Four-probe thin-layer sheet resistance testing method and testing device

Abstract

The invention provides a four-probe thin-layer sheet resistance testing method and testing device. The method comprises the following steps: S1, determining the size of a sample and the thickness of an oxide layer; s2, setting a probe test mode and a probe distance according to the sample size; s3, selecting a probe type according to the thickness of the oxide layer; s4, installing a testing device according to the selected probe and the probe distance, testing by the testing device according to the selected detection mode, and converting the collected information into a sheet resistance data set and storing the sheet resistance data set; s5, the server side sends the sample station information to the testing device, and the station information is associated with the corresponding sheet resistance data set and then serves as a testing result to be returned to the server side; and S6, displaying a test result by the server, and judging whether the test is qualified or not according to a set square resistance threshold value. According to the invention, different probe types, quantities and detection modes can be configured according to different sample sizes and sample processes (oxide layer thicknesses), and the detection efficiency and the detection precision are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic square resistance testing, and in particular to a four-probe thin-layer square resistance testing method. The present invention also relates to a four-probe thin-layer square resistance testing device. Background Art

[0002] The cell is the core component of photovoltaic solar cells. The performance of the cell will directly affect the conversion rate and other performance of the battery. Therefore, the performance of the cell needs to be monitored during the solar cell manufacturing process. Among them, the square resistance and resistivity of the cell are important parameters for monitoring the performance of the cell.

[0003] Square resistance is the resistance between opposite sides of a thin layer of conductive material in a square shape, which is related to resistivity. At present, resistivity testing methods are mainly divided into two categories: contact type and non-contact type. Among them, the non-contact eddy current measurement method is more commonly used, but the equipment cost of this method is relatively high. During measurement, the eddy current formed by the coil will generate heat, which will affect the resistivity and lead to inaccurate measurement results. In addition, this method combines the thin layer resistivity of the substrate with the resistivity of the surface layer for measurement, resulting in an unstable measurement structure. The contact type generally adopts the conventional four-probe method. This method is simple and easy to apply, but it is limited by the spacing of the probes. Only one point can be measured each time. When measuring the battery cell, multiple measurements are required point by point, and the measurement efficiency is low. In addition, the battery cell is a thin layer material. When the probe of the conventional four-probe method contacts the sample, the contact force with the sample is unstable, which cannot adapt to the detection of battery cells at different process stages, resulting in unstable test results and affecting the detection accuracy. Based on this, a thin layer square resistance test method and test device based on the four-probe method with fast and accurate measurement is proposed. Summary of the invention

[0004] The present invention aims to provide a four-probe thin layer square resistance testing method to overcome the deficiencies in the prior art.

[0005] In order to solve the above technical problems, the technical solution of the present invention is: a four-probe thin layer square resistance test method, comprising the following steps:

[0006] S1. Determine sample parameters, including sample size and oxide layer thickness;

[0007] S2. Setting a probe test mode and a probe spacing according to the sample size, wherein the probe test mode includes a 5-point test mode and a 9-point test mode;

[0008] S3. Select the probe type according to the thickness of the oxide layer of the sample. The probe type is selected according to the curvature radius of the probe contact end and the probe pressure. The probe pressure is proportional to the elastic force value of the elastic member loaded on the probe. The oxide layer thickness is proportional to the curvature radius and inversely proportional to the probe pressure value.

[0009] S4. Install the test device according to the selected probe and probe spacing, then start the test device. The test device starts testing according to the selected detection mode, and converts the information collected by the probe into a sheet resistance data set through a calculation model and saves it;

[0010] S5. The server sends the station information of the collected sample to the test device. The station information includes the tube number, boat number, machine number, and area number of the sample. The test device associates the station information of the sample with the corresponding sheet resistance data set, and then sends this associated data to the server as the test result;

[0011] S6. The server saves the test result and displays the test result in the form of a chart, and judges whether the sheet resistance test of the test sample is qualified according to the set sheet resistance threshold. The set threshold satisfies the following relational expression: set upper limit value ≥ set threshold ≥ set lower limit value. If the measured sheet resistance value exceeds the set threshold, the test is unqualified and an alarm is issued. If the measured sheet resistance value does not exceed the set threshold range, the test is qualified.

[0012] Further, in the above four-probe sheet resistance test method, in step S2, the 5-point test mode is that 5 probes detect the sheet resistance values of 5 points of the sample. The 5 probes are arranged in an "×" shape and detect the four diagonal points and the center point of the sample respectively.

[0013] Further, in the above four-probe sheet resistance test method, in step S2, the 9-point test mode is that 9 probes detect the sheet resistance values of 9 points of the sample. The 9 probes are arranged in a "field" grid and detect the square perimeter and the center point of the sample respectively.

[0014] Further, in the above four-probe sheet resistance test method, the curvature radius range of the probe is 40 - 500 μm, and the probe pressure range is 50 - 150 g, where g is 9.8 N / kg.

[0015] Further, in the above four-probe sheet resistance test method, the calculation model of the sheet resistance value is:

[0016]

[0017] Combining the above two formulas to obtain the expression of sheet resistance:

[0018]

[0019] Among them, Rs is the sheet resistance, ρ is the resistivity, L is the side length of the square, A is the side area of the square, t is the thin layer thickness, and V 23 / I is the measurement result of the ohmmeter connected to the probe.

[0020] Furthermore, in the above-mentioned four-probe thin layer square resistance test method, the square resistance data set includes the square resistance value, maximum value, minimum value, average value, uniformity, STD / AVG%, and standard deviation of each point tested by the probe, where uniformity = (maximum value - minimum value) / (maximum value + minimum value).

[0021] The present invention also provides a four-probe thin layer square resistance testing device, including a data acquisition module, a data processing module, a communication module, and a control module. The control module controls each module and controls the acquisition mode of the data acquisition module. The data acquisition module collects data according to the set acquisition mode. The data processing module calculates the square resistance data set based on the collected data and saves the square resistance data set. The communication module is used to communicate and connect the data processing module with a server end so that information between the data processing module and the server end is transmitted to each other. The server end is used to collect the work station information of the sample and display the test results.

[0022] Furthermore, in the above-mentioned four-probe thin layer square resistance testing device, the data acquisition module includes probes and an ohmmeter. There are 9 probes installed on the probe board, and each probe is provided with four equidistantly arranged probes. The ohmmeter is connected to the probes to measure the resistance value of the point detected by each probe.

[0023] Furthermore, in the above-mentioned four-probe thin layer square resistance testing device, the 9 probes are arranged in a grid on the probe plate, and the acquisition mode includes a 5-point acquisition mode and a 9-point acquisition mode. When the acquisition mode is the 5-point acquisition mode, the 5 probes located at the four corner points and the center point work to collect data, and when the acquisition mode is the 9-point acquisition mode, the 9 probes collect data at the same time.

[0024] Furthermore, in the above-mentioned four-probe thin layer square resistance testing device, each of the probes is loaded with an elastic member, and the probes are in elastic contact with the sample for detection.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention can configure different probe types, quantities and detection modes according to different sample sizes and sample processes (oxidation layer thickness), thereby ensuring that the contact force with the sample is stable and constant for different samples, thereby improving the detection efficiency and detection accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1It is a schematic diagram of the four-probe thin layer square resistance test device of the present invention;

[0028] Figure 2 It is a probe layout diagram of the four-probe thin layer square resistance test device of the present invention;

[0029] Figure 3 It is a probe layout diagram of a 5-point test mode of a four-probe thin layer square resistance test method of the present invention;

[0030] Figure 4 It is a probe layout diagram of a 9-point test mode of a four-probe thin layer square resistance test method of the present invention;

[0031] Figure 5 It is a schematic diagram of the point current source of the present invention generating concentric spherical equipotential surfaces in a semi-unbounded sample;

[0032] Figure 6 This is a schematic diagram of resistance measurement using the four-probe method at irregular positions of the present invention;

[0033] Figure 7 It is a schematic diagram of the square resistance definition of the present invention;

[0034] Figure 8 This is a schematic diagram of a display page of the server of the present invention;

[0035] In the figure: 1. probe; 2. probe board. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] Example 1

[0038] like Figure 1-2 As shown, a four-probe thin layer square resistance test device includes a data acquisition module, a data processing module, a communication module, and a control module. The control module controls each module and controls the acquisition mode of the data acquisition module. The data acquisition module collects data according to the set acquisition mode. The data processing module calculates the square resistance data set according to the collected data and saves the square resistance data set. The communication module is used to communicate and connect the data processing module with the server end, so that the information between the data processing module and the server end is transmitted to each other. The server end is used to collect the station information of the sample and intuitively display the test results in the form of a chart. The present invention can quickly obtain the square resistance / resistivity distribution information of the sample by communicating with the server end, and can quickly obtain the associated sample station information, which is convenient for later quality management.

[0039] like Figure 2 As shown, the data acquisition module includes a probe 1 and an ohmmeter. The probes 1 are provided with 9 pieces and are installed on a probe board 2. Each probe 1 is provided with four equally spaced probes. The contact surface between the probe and the sample is arc-shaped. The probe spacing is set to 1 mm. The ohmmeter (not shown in the figure) is connected to the probe 1 to measure the resistance value of each probe detection point. The probe board is installed on a translation mechanism. During testing, the translation mechanism drives the probe to approach the sample.

[0040] The 9 probes 1 are arranged in a grid on the probe plate 2. The probe type and layout can be replaced by replacing the probe plate 2, and the spacing between each probe can be adjusted for easy operation. The acquisition mode includes a 5-point acquisition mode and a 9-point acquisition mode. When the acquisition mode is the 5-point acquisition mode, the 5 probes located at the four corner points and the center point work to collect data, and the other four probes do not collect data. When the acquisition mode is the 9-point acquisition mode, the 9 probes collect data at the same time. By setting multiple probes to complete the test of a sample at a time, the test efficiency is improved, and the 5 / 9 multi-point test mode is adopted, the test range is wide and the flexibility is good.

[0041] Each of the probes is loaded with an elastic part, which can be a spring or a shrapnel. The probe and the sample are tested by elastic contact, and the probe pressure is adjusted by adjusting the elastic force value of the elastic part. Since the probe is elastically loaded, when the probe contacts the sample, the probe will be compressed, and the probe will be controlled to produce a constant contact force, thereby ensuring that the test results are stable and accurate. In addition, a wear-resistant part is also set on the outside of the probe, and the wear-resistant part is set close to the elastic part. The wear-resistant part can be made of ruby ​​sheets, which can reduce the wear of the probe and extend the service life of the equipment.

[0042] Example 2

[0043] Based on the four-probe thin layer square resistance test device of Example 1, the present invention also provides a four-probe thin layer square resistance test method, comprising the following steps:

[0044] S1. Determine sample parameters, including sample size and oxide layer thickness;

[0045] S2. Set the probe test mode and probe spacing according to the sample size. The probe test mode includes a 5-point test mode and a 9-point test mode. The sample can be scanned quickly and automatically to obtain the square resistance and resistivity distribution information of different positions of the sample.

[0046] S3. Select the probe type according to the thickness of the oxide layer of the sample. The thickness of the oxide layer is generally determined by the process stage in which the battery cell is located, such as the pre-boron process, the post-boron process, the annealing process, etc. The probe type is selected according to the curvature radius of the probe contact end and the probe pressure. The probe pressure is proportional to the elastic force value of the elastic part loaded on the probe, and the oxide layer thickness is proportional to the curvature radius and inversely proportional to the probe pressure value. The curvature radius of the probe ranges from 40 to 500 μm, and the probe pressure ranges from 50 to 150 g, where g is 9.8 N / kg.

[0047] S4, installing the test device according to the selected probe and probe spacing, and then starting the test device, the test device starts testing according to the selected detection mode, and converts the information collected by the probe into a square resistance data set through a calculation model and saves it;

[0048] S5. The server sends the collected workstation information of the sample to the test device. The workstation information includes the tube number, boat number, machine number, and area number of the sample, and may also include the test time and date. The test device associates the workstation information of the sample with the corresponding square resistance data set, and then sends the associated data as the test result to the server.

[0049] An example of data sent by the test device is: "#boat number@tube number@area number@machine number@mode@square resistance 1@square resistance 2@square resistance 3@square resistance 4@square resistance 5@square resistance 6@square resistance 7@square resistance 8@square resistance 9@maximum value@minimum value@average value@uniformity@STD / AVG%@standard deviation!", where square resistance 1, square resistance 2, square resistance 3, square resistance 4, square resistance 5, square resistance 6, square resistance 7, square resistance 8, square resistance 9 are the square resistance values ​​of 9 points. When the test mode is the 5-point test mode, square resistance 1, square resistance 3, square resistance 5, square resistance 7, square resistance 9 have actual values, and square resistance 2, square resistance 4, square resistance 6, square resistance 8 have 0 points.

[0050] S6. The server saves the test results and displays the above test results in the form of a chart, and determines whether the square resistance test of the test sample is qualified according to the set square resistance threshold. The set threshold satisfies the following relationship: set upper limit value ≥ set threshold value ≥ set lower limit value. If the tested square resistance value exceeds the set threshold value, the test fails and an alarm is issued. If the tested square resistance value does not exceed the set threshold range, the test passes. Since the test results are associated with the workstation information, the location of unqualified samples can be quickly and accurately found and eliminated.

[0051] Among them, in step S2, the 5-point test mode is that 5 probes detect the square resistance values ​​of 5 points of the sample, and the 5 probes are arranged in an "×" shape to detect the four diagonal points and the center point of the sample respectively. Figure 3 shown.

[0052] The 9-point test mode measures the sheet resistance of 9 points on the sample using 9 probes. The 9 probes are arranged in a "field" grid pattern, and they detect the square perimeter and the center point of the sample respectively. As shown in Figure 4 Once the test can complete the test of 9 points, and detect the sheet resistance distribution of the sample. In addition, the number of test points and the position of the points can also be designed and manufactured according to the requirements of customers, supporting the customization of the number of points. When the number of points decreases, the test time is shortened.

[0053] The present invention can configure different probe types, quantities and detection modes according to different sample sizes and sample processes (oxide layer thickness), ensuring stable and constant contact force with the sample for different samples, improving the detection efficiency and detection accuracy. The measurement accuracy of the present invention is <1%, ensuring that the test error of the measurement accuracy between different test instruments of the same model is within the range of ±1%; and the 5-point test mode satisfies the test time ≤ 5 seconds, and the 9-point test mode satisfies the test time ≤ 10 seconds, greatly improving the detection efficiency.

[0054] The design process of the calculation model of the sheet resistance is as follows:

[0055] Among them, the calculation model of the sheet resistance is based on the linear four-probe method. A current loop is formed between the outer probes 1 and 4, and a voltage loop is formed between the inner probes 2 and 3. According to Ohm's law, the resistance value displayed by the ohmmeter connected to the probe is V 23 / I, where V 23 is the voltage value of the voltage loop, and I is the current value of the current loop.

[0056] A sample with infinite thickness is called a semi-infinite sample. A semi-infinite sample is only an ideal state, and actual samples all have finite thickness. In a real sample, when the sample thickness and the distance from the sample edge to the probe are much larger than the probe spacing, the measured sample can be considered a semi-infinite sample. On such a semi-infinite sample, a point current source with an intensity of I is introduced by the probe. If the material is uniform and isotropic, the current distribution is spherically symmetric, and the resulting equipotential surface is a concentric spherical surface. As shown in Figure 5 At a distance r from the center of the point current source, the electric field strength is E = jρ,

[0057] Among them, E is the electric field strength, j is the current density, and ρ is the resistivity. The equipotential surface at a distance r from the point current source is a hemisphere with a radius of r, so its area is 2πr 2 . Therefore, the electric field strength can be expressed as

[0058]

[0059] where I is the current intensity. In the spherical surface, the relationship between the electric field strength and the electric potential at r can be expressed by the following formula

[0060]

[0061] where ψ is the potential at r. Therefore, we can conclude

[0062]

[0063] Taking the electric potential at infinity as zero, we can get the electric potential at r as

[0064]

[0065] The above is the relationship between the potential of a point current source on a semi-unbounded sample and its position r. Schematic diagram of resistance test using irregularly positioned four-probe probes on a semi-unbounded sample, Figure 6 As shown in the figure, points 1 and 4 are the locations of the current input and output probes, respectively, and points 2 and 3 are the locations of the voltage measurement probes. Points 1 and 4 can be regarded as point current sources, so the potentials of points 2 and 3 are

[0066]

[0067] where r 12 , r 24 , r 13 , r 34 are the distances between points 1 and 2, points 2 and 4, points 1 and 3, and points 3 and 4. Therefore, the potential difference between points 2 and 3 is V 23 for

[0068]

[0069] The resistivity expression is derived as

[0070]

[0071] Normally, the four probes are arranged at equal intervals. Assume the probe interval is s, that is, r12 = r34 = s, r13 = r24 = 2s. At this time, the resistivity expression can be simplified to

[0072]

[0073] For thin layer materials, compared with semi-unbounded samples, the difference between thin layer materials is that their equipotential surface distribution is not hemispherical, but cylindrical. It can be understood as cutting off a thin layer of thickness t from the surface of the semi-unbounded sample. At this time, the area of ​​the equipotential surface at a distance r from the point current source is 2πrt. The electric field strength can be expressed as

[0074]

[0075] Similarly, taking the electric potential at infinity as zero, we can get the electric potential at r to be

[0076]

[0077] The potentials between points 2 and 3 are

[0078]

[0079] When the probes are arranged at equal intervals and the interval is s, we get

[0080]

[0081] The resistivity of thin layer material can be expressed as

[0082]

[0083] It can be seen from the above formula 1 that the resistivity test of thin layer materials using the equally spaced four-probe method has nothing to do with the probe spacing s.

[0084] For thin-layer materials, sheet resistance (also called surface resistance) is often used to characterize their conductivity. Sheet resistance is defined as the resistance between opposite sides of a square thin-layer conductive material, such as Figure 7 As shown, according to the definition of resistance:

[0085]

[0086] Substituting the above formula 1 into formula 2, we can get the expression of square resistance:

[0087]

[0088] Among them, Rs is the square resistance, ρ is the resistivity, L is the side length of the square thin layer of conductive material, A is the side area of ​​the square thin layer of conductive material, and t is the thickness of the thin layer. The value of π / ln2 is about 4.532, that is, the coefficient between the sample square resistance and the resistance value displayed by the ohmmeter is 4.532, which makes the measurement convenient and quick.

[0089] In step S4, the square resistance data set includes the square resistance value, maximum value, minimum value, average value, uniformity, STD / AVG%, and standard deviation of each point tested by the probe, where uniformity = (maximum value - minimum value) / (maximum value + minimum value). The calculation formulas of STD (standard deviation) and AGV (average value) are described in detail again in the prior art. The square resistance data set above can intuitively see the square resistance distribution of the battery cell.

[0090] In addition, the square resistance data set may also include repeatability, which is represented by a range value. Specifically, the same sample is measured ten times, and the range value calculation formula is: in the data measured ten times at the same point, the maximum value - minimum value / maximum value + minimum value, the range value of the ten data of each point of the present invention is ≤2%.

[0091] like Figure 8 As shown in the figure, it is the display screen of the server, which displays the measurement end time, 5 o'clock / 9 o'clock test value table, the maximum value, minimum value, average value, uniformity, STD / AVG%, line graph (displaying the actual measured square resistance value and the set threshold value), square resistance test judgment display (OK / NG indicator light), sample station information table, intuitive display diagram of resistance uniformity, test statistics table; the test results can be viewed intuitively and clearly.

[0092] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0093] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A four-probe thin layer square resistance test method, characterized in that: It includes the following steps: S1. Determine the sample parameters, including the sample size and the thickness of the oxide layer; S2. Set the probe test mode and the probe spacing according to the sample size. The probe test mode includes a 5-point test mode and a 9-point test mode; S3. Select the probe type according to the thickness of the sample oxide layer. The probe type is selected according to the curvature radius of the probe contact end and the probe pressure. The probe pressure is proportional to the elastic force value of the elastic member loaded on the probe. The oxide layer thickness is proportional to the curvature radius and inversely proportional to the probe pressure value; S4. Install the test device according to the selected probe and probe spacing, and then start the test device. The test device starts the test according to the selected detection mode, and converts the information collected by the probe into a sheet resistance data set through a calculation model and saves it; S5. The server sends the station information of the collected sample to the test device. The station information includes the tube number, boat number, machine number, and area number of the sample. The test device associates the station information of the sample with the corresponding sheet resistance data set, and then sends this associated data to the server as the test result; S6. The server saves the test result and displays the test result in the form of a chart, and judges whether the sheet resistance test of the test sample is qualified according to the set sheet resistance threshold. The set threshold satisfies the following relational expression: set upper limit value ≥ set threshold ≥ set lower limit value. If the measured sheet resistance value exceeds the set threshold, the test is unqualified and an alarm is issued. If the measured sheet resistance value does not exceed the set threshold range, the test is qualified.

2. The four-probe thin layer square resistance test method according to claim 1, characterized in that: In step S2, the 5-point test mode is that 5 probes detect the sheet resistance values of 5 points of the sample. The 5 probes are arranged in an "×" shape and detect the four diagonal points and the center point of the sample respectively.

3. The four-probe thin layer square resistance test method according to claim 2, characterized in that: In step S2, the 9-point test mode is that 9 probes detect the sheet resistance values of 9 points of the sample. The 9 probes are arranged in a "field" grid and detect the square sides and the center point of the sample respectively.

4. The four-probe thin layer square resistance test method according to claim 1, characterized in that: The curvature radius range of the probe is 40 - 500 μm, and the probe pressure range is 50 - 150 g, where g is 9.8 N / kg.

5. The four-probe thin layer square resistance test method according to claim 1, characterized in that: The calculation model of the sheet resistance value is: Combining the above two formulas to obtain the expression of sheet resistance: Where Rs is the square resistance, ρ is the resistivity, L is the side length of the square, A is the side area of ​​the square, t is the thickness of the thin layer, V 23 / I is the measurement result of the ohmmeter connected to the probe.

6. The four-probe thin layer square resistance test method according to claim 1, characterized in that: The sheet resistance data set includes the sheet resistance values, maximum value, minimum value, average value, uniformity, STD / AVG%, and standard deviation of each point tested by the probe. Among them, uniformity = (maximum value - minimum value) / (maximum value + minimum value).

7. A four-probe thin layer square resistance test device, characterized in that: The test device is applied to the four-probe thin-film sheet resistance test method described in any one of claims 1 to 6, and includes a data acquisition module, a data processing module, a communication module, and a control module. The control module controls each module and the acquisition mode of the data acquisition module. The data acquisition module acquires data according to the set acquisition mode. The data processing module calculates the sheet resistance data set according to the acquired data and saves the sheet resistance data set. The communication module is used for communication connection between the data processing module and the server to enable the mutual transmission of information between the data processing module and the server. The server is used for acquiring the station information of the sample and displaying the test result.

8. The four-probe thin layer square resistance test device according to claim 7, characterized in that: The data acquisition module includes a probe and an ohmmeter. There are 9 probes installed on a probe board. Each probe is provided with four probes arranged equidistantly. The ohmmeter is connected to the probe to measure the resistance value of each point detected by the probe.

9. The four-probe thin layer square resistance test device according to claim 8, characterized in that: The 9 probes are arranged in a grid on the probe plate, and the acquisition modes include a 5-point acquisition mode and a 9-point acquisition mode. When the acquisition mode is the 5-point acquisition mode, the 5 probes located at the four corner points and the center point work to collect data. When the acquisition mode is the 9-point acquisition mode, the 9 probes collect data simultaneously.

10. The four-probe thin layer square resistance test device according to claim 8, characterized in that: Each of the probes is loaded with an elastic member, and the probes are in elastic contact with the sample for detection.

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