Resistance value measuring device and measuring method

Abstract

The present invention provides a device and method for measuring resistance value. The resistance value measuring method adopts algorithm V n+1 =(V DUT / V SE )˙V n To adjust the bus voltage required for each measurement. Based on the adjustment of the bus voltage, the measured voltage V SE It is also continuously iterated and can quickly converge to the preset condition range, thereby efficiently obtaining the voltage closest to the target voltage V DUT The measured voltage V SE , and calculate the target voltage V accordingly DUT Therefore, the method provided by the present invention can not only significantly reduce the number of measurements, improve measurement efficiency and accuracy, but also avoid damage to the device under test caused by too many measurements.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a resistance value measuring device and a resistance value measuring method. Background Art

[0002] In the process of manufacturing integrated circuits, it is necessary to measure the resistance values ​​of various components. Figure 1 The existing measurement method is based on the Kelvin four-wire measurement circuit. First, the measurement current I is provided to the Hi1 terminal and the Lo1 terminal to form a current loop; then the voltage between the Hi2 terminal and the Lo2 terminal is measured and used as the measurement voltage V of the device under test DUT. SE ; Finally, according to Ohm's law, the resistance value R of the device under test DUT is obtained DUT = V SE / I. However, due to the voltage effect, the resistance of the device under test DUT depends on the measured voltage V SE That is, under the influence of temperature, the resistance of the device under test DUT will change with the measured voltage V SE Therefore, in actual measurement, a fixed target voltage V DUT The resistance value of the device under test (DUT) is adjusted to avoid the influence of voltage effect.

[0003] At present, there are two main measurement schemes. The first is to manually set multiple different bus voltages V F , and applied to the Hi1 terminal and Lo1 terminal one by one, and measured different bus voltages V one by one F The measured voltage V SE . This allows you to select the voltage closest to the target voltage V DUT The measured voltage V SE , and use this to calculate the device under test DUT at the target voltage V DUT However, if Figure 2 As shown, in order to ensure that the target voltage V DUT The measured data, as well as ensuring a certain degree of accuracy, the bus voltage V F The voltage should be subdivided as much as possible, which will not only lead to a large number of measurements, complex data screening, and long time consumption, but also damage the device under test (DUT) due to too many tests. The second method is to use an algorithm to select the voltage closest to the target voltage V DUT The measured voltage V SE . See Figure 1 and Figure 3 , the algorithm formula used in the second measurement scheme is: V n+1 =(V DUT -V SEn )+V n , where Vn The bus voltage V applied for the current test F , V n+1 The bus voltage V applied for the next test F That is, the second measurement scheme is to use the algorithm formula to select each bus voltage V F Compared with the first measurement scheme, it can reduce the amount of data and shorten the time consumption appropriately. Figure 4 As shown in the figure, the voltage difference between Hi2 and Lo2 is applied to the contact resistance R contact Take a part of it, so that V SE Unable to quickly reach the required target voltage V DUT , and the second measurement method still has a large amount of data, takes a long time, and the risk of damage to the device under test DUT is still high.

[0004] Therefore, a new testing algorithm is urgently needed to solve the above technical problems. Summary of the invention

[0005] The object of the present invention is to provide a resistance value measuring device and a measurement method to solve the problem of how to improve the measurement efficiency and accuracy of the resistance under a target voltage.

[0006] In order to solve the above technical problems, the present invention provides a method for measuring resistance value, comprising:

[0007] Step 1: providing a measuring circuit, wherein the measuring circuit is connected with a device under test;

[0008] Step 2: applying a bus voltage to the measurement circuit, and measuring the voltage across the device under test as a measurement voltage;

[0009] Step 3: Determine whether the measured voltage meets the preset conditions, if not, execute step 4; if yes, execute step 5;

[0010] Step 4: Let V n+1 =(V DUT / V SE )˙V n , and V n+1 As the bus voltage in step 2, repeating steps 2 to 3 until step 5 is executed;

[0011] Among them, V n is the current bus voltage, V n+1 is the next bus voltage; V DUT is the target voltage; V SE is the current measured voltage; n is the current measurement number;

[0012] Step 5: Calculate the resistance value of the device under test at the target voltage at least based on the measured voltage.

[0013] Optionally, in the resistance value measurement method, after executing step three and before executing step four, the resistance value measurement method further includes:

[0014] Determine whether the current measured voltage is greater than the barrier voltage. If so, execute step 4. If not, set V n+1 =V b +V n , and V n+1 As the bus voltage in step 2, repeating steps 2 to 3 until step 4 or step 5 is executed;

[0015] Among them, V b is the barrier voltage of the device under test; and when the measured voltage of the device under test is greater than the barrier voltage, the measured voltage and the measured current of the device under test change linearly; when the measured voltage of the device under test is less than or equal to the barrier voltage, the measured voltage and the measured current of the device under test change nonlinearly.

[0016] Optionally, in the resistance value measurement method, the preset condition is:

[0017] V DUT -a˙| V DUT |≤V SE ≤V DUT + a˙| V DUT |;

[0018] Wherein, a is the preset ratio value.

[0019] Optionally, in the resistance value measurement method, a is less than or equal to 1%.

[0020] Optionally, in the resistance value measurement method, in step 2, the current of the device under test is also measured as the measurement current.

[0021] Optionally, in the resistance value measurement method, in step five, the resistance value calculated according to the measurement voltage and the measurement current is used as the resistance value of the device under test at the target voltage.

[0022] Optionally, in the resistance value measurement method, the measurement circuit includes a Kelvin resistance measurement circuit.

[0023] Based on the same inventive concept, the present invention also provides a resistance value measuring device, which is used to perform the resistance value measuring method, and includes: a measuring unit, a judging unit, an adjusting unit and a computing unit;

[0024] The measuring unit comprises a measuring circuit; and the measuring circuit is connected to a device under test;

[0025] The judging unit is used to judge whether the measured voltage meets a preset condition;

[0026] The adjusting unit is used to adjust the bus voltage of the measuring circuit according to the judgment result of the judging unit;

[0027] The computing unit is used to calculate the resistance value of the device under test at the target voltage at least according to the measured voltage.

[0028] Based on the same inventive concept, the present invention also provides a computer program product, including a computer program, characterized in that the computer program can implement the resistance value measurement method when executed by a processor.

[0029] Based on the same inventive concept, the present invention also provides a readable storage medium, characterized in that a computer program is stored on the readable storage medium, and when the computer program is executed by a processor, the steps of the resistance value measurement method are implemented.

[0030] In summary, the present invention provides a device and method for measuring resistance value. The resistance value measuring method adopts algorithm V n+1 =(V DUT / V SE )˙V n To adjust the bus voltage required for each measurement. Based on the adjustment of the bus voltage, the measured voltage V SE It is also continuously iterated and can quickly converge to the preset condition range, thereby efficiently obtaining the voltage closest to the target voltage V DUT The measured voltage V SE , and calculate the target voltage V accordingly DUT Therefore, the method provided by the present invention can not only significantly reduce the number of measurements, improve measurement efficiency and accuracy, but also avoid damage to the device under test caused by too many measurements. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is the Kelvin resistance measurement circuit in the present invention.

[0032] Figure 2 It is a voltage-resistance curve diagram of the measurement process of the first measurement method in the prior art.

[0033] Figure 3 It is a voltage-resistance curve diagram of the measurement process of the second measurement method in the prior art.

[0034] Figure 4 This is a schematic diagram of the contact resistance during the measurement process of the second measurement method in the prior art.

[0035] Figure 5 4 is a flow chart of a method for measuring resistance value in an embodiment of the present invention.

[0036] Figure 6 Schematic diagram of the relationship between the measured voltage and the measured current in the embodiment of the present invention.

[0037] Figure 7 It is a simplified schematic diagram of the relationship between the measured voltage and the measured current in an embodiment of the present invention.

[0038] Figure 8 Schematic diagram of the structure of a resistance value measuring device in an embodiment of the present invention.

[0039] And, in the attached drawings:

[0040] 10- measuring unit; 20- judging unit; 30- adjusting unit; 40- calculating unit;

[0041] V F - Bus voltage; V SE -Measure voltage; V DUT -Target voltage; R W1 -First resistor; R W2 - Second resistor; R W3 - The third resistor; R W4 - Fourth resistor; R contact -contact resistance; DUT-device under test; I-measurement current. DETAILED DESCRIPTION

[0042] In order to make the purpose, advantages and features of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. In addition, the structure shown in the drawings is often a part of the actual structure. In particular, the emphasis of each drawing is different, and sometimes different proportions are used. It should also be understood that, unless otherwise specified or indicated, the terms "first", "second", "third", etc. in the specification are only used to distinguish between the various components, elements, steps, etc. in the specification, and are not used to represent the logical relationship or sequential relationship between the various components, elements, steps, etc.

[0043] See also Figure 1 and Figure 5 , this embodiment provides a method for measuring a resistance value, comprising:

[0044] Step 1 S10: providing a measuring circuit, wherein the measuring circuit is connected to a device under test (DUT);

[0045] Step 2 S20: Apply a bus voltage to the measurement circuit and measure the voltage across the device under test DUT as the measurement voltage V SE ;

[0046] Step 3 S30: Determine the measured voltage V SE Whether the preset conditions are met, if not, execute step 4 S40; if yes, execute step 5 S50;

[0047] Step 4 S40: Set V n+1 =(V DUT / V SE )˙V n , and V n+1 As the bus voltage in step 2 S20, repeating step 2 S20 to step 3 S30 until step 5 S50 is executed;

[0048] Among them, V n is the current bus voltage, V n+1 is the next bus voltage; V DUT is the target voltage; V SE is the current measured voltage; n is the current measurement number;

[0049] Step 5 S50: At least according to the measured voltage V SE , calculate the resistance value of the device under test DUT at the target voltage.

[0050] It can be seen that the resistance value measurement method provided in this embodiment is to use the algorithm V n+1 =(V DUT / V SE )˙V n To adjust the bus voltage required for each measurement. Based on this, the measured voltage V SE Quickly converge to the target voltage V DUT , so as to be able to efficiently and accurately measure the target voltage V DUT The resistance value of the device under test (DUT).

[0051] The following is combined with Figure 1 and Figure 5~Figure 8 , specifically describe the resistance value measurement method provided in this embodiment

[0052] Step 1 S10: Provide a measurement circuit, wherein the measurement circuit is connected to a device under test (DUT).

[0053] Preferably, the measuring circuit is a Kelvin resistance measuring circuit (Kelvin connection). Figure 1 As shown in the figure, the Kelvin resistance measurement circuit uses four wires to measure the voltage V SE Applying the current I to both ends of the device under test DUT can eliminate the influence of wire resistance to the greatest extent, thereby improving the accuracy of the measurement. Figure 1 The first resistor R W1 , the second resistor R W2 , the third resistor R W3 and the fourth resistor R W4 are the cable resistances of the four conductors respectively.

[0054] It should be noted that this embodiment does not limit the specific type of the device under test DUT, which may be a transistor or a polysilicon resistor.

[0055] Step 2 S20: Apply a bus voltage V to the measurement circuit F , and measure the voltage across the device under test DUT as the measurement voltage V SE .

[0056] Preferably, the bus voltage V F Refers to the voltage applied to the Hi1 terminal and the Lo1 terminal in the measurement circuit. Among them, the first applied bus voltage V F It is a preset initial value, which can be selected by engineers based on experience, or the target voltage V DUT As the initial value. And, a voltmeter is connected at both ends of the device under test DUT in the measurement circuit, which is used to directly measure the voltage at both ends of the device under test DUT as the measurement voltage V SE .

[0057] Furthermore, in order to calculate the required resistance value according to Ohm's law, after obtaining the measured voltage V SE In the process, the current flowing through the device under test DUT needs to be measured as the measurement current I. Exemplarily, an excitation current source is used to apply the required bus voltage V to the Hi1 terminal and the Lo1 terminal in the measurement circuit. F , and the current in the measurement circuit can be obtained at the same time. And due to the series connection mode of the measurement circuit, the current I provided by the excitation current source is the measurement current I flowing through the device under test DUT. Alternatively, an excitation voltage source is used to apply a bus voltage V to the Hi1 terminal and the Lo1 terminal in the measurement circuit. F, and using an ammeter to measure the measurement current I flowing through the device under test DUT.

[0058] Step 3 S30: Determine the measured voltage V SE Whether the preset conditions are met, if not, execute step four S40; if yes, execute step five S50.

[0059] It should be noted that the resistance value measurement method provided in this embodiment is intended to quickly obtain the value closest to the target voltage V DUT The measured voltage V SE and the measured voltage V SE The resistance value of the device under test (DUT) obtained under DUT Based on this, the measured voltage V SE It is necessary to determine whether it is the closest to the target voltage V DUT , that is, to determine the measured voltage V SE Whether the preset conditions are met. Preferably, the preset conditions are:

[0060] V DUT -a˙| V DUT |≤V SE ≤V DUT + a˙| V DUT |;

[0061] Wherein, a is a preset ratio value. Preferably, a is less than or equal to 1%. For example, a=1%, and when the measured voltage V SE With the target voltage V DUT The absolute value of the difference is less than or equal to 1% | V DUT |When the measured voltage V SE If the preset condition is met, the measured voltage V SE closest to the target voltage V DUT , the step 5 S50 may be executed to calculate the target voltage V of the device under test DUT. DUT On the contrary, the measured voltage V SE does not meet the preset condition, further adjustment is required through step 4 S40 to make the measured voltage V SE Towards the target voltage V DUT Fast convergence.

[0062] Step 4 S40: Set V n+1 =(V DUT / V SE )˙V n , and V n+1As the bus voltage in step 2 S20, repeat step 2 S20 to step 3 S30 until step 5 S50 is executed; wherein V n is the current bus voltage, V n+1 is the next bus voltage; V DUT is the target voltage; V SE is the current measured voltage; n is the current measurement number.

[0063] It can be understood that this embodiment adopts algorithm V n+1 =(V DUT / V SE )˙V n To adjust the bus voltage V required for each measurement F That is, the current measured voltage V SE As feedback data, it limits the next bus voltage V in proportional form F =V n+1 , so that the measured voltage V SE Quickly converge to the target voltage V DUT , no manual data screening is required, and the number of measurements and the risk of damage to the device under test (DUT) are greatly reduced.

[0064] To further illustrate the technical effect of the resistance value measurement method provided in this embodiment, this embodiment takes the device under test DUT as LDMOS and polysilicon resistor as examples, and performs data verification with the first measurement scheme in the prior art, as follows:

[0065] In one set of tests, the device under test (DUT) is LDMOS and the target voltage V DUT =0.1V, initial bus voltage V F =0.1V. The first measurement scheme in the prior art is used for measurement, and 0.002 V is selected as the bus voltage V F As shown in Table 1, the initial bus voltage V F =0.1 V, measuring current I =0.00116A, we can roughly calculate the resistance value of the device under test DUT R=0.1 / 0.00116=86.2Ω. F When adjusting for the seventh time, measure the voltage V SE =0.10101V, closest to the target voltage V DUT , based on which the resistance value of the device under test DUT can be accurately calculated as R=0.101 / 0.001295=78Ω. Obviously, the difference between the accurate calculation and the rough calculation is large, and the difference ratio is as high as 10.5%. In addition, the first measurement scheme in the prior art requires at least seven measurements.

[0066] Table 1 Test data of the first measurement scheme

[0067]

[0068] Please refer to Table 2. The resistance value measurement method provided in this embodiment only requires two tests. Specifically, assuming a=1%, and the initial bus voltage V F =0.1 V, the measured voltage V SE =0.09017 V. Then determine the measured voltage V SE =0.09017 V does not meet the following preset condition: (0.1 V – 1%˙0.1 V) ≤ V SE ≤(0.1 V + 1%˙0.1 V), then according to the algorithm formula: V n+1 =(V DUT / V SE )˙V n To adjust the bus voltage V F , and measure again. The next bus voltage V can be obtained by calculation F =V n+1 =0.1109 V, based on which the measured voltage V SE =0.0999 V, which meets the preset conditions. Therefore, it can be considered that the measured voltage V SE =0.0999 V is the closest to the target voltage V DUT The voltage value of V SE =0.0999V, the measured current I=1272.7μA, so the resistance value R=V SE / I=0.0999 / 0.0012727=78.2Ω. Compared with the prior art, the method provided in this embodiment can significantly reduce the number of measurements and the risk of damage to the device under test (DUT), and has high measurement accuracy.

[0069] Table 2 Test data of the resistance value measurement method provided in this embodiment

[0070]

[0071] In another set of tests, when the device under test (DUT) is a polysilicon resistor, the target voltage V DUT =0.01V, initial bus voltage V F =0.01 V. Similarly, from Table 3 below, it can be seen that the first measurement scheme requires 40 tests to obtain the voltage closest to the target voltage V DUT The measured voltage V SE Based on this, the resistance value of the device under test DUT R=V SE / I=0.0102 / 0.0023=4.43Ω.

[0072] Table 3 Test data of the first measurement scheme

[0073]

[0074] Please refer to Table 4. The resistance value R=V of the device under test DUT can be obtained by using the resistance value measurement method provided in this embodiment with only three tests. SE / I=0.0101 / 0.0228=4.43Ω, which greatly reduces the number of measurements and the risk of damage to the device under test (DUT), and has high measurement accuracy.

[0075] Table 4 Test data of the resistance value measurement method provided in this embodiment

[0076]

[0077] Based on this, the algorithm V provided in this embodiment n+1 =(V DUT / V SE )˙V n It can make the measured voltage V SE Quickly converge to the target voltage V DUT , so that the target voltage V can be measured efficiently and accurately DUT The resistance value of the device under test (DUT) is measured, which not only improves the measurement efficiency and accuracy, but also reduces the risk of damage to the device under test (DUT).

[0078] For further information, see Figure 6 and Figure 7 In the actual measurement process, when the voltage is small, the current and voltage curves do not change completely linearly. The reason is that the device under test DUT has a barrier voltage V based on its own structure. b , and when measuring the voltage V SE To overcome this barrier voltage V b During the process, the current I and the voltage V are measured. SE It shows a nonlinear change trend, and when the measured voltage V SE Overcoming the barrier voltage V b After that, measure the current I and the voltage V SE In other words, when the measured voltage V SE is greater than the barrier voltage V b When the measured voltage V SE changes linearly with the measured current I; when the measured voltage V SE is less than or equal to the barrier voltage Vb When the resistance of the device under test DUT is infinite relative to the parasitic resistance, the measured voltage V SE It changes nonlinearly with the measured current I. Therefore, to avoid the applied voltage or current being too low, which would cause the measured voltage V SE Falling into the nonlinear change interval, resulting in inaccurate measurement data, after executing the step three S30 and before executing the step four S40, the resistance value measurement method further includes:

[0079] Determine the current measured voltage V SE Is it greater than the barrier voltage V b If yes, execute step 4 S40; if no, set V n+1 =V b +V n , and V n+1 As the bus voltage V in step 2 S20 F , repeat the steps 2 S20 to 3 S30 until the step 4 S40 or the step 5 S50 is executed. It can be understood that when the voltage V is measured SE The measured current I and voltage V SE When the linear change interval is within the range, the algorithm V n+1 =(V DUT / V SE )˙V n To adjust the bus voltage V F When measuring the voltage V SE The measured current I and voltage V SE When the nonlinear change interval is within the range, according to the algorithm V n+1 =V b +V n To adjust the bus voltage V F , and repeat the steps 2 S20 to 3 S30 until the step 4 S40 or the step 5 S50 is executed. That is, Algorithm V n+1 =V b +V n Intended to directly change the barrier voltage V b The voltage applied to the bus is V F On, so that the measured voltage V SE Quickly escape from the nonlinear change range. Figure 7 As shown, in this embodiment, the bus voltage V F The regulation method is used to control the measured voltage V SE Quickly enter the linear change range, that is, directly ignore the measured voltage V SE Non-linear change range to ensure measurement accuracy.

[0080] Step 5 S50: At least according to the measured voltage V SE , calculate the target voltage V of the device under test DUT DUT The resistance value below.

[0081] It can be understood that the measured voltage V obtained by the determination method of step 3 S30 and the iterative method of step 4 S40 is SE is closest to the target voltage V DUT Based on this, the measured voltage V SE The corresponding measurement current I under this condition can be obtained according to Ohm's law. SE The resistance value of the device under test DUT at the target voltage V DUT The resistance value below.

[0082] Based on the same inventive concept, this embodiment also provides a resistance value measuring device for executing the resistance value measuring method. Figure 1 and Figure 8 The resistance value measuring device includes: a measuring unit 10, a judging unit 20, an adjusting unit 30 and an operating unit 40. The measuring unit 10 is a basic hardware circuit of the measuring device and includes a measuring circuit. The measuring circuit is preferably a Kelvin resistance measuring circuit, and a device under test DUT and a voltmeter are connected thereto. The voltmeter is used to measure a measurement voltage V across the device under test DUT. SE Furthermore, the measuring circuit is also connected to a voltage source or a current source to apply a bus voltage V to the Hi1 terminal and the Lo1 terminal. F or the corresponding current. The judging unit 20 is used to execute the judging method in step 3 S30 above; that is, to judge whether the measured voltage V SE If yes, the computing unit 40 is used to calculate the target voltage V of the device under test DUT. DUT if not, the adjustment unit 30 is used to perform the iterative method in step four S40 to quickly find the closest to the target voltage V DUT The measured voltage V SE Therefore, the adjusting unit 30 is used to adjust the bus voltage V of the measuring circuit according to the judgment result of the judging unit 20. F The computing unit 40 is used to measure the voltage V SE and the measured current I, and calculate the target voltage V of the device under test DUT DUT The resistance value below.

[0083] Based on the same inventive concept, this embodiment further provides a computer program product, including a computer program, which can implement the above-mentioned resistance value measurement method when executed by a processor.

[0084] Based on the same inventive concept, this embodiment further provides a readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the steps of the above-mentioned resistance value measurement method are implemented.

[0085] In summary, the resistance value measurement device and method, computer program product and readable storage medium provided in this embodiment are based on the algorithm V n+1 =(V DUT / V SE )˙V n To adjust the bus voltage V required for each measurement F . And based on the bus voltage V F The device under test DUT’s measurement voltage V SE It is also continuously iterated and can quickly converge to the preset condition range, thereby efficiently obtaining the voltage closest to the target voltage V DUT The measured voltage V SE , and calculate the target voltage V accordingly DUT The resistance value of the device under test DUT under test is obtained. Therefore, the method provided in this embodiment can not only significantly reduce the number of measurements, improve measurement efficiency and accuracy, but also reduce the load of the equipment for mass production testing, thereby reducing the equipment cost. At the same time, due to the reduction in the number of measurements, the risk of damage to the device under test DUT caused by the measurement can also be reduced.

[0086] In addition, it should be recognized that although the present invention has been disclosed as a preferred embodiment, the above embodiment is not intended to limit the present invention. For any technician familiar with the art, without departing from the scope of the technical solution of the present invention, the technical content disclosed above can be used to make many possible changes and modifications to the technical solution of the present invention, or modified into equivalent embodiments of equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still belongs to the scope of protection of the technical solution of the present invention.

Claims

1. A method for measuring resistance, characterized in that: include: Step 1: providing a measuring circuit, wherein the measuring circuit is connected to a device under test; Step 2: applying a bus voltage to the measurement circuit, and measuring the voltage across the device under test as a measurement voltage; Step 3: Determine whether the measured voltage meets the preset conditions, if not, execute step 4; If yes, proceed to step 5; Step 4: Let V n+1 =(V DUT / V SE )˙V n , and V n+1 As the bus voltage in step 2, repeating steps 2 to 3 until step 5 is executed; Among them, V n is the current bus voltage, V n+1 is the next bus voltage; V DUT is the target voltage; V SE is the current measured voltage; n is the current measurement number; Step 5: Calculate the resistance value of the device under test at the target voltage at least based on the measured voltage; Wherein, the preset conditions are: V DUT -a˙| V DUT |≤V SE ≤V DUT + a˙| V DUT |; and a is a preset ratio value.

2. The method for measuring resistance value according to claim 1, characterized in that: After executing step 3 and before executing step 4, the resistance value measuring method further includes: Determine whether the current measured voltage is greater than the barrier voltage. If so, execute step 4. If not, set V n+1 =V b +V n , and V n+1 As the bus voltage in step 2, repeating steps 2 to 3 until step 4 or step 5 is executed; Among them, V b is the barrier voltage of the device under test; and when the measured voltage of the device under test is greater than the barrier voltage, the measured voltage and the measured current of the device under test change linearly; when the measured voltage of the device under test is less than or equal to the barrier voltage, the measured voltage and the measured current of the device under test change nonlinearly.

3. The method for measuring resistance value according to claim 1, characterized in that: a is less than or equal to 1%.

4. The method for measuring resistance value according to claim 1, characterized in that: In the step 2, the current of the device under test is also measured as the measurement current.

5. The method for measuring resistance value according to claim 4, characterized in that: In the step five, the resistance value calculated according to the measured voltage and the measured current is used as the resistance value of the device under test at the target voltage.

6. The method for measuring resistance value according to claim 1, characterized in that: The measurement circuit includes a Kelvin resistance measurement circuit.

7. A resistance value measuring device, characterized in that: A method for measuring a resistance value according to any one of claims 1 to 6, comprising: a measuring unit, a judging unit, an adjusting unit and a computing unit; The measuring unit comprises a measuring circuit; and the measuring circuit is connected to a device under test; The judging unit is used to judge whether the measured voltage meets a preset condition; The adjusting unit is used to adjust the bus voltage of the measuring circuit according to the judgment result of the judging unit; The computing unit is used to calculate the resistance value of the device under test at the target voltage at least according to the measured voltage.

8. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the resistance value measuring method as claimed in any one of claims 1 to 6 can be implemented.

9. A readable storage medium, characterized in that: The readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the resistance value measurement method according to any one of claims 1 to 6 are implemented.

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