areas and the total number of test areas corresponding to the multiple test areas includes:

[0022] Obtaining the axial doping concentration of the silicon-based material to be tested before slicing;

[0023] determining the total number of the test qualified areas and the test qualified area ratio of the total number of the test areas, and obtaining the radial doping concentration of the silicon-based material to be tested after slicing by fusing the test doping concentrations of the test areas when the test qualified area ratio is greater than a preset qualified area ratio threshold;

[0024] The uniformity of the silicon-based material to be tested is tested according to the axial doping concentration and the radial doping concentration.

[0025] In one embodiment, the uniformity detection of the silicon-based material to be detected according to the axial doping concentration and the radial doping concentration includes:

[0026] Obtaining a first weight corresponding to the axial doping concentration and a second weight corresponding to the radial doping concentration;

[0027] generating a uniformity evaluation parameter according to the axial doping concentration, the radial doping concentration, the first weight, and the second weight;

[0028] According to the magnitude relationship between the uniformity evaluation parameter and a preset uniformity evaluation parameter threshold, uniformity detection is performed on the silicon-based material to be detected.

[0029] In one embodiment, before converting each test luminous brightness value into a test doping concentration according to the first standard curve of the silicon-based material to be tested, the method for testing uniformity of the silicon-based material further includes:

[0030] converting a standard resistivity of at least one predetermined region of the silicon-based material sample into a corresponding standard doping concentration according to a second standard curve of the silicon-based material sample, wherein the second standard curve represents a corresponding relationship between the doping concentration and the resistivity;

[0031] According to the corresponding relationship between the standard doping concentration and the standard luminous brightness value of each preset area of ​​the silicon-based material sample, a first standard curve is obtained by fitting.

[0032] In one embodiment, before fitting the first standard curve based on the correspondence between the standard doping concentration and the standard luminous brightness value of each preset area of ​​the silicon-based material sample, the uniformity detection method of the silicon-based material further includes:

[0033] Extracting a plurality of sampling location points located in respective preset areas of the silicon-based material sample;

[0034] The standard luminous brightness value of each preset area is obtained by fusing the sampled luminous brightness values ​​of the multiple sampling position points.

[0035] In a second aspect, the present application further provides a method and apparatus for detecting uniformity of silicon-based materials, comprising:

[0036] an acquisition module, configured to acquire test luminous brightness values ​​corresponding to respective multiple test areas of the silicon-based material to be tested during a photoluminescence test, wherein the multiple test areas cover the entire surface area of ​​the silicon-based material to be tested;

[0037] a conversion module, configured to convert each test luminescence brightness value into a test doping concentration according to a first standard curve of the silicon-based material to be tested, wherein the first standard curve represents a correspondence between doping concentration and luminescence brightness value, and the first standard curve is constructed based on standard luminescence brightness values ​​and standard doping concentrations of silicon-based material samples;

[0038] a statistical module, configured to count the total number of test qualified regions having qualified doping concentrations in the plurality of test regions according to a membership relationship between the plurality of test doping concentrations and a preset doping concentration range;

[0039] The detection module is used to perform uniformity detection on the silicon-based material to be detected according to the total number of the test-qualified areas and the total number of test areas corresponding to the multiple test areas.

[0040] In a third aspect, the present application further provides a computer device comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the following steps are implemented:

[0041] Obtain test luminous brightness values ​​corresponding to multiple test areas of the silicon-based material to be tested during a photoluminescence test, wherein the multiple test areas cover the entire surface area of ​​the silicon-based material to be tested; convert each test luminous brightness value into a test doping concentration according to a first standard curve of the silicon-based material to be tested, wherein the first standard curve represents the correspondence between the doping concentration and the luminous brightness value, and the first standard curve is constructed according to the standard luminous brightness value and the standard doping concentration of the silicon-based material sample; based on the affiliation between the multiple test doping concentrations and the preset doping concentration range, count the total number of test-qualified areas with qualified doping concentrations in the multiple test areas; and perform uniformity detection on the silicon-based material to be tested based on the total number of test-qualified areas and the total number of test areas corresponding to the multiple test areas.

[0042] In a fourth aspect, the present application further provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the following steps are implemented:

[0043] Obtain test luminous brightness values ​​corresponding to multiple test areas of the silicon-based material to be tested during a photoluminescence test, wherein the multiple test areas cover the entire surface area of ​​the silicon-based material to be tested; convert each test luminous brightness value into a test doping concentration according to a first standard curve of the silicon-based material to be tested, wherein the first standard curve represents the correspondence between the doping concentration and the luminous brightness value, and the first standard curve is constructed according to the standard luminous brightness value and the standard doping concentration of the silicon-based material sample; based on the affiliation between the multiple test doping concentrations and the preset doping concentration range, count the total number of test-qualified areas with qualified doping concentrations in the multiple test areas; and perform uniformity detection on the silicon-based material to be tested based on the total number of test-qualified areas and the total number of test areas corresponding to the multiple test areas.

[0044] In a fifth aspect, the present application further provides a computer program product, comprising a computer program, which, when executed by a processor, implements the following steps:

[0045] Obtain test luminous brightness values ​​corresponding to multiple test areas of the silicon-based material to be tested during a photoluminescence test, wherein the multiple test areas cover the entire surface area of ​​the silicon-based material to be tested; convert each test luminous brightness value into a test doping concentration according to a first standard curve of the silicon-based material to be tested, wherein the first standard curve represents the correspondence between the doping concentration and the luminous brightness value, and the first standard curve is constructed according to the standard luminous brightness value and the standard doping concentration of the silicon-based material sample; based on the affiliation between the multiple test doping concentrations and the preset doping concentration range, count the total number of test-qualified areas with qualified doping concentrations in the multiple test areas; and perform uniformity detection on the silicon-based material to be tested based on the total number of test-qualified areas and the total number of test areas corresponding to the multiple test areas.

[0046] The above-mentioned silicon-based material uniformity detection method, device and computer-readable storage medium first obtain the test luminous brightness values ​​corresponding to each of the multiple test areas obtained by dividing the overall surface area of ​​the silicon-based material to be detected during the photoluminescence test process; then, through a first standard curve that represents the correspondence between the doping concentration and the luminous brightness value, each test luminous brightness value is converted into a test doping concentration, wherein the first standard curve can be constructed based on the standard luminous brightness value and the standard doping concentration of the silicon-based material sample; then, based on the affiliation between the multiple test doping concentrations and the preset doping concentration range, the total number of test-qualified areas in the multiple test areas of the silicon-based material to be detected is counted; finally, based on the total number of test-qualified areas and the total number of test areas, the uniformity of the silicon-based material to be detected is detected; since the multiple test luminous brightness values ​​represent the overall surface area of ​​the silicon-based material to be detected, the total number of test-qualified areas and the total number of test areas is detected; The luminous brightness distribution is obtained, and the first standard curve can realize the linear conversion between the luminous brightness value and the doping concentration, and then the doping concentration distribution of the overall surface area of ​​the silicon-based material to be detected can be quantified, and finally the doping concentration of the silicon-based material to be detected can be quantitatively detected, so that the uniformity detection can be completed by relying on the overall doping concentration distribution of the silicon-based material to be detected, rather than only being able to perform local measurement of the doping concentration of the silicon-based material through the four-probe measurement method. Therefore, the measurement method of the four-probe measurement method is point contact measurement, which overcomes the problem that the measured doping concentration is easily affected by factors such as probe spacing, pressure and measuring point position. At the same time, the direct contact between the probe and the surface of the silicon-based material will increase the contamination risk of the silicon-based material, which makes it easy to have technical defects such as low detection accuracy and low detection efficiency. Therefore, the detection effect of uniformity detection of silicon-based materials is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following briefly introduces the drawings required for use in the embodiments or related technical descriptions. Obviously, the drawings described below are only 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.

[0048] Figure 1 A schematic diagram of a four-probe measurement method for detecting uniformity of silicon-based materials in one embodiment;

[0049] Figure 2 1 is a schematic flow chart of a method for detecting uniformity of silicon-based materials in one embodiment;

[0050] Figure 3 Schematic diagram of a process for detecting uniformity of silicon-based materials according to another embodiment;

[0051] Figure 4 A schematic diagram of the linear relationship between resistivity and luminous brightness value in a method for detecting uniformity of silicon-based materials in another embodiment;

[0052] Figure 5 is a structural block diagram of a device for detecting uniformity of silicon-based materials in one embodiment;

[0053] Figure 6 FIG. 1 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0054] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0055] First of all, it should be understood that the uniformity of silicon-based materials mainly refers to the spatial consistency of parameters such as doping concentration, crystal structure, impurity distribution and geometric dimensions. Once the uniformity is insufficient, on the one hand, it will lead to the discrete electrical properties of silicon-based materials. For example, if the doping concentration in N-type single crystal silicon is locally too high or too low, it will cause the resistivity of N-type single crystal silicon to fluctuate, making the semiconductor device prone to integrated circuit short circuit or failure. On the other hand, it will also lead to the consistency of key processes such as lithography, etching and ion implantation out of control. Therefore, it is very necessary to conduct uniformity detection of silicon-based materials. Taking the detection of doping concentration uniformity as an example, at present, the four-probe measurement method is usually used to achieve it. Figure 1 , Figure 1The figure is a measurement diagram of the four-probe measurement method, in which four probes arranged in a straight line are pressed vertically on the surface of the sample to be measured with a certain pressure, a constant current I is applied to the outer probe No. 1 and the outer probe No. 4, and the potential difference is measured by the inner probe No. 2 and the inner probe No. 3, thereby forming a current loop and a voltage detection loop. Furthermore, according to Ohm's law and the potential distribution theory of a point current source in a semi-infinite uniform medium, the resistivity of the sample can be derived; however, since the measurement method of the four-probe measurement method is point contact measurement, the measured doping concentration is easily affected by factors such as probe spacing, pressure and measurement point position. At the same time, direct contact between the probe and the surface of the silicon-based material will also increase the contamination risk of the silicon-based material, which in turn makes it easy to have low detection accuracy and low detection efficiency. Therefore, from a macroscopic perspective, there is an urgent need for a uniformity detection method for silicon-based materials that improves the detection effect of uniformity detection of silicon-based materials.

[0056] In one embodiment, Figure 2 As shown, a method for detecting uniformity of silicon-based materials is proposed. This embodiment takes the application of this method to a terminal as an example. The terminal includes but is not limited to a personal computer, a laptop computer, a smart phone, and a tablet computer. The terminal is equipped with a uniformity detection device for silicon-based materials. The uniformity detection device for silicon-based materials includes an acquisition module, a conversion module, a statistics module, and a detection module. The acquisition module is used to obtain test luminous brightness values ​​corresponding to multiple test areas of the silicon-based material to be detected during a photoluminescence test, wherein the multiple test areas cover the entire surface area of ​​the silicon-based material to be detected; the conversion module is used to convert each test luminous brightness value into a test doping concentration based on a first standard curve of the silicon-based material to be detected, wherein the first standard curve represents the correspondence between doping concentration and luminous brightness value, and the first standard curve is constructed based on the standard luminous brightness value and standard doping concentration of the silicon-based material sample; the statistics module is used to count the total number of test-qualified areas with qualified doping concentration in the multiple test areas based on the affiliation between the multiple test doping concentrations and a preset doping concentration range; the detection module is used to perform uniformity detection on the silicon-based material to be detected based on the total number of test-qualified areas and the total number of test areas corresponding to the multiple test areas.

[0057] In the process of uniformity detection of the silicon-based material to be detected, the acquisition module, the conversion module, the statistical module and the detection module cooperate with each other. Since the multiple test luminous brightness values ​​represent the luminous brightness distribution of the entire surface area of ​​the silicon-based material to be detected, and the first standard curve can realize the linear conversion between the luminous brightness value and the doping concentration, the doping concentration distribution of the entire surface area of ​​the silicon-based material to be detected can be quantified, and finally the doping concentration of the silicon-based material to be detected can be quantitatively detected, so that the uniformity detection can be completed based on the overall doping concentration distribution of the silicon-based material to be detected, that is, the uniformity of the silicon-based material to be detected can be fed back with a more accurate doping concentration, rather than only being able to perform local measurement of the doping concentration of the silicon-based material to be detected by the four-probe measurement method. Therefore, the detection effect of uniformity detection of silicon-based materials can be improved. It can be understood that this method can also be applied to a server, and can also be applied to a system including a terminal and a server, and is implemented through the interaction between the terminal and the server. In this embodiment, the method includes the following steps 202 to 208. Among them:

[0058] Step 202 : obtaining test luminous brightness values ​​corresponding to a plurality of test areas of the silicon-based material to be tested during a photoluminescence test, wherein the plurality of test areas cover the entire surface area of ​​the silicon-based material to be tested.

[0059] It should be noted that the silicon-based material to be tested is a silicon-based semiconductor material waiting for uniformity characterization. Specifically, it can be used as a substrate material for photovoltaic cells. It forms a PN junction by doping, thereby converting light energy into electrical energy. It can also be used to make memory and logic chips, etc. In some feasible embodiments, the silicon-based material to be tested can be specifically an N-type single crystal silicon wafer, a P-type single crystal silicon wafer or a polycrystalline silicon wafer, etc. Among them, the N-type single crystal silicon wafer is specifically used as a material for high-efficiency batteries such as TOPCon (Tunnel Oxide Passivated Contact), HJT (Heterojunction Technology), and IBC (Interdigitated Back Contact). The P-type single crystal silicon wafer is specifically used as the mainstream material for traditional PERC (Passivated Emitter and Rear Cell). The photoluminescence test process is based on PL (Photol Specifically, by irradiating the material with laser or strong light, the internal electron transition is stimulated. When the electron returns to the ground state, it releases photons (luminescence). Then, by detecting the luminescence intensity and distribution, the defects, doping uniformity and minority carrier lifetime of the silicon-based material are evaluated. It can be understood that through photoluminescence testing, physical quantities related to the luminescence characteristics of silicon-based materials can be obtained.

[0060] It should be noted that the test area representation is a detection unit obtained by dividing the surface of the silicon-based material to be detected based on the test requirements, and the number of test areas is equal to the number of detection units, wherein multiple test areas cover the entire surface area of ​​the silicon-based material to be detected, and multiple test areas can be obtained by uniform division or random division. For example, in one feasible method, assuming that the silicon-based material to be detected is a silicon wafer to be detected, and the size of the silicon wafer to be detected is 120mm×120mm, which is divided into 100 grid areas of 12×12, then each grid area can be represented as a test area, and the photon intensity value detected in each test area during the photoluminescence process can reflect the electron transition activity and material uniformity of the area. For example, assuming that the test luminescence brightness value of a test area A is 5000 counts, and the test luminescence brightness value of other test areas of the silicon-based material to be detected is 4500 counts, then the table It indicates that there are doping concentration differences or defects in the test area A; the test results of the photoluminescence test can be presented in the form of images or numerical values. Specifically, the test results of the photoluminescence test can be a test luminescence brightness value. The test luminescence brightness value is the luminescence intensity per unit area of ​​the silicon-based material under light excitation, and can be expressed as a relative value (such as a grayscale value or a count rate, etc.) or an absolute value. In some feasible embodiments, a fiber optic probe or a point detector can be used to focus on a specific position of each test area of ​​the silicon-based material to be tested, directly output the luminescence intensity value, and use the output luminescence intensity value as the test luminescence brightness value of the area. In other feasible embodiments, a fiber optic probe or a point detector can also be used to focus on a specific position of each test area of ​​the silicon-based material to be tested, directly output the spectral curve, and calculate the test luminescence brightness value of the area based on the spectral curve.

[0061] It should be noted that the tester can manually divide the overall surface area of ​​the silicon-based material to be tested into multiple test areas based on human-computer interaction with the software interface of the terminal, or automatically divide the overall surface area of ​​the silicon-based material to be tested into multiple test areas based on an algorithm; in some feasible embodiments, the coordinate parameters of different test areas can be manually input in the terminal software to obtain multiple test areas; in other feasible embodiments, the test image of the silicon-based material to be tested during the photoluminescence test can be obtained by an area array PL camera, and then the pre-processed test image can be feature segmented, and finally multiple test areas can be automatically generated based on the feature segmentation results; it can be understood that the number and size of the test areas are not specifically limited in this embodiment.

[0062] As an example, step 202 includes: dividing the entire surface area of ​​the silicon-based material to be tested to obtain multiple test areas of the silicon-based material to be tested during the photoluminescence test process, using an optical fiber probe to collect luminous intensity values ​​of the multiple test areas respectively, and using the luminous intensity value of each test area as the corresponding test luminous intensity value.

[0063] Step 204, according to the first standard curve of the silicon-based material to be tested, convert each test luminescence brightness value into a test doping concentration, wherein the first standard curve represents the correspondence between the doping concentration and the luminescence brightness value, and the first standard curve is constructed based on the standard luminescence brightness value and the standard doping concentration of the silicon-based material sample.

[0064] It should be noted that in photoluminescence technology, there is a linear relationship between the test luminescence brightness value and the doping concentration. For details, please refer to the following expression:

[0065]

[0066] in, is the self-excited radiation rate, B is a constant, is the non-equilibrium majority carrier concentration increment, is the background doping concentration; from the above expression, we can see that due to the self-excited radiation rate is the key parameter of the measurable intensity of photoluminescence, and and background doping concentration It is a linear product relationship, and the luminous brightness value can be directly proportional to the background doping concentration. ; Further, the following expression is also disclosed in the relevant literature:

[0067]

[0068] in, is the photoluminescence intensity, B is a constant, is the background doping concentration, is the non-equilibrium minority carrier concentration increment, is the instrument constant; from the above, we can see that the photoluminescence intensity of silicon-based materials It is proportional to the concentration of majority carriers and minority carriers, and ultimately the photoluminescence intensity can be derived Still with background doping concentration It is a linear product relationship; in summary, there is a linear correlation between the test luminescence brightness value and the test doping concentration. The test doping concentration will directly affect the resistivity of the silicon-based material to be tested, and then the distribution of the test luminescence brightness value can be obtained by the distribution of the test doping concentration.

[0069] It should be noted that, since the linear relationship between the luminous brightness value and the doping concentration is objectively present in silicon-based materials, the linear relationship between the luminous brightness value and the doping concentration can be relied upon to realize the conversion of the test luminous brightness value to the test doping concentration. Therefore, a mathematical mapping relationship between the doping concentration and the luminous brightness value can be established in advance to obtain a first standard curve. Specifically, a group of silicon-based materials can be selected as silicon-based material samples, wherein the doping concentration of the silicon-based material samples is known and is within the expected detection range, and then the standard luminous brightness values ​​of each silicon-based material sample are collected respectively. After the doping concentration of each silicon-based material sample is calibrated, the first standard curve is finally constructed by fitting multiple groups of standard luminous brightness values ​​and standard doping concentrations. After the first standard curve and the test luminous brightness values ​​corresponding to each of the multiple test areas have been constructed, the test luminous brightness values ​​of each test area can be converted based on the first standard curve. For example, in one feasible method, it is assumed that the expression of the first standard curve is as follows:

[0070]

[0071] Where C is the doping concentration, L is the luminous brightness value, assuming the test luminous brightness value is 600ADC, the test doping concentration can be converted to ; It can be understood that the silicon-based material sample is a silicon-based material used to construct the first standard curve and has a known doping concentration. The standard luminous brightness value is the measured luminous brightness value of the silicon-based material sample, and the standard doping concentration is the actual doping concentration value of the silicon-based material sample obtained through chemical analysis or physical measurement.

[0072] As an example, step 204 includes: mapping the test luminescence brightness values ​​of the plurality of test areas to corresponding test doping concentrations respectively through a first standard curve of the silicon-based material to be tested.

[0073] Step 206 , counting the total number of test-qualified regions with qualified doping concentrations among the multiple test regions based on the relationship between the multiple test doping concentrations and the preset doping concentration range.

[0074] It should be noted that, since the test luminous brightness values ​​of each test area of ​​the silicon-based material to be tested are known, the uniformity of the silicon-based material to be tested can be tested as a whole, and the qualified doping concentration of each test area can be quantitatively analyzed, thereby providing a basis for quantitatively determining the doping uniformity of the silicon-based material to be tested; the preset doping concentration range represents the qualified doping concentration interval pre-set based on the process requirements, which can be specifically the doping concentration at the target resistivity, wherein the target resistivity is the resistivity value that the silicon-based material to be tested should reach, which is pre-set based on the design requirements of the semiconductor device, and then the doping concentration at the target resistivity is used as the preset doping concentration threshold. For example, assuming that the preset doping concentration range is a specific value ,Will Compare with multiple test doping concentrations one by one, and if they exceed the limit, the test area corresponding to the test doping concentration is judged to be unqualified; it can be understood that, assuming that there are 5 test areas in total, and the doping concentrations of 3 test areas are qualified, the total number of qualified test areas is "3".

[0075] As an example, step 206 includes: determining the number of test doping concentrations less than a preset doping concentration threshold among the multiple test doping concentrations, and using the number of test doping concentrations as the total number of test qualified regions with qualified doping concentrations among the multiple test regions.

[0076] Step 208 : Performing a uniformity test on the silicon-based material to be tested according to the total number of test-qualified areas and the total number of test areas corresponding to the multiple test areas.

[0077] It should be noted that the areas with qualified doping concentration can be defined as effective doping areas. Then, the quantitative detection of the doping uniformity of the silicon-based material to be tested can be achieved by the proportional relationship between the total number of test qualified areas and the total number of test areas. The total number of test qualified areas represents the number of effective doping areas whose doping concentration meets the preset standard. The total number of test areas refers to the total number of all test areas, which can be specifically detected by the following expression:

[0078]

[0079] in, is the effective doping area ratio, is the total number of qualified test areas, is the total number of test areas; it can be understood that, when the silicon-based material to be tested is a silicon wafer to be tested, The uniformity of the radial distribution of the doping concentration can be characterized, while the traditional detection method cannot detect the uniformity of the radial distribution of the doping concentration.

[0080] As an example, step 208 includes: determining the ratio of effective doping areas between the total number of test qualified areas and the total number of test areas corresponding to multiple test areas; when the ratio of effective doping areas is greater than a preset ratio threshold, determining that the doping concentration uniformity of the silicon-based material to be tested is qualified; when the ratio of effective doping areas is less than or equal to the preset ratio threshold, determining that the doping concentration uniformity of the silicon-based material to be tested is unqualified.

[0081] The above-mentioned uniformity detection method of silicon-based materials first obtains the test luminous brightness values ​​corresponding to each of the multiple test areas obtained by dividing the overall surface area of ​​the silicon-based material to be detected during the photoluminescence test process; then, through a first standard curve that characterizes the correspondence between the doping concentration and the luminous brightness value, each test luminous brightness value is converted into a test doping concentration, wherein the first standard curve can be constructed based on the standard luminous brightness value and the standard doping concentration of the silicon-based material sample; then, based on the affiliation between the multiple test doping concentrations and the preset doping concentration range, the total number of test-qualified areas in the multiple test areas of the silicon-based material to be detected is counted; finally, depending on the total number of test-qualified areas and the total number of test areas, the uniformity of the silicon-based material to be detected is detected; since the multiple test luminous brightness values ​​characterize the luminous brightness distribution of the overall surface area of ​​the silicon-based material to be detected The situation, and the first standard curve can realize the linear conversion between the luminous brightness value and the doping concentration, and then the doping concentration distribution of the overall surface area of ​​the silicon-based material to be detected can be quantified, and finally the doping concentration of the silicon-based material to be detected can be quantitatively detected, so that the uniformity detection can be completed based on the overall doping concentration distribution of the silicon-based material to be detected, rather than only being able to perform local measurement of the doping concentration of the silicon-based material through the four-probe measurement method. Therefore, the problem of the four-probe measurement method being a point contact measurement, which causes the measured doping concentration to be easily disturbed by factors such as probe spacing, pressure and measuring point position, is overcome. At the same time, the direct contact between the probe and the surface of the silicon-based material will increase the contamination risk of the silicon-based material, which makes it easy to have technical defects such as low detection accuracy and low detection efficiency. Therefore, the detection effect of uniformity detection of silicon-based materials is improved.

[0082] In one embodiment, referring to Figure 3 The test area includes a test image area; obtaining the test luminous brightness values ​​corresponding to the multiple test areas of the silicon-based material to be tested during the photoluminescence test process, including:

[0083] Step 302 : collecting a test image corresponding to the entire surface area of ​​the silicon-based material to be tested during a photoluminescence test process, and dividing the test image into a plurality of test image areas.

[0084] It should be noted that, since CCD imaging is used to capture dark signals in defective areas, it is possible to accurately identify hidden cracks, black edges, black centers, dislocations, and vortex defects, and thus the image detection technology can completely cover the entire surface of the silicon-based material to be tested, and the entire surface detection can be completed with a single shot; the test image is the photoluminescence image of the silicon-based material to be tested during the photoluminescence test process, and the division method can specifically be a uniform grid division or an area of ​​interest division method, etc., which is not specifically limited in this embodiment.

[0085] As an example, step 302 includes: photographing the entire surface area of ​​the silicon-based material to be tested during the photoluminescence test to obtain a test image, and dividing the test image into multiple test image areas based on a preset division rule.

[0086] Step 304: extracting pixel brightness values ​​of a plurality of test pixels located in each test image area.

[0087] It should be noted that for each test image area, it is composed of multiple test pixels, and the pixel brightness value of each pixel can be used to reflect the local characteristics of the physical position corresponding to the surface of the silicon-based material to be tested. After traversing all the pixels in each test image area, multiple pixel brightness values ​​can be randomly extracted from the pixel brightness matrix corresponding to each test image area as the pixel brightness values ​​of multiple test pixels.

[0088] As an example, step 304 includes: randomly extracting pixel brightness values ​​of a plurality of test pixels in a pixel brightness matrix corresponding to each test image region.

[0089] Step 306 : determining the test luminous brightness value of each test image area according to the brightness values ​​of the multiple pixels in each test image area.

[0090] It should be noted that since the test luminous brightness value of each test image area is fed back by the brightness values ​​of multiple pixels constituting the test image area, the brightness value of each test image area can be determined by the brightness values ​​of multiple pixels. For example, a 100×100 pixel test image area contains the brightness values ​​of 10,000 pixels: [175, 180, 178, ..., 182]. Then, the brightness values ​​of 1,000 pixels are randomly selected from the above 10,000 pixels and fused. The fused brightness value can be used as the test luminous brightness value of the test image area.

[0091] As an example, step 306 includes performing averaging processing on the brightness values ​​of multiple pixels in each test image area, and using the averaging processing results of each test image area as the test luminous brightness value of each test image area.

[0092] In this embodiment, the entire surface area of ​​the silicon-based material to be tested is first photographed during the photoluminescence test to obtain a test image, and then multiple test areas are characterized by images, thereby completely avoiding contact between the probe and the surface of the silicon-based material to be tested. The entire sample surface can be covered by a single image acquisition, thereby simplifying the area division steps and batch calculation process. After extracting the pixel brightness values ​​of multiple test pixels within each test image area, the test luminescence brightness values ​​corresponding to each of the multiple test areas can be efficiently determined based on the multiple pixel brightness values ​​of each test image area. Therefore, the detection effect of uniformity detection of silicon-based materials can be further improved from multiple dimensions such as detection efficiency and detection accuracy.

[0093] In one embodiment, determining the test luminous brightness value of each test image area based on the brightness values ​​of multiple pixels in each test image area includes at least one of the following:

[0094] The pixel brightness value of the designated pixel point in each test image area is used as the test luminous brightness value;

[0095] According to the brightness values ​​of multiple pixels in each test image area, a brightness characteristic value of the pixels in each test image area is determined, and the brightness characteristic value of the pixels is used as the test luminous brightness value.

[0096] It should be noted that for different silicon-based materials to be tested, the requirements for detection accuracy and detection efficiency of doping concentration uniformity detection are different, and different processing methods can be provided to determine the test luminous brightness value of each test image area; designated pixel points represent pixel points at specific positions pre-set based on detection requirements, which can be specifically regional center pixel points, edge pixel points or extreme value pixel points, etc.; in some feasible embodiments, the brightness value of the regional center pixel point is directly used as the test luminous brightness value of the corresponding test image area, thereby simplifying the pixel extraction process within the image area; the pixel brightness feature value represents the index obtained by aggregating the brightness values ​​of all pixels in the test image area, which is used to characterize the overall situation of the luminous characteristics of the test image area, which can be specifically the pixel brightness average, pixel brightness standard deviation or pixel brightness variance, etc., so that the accuracy of the test luminous brightness value can be ensured through further calculation.

[0097] As an example, the pixel brightness value of the central pixel point in each test image area is used as the test luminous brightness value; by fusing multiple pixel brightness values ​​of each test image area, the average pixel brightness value of each test image area is obtained, and the average pixel brightness value of each test image area is used as the test luminous brightness value.

[0098] In this embodiment, different methods for obtaining the test luminous brightness values ​​of the test image area can be set based on the different types of silicon-based materials to be detected. Therefore, the test luminous brightness values ​​of each test image area of ​​the silicon-based material to be detected can be quickly obtained from a macro level through the specified pixel point method, and the test luminous brightness values ​​of each test image area of ​​the silicon-based material to be detected can be accurately captured from a micro level through the characteristic value method. Therefore, while improving the detection effect of uniformity detection of silicon-based materials, the detection flexibility of uniformity detection of silicon-based materials is also improved.

[0099] In one embodiment, the preset doping concentration range includes a doping concentration upper limit and a doping concentration lower limit; and according to the relationship between the plurality of test doping concentrations and the preset doping concentration range, the total number of test qualified regions with qualified doping concentrations in the plurality of test regions is counted, including:

[0100] Detection step: randomly selecting a test doping concentration from multiple test doping concentrations as a target test doping concentration, detecting a first size relationship between the target test doping concentration and a lower limit value of the doping concentration, and detecting a second size relationship between the target test doping concentration and an upper limit value of the doping concentration; when it is detected that the target test doping concentration is greater than or equal to the lower limit value of the doping concentration and less than or equal to the upper limit value of the doping concentration, updating the preset total number of test qualified areas; returning to execute the detection step until the target test doping concentration is selected for all multiple test doping concentrations, and the updated preset total number of test qualified areas is used as the total number of test qualified areas.

[0101] It should be noted that, in silicon-based materials, on the one hand, there may be slight differences between different batches of silicon-based materials, which may lead to fluctuations in the actual concentration of different materials in the same doping process. On the other hand, the doping process of impurity atoms is easily affected by factors such as temperature, time and gas flow, which may also lead to fluctuations in doping concentration. Taking into account the actual application needs, if the detection standard is set to a doping concentration range that includes an upper limit value and a lower limit value of the doping concentration, it can avoid the situation where a large number of qualified doping concentration areas are mistakenly judged as unqualified due to slight process fluctuations. For example, in one feasible method, assuming that the target doping concentration is , and the test doping concentration in a certain area is Although slightly lower than the target value, the electrical properties of the silicon-based material to be tested are still within the qualified range. If it is judged according to a single threshold, it is easy to judge this area as a test failure area.

[0102] It should be noted that the preset doping concentration range can be a pre-set qualified doping concentration range, which includes a doping concentration upper limit value and a doping concentration lower limit value. For each converted test doping concentration, it is necessary to compare the size with the doping concentration upper limit value and the doping concentration lower limit value. Only the test area corresponding to the doping concentration within the range from the doping concentration lower limit value to the doping concentration upper limit value can be regarded as a qualified test area, and then the update of the preset total number of qualified test areas can be triggered.

[0103] As an example, the detection step is: randomly selecting a test doping concentration from multiple test doping concentrations as the target test doping concentration, detecting a first size relationship between the target test doping concentration and the lower limit value of the doping concentration, and detecting a second size relationship between the target test doping concentration and the upper limit value of the doping concentration; when it is detected that the target test doping concentration is greater than or equal to the lower limit value of the doping concentration and less than or equal to the upper limit value of the doping concentration, updating the preset total number of test qualified areas; returning to execute the detection step until the target test doping concentration is selected for all multiple test doping concentrations, and the updated preset total number of test qualified areas is used as the total number of test qualified areas.

[0104] In one practicable manner, when it is detected that the target test doping concentration is less than the doping concentration lower limit, or the test doping concentration is greater than the doping concentration upper limit, the preset total number of test qualified areas is not updated, and the detection step is returned to be executed.

[0105] In this embodiment, by setting a preset doping concentration range including an upper limit value and a lower limit value of the doping concentration, normal process fluctuations can be accommodated, thereby reducing misjudgment of test-qualified areas, and therefore, the detection accuracy of uniformity detection of silicon-based materials can be further improved.

[0106] In one practicable manner, performing doping concentration detection on the silicon-based material to be detected based on the total number of test-qualified areas and the total number of test areas corresponding to the multiple test areas includes:

[0107] Obtain the axial doping concentration of the silicon-based material to be tested before slicing; determine the ratio of the total number of test qualified areas to the total number of test areas, and when the test qualified area ratio is greater than a preset qualified area ratio threshold, obtain the radial doping concentration of the silicon-based material to be tested after slicing by fusing the test doping concentrations of the test areas; perform uniformity detection on the silicon-based material to be tested based on the axial doping concentration and the radial doping concentration.

[0108] It should be noted that the silicon-based material to be tested will present different forms at different process stages of the manufacturing process. The silicon-based material to be tested may be in its original form or in an intermediate form before slicing. For example, the silicon-based material to be tested may be a silicon block or a silicon ingot before slicing, and its specific quantity is not limited. Specifically, the silicon block may be understood as a round single crystal silicon produced by the Czochralski method or the zone melting method. The diameter of the silicon block may be 200~300mm and the length may be 1~2 meters. For another example, the silicon-based material to be tested may be a silicon rod before slicing. Specifically, it is an intermediate form of the silicon block after pre-treatment processes such as cutting and grinding. The silicon-based material to be tested may be called a silicon wafer to be tested after slicing. The silicon wafer to be tested may be understood as a thin slice made of the silicon rod after slicing and polishing, and its thickness is usually ; It can be understood that due to the differences in the morphology and doping characteristics of the same silicon-based material to be tested at different process stages, the dimension of its doping concentration will be adjusted with the process stage. Specifically, in the crystal growth stage of the silicon-based material to be tested, the axial uniformity is mainly considered. In the pretreatment stage of the silicon-based material to be tested, the axial uniformity and longitudinal uniformity are comprehensively considered. In the silicon wafer stage of the silicon-based material to be tested, the radial uniformity is mainly considered.

[0109] It should be noted that in order to achieve the full-process doping concentration uniformity detection of the silicon-based material to be tested from silicon rod to silicon wafer, the doping concentration can be tested separately when the silicon-based material to be tested is in different forms, and the uniformity of the doping concentration can be finally integrated to obtain the uniformity of the doping concentration; the axial doping concentration can be specifically measured by traditional technologies, such as secondary ion mass spectrometry or surface photovoltage; the radial doping concentration is obtained by fusing the doping concentrations of all test areas through a preset algorithm when the proportion of qualified areas meets the standard, and the radial concentration distribution in the silicon wafer plane is obtained; finally, the axial doping concentration and the radial doping concentration are combined to perform uniformity detection on the silicon-based material to be tested. Specifically, in the axial dimension, the concentration fluctuation in the axial direction is analyzed to see whether it is within the allowable range (such as whether the concentration difference between the top and bottom ends of the silicon rod is less than 10%); in the radial dimension, the concentration difference between the center and edge of the silicon wafer cross section is analyzed to see whether it meets the requirements (such as whether the radial concentration gradient is ≤5%). Finally, if the axial and radial concentration fluctuations are both small, the material uniformity is judged to be good; if the fluctuation in one dimension exceeds the limit, the uniformity is judged to be unqualified.

[0110] As an example, a four-probe test method is used to obtain the axial doping concentration of the silicon-based material to be tested before slicing; the ratio of the total number of test qualified areas to the total number of test areas is determined, and when the test qualified area ratio is greater than a preset qualified area ratio threshold, the average test doping concentration of the silicon-based material to be tested after slicing is calculated based on the test doping concentration of each test area, and the average test doping concentration is used as the radial doping concentration; according to a first size relationship between the axial doping concentration and the preset axial doping concentration threshold, and a second size relationship between the radial doping concentration and the preset radial doping concentration threshold, the uniformity of the silicon-based material to be tested is tested.

[0111] In this embodiment, since the axial doping concentration corresponds to axial detection, it reflects the longitudinal uniformity of the silicon-based material to be detected during the growth stage, and the radial doping concentration corresponds to radial detection, it reflects the uniformity of the cross section of the silicon-based material to be detected after slicing. By combining the two, the entire process chain detection of silicon-based materials from rods to sheets can be covered, so that it can be adapted to the doping concentration uniformity detection of silicon-based materials of different forms while analyzing the doping concentration uniformity from multiple dimensions. Therefore, while improving the detection effect of uniformity detection of silicon-based materials, the detection reliability of uniformity detection of silicon-based materials is also improved.

[0112] In one embodiment, uniformity testing is performed on a silicon-based material to be tested based on an axial doping concentration and a radial doping concentration, including:

[0113] Obtain a first weight corresponding to the axial doping concentration and a second weight corresponding to the radial doping concentration; generate a uniformity evaluation parameter based on the axial doping concentration, the radial doping concentration, the first weight and the second weight; and perform uniformity detection on the silicon-based material to be detected based on the size relationship between the uniformity evaluation parameter and a preset uniformity evaluation parameter threshold.

[0114] It should be noted that for different types of silicon-based materials to be tested, the proportion of importance of their axial doping concentration and longitudinal doping concentration in the doping concentration uniformity detection process is different. For example, the silicon rod has higher requirements for axial uniformity, and the first weight corresponding to its axial doping concentration can be set to 70%, while the second weight corresponding to the longitudinal doping concentration after subsequent slicing is 30%. For another example, if the silicon wafer needs to focus on controlling the concentration difference between the edge and the center, the second weight can be set to 0.6, that is, the second weight corresponding to the radial doping concentration accounts for 60%, and the first weight corresponding to the axial doping concentration accounts for 40%; in addition to qualitatively evaluating the doping concentration uniformity of the silicon-based material to be tested, the doping concentration uniformity can also be quantitatively evaluated through uniformity evaluation parameters, where the uniformity evaluation parameters are used to quantify the doping uniformity of the silicon-based material.

[0115] As an example, based on the axial doping concentration, the corresponding first weight is queried, and based on the radial doping concentration, the corresponding second weight is queried; the axial doping concentration, radial doping concentration, first weight, and second weight are input into the calculation expression of the uniformity evaluation parameter to calculate the uniformity evaluation parameter; when the uniformity evaluation parameter is greater than the preset uniformity evaluation parameter threshold, it is determined that the uniformity test of the silicon-based material to be tested is qualified; when the uniformity evaluation parameter is less than or equal to the preset uniformity evaluation parameter threshold, it is determined that the uniformity test of the silicon-based material to be tested is unqualified. In this way, through weight allocation and quantitative evaluation, dynamic and multi-dimensional detection of the doping uniformity of silicon-based materials can be achieved, which not only meets the specific needs of different process stages, but also improves detection efficiency and reliability through standardized processes.

[0116] In one practicable manner, the calculation expression of the uniformity evaluation parameter is as follows:

[0117]

[0118] in, is the uniformity evaluation parameter, is the first weight, is the second weight, is the axial doping concentration, is the radial doping concentration.

[0119] In one embodiment, before converting each test luminous brightness value into a test doping concentration according to a first standard curve of the silicon-based material to be tested, the uniformity detection method of the silicon-based material further includes:

[0120] According to the second standard curve of the silicon-based material sample, the standard resistivity of at least one preset area of ​​the silicon-based material sample is converted into the corresponding standard doping concentration, wherein the second standard curve represents the correspondence between the doping concentration and the resistivity; according to the correspondence between the standard doping concentration and the standard luminous brightness value of each preset area of ​​the silicon-based material sample, the first standard curve is fitted to obtain the first standard curve.

[0121] It should be noted that, in the process of constructing the first standard curve, considering the linear relationship between resistivity and doping concentration and luminous brightness value, the resistivity can be fitted as an intermediate value. Specifically, the standard resistivity and standard doping concentration can be converted by first fitting the second standard curve. The expression of the second standard curve is as follows:

[0122]

[0123] in, is the standard resistivity, is the standard doping concentration, q is the charge, is the electron mobility; as can be seen from the above, since both the charge amount and the electron mobility are known quantities, the conversion between the standard resistivity and the standard doping concentration can be realized; and then based on the standard luminous brightness value, the least squares method is used to fit the first standard curve, where the expression of the first standard curve is as follows:

[0124]

[0125] in, is the standard luminous brightness value, k is the slope, d is the intercept, is the standard doping concentration; based on this, since the slope and intercept are both known quantities, a first standard curve can be obtained for conversion of the test doping concentration and the test luminous brightness value in the subsequent uniformity detection process.

[0126] As an example, a second standard curve for a silicon-based material sample is used to map the standard resistivity of at least one predetermined region of the silicon-based material sample to a corresponding standard doping concentration. Based on the correspondence between the standard doping concentration and the standard luminous brightness value for each predetermined region of the silicon-based material sample, a first standard curve is fitted using the least squares method. In this way, during uniformity testing of the silicon-based material to be tested, after obtaining the test luminous brightness values ​​for multiple test regions, the first standard curve can be used to convert the values ​​to the test doping concentration for each test region. This lays the foundation for improving the effectiveness of uniformity testing of silicon-based materials.

[0127] In one embodiment, before fitting the first standard curve based on the correspondence between the standard doping concentration and the standard luminous brightness value of each preset area of ​​the silicon-based material sample, the uniformity detection method of the silicon-based material further includes:

[0128] Extract multiple sampling position points located in each preset area of ​​the silicon-based material sample; and obtain the standard luminous brightness value of each preset area by fusing the sampled luminous brightness values ​​of the multiple sampling position points.

[0129] It should be noted that the fitting accuracy of the first standard curve directly affects the uniformity detection accuracy of the silicon-based material to be tested. Therefore, when capturing the mapping relationship between the standard doping concentration and the standard luminous brightness value of each preset area of ​​the silicon-based material sample, it is necessary to ensure that the standard luminous brightness value can accurately characterize the luminous characteristics of the corresponding preset area. Therefore, the standard luminous brightness value of each preset area can be obtained by fusion of multiple sampling position points; in some feasible embodiments, assuming that the preset area is the annular area of ​​the silicon wafer to be tested, and the brightness values ​​of the 8 sampling points in the annular area are 240, 242, 245, 243, 241, 244, 243, and 242 respectively, the standard brightness value obtained by weighted average is 242.5.

[0130] As an example, based on the geometric features of each preset area of ​​a silicon-based material sample, sampling points are extracted from each preset area. The sampled luminescence brightness values ​​of multiple sampling points are averaged, and the averaged result is used as the standard luminescence brightness value for each preset area. In this way, through multi-point sampling and fusion, single-point measurement errors caused by factors such as material surface defects and test equipment noise can be reduced, thereby improving the fitting accuracy of the first standard curve. This further lays the foundation for improving the detection accuracy of uniformity testing of silicon-based materials.

[0131] In one practicable manner, referring to Figure 4 , Figure 4 is a schematic diagram of the linear relationship between resistivity and luminous brightness, Figure 4 It can be seen that the result shows that the PL brightness increases with decreasing resistivity. Assuming that the silicon-based material to be tested is a crystal rod, silicon blocks at the head, middle, and tail of a crystal rod are selected as samples, and the resistivity and PL brightness (average brightness) are measured. Then, a second standard curve is fitted, and based on the linear relationship between resistivity and doping concentration, a first standard curve is further fitted. Then, during the uniformity test of the silicon-based material, a test image corresponding to the entire surface area of ​​the silicon-based material to be tested during the photoluminescence test is first collected, and the test image is divided into multiple test image areas; and the pixel brightness values ​​of multiple test pixels located in each test image area are extracted. Then, based on demand, the pixel brightness value of a specified pixel in each test image area is used as the test luminescence brightness value, or, based on the multiple pixel brightness values ​​of each test image area, a pixel brightness characteristic value of each test image area is determined, and the pixel brightness characteristic value is used as the test luminescence brightness value.

[0132] Furthermore, based on the first standard curve that has been constructed, each test luminous brightness value is converted into a test doping concentration, and a detection step is performed: a test doping concentration is randomly selected from multiple test doping concentrations as the target test doping concentration, and a first size relationship between the target test doping concentration and the lower limit value of the doping concentration is detected, as well as a second size relationship between the target test doping concentration and the upper limit value of the doping concentration is detected; when it is detected that the target test doping concentration is greater than or equal to the lower limit value of the doping concentration, and less than or equal to the upper limit value of the doping concentration, the preset total number of test qualified areas is updated; the detection step is returned to be executed until the target test doping concentration is selected for all multiple test doping concentrations, and the updated preset total number of test qualified areas is used as the total number of test qualified areas, and finally, based on the total number of test qualified areas and the total number of test areas corresponding to the multiple test areas, the uniformity detection of the silicon-based material to be detected is completed.

[0133] Since multiple test luminous brightness values ​​represent the luminous brightness distribution of the entire surface area of ​​the silicon-based material to be tested, and the first standard curve can realize the linear conversion between the luminous brightness value and the doping concentration, the doping concentration distribution of the entire surface area of ​​the silicon-based material to be tested can be quantified, and finally the doping concentration of the silicon-based material to be tested can be quantitatively detected, so that the uniformity detection can be completed based on the overall doping concentration distribution of the silicon-based material to be tested, rather than only being able to perform local measurement of the doping concentration of the silicon-based material through the four-probe measurement method. Therefore, the four-probe measurement method is point contact measurement, which overcomes the problem that the measured doping concentration is easily affected by factors such as probe spacing, pressure and measuring point position. At the same time, direct contact between the probe and the surface of the silicon-based material will increase the contamination risk of the silicon-based material, which makes it easy to have technical defects such as low detection accuracy and low detection efficiency. Therefore, the detection effect of uniformity detection of silicon-based materials is improved.

[0134] It should be understood that, although the steps in the flowcharts of the above embodiments are shown in sequence as indicated by the arrows, these steps are not necessarily performed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be performed in other orders. Moreover, at least a portion of the steps in the flowcharts of the above embodiments may include multiple steps or multiple stages, and these steps or stages are not necessarily performed at the same time, but can be performed at different times. The execution order of these steps or stages is not necessarily to be performed in sequence, but can be performed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0135] Based on the same inventive concept, embodiments of the present application also provide a silicon-based material uniformity detection device for implementing the aforementioned silicon-based material uniformity detection method. The solution provided by this device is similar to the solution described in the aforementioned method. Therefore, the specific limitations of one or more silicon-based material uniformity detection device embodiments provided below can be found in the limitations of the silicon-based material uniformity detection method described above and will not be repeated here.

[0136] In an exemplary embodiment, Figure 5 As shown, a uniformity detection device for silicon-based materials is provided, comprising: an acquisition module 501, a conversion module 502, a statistics module 503 and a detection module 504, wherein:

[0137] An acquisition module 501 is configured to acquire test luminous brightness values ​​corresponding to respective test areas of the silicon-based material to be tested during a photoluminescence test, wherein the multiple test areas cover the entire surface area of ​​the silicon-based material to be tested;

[0138] a conversion module 502 for converting each test luminescence brightness value into a test doping concentration according to a first standard curve of the silicon-based material to be tested, wherein the first standard curve represents the correspondence between the doping concentration and the luminescence brightness value, and the first standard curve is constructed based on the standard luminescence brightness value and the standard doping concentration of the silicon-based material sample;

[0139] A statistics module 503 is configured to count the total number of test qualified regions with qualified doping concentrations in the multiple test regions according to the relationship between the multiple test doping concentrations and the preset doping concentration range;

[0140] The detection module 504 is configured to perform uniformity detection on the silicon-based material to be detected based on the total number of test-qualified areas and the total number of test areas corresponding to the multiple test areas.

[0141] In one embodiment, the test area includes a test image area; the acquisition module 501 is further configured to:

[0142] The test image corresponding to the overall surface area of ​​the silicon-based material to be tested during the photoluminescence test is collected, and the test image is divided into multiple test image areas; the pixel brightness values ​​of multiple test pixel points located in each test image area are extracted; and the test luminescence brightness value of each test image area is determined based on the multiple pixel brightness values ​​of each test image area.

[0143] In one embodiment, the acquisition module 501 is further configured to:

[0144] The pixel brightness value of the designated pixel point in each test image area is used as the test luminous brightness value; based on the multiple pixel brightness values ​​of each test image area, the pixel brightness characteristic value of each test image area is determined, and the pixel brightness characteristic value is used as the test luminous brightness value.

[0145] In one embodiment, the preset doping concentration range includes a doping concentration upper limit and a doping concentration lower limit; the statistics module 503 is further configured to:

[0146] Detection step: randomly selecting a test doping concentration from multiple test doping concentrations as a target test doping concentration, detecting a first size relationship between the target test doping concentration and a lower limit value of the doping concentration, and detecting a second size relationship between the target test doping concentration and an upper limit value of the doping concentration; when it is detected that the target test doping concentration is greater than or equal to the lower limit value of the doping concentration and less than or equal to the upper limit value of the doping concentration, updating the preset total number of test qualified areas; returning to execute the detection step until the target test doping concentration is selected for all multiple test doping concentrations, and the updated preset total number of test qualified areas is used as the total number of test qualified areas.

[0147] In one embodiment, the detection module 504 is further configured to:

[0148] Obtain the axial doping concentration of the silicon-based material to be tested before slicing; determine the ratio of the total number of test qualified areas to the total number of test areas, and when the test qualified area ratio is greater than a preset qualified area ratio threshold, obtain the radial doping concentration of the silicon-based material to be tested after slicing by fusing the test doping concentrations of the test areas; perform uniformity detection on the silicon-based material to be tested based on the axial doping concentration and the radial doping concentration.

[0149] In one embodiment, the detection module 504 is further configured to:

[0150] Obtain a first weight corresponding to the axial doping concentration and a second weight corresponding to the radial doping concentration; generate a uniformity evaluation parameter based on the axial doping concentration, the radial doping concentration, the first weight and the second weight; and perform uniformity detection on the silicon-based material to be detected based on the size relationship between the uniformity evaluation parameter and a preset uniformity evaluation parameter threshold.

[0151] In one embodiment, the uniformity detection device for silicon-based materials is further used to:

[0152] According to the second standard curve of the silicon-based material sample, the standard resistivity of at least one preset area of ​​the silicon-based material sample is converted into the corresponding standard doping concentration, wherein the second standard curve represents the correspondence between the doping concentration and the resistivity; according to the correspondence between the standard doping concentration and the standard luminous brightness value of each preset area of ​​the silicon-based material sample, the first standard curve is fitted to obtain the first standard curve.

[0153] In one embodiment, the uniformity detection device for silicon-based materials is further used to:

[0154] Extract multiple sampling position points located in each preset area of ​​the silicon-based material sample; and obtain the standard luminous brightness value of each preset area by fusing the sampled luminous brightness values ​​of the multiple sampling position points.

[0155] Each module in the aforementioned silicon-based material uniformity detection device can be implemented in whole or in part through software, hardware, or a combination thereof. Each module can be embedded in or independent of a processor in a computer device in hardware form, or can be stored in a computer device memory in software form, so that the processor can call and execute the corresponding operations of each module.

[0156] In an exemplary embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as shown in FIG. Figure 6As shown. The computer device includes a processor, a memory, an input / output interface, a communication interface, a display unit and an input device. The processor, the memory and the input / output interface are connected via a system bus, and the communication interface, the display unit and the input device are connected to the system bus via the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be achieved through WIFI, a mobile cellular network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, it realizes a method for detecting the uniformity of silicon-based materials. Those skilled in the art will understand that Figure 6 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0157] In one embodiment, a computer device is further provided, including a memory and a processor. The memory stores a computer program, and the processor implements the steps in the above method embodiments when executing the computer program.

[0158] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above-mentioned method embodiments are implemented.

[0159] In one embodiment, a computer program product is provided, including a computer program, which implements the steps in the above method embodiments when executed by a processor.

[0160] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the above-mentioned embodiments. In particular, any reference to memory, database, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The databases involved in the various embodiments provided herein may include at least one of a relational database and a non-relational database. Non-relational databases may include, but are not limited to, distributed databases based on blockchains. The processors involved in the various embodiments provided herein may be, but are not limited to, general-purpose processors, central processing units (CPUs), graphics processing units (GPUs), digital signal processors (DSPs), programmable logic devices (PLDs), data processing logic devices based on quantum computing, and the like.

[0161] The technical features of the above embodiments can be combined arbitrarily. In order to make the description concise, multiple possible combinations of the technical features in the above embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0162] The above embodiments merely illustrate several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art may make various modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A method for detecting uniformity of silicon-based materials, characterized in that: The method for detecting uniformity of silicon-based materials comprises: Obtaining test luminous brightness values ​​corresponding to a plurality of test areas of the silicon-based material to be tested during a photoluminescence test, wherein the plurality of test areas cover the entire surface area of ​​the silicon-based material to be tested; Converting each test luminescence brightness value into a test doping concentration according to a first standard curve of the silicon-based material to be tested, wherein the first standard curve represents a correspondence between doping concentration and luminescence brightness value, and the first standard curve is constructed based on standard luminescence brightness values ​​and standard doping concentrations of silicon-based material samples; Counting the total number of test-qualified regions having qualified doping concentrations in the plurality of test regions according to the affiliation relationship between the plurality of test doping concentrations and the preset doping concentration range; The uniformity of the silicon-based material to be tested is tested according to the total number of the test-qualified areas and the total number of test areas corresponding to the multiple test areas.

2. The method for detecting uniformity of silicon-based materials according to claim 1, characterized in that: The test area includes a test image area; and obtaining the test luminous brightness values ​​corresponding to the plurality of test areas during the photoluminescence test of the silicon-based material to be tested includes: Collecting a test image corresponding to the entire surface area of ​​the silicon-based material to be tested during a photoluminescence test process, and dividing the test image into a plurality of test image areas; Extracting pixel brightness values ​​of a plurality of test pixels located within each test image area; The test luminous brightness value of each test image area is determined according to the brightness values ​​of multiple pixels in each test image area.

3. The method for detecting uniformity of silicon-based materials according to claim 2, characterized in that: Determining the test luminous brightness value of each test image area according to the brightness values ​​of the multiple pixels in each test image area includes at least one of the following: Taking the pixel brightness value of the designated pixel point within each test image area as the test luminous brightness value; According to the brightness values ​​of multiple pixels in each test image area, a brightness characteristic value of the pixels in each test image area is determined, and the brightness characteristic value of the pixels is used as the test luminous brightness value.

4. The method according to claim 1, characterized in that The preset doping concentration range includes an upper limit value of the doping concentration and a lower limit value of the doping concentration; The counting of the total number of test-qualified regions with qualified doping concentrations in the plurality of test regions according to the affiliation relationship between the plurality of test doping concentrations and the preset doping concentration range comprises: A detection step of randomly selecting a test doping concentration from the multiple test doping concentrations as a target test doping concentration, detecting a first magnitude relationship between the target test doping concentration and the lower limit value of the doping concentration, and detecting a second magnitude relationship between the target test doping concentration and the upper limit value of the doping concentration; When it is detected that the target test doping concentration is greater than or equal to the doping concentration lower limit value and less than or equal to the doping concentration upper limit value, updating the preset total number of test qualified areas; Return to executing the detection step until the target test doping concentration is selected for all of the multiple test doping concentrations, and use the updated preset total number of test qualified areas as the total number of test qualified areas.

5. The method for detecting uniformity of silicon-based materials according to claim 1, characterized in that: The performing doping concentration detection on the silicon-based material to be detected according to the total number of the test-qualified areas and the total number of test areas corresponding to the multiple test areas includes: Obtaining the axial doping concentration of the silicon-based material to be tested before slicing; determining the total number of the test qualified areas and the test qualified area ratio of the total number of the test areas, and obtaining the radial doping concentration of the silicon-based material to be tested after slicing by fusing the test doping concentrations of the test areas when the test qualified area ratio is greater than a preset qualified area ratio threshold; The uniformity of the silicon-based material to be tested is tested according to the axial doping concentration and the radial doping concentration.

6. The method for detecting uniformity of silicon-based materials according to claim 5, characterized in that: The uniformity detection of the silicon-based material to be detected according to the axial doping concentration and the radial doping concentration includes: Obtaining a first weight corresponding to the axial doping concentration and a second weight corresponding to the radial doping concentration; generating a uniformity evaluation parameter according to the axial doping concentration, the radial doping concentration, the first weight, and the second weight; According to the magnitude relationship between the uniformity evaluation parameter and a preset uniformity evaluation parameter threshold, uniformity detection is performed on the silicon-based material to be detected.

7. The method for detecting uniformity of silicon-based materials according to claim 1, characterized in that: Before converting each test luminous brightness value into a test doping concentration according to the first standard curve of the silicon-based material to be tested, the uniformity detection method of the silicon-based material further includes: converting a standard resistivity of at least one predetermined region of the silicon-based material sample into a corresponding standard doping concentration according to a second standard curve of the silicon-based material sample, wherein the second standard curve represents a corresponding relationship between the doping concentration and the resistivity; According to the corresponding relationship between the standard doping concentration and the standard luminous brightness value of each preset area of ​​the silicon-based material sample, a first standard curve is obtained by fitting.

8. The method for detecting uniformity of silicon-based materials according to claim 7, characterized in that: Before fitting the first standard curve according to the correspondence between the standard doping concentration and the standard luminous brightness value of each preset area of ​​the silicon-based material sample, the uniformity detection method of the silicon-based material further includes: Extracting a plurality of sampling location points located in respective preset areas of the silicon-based material sample; The standard luminous brightness value of each preset area is obtained by fusing the sampled luminous brightness values ​​of the multiple sampling position points.

9. A uniformity detection device for silicon-based materials, characterized in that: The uniformity detection device of the silicon-based material comprises: an acquisition module, configured to acquire test luminous brightness values ​​corresponding to respective multiple test areas of the silicon-based material to be tested during a photoluminescence test, wherein the multiple test areas cover the entire surface area of ​​the silicon-based material to be tested; a conversion module, configured to convert each test luminescence brightness value into a test doping concentration according to a first standard curve of the silicon-based material to be tested, wherein the first standard curve represents a correspondence between doping concentration and luminescence brightness value, and the first standard curve is constructed based on standard luminescence brightness values ​​and standard doping concentrations of silicon-based material samples; a statistical module, configured to count the total number of test qualified regions having qualified doping concentrations in the plurality of test regions according to a membership relationship between the plurality of test doping concentrations and a preset doping concentration range; The detection module is used to perform uniformity detection on the silicon-based material to be detected according to the total number of the test-qualified areas and the total number of test areas corresponding to the multiple test areas.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method for detecting uniformity of silicon-based materials according to any one of claims 1 to 8 are implemented.

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