A synchronous transient force-electric coupling test chip structure and a preparation method thereof

Abstract

The application discloses a synchronous transient force-electric coupling test chip structure and a preparation method thereof. The chip functional area comprises a support beam, a tensile thermal actuator, an electrostatic actuator, a sample table, a strain capacitance sensor, a stress capacitance sensor, an electrode lead pressure welding block and a substrate. The substrate is used for bearing a device layer, the device layer is provided with a substrate hollow structure below, and a connecting piece made of high-resistance silicon or glass is used for mechanically connecting and electrically isolating the actuator and the sensor. The device is provided with an active time judgment algorithm of a stress compensation control part, and synchronous transient force-electric coupling test of a micro-nano material sample is realized.

Description

TECHNICAL FIELD

[0001] The application relates to a MEMS force-electric coupling test chip, in particular to a synchronous and transient force-electric coupling test chip for the field of force and electric material parameter testing of low-dimensional or thin film materials. BACKGROUND

[0002] In the past few decades, due to the unique mechanical, electrical and thermal properties of nanomaterials, they have been widely used in emerging fields such as manufacturing electronic devices, solar energy conversion, promoting chemical reactions, synthetic fibers, micro-battery manufacturing, nanoelectromechanical systems (NEMS) and stretchable electronics. Therefore, the mechanical and electrical behavior of nanomaterials is one of the key research areas in materials science. The mechanical and electrical properties of nanomaterials are closely related to their nanoscale deformation mechanism, resulting in significant differences in their mechanical and electrical properties compared with macroscopic materials. Therefore, developing a test system that can conveniently and real-time measure and realize in-situ observation of the microstructure and force and electrical properties of nanomaterials in SEM / TEM is of great significance for improving the reliability of nanoelectronic devices and promoting the development of related fields.

[0003] The force and electrical characteristics under stress are closely related to the formation and evolution of the internal structure of the material, but current research on this topic is mainly based on independent testing in a single mechanical or electrical mode, which cannot comprehensively understand the force and electrical characteristics under the coupled mode of mechanics and electricity. At the same time, the current in-situ test system mostly uses an open-loop capacitive sensing mechanism, which will cause the elastic energy in the sensor to accumulate continuously, so that when the sample experiences strain softening, the stability of the system is reduced, important material characteristics such as fracture and softening cannot be captured, and measurement errors are caused. At the same time, the above test system cannot output synchronous and transient data of force and electrical test data and time. Therefore, developing an in-situ automatic transient test chip that can simultaneously output mechanical and electrical characteristics and time is one of the problems to be solved in the field. SUMMARY

[0004] Technical problem: The technical problem to be solved by the application is to provide a test chip suitable for TEM / SEM electron microscopy to realize synchronous output of force and electrical parameters and a preparation method thereof.

[0005] Technical solution: The synchronous transient force-electric coupling test chip structure of the application comprises a device layer and a substrate, the device layer is fixed on the substrate through an anchor point, and the device layer is provided with a substrate hollow structure below; the device layer comprises a first supporting beam, a tensile thermal actuator, a strain capacitance sensor, a first lead beam, a first sample table, a second sample table, a second lead beam, a stress capacitance sensor, a second supporting beam and an electrostatic actuator; and all are located in the same plane; the tensile thermal actuator and the electrostatic actuator are both axisymmetric structures, and the symmetry axes are located on the same symmetry axis, the strain capacitance sensor and the stress capacitance sensor are both center-symmetric structures, the symmetry center is located on the symmetry axis, and the second sample table and the first sample table are also located on the symmetry axis;

[0006] The two ends of the first supporting beam, the first lead beam, the second lead beam and the second supporting beam are fixed on the substrate through anchor points respectively; the first supporting beam, the tensile thermal actuator, the strain capacitance sensor and the first lead beam are connected in sequence, the first supporting beam supports the tensile thermal actuator, the first lead beam supports the strain capacitance sensor, and the surface of the first lead beam is provided with an electrode lead; the first sample table is arranged at one end of the strain capacitance sensor; the first sample table moves along the symmetry axis with the strain capacitance sensor and the tensile thermal actuator;

[0007] The second lead beam and the second supporting beam are connected with the stress capacitance sensor and are located on the two sides of the stress capacitance sensor respectively, and are used for supporting the stress capacitance sensor; the electrode lead is arranged on the upper surface of the second lead beam, the stress capacitance sensor is connected with the electrostatic actuator, and the second sample table is arranged at one end of the stress capacitance sensor; the strain capacitance sensor and the stress capacitance sensor are both differential capacitance structures, which can effectively suppress the noise generated by the actuator and the environment and improve the test accuracy; the first sample table is adjacent to the second sample table; the electrode lead on the upper surface of the first lead beam and the electrode lead on the upper surface of the second lead beam constitute a four-probe test circuit.

[0008] The tensile and feedback execution load is provided by a tensile thermal actuator and an electrostatic actuator respectively, and a closed-loop feedback stress compensation control function is realized by the electrostatic actuator and a stress capacitor sensor, so that the accumulated elastic energy of the open-loop test and the electrostatic actuator system in the tensile is eliminated, the accuracy in the synchronous measurement is improved, and the synchronous measurement output is accurately completed. The electrostatic actuator realizes the execution feedback function, and the stress capacitor sensor realizes the stress sensing function; the tensile thermal actuator presents a displacement control mode in the working state, so that the whole system can capture transient mechanical characteristics such as stress relaxation and fracture. The active time judgment algorithm is designed in the closed-loop feedback stress compensation control part, so that the time intelligent judgment and control of the compensation process are realized, and the stress, strain and resistance signal synchronization and transient output of the sample to be measured are completed. The active time judgment algorithm refers to that the collector designs an active signal program to sequentially collect the change amounts of the strain capacitor, the resistance and the stress capacitor, when the change amount signal is obtained by the upper computer control program, it indicates that one collection is completed, then a feedback command is sent to the collector to perform the next round of collection. In this way, the synchronous test of different test parameters is controlled.

[0009] The test chip can be tested under in-situ TEM / SEM electron microscope conditions, and while automatically testing electrical parameters (conductivity), mechanical parameters (Young's modulus, stress, strain, fatigue, creep, etc.), the surface morphology or atomic fine structure of the sample to be measured can be analyzed in-situ by TEM / SEM electron microscope, and the micro-constructive relationship between the multiple physical parameters of the sample to be measured and the morphology or atomic fine structure of the material is obtained.

[0010] The test chip can be tested under non-in-situ conditions, and multiple physical field coupling tests can be realized by changing external test conditions (temperature, light, humidity, etc.).

[0011] Further, a connecting piece structure is designed between the tensile thermal actuator and the strain capacitor sensor, the connecting piece is made of a material with weak electrical conductivity and high mechanical strength such as high-resistance silicon or glass, so as to realize the mechanical connection and electrical isolation of the tensile thermal actuator and the strain capacitor sensor, and eliminate the influence of electromagnetic interference.

[0012] Further, a silicon nitride insulating layer is arranged on the first sample table and the second sample table for electrical insulation, and a four-probe test structure is arranged on the insulating layer.

[0013] Further, the tensile thermal actuator comprises a first mass block and a V-shaped beam; the first mass block is a rectangular plate, the first mass block is located on the central axis, and the V-shaped beam is symmetrical about the mass block; the V-shaped beam and the first support beam are connected with the first mass block respectively, both ends of the V-shaped beam are connected with V-shaped beam anchor points, and electrode pressure welding blocks are arranged on the surfaces of the V-shaped beam anchor points.

[0014] Further, the strain capacitance sensor comprises a second mass block, at least two groups of first movable comb teeth and first fixed comb teeth; the second mass block is located on the symmetry axis of the strain capacitance sensor, the first movable comb teeth are symmetrically fixed on the two sides of the second mass block, the first fixed comb teeth are all fixed on the substrate through anchor points, and are arranged in one-to-one correspondence with the first movable comb teeth, and each group of first movable comb teeth and first fixed comb teeth form a differential capacitance. The connecting piece is arranged between the first mass block and the second mass block, and is used for connecting the first mass block and the second mass block.

[0015] Further, the stress capacitance sensor comprises a third mass block, at least two groups of second movable comb teeth and second fixed comb teeth; the third mass block is located on the symmetry axis of the strain capacitance sensor, the second movable comb teeth are symmetrically fixed on the two sides of the third mass block, the second fixed comb teeth are all fixed on the substrate through anchor points, and are arranged in one-to-one correspondence with the second movable comb teeth, and each group of second movable comb teeth and second fixed comb teeth form a differential capacitance; the second lead beam and the second support beam are connected with the mass block respectively. The second sample table is arranged at one end of the third mass block, and the other end of the third mass block is connected with the electrostatic actuator.

[0016] The application further provides a preparation method of the synchronous transient force electric coupling test chip.

[0017] Step 1, growing silicon nitride on the upper and lower surfaces of the SOI silicon wafer to form an insulating layer and a back protective layer;

[0018] Step 2, patterning the insulating layer to realize electrode area opening;

[0019] Step 3, preparing Ti / Au as an electrode pressure welding block on the surface of the device;

[0020] Step 4, etching the device insulating layer and the single crystal silicon layer of the SOI silicon wafer to prepare a device layer;

[0021] Step 5, etching the back protective layer under the device layer, the substrate and the buried oxygen layer of the SOI silicon wafer; releasing the movable structure of the device layer, and completing the pre-preparation of the test chip structure.

[0022] Step 6, transferring and fixing the connecting piece between the tensile thermal actuator and the strain capacitance sensor by using a transfer technology.

[0023] Beneficial effects: compared with the prior art, the application has the following beneficial effects:

[0024] First, the test chip innovatively designs high-resistance silicon or glass as the connecting component, which has weak conductive performance but strong mechanical strength, instead of the integrated actuator and sensor (electrically unable to achieve isolation) always used in the conventional design of such devices, to achieve mechanical connection and electrical isolation between the tensile thermal actuator and the strain capacitance sensor, solve electromagnetic interference, and design a preparation method suitable for the structure of the application.

[0025] Second, the test chip has a closed-loop feedback stress compensation control component of the electrostatic actuator and the stress capacitance sensor, which eliminates the accumulated elastic energy of the open-loop test and the electrostatic actuator system when stretched, and improves the accuracy during synchronous measurement.

[0026] Third, the closed-loop feedback stress compensation control component designs an active time judgment algorithm to realize intelligent time judgment and control during the compensation process, and complete the stress, strain, and resistance signal synchronization and transient output of the sample to be tested. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 is a structure schematic diagram of the test chip in the embodiment of the application;

[0028] Figure 2 is a structure sectional view of the first step of the preparation method in the embodiment of the application;

[0029] Figure 3 is a structure sectional view of the second step of the preparation method in the embodiment of the application;

[0030] Figure 4 is a structure sectional view of the third step of the preparation method in the embodiment of the application;

[0031] Figure 5 is a structure sectional view of the fourth step of the preparation method in the embodiment of the application;

[0032] Figure 6 is a structure sectional view of the fifth step of the preparation method in the embodiment of the application;

[0033] Figure 7 is a structure sectional view of the sixth step of the preparation method in the embodiment of the application;

[0034] Figure 8 is a structure sectional view of the seventh step of the preparation method in the embodiment of the application;

[0035] Figure 9 is a closed-loop control scheme block diagram based on PID and information acquisition card in the embodiment of the application;

[0036] In the figure: Substrate 1, Silicon layer 11, Buried oxide layer 12, Silicon device layer 13, Insulating layer 401, Back protective layer 402, Bonding block 5, Substrate hollowing structure 6, First support beam 21, Second support beam 22, Tensile thermal actuator 3, First mass block 31, V-beam 32, Electrostatic actuator 4, First lead beam 51, Second lead beam 52, Strain capacitance sensor 9, First sample stage 91, Second mass block 92, First movable comb tooth 93, First fixed comb tooth 94, Stress capacitance sensor 7, Second sample stage 71, Third mass block 72, Second movable comb tooth 73, Second fixed comb tooth 74, Connecting component 8. Detailed Implementation

[0037] The technical solution of the present invention will now be described in detail with reference to the accompanying drawings.

[0038] like Figure 1 As shown, a synchronous transient force-electric coupling test chip of the present invention includes a device layer and a substrate 1 in its functional area. The device layer is fixed to the substrate 1 by anchor points. The substrate 1 is used to support the device layer, and a substrate hollowing structure 6 is provided below the device layer.

[0039] The device layer includes a first support beam 21, a tensile thermal actuator 3, a strain capacitive sensor 9, a first lead beam 51, a first sample stage 91, a second sample stage 71, a second lead beam 52, a stress capacitive sensor 7, a second support beam 22, an electrostatic actuator 4, and an electrode pressure welding block 5.

[0040] The tensile thermal actuator 3 and the electrostatic actuator 4 are axisymmetric structures, and their axes of symmetry are located on the same axis of symmetry. The strain capacitive sensor 9 and the stress capacitive sensor 7 are centrosymmetric structures, and their centers of symmetry are also located on the same axis of symmetry. The second sample stage 71 and the first sample stage 91 are also located on the axis of symmetry.

[0041] The first support beam 21, the first lead beam 51, the second lead beam 52, and the second support beam 22 are fixed to the substrate 1 at both ends by anchor points. The first support beam 21 is connected to one end of the tensile thermal actuator 3 to support the tensile thermal actuator 3. The other end of the tensile thermal actuator 3 is connected to the strain capacitive sensor 9 through the connector 8. The other end of the strain capacitive sensor 9 is connected to the first lead beam 51. The first lead beam 51 supports the strain capacitive sensor 9. The electrode leads are arranged along the surface of the first lead beam 51. The first sample stage 91 is arranged on the strain capacitive sensor 9. The first sample stage 91 moves along the axis of symmetry with the strain capacitive sensor 9 and the tensile thermal actuator 3.

[0042] The second lead beam 52 and the second support beam 22 are connected with the stress capacitance sensor 7 and are located on two sides of the stress capacitance sensor 7 respectively, and are used for supporting the stress capacitance sensor 7; an electrode lead is arranged on the second lead beam 52, and the electrode lead is arranged along the surface of the second lead beam 52; the stress capacitance sensor 7 is connected with the electrostatic actuator 4, one end of the stress capacitance sensor 7 is provided with a second sample table 71,

[0043] The first sample table 91 and the second sample table 71 are covered with a silicon nitride insulating layer for electrical insulation, and a four-probe test structure is arranged on the insulating layer; the electrode lead includes a first electrode lead, a second electrode lead, a third electrode lead and a fourth electrode lead, one end of the first electrode lead and the second electrode lead is located on the first sample table 91, and one end of the third electrode lead and the fourth electrode lead is located on the second sample table 71; the other end of the first electrode lead, the second electrode lead, the third electrode lead and the fourth electrode lead is connected with an external test circuit, and the electrode lead and the external test circuit constitute a four-probe test circuit.

[0044] The tensile thermal actuator 3 includes a first mass 31 and a V-shaped beam 32; the first mass 31 is located on the symmetry axis, the V-shaped beam 32 and the first support beam 21 are connected with the first mass 31 respectively, and both ends of the V-shaped beam 32 are connected with V-shaped beam anchor points, and an electrode pressure welding block 5 is arranged on the surface of the V-shaped beam anchor points, and is used for connecting with an external circuit;

[0045] The strain capacitance sensor 9 includes a second mass 92, at least two groups of first movable comb teeth 93 and first fixed comb teeth 94;

[0046] The second mass 92 is located on the symmetry axis, the first movable comb teeth 93 are symmetrically fixed on both sides of the second mass 92, the first fixed comb teeth 94 are fixed on the substrate 1 through anchor points, and are arranged in one-to-one correspondence with the first movable comb teeth 93, and each group of first movable comb teeth 93 and first fixed comb teeth 94 form a differential capacitance; a connecting piece 8 is arranged between the first mass 31 and the second mass 92, and is used for connecting the first mass 31 and the second mass 92, and the connecting piece 8 is processed by a focused ion beam (FIB) process; the electromagnetic interference of the tensile thermal actuator 3 on the strain capacitance sensor 9 can be avoided;

[0047] The stress capacitance sensor 7 includes a third mass 72, at least two groups of second movable comb teeth 73 and second fixed comb teeth 74;

[0048] The third mass 72 is located on the symmetry axis, the second movable comb teeth 73 are symmetrically fixed on the two sides of the third mass 72, the second fixed comb teeth 74 are fixed on the substrate 1 through anchor points, and are arranged in one-to-one correspondence with the second movable comb teeth 73, and each group of second movable comb teeth 73 and second fixed comb teeth 74 form a differential capacitor; the second lead beam 52 and the second support beam 22 are connected with the third mass respectively. The second sample table 71 is arranged at one end of the third mass 72, and the other end of the third mass 72 is connected with the electrostatic actuator 4.

[0049] The one end of the nanometer sample to be measured is placed on the first sample table 91 by using a transfer technology such as an FIB process, the other end is placed on the second sample table 71, and both ends are located on the four-probe test circuit, and the sample is placed along the central axis direction; the electrode welding block 5 is connected to the external test circuit by using a pressure welding technology, the voltage is applied to the two ends of the tensile thermal actuator 3, so as to provide uniaxial tensile load for the whole system, the capacitance of the strain capacitor sensor 9 changes, and the capacitance of the stress capacitor sensor 7 also changes, the upper computer is used for total program control, the capacitance change amount of the stress capacitor sensor 7 is collected through the information acquisition card and is converted into the voltage of the electrostatic actuator 4, the PID program is used to make the whole process closed-loop control, so as to keep the position of the stress capacitor sensor 7 unchanged, and finally the position of the second sample table 71 is kept unchanged.

[0050] Therefore, the test system stretches the sample in the displacement control mode, and avoids the accumulated elastic energy risk of the open-loop test system during stretching. The stress suffered by the sample can be obtained by the driving voltage and the structural rigidity of the tensile thermal actuator 3, and the sample strain can be obtained by the capacitance change amount of the strain sensor. Due to the existence of the insulating layer, the driving signal and the electrical test signal are isolated from each other, so that the mechanical and electrical characteristics will not be cross-talked in the test. By applying a small constant current to both ends of the sample, the potential difference of the inner electrode is measured by using a voltmeter, so that the four-probe electrical test of the sample is realized. Finally, the capacitance amount of the test chip strain capacitor sensor 9, the feedback voltage of the electrostatic actuator 4 and the potential difference of the sample in the four-probe electrical test are collected in real time through the information acquisition card, so that the electrical parameters (resistivity, potential difference) and the mechanical parameters (stress, strain) of the sample to be measured are associated with time, and the transient coupling relationship law analysis of the sample to be measured is realized.

[0051] A preparation method of a synchronous transient force-electric coupling test chip provided by the application is shown in the following steps. Figures 2-8 As shown in the figure, the preparation method comprises the following steps:

[0052] First step: growing 100-200nm silicon nitride on the upper and lower surfaces of an SOI silicon wafer to form an insulating layer 401 and a back protective layer 402; the SOI silicon wafer comprises a silicon layer 11, a buried oxygen layer 12 and a single crystal silicon layer 13

[0053] Second step: the insulating layer 401 is patterned by using photolithography and reactive ion etching process to realize electrode area opening and expose the single crystal silicon layer 13;

[0054] Third step: Ti / Au with a thickness of 50 / 250 nm is prepared on the surface of the device as an electrode pressure welding block 5 by using photolithography and electron beam evaporation process;

[0055] Fourth step: etching is performed on the device insulating layer 401 by using photolithography and reactive ion etching process;

[0056] Fifth step: the single crystal silicon layer 13 is etched by using the reactive ion etching process to prepare the first support beam 21, the first lead beam 51, the second lead beam 52, the tensile thermal actuator 3, the electrostatic actuator 4, the first sample table 91, the second sample table 71, the strain capacitance sensor 9 and the stress capacitance sensor 7 structure.

[0057] Sixth step: the back surface protective layer 402 under the movable structure of the device structure single crystal silicon layer 13 is etched by using photolithography and reactive ion etching process; the movable structure includes the first support beam 21, the tensile thermal actuator 3, the strain capacitance sensor 9, the first lead beam 51, the first sample table 91, the second sample table 71, the second lead beam 52, the stress capacitance sensor 7, the second support beam 22 and the electrostatic actuator 4.

[0058] Seventh step: the silicon layer 11 and the buried oxygen layer 12 under the movable structure are etched by using deep reactive ion etching technology to form a substrate hollow structure 6, release the movable structure of the device layer and complete the preparation of the test chip structure.

[0059] Eighth step: the connection material is transferred and fixed in the connecting component 308 by using FIB process processing and other transfer technologies to solve the electromagnetic interference of the tensile thermal actuator 3 on the strain capacitance sensor 9 and complete the preparation of the test chip structure. Figure 9 As shown in the closed-loop control scheme block diagram, when the sample is transferred to the sample table, the connection material is placed in the connecting component 308 by using FIB process processing and other transfer technologies and is reasonably placed, which can avoid the electromagnetic interference of the tensile thermal actuator 3 on the strain capacitance sensor 9. The voltage is applied at both ends of the tensile thermal actuator 3, the upper computer obtains the capacitance value change of the stress capacitance sensor 7 through the information acquisition card and converts it into a feedback voltage output to both ends of the electrostatic actuator 4, so that the test system performs stretching on the sample in displacement control mode to realize closed-loop control. The upper computer records the feedback voltage, and the information acquisition card is used to collect the capacitance change of the strain capacitance sensor 9 and the potential change of the four probes, and the stress, strain and resistance of the sample after calculation are associated with time and displayed and output to realize in-situ transient force and electricity test of the sample

[0060] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above specific embodiments, and the above specific embodiments and the description in the specification are only for further illustrating the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of the present application is defined by the claims and their equivalents.

Claims

1. A synchronous transient force-electric coupling test chip structure, characterized in that, It includes a device layer and a substrate. The device layer is fixed to the substrate by anchor points, and there is a substrate hollowing structure below the device layer. The device layer includes a first support beam, a tensile thermal actuator, a strain capacitive sensor, a first lead beam, a first sample stage, a second sample stage, a second lead beam, a stress capacitive sensor, a second support beam, and an electrostatic actuator; all of which are located in the same plane. Both the tensile thermal actuator and the electrostatic actuator are axisymmetric structures, and their axes of symmetry are located on the same axis of symmetry. Both the strain capacitive sensor and the stress capacitive sensor are centrosymmetric structures, with their centers of symmetry located on the same axis of symmetry. The second sample stage and the first sample stage are also located on the axis of symmetry. The first support beam, the first lead beam, the second lead beam, and the second support beam are fixed to the substrate at both ends by anchor points. The first support beam, the tensile thermal actuator, the strain capacitive sensor, and the first lead beam are connected in sequence. The first support beam supports the tensile thermal actuator, and the first lead beam supports the strain capacitive sensor. Electrode leads are provided on the surface of the first lead beam. The first sample stage is located at one end of the strain capacitive sensor. The first sample stage moves along the axis of symmetry with the strain capacitive sensor and the tensile thermal actuator. The second lead beam and the second support beam are connected to the stress capacitive sensor and are located on both sides of the stress capacitive sensor to support it. Electrode leads are provided on the upper surface of the second lead beam. The stress capacitive sensor is connected to the electrostatic actuator. A second sample stage is provided at one end of the stress capacitive sensor. The first sample stage is adjacent to the second sample stage; The electrode leads on the upper surface of the first lead beam and the electrode leads on the upper surface of the second lead beam constitute a four-probe test circuit.

2. The synchronous transient force-electric coupling test chip structure according to claim 1, characterized in that, A connecting structure is designed between the tensile thermal actuator and the strain capacitive sensor, and the connecting component is made of high-resistivity silicon or glass.

3. The synchronous transient force-electric coupling test chip structure according to claim 1, characterized in that, The first and second sample stages are covered with a silicon nitride insulating layer for electrical insulation, and the four-probe test structure is arranged on the insulating layer.

4. The synchronous transient force-electric coupling test chip structure according to claim 1, characterized in that, The tensile thermal actuator includes a first mass block and a V-beam; The first mass block is located on the axis of symmetry, and the V-shaped beam is symmetrical about the first mass block; The V-shaped beam and the first support beam are respectively connected to the first mass block. The two ends of the V-shaped beam are connected to V-shaped beam anchor points, and electrode pressure welding blocks are provided on the surface of the V-shaped beam anchor points.

5. The synchronous transient force-electric coupling test chip structure according to claim 1 or 4, characterized in that, The strain capacitive sensor includes a second mass block, at least two sets of first movable comb teeth, and first fixed comb teeth; The second mass block is located on the axis of symmetry. The first movable comb teeth are symmetrically fixed on both sides of the second mass block. The first fixed comb teeth are all fixed on the substrate through anchor points and are set in a one-to-one correspondence with the first movable comb teeth. Each group of first movable comb teeth and first fixed comb teeth forms a differential capacitor.

6. The synchronous transient force-electric coupling test chip structure according to claim 5, characterized in that, The connector is disposed between the first mass block and the second mass block, and is used to connect the first mass block and the second mass block.

7. The synchronous transient force-electric coupling test chip structure according to claim 1, characterized in that, The stress-capacitance sensor includes a third mass block, at least two sets of second movable comb teeth, and second fixed comb teeth. The third mass block is located on the axis of symmetry. The second movable comb teeth are symmetrically fixed on both sides of the third mass block. The second fixed comb teeth are all fixed to the substrate by anchor points and are set in a one-to-one correspondence with the second movable comb teeth. Each group of second movable comb teeth and second fixed comb teeth forms a differential capacitor. The second lead beam and the second support beam are respectively connected to the third mass block; The second sample stage is located at one end of the third mass block, and the other end of the third mass block is connected to an electrostatic actuator.

8. The synchronous transient force-electric coupling test chip structure according to claim 1, characterized in that, An active time-based judgment algorithm is designed to sequentially acquire changes in strain capacitance, resistance, and stress capacitance. When the host computer control program receives the change signal, it indicates that one acquisition is complete, and then sends a feedback command to the acquisition unit to start the next round of acquisition.

9. A method for fabricating a synchronous transient force-electric coupling test chip, characterized in that, The method is based on the test chip as described in claim 2 and includes the following steps: Step 1: Silicon nitride is grown on the upper and lower surfaces of the SOI silicon wafer to form an insulating layer and a back protective layer; Step 2: Pattern the insulating layer to create openings in the electrode area; Step 3: Prepare Ti / Au bonding pads as electrodes on the device surface; Step 4: Etch the insulating layer of the device and the single-crystal silicon layer of the SOI silicon wafer to prepare the device layer; Step 5: Etch the back protective layer below the device layer, as well as the substrate and buried oxide layer of the SOI silicon wafer; release the movable structure of the device layer to complete the pre-fabrication of the test chip structure; Step 6: Use transfer technology to transfer and fix the connector between the tensile thermal actuator and the strain capacitive sensor.

10. The method for fabricating a synchronous transient force-electric coupling test chip according to claim 9, characterized in that, The thickness of the silicon nitride grown in step 1 is 100-200 nm, and the thickness of the Ti / Au in step 3 is 50 / 250 nm.

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