A quick evaluation method for stability of silicon piezoresistive pressure sensor

Abstract

The application provides a quick evaluation method for the stability of a silicon piezoresistive pressure sensor. The method first performs an environmental stress screening process of random vibration-temperature and pressure cycle-random vibration, collects data in the environmental stress screening process, and sets relevant criteria, so as to remove faulty sensors on one hand and release the residual stress in the silicon piezoresistive pressure sensor on the other hand, so that the performance index of the sensor tends to be stable. Then, the silicon piezoresistive pressure sensor after the residual stress is released is continuously monitored, and the long-term stability error of the sensor in one year or more years is calculated through the test data. The technical scheme of the application solves the technical problem that the long test time of the sensor stability index in the prior art leads to difficulty in quick evaluation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of pressure sensing, in particular to a rapid evaluation method for stability of a silicon piezoresistive pressure sensor. BACKGROUND

[0002] The silicon piezoresistive pressure sensor is the most mature one among the silicon micro pressure sensors, has the advantages of small volume, easy integration, high sensitivity, strong overload capacity, small process difficulty, low cost, etc., and is widely used in the fields of aerospace, industrial control, consumer electronics, etc. By using micro-machining and integration technology, the silicon piezoresistive pressure sensor has realized miniaturization, integration, intelligentization, serialization, standardization, and development towards high reliability.

[0003] However, the silicon piezoresistive pressure sensor has inherent drift defects, and the performance of the sensor will drift over time during the application process. The specific index performance is the stability of the sensor. The stability of the sensor is an important index for evaluating the performance of the sensor in the subsequent application process and the service life of the product. It is generally evaluated in terms of the relative change amount relative to the full-scale output of the sensor, and the evaluation time unit is year, so it is also called long-term stability. The time consumption of a stability measurement is too long, and there is no suitable acceleration method, so from the practicality and operability, it is necessary to provide a rapid evaluation method for the stability of the silicon piezoresistive pressure sensor. SUMMARY

[0004] The present application provides a rapid evaluation method for the stability of a silicon piezoresistive pressure sensor, which can solve the technical problem of long sensor stability index test time in the prior art, which makes it difficult to realize rapid evaluation.

[0005] According to one aspect of the present application, a rapid evaluation method for the stability of a silicon piezoresistive pressure sensor is provided, the method comprising:

[0006] S1, performing performance test on the silicon piezoresistive pressure sensor to obtain performance test data;

[0007] S2, performing a random vibration on the silicon piezoresistive pressure sensor after the performance test in S1, and performing performance test on the silicon piezoresistive pressure sensor after the random vibration to obtain performance test data;

[0008] S3, judging whether the change amount of the performance test data obtained in S1 and S2 is greater than a first preset threshold value, if yes, turning to S4, and if no, turning to S6;

[0009] S4, repeating S2, judging whether the change amount of the performance test data before and after repeating S2 is greater than the first preset threshold value, if yes, turning to S5, and if no, turning to S6;

[0010] S5, repeating S4, and stopping repeating and rejecting the silicon piezoresistive pressure sensor when the number of repetitions reaches a preset upper limit of the number of vibrations, and judging that the rejected silicon piezoresistive pressure sensor is a faulty sensor;

[0011] S6, adjusting the temperature of the environment where the silicon piezoresistive pressure sensor is located obtained in S3 and / or S4 to make it sequentially cycle at a plurality of preset temperature points, adjusting the pressure of the environment at each preset temperature point to make it cycle a plurality of times to reach a plurality of preset pressure points, and collecting the output data of the silicon piezoresistive pressure sensor corresponding to each pressure point at each temperature point in each round of temperature cycling;

[0012] S7, performing a random vibration on the silicon piezoresistive pressure sensor obtained in S6 after performance testing, and performing performance testing again after the random vibration, and obtaining the performance testing data of the silicon piezoresistive pressure sensor before and after the random vibration;

[0013] S8, judging whether the maximum value of the change amount of the two rounds of output data corresponding to the same pressure point at the same temperature point in each adjacent two rounds of temperature cycling in S6 is greater than a second preset threshold value, if yes, turning to S9, and if no, turning to S11;

[0014] S9, judging whether the change amount of the performance testing data before and after the random vibration in S7 is greater than a third preset threshold value, if yes, turning to S10, and if no, turning to S11;

[0015] S10, repeating S1 to S9, and stopping repeating and rejecting the silicon piezoresistive pressure sensor when the number of repetitions reaches a preset number of repetitions, and judging that the rejected silicon piezoresistive pressure sensor is a faulty sensor;

[0016] S11, performing continuous performance monitoring on the silicon piezoresistive pressure sensor obtained in S8 and / or S9 for a preset time length to obtain a short-term stability error within the preset time length, and calculating a long-term stability error within one year or more years according to the short-term stability error within the preset time length.

[0017] Further, in the random vibration of S2 and S7, the direction perpendicular to the pressure sensitive chip of the silicon piezoresistive pressure sensor is taken as the vibration direction.

[0018] Further, the continuous performance monitoring on the silicon piezoresistive pressure sensor obtained in S8 and / or S9 for a preset time length to obtain a short-term stability error within the preset time length includes: calculating the difference between the maximum value and the minimum value of the output of the silicon piezoresistive pressure sensor at each test point in the performance monitoring process, and taking the maximum one of all the difference values as the short-term stability error within the preset time length.

[0019] Further, the long-term stability error in one year or more years is calculated according to the short-term stability error in the preset time period by the following formula:

[0020]

[0021] In the above formula, δ C represents the long-term stability error, δ D represents the short-term stability error in the preset time period, t represents the preset time period, T represents the calculation time period of the long-term stability error, and V represents the full-scale output of the silicon piezoresistive pressure sensor.

[0022] Further, the preset time period is not less than one week, and the number of continuous performance monitoring in the preset time period is not less than 3 times.

[0023] Further, the determination in S6 whether the maximum value of the change amount of the two rounds of output data corresponding to the same pressure point at the same temperature point in each adjacent two rounds of temperature cycles is greater than the second preset threshold value comprises:

[0024] The average value of the output data corresponding to each pressure point at each temperature point of the silicon piezoresistive pressure sensor in each round of temperature cycles in S6 is calculated.

[0025] The absolute value of the difference between the average values of the two rounds of output data corresponding to the same pressure point at the same temperature point in each adjacent two rounds of temperature cycles is calculated, and it is determined whether the maximum value of all the absolute values is greater than the second preset threshold value.

[0026] Further, the first preset threshold value, the second preset threshold value and the third preset threshold value are not greater than the design precision index of the silicon piezoresistive pressure sensor.

[0027] The technical scheme of the present application provides a rapid evaluation method for the stability of a silicon piezoresistive pressure sensor. The method first performs an environmental stress screening process of random vibration-temperature and pressure cycle-random vibration, collects data in the environmental stress screening process, and sets relevant criteria. On the one hand, it eliminates faulty sensors, and on the other hand, it releases the residual stress inside the silicon piezoresistive pressure sensor to make its performance index tend to be stable. Then, the silicon piezoresistive pressure sensor after the release of residual stress is continuously monitored for performance, and the long-term stability error of the sensor in one year or more years is calculated from the test data. The method can realize rapid and quantitative evaluation of the stability of the sensor. The method is simple, easy to understand, and convenient and effective to implement. By combining with relevant automatic test equipment, the method can realize batch rapid evaluation of the stability of the sensor, thereby effectively improving the production efficiency and reducing the production cost. BRIEF DESCRIPTION OF DRAWINGS

[0028] The accompanying drawings, which are included to provide a further understanding of the embodiments of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the principles of the application. It is to be understood that the drawings are solely for purposes of illustration to aid in the description and that the application is not limited to the specific arrangements, devices, and methods depicted in the drawings.

[0029] Figure 1 A flow chart of a method for rapidly evaluating the stability of a silicon piezoresistive pressure sensor is shown. DETAILED DESCRIPTION

[0030] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings of the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. The description of the at least one example embodiment is actually only illustrative, but not intended to limit the application and its application or use in any way. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the present application.

[0031] It should be noted that the terms used herein are only intended to describe specific embodiments, and are not intended to limit the exemplary embodiments according to the present application. As used herein, the singular form is intended to include the plural form, unless the context clearly indicates otherwise, and it should also be understood that when the terms "comprise" and / or "include" are used in the specification, there is a reference to the presence of a feature, step, operation, device, component, and / or combinations thereof.

[0032] Unless specifically stated otherwise, the relative arrangements, numerical expressions, and numerical values of the components and steps set forth in these embodiments do not limit the scope of the application. At the same time, it should be understood that the sizes of the various parts shown in the drawings are not drawn in proportion to the actual proportions. The techniques, methods, and devices known to those of ordinary skill in the relevant art can not be discussed in detail, but should be considered as part of the authorized specification, if appropriate. In all examples shown and discussed herein, any specific value should be interpreted as merely exemplary, and not as a limitation. Therefore, other examples of exemplary embodiments can have different values. It should be noted that similar reference numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0033] The specific embodiments according to the present application provide a rapid evaluation method for the stability of a silicon piezoresistive pressure sensor, which comprises:

[0034] S1, performing performance testing on the silicon piezoresistive pressure sensor to obtain performance testing data;

[0035] S2, performing one random vibration on the silicon piezoresistive pressure sensor after the performance testing in S1, and performing performance testing on the silicon piezoresistive pressure sensor after the random vibration to obtain performance testing data;

[0036] S3, judging whether the variation of the performance testing data obtained in S1 and S2 is greater than a first preset threshold value, if yes, turning to S4, and if no, turning to S6;

[0037] S4, repeating S2, and judging whether the variation of the performance testing data before and after repeating S2 is greater than the first preset threshold value, if yes, turning to S5, and if no, turning to S6;

[0038] S5, repeating S4, and stopping the repetition and eliminating the silicon piezoresistive pressure sensor when the repetition number reaches a preset upper limit of vibration number, and judging that the eliminated silicon piezoresistive pressure sensor is a faulty sensor;

[0039] S6, adjusting the temperature of the environment where the silicon piezoresistive pressure sensor is located to make it circulate at multiple preset temperature points in turn, adjusting the pressure of the environment at each preset temperature point to make it circulate multiple times to reach multiple preset pressure points, and collecting the output data corresponding to each pressure point at each temperature point in each round of temperature circulation of the silicon piezoresistive pressure sensor;

[0040] S7, performing performance testing on the silicon piezoresistive pressure sensor obtained in S6, performing one random vibration, and performing performance testing again after the random vibration to obtain the performance testing data of the silicon piezoresistive pressure sensor before and after the random vibration;

[0041] S8, judging whether the maximum value of the variation of the output data corresponding to the same pressure point at the same temperature point in each adjacent two rounds of temperature circulation in S6 is greater than a second preset threshold value, if yes, turning to S9, and if no, turning to S11;

[0042] S9, judging whether the variation of the performance testing data before and after the random vibration in S7 is greater than a third preset threshold value, if yes, turning to S10, and if no, turning to S11;

[0043] S10, repeating S1 to S9, and stopping the repetition and eliminating the silicon piezoresistive pressure sensor when the repetition number reaches a preset repetition number, and judging that the eliminated silicon piezoresistive pressure sensor is a faulty sensor;

[0044] S11, performing continuous performance monitoring on the silicon piezoresistive pressure sensor obtained in S8 and / or S9 for a preset time length to obtain a short-term stability error within the preset time length, and calculating a long-term stability error within one year or more years according to the short-term stability error within the preset time length.

[0045] By using such a configuration, a rapid evaluation method for the stability of a silicon piezoresistive pressure sensor is provided. The method first performs an environmental stress screening process of random vibration-temperature and pressure cycle-random vibration, collects data in the environmental stress screening process, and sets relevant criteria. On the one hand, faulty sensors are removed, and on the other hand, the residual stress in the silicon piezoresistive pressure sensor is released to make the performance indicators of the sensor tend to be stable. Then, the silicon piezoresistive pressure sensor after the residual stress is released is continuously monitored, and the long-term stability error of the sensor within one year or more years is calculated according to the test data, so that the rapid quantitative evaluation of the stability of the sensor can be realized. The method is simple, easy to understand, and convenient and effective to implement. By combining with relevant automatic test equipment, the rapid evaluation of the stability of the sensor in batches can be realized, and the production efficiency is effectively improved and the production cost is reduced. Compared with the prior art, the technical scheme of the present application can solve the technical problem that the long test time of the stability indicators of the sensor in the prior art leads to the difficulty in rapid evaluation.

[0046] In actual application, the preset vibration times in S5, the cycle times of temperature and pressure in S6, and the preset repetition times in S10 are determined according to actual conditions. The performance of the sensor before and after random vibration is tested, and the test points should cover the pressure range and the working temperature range of the sensor. Specifically, the test pressure points can be selected at equal intervals in the pressure range, the test temperature points can be selected as three temperature points of room temperature, the upper limit of the working temperature, and the lower limit of the working temperature, and the test points selected before and after random vibration remain the same. The first preset threshold value, the second preset threshold value, and the third preset threshold value are not greater than the design accuracy indicators of the silicon piezoresistive pressure sensor. The test conditions of the continuous performance monitoring can remain the same as the test conditions of the performance test before and after random vibration, or the performance monitoring can be performed on the pressure points and temperature points that are focused on as test points. In addition, the preset time length of the continuous performance monitoring is not less than one week, and the number of continuous performance monitoring times within the preset time length is not less than 3. In this way, the speed and accuracy of the stability evaluation can be considered.

[0047] Further, in the random vibration of S2 and S7, the direction perpendicular to the pressure-sensitive chip of the silicon piezoresistive pressure sensor is taken as the vibration direction. In this way, the residual stress can be released to the greatest extent, the performance of the sensor can be stabilized as soon as possible, and the test time can be saved.

[0048] Further, in the embodiment of the present application, the step S6 of judging whether the maximum of the variation of the two round output data corresponding to the same pressure point at the same temperature point in each two adjacent temperature cycles is greater than the second preset threshold value comprises:

[0049] calculating the average value of the output data of the silicon piezoresistive pressure sensor corresponding to each pressure point at each temperature point in each temperature cycle in the step S6;

[0050] calculating the absolute value of the difference between the average values of the two round output data corresponding to the same pressure point at the same temperature point in each two adjacent temperature cycles, and judging whether the maximum of all the absolute values of the differences is greater than the second preset threshold value.

[0051] That is to say, the silicon piezoresistive pressure sensor outputs a plurality of data at each pressure point at each temperature point in each temperature cycle, the average value of the plurality of data is calculated as the final value of the output data at the pressure point at the temperature point, for the two adjacent temperature cycles, the absolute value of the difference between the final values of the output data corresponding to the same pressure point at the same temperature point is calculated as the variation, and the maximum of all the variations is compared with the second preset threshold value. In this way, the accuracy of the evaluation can be improved.

[0052] Further, in the above embodiment, the step of performing the continuous performance monitoring of the silicon piezoresistive pressure sensor obtained in the steps S8 and / or S9 for a preset time length to obtain the short-term stability error in the preset time length comprises: calculating the difference between the maximum value and the minimum value of the output of the silicon piezoresistive pressure sensor at each test point in the performance monitoring process, and taking the maximum of all the differences as the short-term stability error in the preset time length.

[0053] Specifically, in the embodiment of the present application, the long-term stability error in one year or more years is calculated according to the short-term stability error in the preset time length by the following formula:

[0054]

[0055] In the above formula, δ C represents the long-term stability error, δ D represents the short-term stability error in the preset time length, t represents the preset time length, T represents the calculation time length of the long-term stability error, and V represents the full-scale output of the silicon piezoresistive pressure sensor.

[0056] In order to more clearly understand the rapid evaluation method of the stability of the silicon piezoresistive pressure sensor provided by the present application, the following will be combined with Figure 1 In order to more clearly understand the rapid evaluation method of the stability of the silicon piezoresistive pressure sensor provided by the present application, the following will be combined with

[0057] In this embodiment, the stability of 10 silicon piezoresistive pressure sensors produced in a batch is rapidly evaluated. The working temperature range of the batch of sensors is -45℃ to 85℃, the pressure range is 5kPa to 100kPa, and the design precision index is better than 0.1%FS, that is, the test error is not greater than 100Pa.

[0058] As shown in Figure 1 , first, the performance of the batch of sensors is tested. The test temperature points are 25℃, -45℃ and 85℃, and the pressure test points are 5kPa, 10kPa, 20kPa, 30kPa, 40kPa, 50kPa, 60kPa, 70kPa, 80kPa, 90kPa and 100kPa. The test data is recorded.

[0059] Then, the environmental stress screening test of the batch of sensors is carried out. The test process is random vibration-temperature and pressure cycle-random vibration.

[0060] In the random vibration, the direction perpendicular to the pressure sensitive chip of the sensor is selected as the vibration direction, the vibration level is 6.06g, and the vibration time is 5min. After the vibration is completed, the performance of the sensor is repeatedly tested, and the test data is recorded. By comparing the test data before and after the random vibration, the output of the sensor changes to a certain extent, which reflects the effect of stress release in the sensor. The output change value of the sensor is not greater than the first preset threshold value, and the next step is entered.

[0061] In the temperature and pressure cycle, the temperature range of -45℃ to 85℃ is set, the temperature change rate is 10℃ / min, the temperature is kept for 1h after reaching the temperature, the cycle number is set to 10, and the power is kept on throughout the process. After the temperature cycle reaches the holding time, the module (silicon piezoresistive pressure sensor) is subjected to 3 times of air pressure cycle, 1kPa and 100kPa are selected as the pressure points each time, and the measurement value is recorded after the pressure is stabilized. The maximum value of the output change of each sensor at each test pressure point (at the same temperature point and pressure point) in two adjacent cycles is recorded. According to the module output size and precision requirement, the change threshold value is set to 100μV (full scale output 100mV, 0.1%FS precision is 100μV), which is used as the stability evaluation criterion.

[0062] After the temperature and pressure cycle, the second random vibration condition is consistent with the first random vibration condition, and the test condition before and after the vibration is also consistent with the first one. The test data is recorded.

[0063] After the environmental stress screening test is completed, the data recorded in the test process are comprehensively processed and analyzed to determine the performance change of each sensor in the test process. If the sensor in the temperature and pressure cycle meets the stability evaluation criterion, and the sensor output change value before and after the second random vibration also meets the stability evaluation criterion, it is determined that the sensor has preliminarily realized performance stabilization, and can enter the next step. The sensors that do not meet the stability evaluation criterion repeat the above steps to determine whether they can meet the stability evaluation criterion after the second test.

[0064] In this embodiment, 9 sensors can meet the stability evaluation criterion in 10 temperature and pressure cycles, and another one fails to meet the stability criterion after 10 cycles. After the second random vibration, the 9 sensors that meet the criterion in the previous step still meet the criterion, and the sensor that fails to meet the criterion still fails to meet the criterion. The sensor that fails to meet the stability evaluation criterion after the environmental stress screening test is repeated once, and meets the criterion during the temperature and pressure cycle of the second test.

[0065] After the batch of sensors complete the environmental stress screening test and meet the stability evaluation criterion, a continuous performance monitoring of 15 days, a total of 8 times, is carried out, with a test interval of 2 days. The test conditions are consistent with those before and after the random vibration. The test data are collected and recorded, the difference between the maximum and minimum values at each test point within 15 days is calculated, the maximum value among all the differences is taken as the stability error of the sensor within 15 days at the test point, and the annual stability error is calculated based on this.

[0066] In this embodiment, the maximum error of a certain sensor within 15 days is about 5 μV, so the annual stability error of the sensor is

[0067] In summary, the present application provides a rapid evaluation method for the stability of a silicon piezoresistive pressure sensor. The method first performs an environmental stress screening process of random vibration-temperature and pressure cycle-random vibration, collects data in the environmental stress screening process, and sets relevant criteria. On the one hand, faulty sensors are removed, and on the other hand, the residual stress in the silicon piezoresistive pressure sensor is released to make its performance indicators tend to be stable. Then, the silicon piezoresistive pressure sensor after releasing the residual stress is continuously monitored for performance, and the long-term stability error of the sensor within one year or more years is calculated based on the test data, so that the rapid and quantitative evaluation of the stability of the sensor can be realized. The method is simple, easy to understand, and convenient and effective to implement. By combining with related automatic test equipment, the batch rapid evaluation of the stability of the sensor can be realized, thereby effectively improving the production efficiency and reducing the production cost. Compared with the prior art, the technical scheme of the present application can solve the technical problem of long test time of sensor stability indicators in the prior art, which makes it difficult to realize rapid evaluation.

[0068] For purposes of the description hereinafter, spatial

[0069] In addition, it should be noted that the use of "first", "second", etc. words to describe various components is only intended to distinguish a certain component from another, and the above words do not have special meanings unless otherwise stated, and therefore cannot be understood as a limitation on the scope of protection of the present application.

[0070] The above description is merely illustrative of the application, and is not intended to limit the application. Any modifications, equivalent replacements, improvements, and the like made within the spirit and principle of the application should be included in the scope of protection of the application.

Claims

1. A method for rapid evaluation of stability of a silicon piezoresistive pressure sensor, characterized by, The method comprises: S1, performance test is performed on the silicon piezoresistive pressure sensor to obtain performance test data; S2, one-time random vibration is performed on the silicon piezoresistive pressure sensor after the performance test in S1, and performance test is performed on the silicon piezoresistive pressure sensor after the one-time random vibration to obtain performance test data; S3, it is judged whether the variation of the performance test data obtained in S1 and S2 is greater than a first preset threshold value, if yes, it is turned to S4, if no, it is turned to S6; S4, S2 is repeated, and it is judged whether the variation of the performance test data before and after the repeated S2 is greater than the first preset threshold value, if yes, it is turned to S5, if no, it is turned to S6; S5, S4 is repeated, and when the repeated number reaches a preset upper limit of vibration number, the repetition is stopped and the silicon piezoresistive pressure sensor is rejected, and it is judged that the rejected silicon piezoresistive pressure sensor is a faulty sensor; S6, the temperature of the environment where the silicon piezoresistive pressure sensor is located is adjusted to make it circulate at a plurality of preset temperature points in turn, the pressure of the environment is adjusted to make it circulate a plurality of times to reach a plurality of preset pressure points at each preset temperature point, and the output data corresponding to each pressure point at each temperature point in each round of temperature circulation of the silicon piezoresistive pressure sensor is collected; S7, performance test is performed on the silicon piezoresistive pressure sensor obtained in S6, one-time random vibration is performed, and performance test is performed again after the one-time random vibration, and the performance test data of the silicon piezoresistive pressure sensor before and after the one-time random vibration is obtained; S8, it is judged whether the maximum value of the variation of the output data corresponding to the same pressure point at the same temperature point in each adjacent two rounds of temperature circulation in S6 is greater than a second preset threshold value, if yes, it is turned to S9, if no, it is turned to S11; S9, it is judged whether the variation of the performance test data before and after the random vibration in S7 is greater than a third preset threshold value, if yes, it is turned to S10, if no, it is turned to S11; S10, S1 to S9 are repeated, and when the repeated number reaches a preset repeated number, the repetition is stopped and the silicon piezoresistive pressure sensor is rejected, and it is judged that the rejected silicon piezoresistive pressure sensor is a faulty sensor; S11, the silicon piezoresistive pressure sensor obtained in S8 and / or S9 is continuously monitored for a preset time length to obtain a short-term stability error in the preset time length, and a long-term stability error in one year or more years is calculated according to the short-term stability error in the preset time length.

2. The method of claim 1, wherein, In the random vibration in S2 and S7, the direction perpendicular to the pressure sensitive chip of the silicon piezoresistive pressure sensor is taken as the vibration direction.

3. The method of claim 1, wherein, The continuous performance monitoring of the silicon piezoresistive pressure sensor obtained in S8 and / or S9 for a preset time length to obtain a short-term stability error in the preset time length comprises: calculating the difference between the maximum value and the minimum value of the output of the silicon piezoresistive pressure sensor at each test point in the performance monitoring process, and taking the maximum one of all the differences as the short-term stability error in the preset time length.

4. The method of claim 3, wherein, The long-term stability error in one year or more years is calculated according to the short-term stability error in the preset time length by the following formula: In the above formula, δ C represents the long-term stability error, δ D represents the short-term stability error within the preset time length, t represents the preset time length, T represents the calculation time length of the long-term stability error, and V represents the full-scale output of the silicon piezoresistive pressure sensor.

5. The method of claim 4, wherein, The preset time length is not less than one week, and the number of continuous performance monitoring in the preset time length is not less than 3 times.

6. The method of claim 1, wherein, The maximum value of the change of the two round output data corresponding to the same pressure point at the same temperature point in each adjacent two temperature cycles in the determining S6 is greater than the second preset threshold value, including: The average value of the output data corresponding to each pressure point at each temperature point in each temperature cycle of the silicon piezoresistive pressure sensor in the calculating S6 is calculated. The absolute value of the difference between the average values of the two round output data corresponding to the same pressure point at the same temperature point in each adjacent two temperature cycles is calculated, and it is judged whether the maximum value of all absolute values is greater than the second preset threshold value.

7. The method of claim 6, wherein, The first preset threshold value, the second preset threshold value and the third preset threshold value are not greater than the design accuracy index of the silicon piezoresistive pressure sensor.

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