Test probe and test system

Abstract

The utility model provides a test probe and a test system, the test probe is used for testing the piezoelectric coefficient of a piezoelectric material, the test probe applies stress to the piezoelectric material from the upper part of the piezoelectric material to the lower part of the piezoelectric material, the piezoelectric material responds to charges generated by the stress and is detected by a test detector, and meanwhile, the applied stress is tested by a piezoelectric stress sensor. A driving signal of the stress can be a pulse signal and / or an alternating signal, and furthermore, the driving signal is consistent with a working excitation signal of the piezoelectric material. Besides, the test probe can work at high frequency on the premise that the test probe is not close to the resonant frequency of the base membrane of the piezoelectric material to be tested, so that the piezoelectric coefficient obtained by testing the piezoelectric material is closer to the piezoelectric coefficient of the piezoelectric material in actual work. Meanwhile, the test probe works at high frequency, the time of acting on the piezoelectric material is correspondingly shortened, and the force of the applied stress is correspondingly reduced, so that physical damage to the piezoelectric material is avoided, and the risk of depolarization of the piezoelectric material is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of piezoelectric material detection, in particular to a test probe and a test system for testing the piezoelectric coefficient of a piezoelectric material. Background Art

[0002] The piezoelectric coefficient is the most important physical parameter of piezoelectric materials. The higher the piezoelectric coefficient, the more efficient the piezoelectric material's energy conversion. Piezoelectric materials are now finding applications in a growing number of fields, evolving from bulk materials to thin films. However, the testing equipment and methods for the piezoelectric coefficient have not seen significant improvement, failing to meet the testing needs of technological development and application expansion.

[0003] Methods for measuring the piezoelectric coefficient of piezoelectric materials include direct methods, quasi-static methods (Berlincourt method), resonance methods, laser interferometers, laser scanning vibrometers, and piezoelectric force microscopes. Laser interferometers, laser Doppler vibrometers, and piezoelectric force microscopes all utilize the inverse piezoelectric effect, measuring the piezoelectric coefficient by applying a pulsed voltage signal to the material to induce deformation. These methods require high-precision measurement of minute deformations, resulting in expensive equipment and low test efficiency, making them unsuitable for industrial testing of piezoelectric materials and devices. Direct, quasi-static, and resonance methods utilize the direct piezoelectric effect to measure the charge generated by the material under stress, offering simplicity and convenience. The resonance method offers the highest accuracy, but it places significant demands on the test sample shape to ensure that the sample operates in the fundamental mode, making it unsuitable for piezoelectric measurement in many practical materials and piezoelectric devices. Direct methods also suffer from zero-point drift.

[0004] Quasi-static devices are widely used in the testing of traditional bulk piezoelectric materials, but there are serious limitations when applied to the testing of thin-film piezoelectric materials. The testing principle of the quasi-static method is based on the positive piezoelectric effect. A low-frequency alternating force is applied to the piezoelectric material, generating alternating charges on the two end faces of the piezoelectric material. The mean square of the alternating charges is measured to obtain the stress-to-charge ratio - the piezoelectric coefficient. In the quasi-static method, the alternating force is provided by an electromagnetic driver on the base. Therefore, the alternating force has a low frequency, a long action time, and a high force, which can easily damage the physical properties of the film and cause the piezoelectric film to depolarize and lose its piezoelectric properties. Its measurement time may also be much longer than the time constant of the piezoelectric film. In terms of spatial setting, the alternating force is generated from below and cannot be applied to in-situ testing. Utility Model Content

[0005] The utility model provides a test probe and a test system for testing the piezoelectric coefficient of a piezoelectric material, so as to solve various defects and deficiencies in the piezoelectric coefficient test in the prior art.

[0006] One aspect of the present invention provides a test probe for testing the piezoelectric coefficient of a piezoelectric material. The test probe comprises:

[0007] a detection probe configured to apply stress to the piezoelectric material when contacting the piezoelectric material below the detection probe, and output a charge signal of charge generated by the piezoelectric material in response to the stress;

[0008] a vibration mechanism, located above the detection probe, configured to vibrate the detection probe in response to a received driving signal to apply the stress to the piezoelectric material;

[0009] a stress testing element disposed between the testing probe and the vibration mechanism, configured to measure and output a stress signal representing the stress applied to the piezoelectric material; and

[0010] The driving unit is communicatively connected to the vibration mechanism and sends the driving signal to the vibration mechanism to drive the vibration mechanism to vibrate.

[0011] Optionally, the stress testing element is a pressure sensor, and the pressure sensor is a piezoelectric pressure sensor.

[0012] Optionally, the driving signal is a pulse signal and / or an alternating signal.

[0013] Optionally, the driving signal is consistent with a working driving signal of the piezoelectric material.

[0014] Optionally, the test probe further includes a first output terminal and a second output terminal.

[0015] The first output end is connected to the detection probe to output the charge signal;

[0016] The second output end is connected to the stress testing element to output the stress signal.

[0017] Optionally, the piezoelectric vibration mechanism has an adjustable vibration frequency.

[0018] Optionally, the vibration mechanism and the detection probe are coaxially arranged.

[0019] Optionally, the test probe includes a conductive tip contacting the surface of the piezoelectric material, and the stress testing element is integrated in the test probe and is located at an end opposite to the conductive tip along the axial direction of the test probe.

[0020] Another aspect of the present invention provides a testing system for testing the piezoelectric coefficient of a piezoelectric material, comprising:

[0021] at least one test probe, wherein the test probe is the test probe according to any one of claims 1 to 8;

[0022] A carrying device, used for carrying the piezoelectric material to be tested, wherein the carrying device is located below the test probe so that the piezoelectric material on the carrying device is located below the test probe;

[0023] The processing unit receives and obtains the piezoelectric coefficient of the piezoelectric material according to the stress signal and the charge signal.

[0024] Optionally, the test system further includes a motion control system connected to the test probe to control the test probe to achieve three-dimensional motion.

[0025] As described above, the test probe and detection system for testing the piezoelectric coefficient of a piezoelectric material of the present invention have at least the following beneficial effects:

[0026] The test probe of the present invention is located above the piezoelectric material to be tested, and stress is applied to the piezoelectric material from above the piezoelectric material downward. The charge generated by the piezoelectric material in response to the stress is detected by the test probe, and the applied stress is tested by the piezoelectric stress sensor at the same time. The driving signal of the above stress can be a pulse signal and / or an alternating signal. Furthermore, the driving signal is consistent with the working excitation signal of the piezoelectric material. In addition, the test probe of the present invention can operate at a high frequency without being close to the basement membrane resonance frequency of the piezoelectric material to be tested, so that the piezoelectric coefficient obtained from the test of the piezoelectric material is closer to the piezoelectric coefficient of the piezoelectric material in actual operation. At the same time, when the test probe operates at a high frequency, the time it acts on the piezoelectric material becomes correspondingly shorter, and the strength of the applied stress is also correspondingly reduced. Therefore, no physical damage will be caused to the piezoelectric material, and there will be no risk of depolarization of the piezoelectric material.

[0027] In the test system of the present invention, the supporting device for supporting the piezoelectric material to be tested can be a film-forming chamber for growing a piezoelectric material film, that is, the test probe can be integrated into the piezoelectric material film-forming device, thereby enabling in-situ testing of the piezoelectric material in the film-forming chamber. The environment in which the piezoelectric material is located will not be changed during this test, and accordingly, its performance can be more completely maintained, so that the piezoelectric coefficient obtained by the test is closer to the actual piezoelectric coefficient of the piezoelectric material. At the same time, the piezoelectric coefficient test can also be performed at any stage of the piezoelectric material film-forming process to characterize the yield of the piezoelectric material film, which is conducive to improving the yield of the piezoelectric material film finally formed. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It shows the principle diagram of the quasi-static method test in the prior art.

[0029] Figure 2 Shown is a schematic structural diagram of the test probe of this application.

[0030] Figure 3 Shown is a schematic diagram of the test system of the present application.

[0031] Figure 4 A schematic diagram of a testing system is shown as another alternative embodiment.

[0032] Figure 5 Shown is the broadband response of the piezoelectric coefficient d33 of the piezoelectric material.

[0033] Figure 6 Shown is a flow chart of the test method of this application.

[0034] Figure 7a and Figure 7b Shown are the different operating modes of the test probe.

[0035] Figure 8 and Figure 9 Schematic diagram of test results showing peak-to-peak and integrated value signals.

[0036] Description of Reference Numerals

[0037] 100. Test probe; 101. Vibration mechanism; 102. Stress test element; 103. Detection probe; 104. Motion control system; 105. Drive unit; 106. Amplifier; 107. Signal collector; 108. Piezoelectric material; 109. Carrying device; 110. Processing unit; 111. First output terminal; 112. Second output terminal. DETAILED DESCRIPTION

[0038] The following describes the embodiments of the present invention through specific examples. Those skilled in the art will readily understand the other advantages and benefits of the present invention from the disclosure herein. The present invention may also be implemented or applied through various other specific embodiments, and the details in this specification may be modified or altered based on different perspectives and applications without departing from the spirit of the present invention.

[0039] Take an ultrasonic sensor system, for example, which uses piezoelectric materials to transmit and receive ultrasonic waves. Piezoelectric materials can stretch or contract (e.g., deform to produce strain in response to an applied mechanical force or pressure that stresses the piezoelectric material), thereby generating surface charge, which in turn may generate a voltage and / or current across the piezoelectric material. Conversely, applying a voltage to a piezoelectric material causes it to stretch or contract. Therefore, a piezoelectric material can be strained by applying a signal to it to generate ultrasonic waves. Conversely, a piezoelectric material can be strained by an ultrasonic wave (e.g., an ultrasonic wave generated or emitted as part of a reflection from an object such as a finger, as discussed herein) to produce a charge that can be sampled to provide a signal representative of the object from which it was reflected.

[0040] A piezoelectric material can be characterized in part according to its piezoelectric coefficient d33, indicating its piezoelectricity (e.g., as a non-limiting example, the piezoelectric coefficient d33 can indicate piezoelectricity), which is based on the ratio of the charge generated by the piezoelectric material under stress to the force generating the stress on the piezoelectric material. The piezoelectric coefficient d33, or the piezoelectric strain constant d33, is typically measured in the thickness direction of a relatively thin sheet of piezoelectric material. Figure 1 The schematic diagram of the quasi-static method for testing the piezoelectric coefficient of a bulk piezoelectric material in the prior art is shown, wherein the test probe includes an upper test probe 1 and a lower test probe 2, the piezoelectric material 3 is located between the upper and lower test probes, and the lower test probe 2 is connected to an electromagnetic driver 4, which drives the lower test probe 2 to apply stress to the piezoelectric material from the bottom of the piezoelectric material 3. The force applied by the electromagnetic driver to the lower test probe is a low-frequency alternating force, and alternating charges are generated on the upper and lower end faces of the piezoelectric material. The mean square value of the alternating charge is measured to obtain the ratio of stress to charge, i.e., the piezoelectric coefficient. The above-mentioned alternating force has a low frequency, a long action time, and a high force, which can easily damage the physical properties of the film and cause the piezoelectric film to depolarize and lose its piezoelectric properties. Its measurement time may also be much longer than the time constant of the piezoelectric film.

[0041] To overcome the aforementioned defects and deficiencies of the prior art, the first embodiment of the present invention provides a test probe for testing the piezoelectric coefficient of a piezoelectric material, and in particular, for in-situ testing the piezoelectric coefficient of a piezoelectric film. A detailed description will now be given using specific embodiments. Those skilled in the art will appreciate that the teachings of this application can be applied in a variety of different ways. The embodiments described herein can be implemented in any device, apparatus, or system for ultrasonic sensing. Furthermore, it is contemplated that the described embodiments can be included in or associated with a variety of electronic devices, including, but not limited to, mobile phones, multimedia Internet-enabled cellular phones, mobile television receivers, wireless devices, smartphones, smart cards, bracelets, armbands, wristbands, rings, headbands, patches, and other wearable devices, personal digital assistants (PDAs), wireless email receivers, handheld or portable computers, netbooks, notebooks, smartbooks, tablet computers, and computers. Therefore, these teachings are not intended to be limited to the embodiments described solely in the accompanying drawings, but rather have broad applicability, as will be apparent to those skilled in the art.

[0042] Example 1

[0043] This embodiment provides a test probe for testing the piezoelectric coefficient of a piezoelectric material. Figure 2 As shown, the test probe 100 of this embodiment includes a detection probe 103, a stress testing element 102, a vibration mechanism 101 and a driving unit 105. The detection probe 103 is configured to apply stress to the piezoelectric material 108 when in contact with the piezoelectric material 108, and output a charge signal of the charge generated by the piezoelectric material 108 in response to the stress. The stress testing element 102 is configured to measure and output a stress signal representing the stress applied to the piezoelectric material 108. The vibration mechanism 101 is located above the detection probe 103 and is configured to vibrate the detection probe 103 in response to a received driving signal to apply the stress to the piezoelectric material 108. The driving unit 105 is configured to receive a stress signal corresponding to the stress, generate a corresponding driving signal based on the stress signal, and send the driving signal to the vibration mechanism 101.

[0044] The piezoelectric material 108 to be tested is embodied as a thin film layer formed on a substrate. The piezoelectric material 108 may be a ferroelectric polymer, such as polyvinylidene fluoride (PVDF) and polyvinylidene fluoride-trifluoroethylene (PVDF-TrFE) copolymer, polyvinylidene chloride (PVDC) homopolymer and copolymer, polytetrafluoroethylene (PTFE) homopolymer and copolymer, and diisopropylammonium bromide (DIPAB).

[0045] like Figure 2As shown, the test probe may include a conductive tip that contacts the surface of the piezoelectric material 108. The conductive tip contacts the surface of the piezoelectric material 108 and applies a predetermined stress to the piezoelectric material 108. As described above, the piezoelectric material 108 generates a charge on its surface under the action of this stress. Optionally, the conductive tip of the test probe includes a first output terminal 111 that can be electrically connected to provide a charge signal. The charge signal is provided from the first output terminal 111 to an externally connected functional unit. The charge signal corresponds to the charge generated on the surface of the piezoelectric material 108.

[0046] In an optional embodiment, the stress testing element 102 can be mechanically coupled to a conductive tip, so that the stress testing element 102 can generate a stress signal corresponding to the stress applied to the piezoelectric material 108, thereby being able to measure the stress applied to the piezoelectric material 108 in real time. Optionally, the stress testing element 102 can be a stress sensor, and further, a piezoelectric stress sensor. The use of a piezoelectric stress sensor can more accurately test different forms of stress applied to the surface of the stress material. Figure 2 As shown, stress testing element 102 is integrated into test probe 100 and located at the end of test probe 103 opposite the conductive tip along the axial direction of test probe 103. Test probe 100 is provided with a second output terminal 112 on stress testing element 102. This second output terminal 112 provides a stress signal corresponding to the stress applied to the surface of piezoelectric material 108 to externally connected functional units. The stress signal applied to the surface of piezoelectric material 108 and the charge signal on the surface of piezoelectric material 108 can be simultaneously obtained through the first output terminal 111 and the second output terminal 112. Based on this stress signal and pressure signal, the piezoelectric coefficient d33 of piezoelectric material 108 can be obtained.

[0047] Also refer to Figure 2 The test probe 100 is also provided with a vibration mechanism 101. The vibration mechanism 101 is used to vibrate the detection probe 103 based on the received driving signal to generate a corresponding form of vibration, thereby enabling the detection probe 103 to apply a corresponding form of stress to the surface of the piezoelectric material 108. The vibration mechanism 101 can be a piezoelectric vibration mechanism, etc. The piezoelectric vibration mechanism is not only small in size and light in weight, and is easy to integrate into a movable probe, but also has a high vibration frequency. The vibration frequency can be adjusted by the driving unit and can match the frequency of the object under test, so it can generate vibration in response to different driving signals. In order to be able to drive the detection probe 103 to vibrate, as Figure 2 As shown, the vibration mechanism 101 is located at the end opposite to the conductive tip of the detection probe 103 along the axial direction of the detection probe 103. Preferably, the vibration mechanism 101 and the detection probe 103 are coaxially arranged to increase the accuracy of the vibration mechanism driving the detection probe 103 and avoid the deformation of the detection probe 103 due to the different axes causing damage to the piezoelectric film. Figure 2 As shown, the stress testing element 102 is located between the vibration mechanism 101 and the detection probe 103 to accurately detect a stress signal corresponding to the stress generated in the detection probe 103 by the vibration of the vibration mechanism 101 .

[0048] like Figure 2 As shown, the driving unit 105 is connected to the vibration mechanism 101, and the driving unit 105 is also connected to the external control terminal, receives the driving signal sent by the external control terminal, and drives the vibration mechanism 101 to generate a corresponding form of vibration according to the driving signal. In an optional embodiment, the driving signal can be a pulse excitation signal, an alternating excitation signal, or a combination signal of a pulse excitation signal and an alternating excitation signal arranged in a predetermined form. Regardless of which signal is used, the above signal can be set to a form consistent with the actual working signal of the piezoelectric material 108 according to the actual working environment and working requirements of the piezoelectric material 108 to be tested. Both tests of the pulse excitation signal and the alternating excitation signal can perform time domain / frequency domain cross-analysis on the piezoelectric material 108, providing a richer piezoelectric performance test.

[0049] In addition, the driving frequency of the above-mentioned driving signal is a high-frequency signal as high as possible that is not close to the resonance frequency of the basement membrane of the test sample, and of course it can also be a low-frequency signal. For example, it can be a specific frequency in the range of 10Hz to 100MHz, such as 10Hz, 100Hz, 1000Hz, 0.01MHz, 0.1MHz, 1MHz, 10MHz, 100MHz and / or other intermediate frequencies, thereby testing the piezoelectric coefficient of the piezoelectric material 108 at a certain frequency. Optionally, the driving frequency of the driving signal can be in the range of several hertz to tens of megahertz. For example, a frequency range between 1MHz and 10MHz or between 5MHz and 30MHz or higher, thereby making the piezoelectric coefficient obtained by the test infinitely close to the actual piezoelectric coefficient value of the piezoelectric material 108.

[0050] Example 2

[0051] This embodiment provides a testing system for testing the piezoelectric coefficient of the piezoelectric material 108. Figure 3 As shown, the testing system includes at least one testing probe 100 , a carrying device 109 for carrying a piezoelectric material 108 to be tested, and a processing unit 110 .

[0052] The test probe 100 is the test probe 100 described in the first embodiment. For details, please refer to the description of the first embodiment, which will not be repeated here.

[0053] The carrier 109 can be any device capable of supporting the piezoelectric material 108 to be tested. The carrier 109 is located below the test probe 100. That is, when testing is in progress, the conductive tip of the detection probe 103 of the test probe 100 is directly facing the piezoelectric material 108 above the carrier 109. Positioning the test probe 100 above the carrier 109 allows for in-situ measurement of the piezoelectric material 108 after film formation, while also reducing system footprint.

[0054] The carrying device 109 is, for example, a carrying platform on a test machine for testing. In an optional embodiment of this embodiment, the carrying device 109 is a carrying platform in the film forming chamber of the film forming machine of the piezoelectric material 108. A substrate for forming the piezoelectric material 108, such as a semiconductor substrate, a glass substrate, etc., is placed on the carrying platform. The piezoelectric material 108 is formed into a film on the exposed surface of the substrate. At this time, the test probe 100 can also be integrated into the film forming chamber of the piezoelectric material 108. When the film forming of the piezoelectric material 108 is completed or the film forming reaches a certain stage of the process, the test probe 100 can be moved to the top of the piezoelectric material 108 as needed to test the piezoelectric coefficient of the film forming layer of the piezoelectric material 108. The above setting can realize in-situ testing of the piezoelectric material 108 after the film is formed, without changing the environment in which the piezoelectric material 108 is located, so that a measurement value closer to the true piezoelectric coefficient of the piezoelectric material 108 can be obtained. In addition, real-time piezoelectric coefficient testing of the film-forming process of the piezoelectric material 108 can be realized to obtain real-time data of the film-forming process of the piezoelectric material 108. The real-time data can reflect whether there are abnormalities in the film-forming process of the piezoelectric material 108, which is beneficial to monitoring the film-forming process and providing uniformity and yield of the film-forming process.

[0055] The above-mentioned processing unit 110 can be a computer, an oscilloscope or other devices capable of performing data acquisition and data processing. The processing unit 110 is connected to the first output terminal 111 and the second output terminal 112 of the test probe, and is also connected to the driving unit 105 of the vibration mechanism 101. The processing unit 110 reads the charge signal from the first output terminal 111 and the stress signal from the second output terminal 112. In order to read the above-mentioned charge signal and pressure signal more accurately, a signal amplifier 106 (for example, a charge amplifier, a transimpedance amplifier, etc.) is respectively provided between the first output terminal 111 and the processing unit 110 and between the second output terminal 112 and the processing unit 110. A signal collector 107 is provided behind the amplifier 106, and the signal collector 107 is communicatively connected to the processing unit 110. On the one hand, the processing unit 110 can obtain the peak-to-peak value of the above-mentioned signal, and obtain the piezoelectric coefficient of the piezoelectric material 108 based on the peak-to-peak value. On the other hand, the integral value of the above-mentioned charge signal and voltage signal can also be calculated, and the piezoelectric coefficient of the piezoelectric material 108 can be obtained based on the integral value, such as Figure 5As shown, the piezoelectric coefficient thus measured includes the limited broadband response of the piezoelectric material 108 . Compared with only the root-peak-to-peak value test of the piezoelectric signal, the piezoelectric coefficient measured based on the integrated signal is closer to the actual situation of the piezoelectric material 108 .

[0056] In addition, the test system of this embodiment also includes a motion control system 104. The motion control system 104 can at least move the test probe in a direction perpendicular to the plane of the piezoelectric material 108, and preferably can move the test probe in three dimensions, so as to facilitate flexible adjustment of the test range and test position of the test probe. The motion control system 104 can be a system capable of motion control, such as a PLC.

[0057] In an optional embodiment, if Figure 3 As shown, the test system may include the above-mentioned test probe, which can move sequentially in three-dimensional space under the control of the motion control system 104 to achieve multi-point testing of the piezoelectric material 108. In another optional embodiment, as Figure 4 As shown, the test system includes multiple test probes, which are spaced apart and can test different points on the piezoelectric material 108. This arrangement of the test probes can improve test efficiency, and the measurement accuracy of the piezoelectric coefficient can be further optimized based on the results of the multi-point measurements.

[0058] This embodiment also provides a method for testing the piezoelectric coefficient of the piezoelectric material 108 using the test probe 100. Taking the film-formed piezoelectric material 108 in the film-forming chamber as an example, first move the test probe 100 to the top of the piezoelectric material 108. Then, Figure 6 The following specific steps are performed as shown:

[0059] A driving signal of a predetermined form is sent to the vibration mechanism 101 of the test probe. In an optional embodiment, the driving signal is a pulse signal and / or an alternating signal. Figure 7a The pulse signal shown can be used to perform time domain analysis on the piezoelectric material 108. Figure 7b The alternating signal shown can be used to perform frequency domain analysis on the piezoelectric material 108. Therefore, time-domain / frequency-domain crossover analysis can be performed on the piezoelectric layer material 108 based on the type of drive signal sent, providing a more comprehensive piezoelectric performance test. In this embodiment, a signal consistent with the actual operating excitation signal is applied to the piezoelectric material 108. In response to this drive signal, the test probe contacts the piezoelectric material 108 and applies stress to the piezoelectric material 108.

[0060] The stress testing component 102 simultaneously tests and outputs a stress signal corresponding to the stress.

[0061] At the same time, the test probe measures the charge signal of the piezoelectric material 108 in response to the charge generated by the stress;

[0062] The piezoelectric coefficient of the piezoelectric material 108 is obtained according to the tested stress signal and charge signal.

[0063] In an optional embodiment, if Figure 8 As shown, the voltage value of the peak charge signal corresponding to the positive peak value and / or negative peak value of the charge signal is obtained;

[0064] The voltage value of the peak stress signal corresponding to the positive peak value and / or the negative peak value of the stress signal is obtained; and the piezoelectric coefficient is determined according to the voltage value of the peak charge signal and the voltage value of the peak stress signal.

[0065] In another optional embodiment, Figure 9 As shown, the voltage integral value corresponding to the charge signal is obtained; the voltage integral value corresponding to the stress signal is obtained; and the piezoelectric coefficient is determined according to the voltage integral value corresponding to the charge signal and the voltage integral value corresponding to the stress signal.

[0066] Another embodiment of the present application provides an electronic device comprising a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other via the communication bus; the memory is configured to store a computer program; and the processor is configured to implement the aforementioned method when executing the program stored in the memory. Also provided is a computer-readable storage medium, wherein the computer program is stored in the computer-readable storage medium, and when executed by the processor, the aforementioned method is implemented. Computer-readable media can, for example, be on a non-transitory medium or transmitted as one or more instructions or codes. Computer-readable media include computer storage media and communication media, including any medium that can transfer a computer program from one location to another. A storage medium can be any available medium that is accessible to a computer. By way of example and not limitation, non-transitory media can include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the required instructions or program code in the form of data structures accessible by a computer. Furthermore, any connection can be appropriately referred to as a computer-readable medium. Disk and disc, as used herein, include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk, and Blu-ray disc, where disks typically reproduce data magnetically, while discs reproduce data optically using lasers, and combinations of the above are also included within the scope of computer-readable media. Additionally, the operations of a method or algorithm may reside as one or any combination or set of code and instructions on a machine-readable medium and a computer-readable medium, which may be incorporated into a computer program product.

[0067] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical principles disclosed in the present invention are intended to be covered by the claims of the present invention.

Claims

1. A test probe for testing the piezoelectric coefficient of a piezoelectric material, characterized in that: The test probe comprises: a detection probe configured to apply stress to the piezoelectric material when contacting the piezoelectric material below the detection probe, and output a charge signal of charge generated by the piezoelectric material in response to the stress; a vibration mechanism, located above the detection probe, configured to vibrate the detection probe in response to a received driving signal to apply the stress to the piezoelectric material; a stress testing element disposed between the testing probe and the vibration mechanism, configured to measure and output a stress signal representing the stress applied to the piezoelectric material; and The driving unit is communicatively connected to the vibration mechanism and sends the driving signal to the vibration mechanism to drive the vibration mechanism to vibrate.

2. The test probe according to claim 1, wherein: The stress testing element is a pressure sensor, and the pressure sensor is a piezoelectric pressure sensor.

3. The test probe according to claim 1, wherein: The driving signal is a pulse signal and / or an alternating signal.

4. The test probe according to claim 1, wherein: The driving signal is consistent with the working driving signal of the piezoelectric material.

5. The test probe according to claim 1, wherein: Also includes a first output terminal and a second output terminal, The first output end is connected to the detection probe to output the charge signal; The second output end is connected to the stress testing element to output the stress signal.

6. The test probe according to claim 1, wherein: The vibration mechanism is a piezoelectric vibration mechanism, and the vibration frequency of the piezoelectric vibration mechanism is adjustable.

7. The test probe according to claim 1, wherein: The vibration mechanism is coaxially arranged with the detection probe.

8. The test probe according to claim 1, wherein: The detection probe includes a conductive tip contacting the surface of the piezoelectric material. The stress testing element is integrated in the test probe and is located at an end opposite to the conductive tip along the axial direction of the detection probe.

9. A testing system for testing the piezoelectric coefficient of a piezoelectric material, characterized in that: include: At least one test probe, wherein the test probe is the test probe according to any one of claims 1 to 8; A carrying device, used for carrying the piezoelectric material to be tested, wherein the carrying device is located below the test probe so that the piezoelectric material on the carrying device is located below the test probe; The processing unit receives and obtains the piezoelectric coefficient of the piezoelectric material according to the stress signal and the charge signal.

10. The test system according to claim 9, characterized in that: It also includes a motion control system connected to the test probe to control the test probe to achieve three-dimensional motion.

Images