Integral thin-film pressure sensor with piezoelectric shape determination and preparation method

Abstract

An integrally formed thin-film pressure sensor with a determined piezoelectric shape and a preparation method thereof according to the present invention include a packaging layer, an electrode layer, and a functional layer; the functional layer is a thin-film structure and includes a piezoelectric region and an insulating region, wherein the piezoelectric shape of the piezoelectric region is determined; the electrode layer includes an upper electrode and a lower electrode, and the upper electrode and the lower electrode are respectively disposed on the upper and lower sides of the piezoelectric region to lead out the electrical signal of the piezoelectric region; the upper and lower electrodes do not overlap in the direction perpendicular to the thickness direction; the packaging layer is wrapped outside the electrode layer; the shape of the piezoelectric region includes regular figures and irregular figures, wherein the regular figures include circles, rectangles, triangles, ellipses, polygons, and crosses; the irregular figures include tadpole shapes, paper-cut shapes, broken-line shapes, S shapes, figure-eight shapes, concave shapes, and rings. Due to the determined piezoelectric shape of the present invention, the output electrical signal is stable with the change of pressure, the signal is strong and not affected by the surface curvature, the preparation process is simple, and it has a good application prospect in surface measurement.

Description

Technical Field

[0001] The present invention relates to the field of sensor technology, and in particular to an integral thin film pressure sensor with a defined piezoelectric shape and a preparation method thereof. Background Art

[0002] Piezoelectric sensors have fast response and high sensitivity, making them a good choice for measuring dynamic pressure. Touch and collision in daily life are short-term pressures, which fall within the scope of dynamic pressure measurement. Considering that most objects in life have a certain curvature on their surfaces, thin-film sensors need to have high measurement accuracy on curved surfaces. Only in this way can the measurement requirements of artificial intelligence and machine perception be met.

[0003] Application method of pressure sensor: first know the pressure value within a certain range, then load the pressure of the determined value X1 onto the sensor to obtain a certain electrical signal Y1, which is called the calibrated data point. Load multiple times to obtain X2, Y2; X3, Y3; X4, Y4; X5, Y5. Plot the above data points on the XY axis to establish the mathematical relationship between X and Y. This process is called calibration. In the application, use this relationship to correspond to the pressure value under a certain electrical signal.

[0004] Piezoelectric film: The initial film has no piezoelectric properties, and then needs to be polarized by a certain method (multiple stretching, or high pressure, or high temperature), and the polarized film has piezoelectric properties. Due to technical limitations, current commercial films are all polarized on a large surface. The important innovation of this invention is local polarization, and the shape or area can be accurately controlled.

[0005] Piezoelectric film pressure sensor is a thin film pressure sensor made of piezoelectric film material. Due to its wide frequency response and high sensitivity, it has a very wide range of applications in dynamic pressure measurement. The main functional unit of the piezoelectric film pressure sensor (piezoelectric unit) is the source of the sensor's electrical signal and controls the sensor's electrical signal output capability. Most of the current piezoelectric film pressure sensors are cut from a large-area piezoelectric film and then packaged. When this type of sensor is compressed (such as when pressed by a finger), the pressure area is uncertain, so the consistency of the pressure measurement result is poor. Some of the existing technologies mention locally polarized piezoelectric film sensors, which use conductive silver glue as electrodes and only control the area of the electrodes, but do not pay attention to the polarization effect, that is, this method does not obtain a piezoelectric film with a determined piezoelectric area or piezoelectric shape. Therefore, the piezoelectric film sensor prepared by polarization of conductive silver glue has a large performance difference and cannot be truly used for pressure measurement.

[0006] The signal of the thin-film piezoelectric material is weak. Therefore, to obtain a strong enough signal, a large pressure-receiving area is required. However, a large pressure-receiving area is easily affected by the curved surface on the curved surface, resulting in inaccurate signal measurement. Therefore, these two aspects are contradictory.

[0007] 1. Existing cutting-type piezoelectric sensors

[0008] In the existing technology, the required area is cut out from a large-area piezoelectric thin film and then repackaged for use. For the sensors with this structure, the flatness is poor, and there is a material mismatch between the cut material and the packaging material, which easily causes stress concentration in the edge area of the cut structure. The use on the curved surface of the sensor further exacerbates this stress concentration effect, resulting in a large measurement error of the sensor and poor device reliability, and it is easy to be damaged.

[0009] 2. Existing local polarization sensors

[0010] For the sensor structure prepared by the local polarization method in the existing technology, the polarization area and shape are not clear, and it cannot meet the requirements of curved surface use under the condition of large-area polarization. The signal interference is too large during bending, and the measurement error is large; when the polarization area is small, the signal is very weak, and due to the uncertainty of the polarization area, the signal is unstable, and the pressure received cannot be accurately measured, and the measurement accuracy is insufficient. Summary of the Invention

[0011] A piezoelectric shape-determined integral thin-film pressure sensor and a preparation method proposed by the present invention can at least solve one of the above technical problems.

[0012] To achieve the above object, the present invention adopts the following technical solutions:

[0013] A piezoelectric shape-determined integral thin-film pressure sensor includes a packaging layer, an electrode layer, and a functional layer;

[0014] The functional layer is a thin-film structure, including a piezoelectric region and an insulating region, wherein the piezoelectric shape of the piezoelectric region is determined;

[0015] The electrode layer includes an upper electrode and a lower electrode. The upper electrode and the lower electrode are respectively arranged on the upper and lower sides of the piezoelectric region to lead out the electrical signal of the piezoelectric region; the upper and lower electrodes do not overlap in the direction perpendicular to the thickness direction;

[0016] The packaging layer is wrapped outside the electrode layer;

[0017] The shape of the piezoelectric region includes regular figures and irregular figures, wherein the regular figures include circles, rectangles, triangles, ellipses, polygons, and crosses;

[0018] The irregular figures include tadpole shapes, paper-cut shapes, broken line shapes, S shapes, square frame shapes, concave shapes, and ring shapes.

[0019] Further, the piezoelectric regions are set to be N, where N is a natural number greater than or equal to 1; the piezoelectric regions are on the same thin film;

[0020] The N piezoelectric regions are arranged in an array.

[0021] Further, the N piezoelectric regions are connected in parallel.

[0022] Further, the piezoelectric regions and the insulating regions are different parts of a complete thin film.

[0023] On the other hand, the present invention also discloses a preparation method of an integral thin film pressure sensor, including the following steps:

[0024] S10. Prepare metal electrodes on both sides;

[0025] S20. Based on the prepared metal electrodes on both sides, perform polarization on the target area to polarize a piezoelectric thin film with a determined piezoelectric shape;

[0026] S30. Etch the above metal electrodes, and only retain the thin film with the set polarized shape;

[0027] S40. Prepare lead electrodes of the piezoelectric thin film by magnetron sputtering method for the output of electrical signals, or prepare them by thermal evaporation method;

[0028] S50. On both sides of the lead electrodes, encapsulate the structure with an insulating material.

[0029] Further, the step S10 specifically includes:

[0030] S11. Prepare a mask plate with round holes;

[0031] S12. Align the round holes of the two mask plates up and down, and place the piezoelectric thin film in the middle of the mask plates;

[0032] S13. Prepare electrodes on both sides by magnetron sputtering method.

[0033] Further, the step S20 specifically includes:

[0034] S21. Place the thin film with electrodes prepared on a polarimeter;

[0035] S22. The polarization indenter is circular, and align it with the electrode positions on the thin film;

[0036] S23. First apply a positive high voltage of 2 kV for 30 s; then apply a negative high voltage of 2 kV for 30 s; then apply a positive high voltage of 6 kV for 1200 s;

[0037] S24. After polarization, measure the piezoelectric properties at the edge of the electrode to determine the polarized diameter or range at the edge of the electrode.

[0038] Furthermore, step S30 specifically includes:

[0039] S31. Prepare a metal ring according to the diameter of the polarized range at the edge, place the upper and lower rings on both sides of the thin film, and apply a negative polarization high voltage of 2V to balance the polarized part at the edge.

[0040] S32. If the polarization performance at the edge does not meet the requirements, repeat the above operation multiple times, adjust the reverse polarization voltage and time, and finally make the piezoelectric performance at the edge of the polarization electrode meet the set requirements.

[0041] S34. Remove the thin film after polarization.

[0042] Furthermore, the specific steps of step S40 are as follows.

[0043] S41. Prepare a mask plate with a tail.

[0044] S42. Align the upper and lower round holes of two mask plates, place the piezoelectric thin film with a determined piezoelectric shape in the middle of the mask plates, and align the circular area with the polarized area.

[0045] S43. Use the magnetron sputtering method to prepare two-sided lead-out electrodes.

[0046] Furthermore, the piezoelectric shape determined in step S42 is circular, rectangular, triangular, elliptical, polygonal, and cross-shaped.

[0047] Irregular figures include tadpole-shaped, paper-cut-shaped, broken-line-shaped, S-shaped, square-shaped, concave-shaped, and ring-shaped.

[0048] As can be seen from the above technical solutions, the present invention proposes a piezoelectric thin film pressure sensor with a determined piezoelectric shape. Since its piezoelectric shape is determined, when preparing the sensor, the consistency of the electrical signal output of the sensor is better, and consistent measurement results can be obtained when used for pressure measurement.

[0049] A novel piezoelectric sensing structure of the present invention has a strong signal and is not affected by the surface curvature due to the determined piezoelectric shape, and the preparation process is simple, so it has a very broad application prospect in surface measurement.

[0050] Specifically, the advantages of the present invention are as follows:

[0051] 1. In terms of process, the positive and negative voltage polarization method is adopted to eliminate the unstable phase in the target polarization area and improve the polarization performance of the target area.

[0052] 2. For the edge corona area of the target polarization area, a circular ring-shaped polarization head is used, and the multiple reverse voltage polarization method is adopted to eliminate the polarization effect of the edge corona area, enhance the boundary of the target polarization area, and determine the shape of the target polarization area.

[0053] 3. The local polarization structure design on the whole film improves the flatness and service life of the sensor;

[0054] 4. The target polarization region with a determined shape makes the output electrical signal of the sensor more stable. The pressure-electric signal relationship established based on this output signal can provide a more accurate basis for pressure measurement.

[0055] 5. Polarization regions with various different shapes greatly expand the application scenarios of the sensor, improving the sensitivity and accuracy of the sensor.

[0056] 6. The design of the curved surface long-strip polarization region reduces the influence of the curved surface on the piezoelectric signal of the sensor, improving the attachment ability and measurement accuracy of the sensor on flexible and curved surface structures.

[0057] 7. The non-overlapping design of the electrodes on the vertical structure eliminates the parasitic capacitance between the upper and lower electrodes, improving the measurement stability and accuracy of the piezoelectric sensor.

[0058] 8. The parallel structure between multiple piezoelectric regions improves the stability of the piezoelectric signal of the sensor, increases the signal-to-noise ratio of the sensor, and improves the measurement reliability of the sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 is a schematic diagram of the module structure of the present invention;

[0060] Figure 2 is a schematic diagram of the structure of an embodiment of the present invention;

[0061] Figure 3 is a schematic diagram of several piezoelectric region shapes and their corresponding arrays in an embodiment of the present invention;

[0062] Figure 4 is a schematic diagram of preparing electrodes by a magnetron sputtering method in an embodiment of the present invention;

[0063] Figure 5 is a schematic diagram of target region polarization in an embodiment of the present invention;

[0064] Figure 6 is a schematic diagram of etching metal electrodes in an embodiment of the present invention;

[0065] Figure 7 is a schematic diagram of leading out electrodes for preparing a piezoelectric thin film in an embodiment of the present invention;

[0066] Figure 8 is a schematic diagram of packaging in an embodiment of the present invention;

[0067] Figure 9 is a single polarization effect diagram of the thin film in an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0068] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention.

[0069] The piezoelectric shape-determined integrated thin-film pressure sensor described in this embodiment has a structure as Figure 1 shown, including a packaging layer, an electrode layer, and a functional layer; among them, the functional layer is a thin-film structure, including a piezoelectric region and an insulating region, and the piezoelectric shape in the piezoelectric region is determined;

[0070] The electrode layer includes an upper electrode and a lower electrode. The upper electrode and the lower electrode are respectively arranged on the upper and lower sides of the piezoelectric region to lead out the electrical signals of the piezoelectric region; the upper and lower electrodes do not overlap in the direction perpendicular to the thickness direction;

[0071] The packaging layer is wrapped outside the electrode layer;

[0072] The shape of the piezoelectric region includes regular figures and irregular figures. Among them, regular figures include circles, rectangles, triangles, ellipses, polygons, and crosses; irregular figures include tadpole shapes, paper-cut shapes, broken-line shapes, S shapes, square-within-a-square shapes, concave shapes, and ring shapes. In the same product, the shapes of the piezoelectric units used are repeated or change according to a certain rule, which is the shape determination.

[0073] Among them, the piezoelectric region is set to N, and N is a natural number greater than or equal to 1;

[0074] The N piezoelectric regions are arranged in an array, and the N piezoelectric regions are connected in parallel; it is not completely necessary to connect in parallel here. Electrodes can be made separately to output individual electrical signals, that is, M completely independent sensors;

[0075] Two large-area electrodes can also be prepared on both sides of the thin film. A single electrode covers M≥1 polarization regions, and a parallel structure is formed among the M polarization regions. This structure can improve the stability of the piezoelectric signal and reduce the interference of the sensor.

[0076] As Figure 3 shown, the embodiments of the present invention list several current situations of the piezoelectric region and their corresponding arrays.

[0077] The piezoelectric region and the insulating region are different parts on a complete thin film. The piezoelectric region is made on the thin film by local polarization to ensure the structural integrity and flatness of the sensor.

[0078] The misalignment design of the upper and lower lead electrodes of the piezoelectric sensor in the external area of the piezoelectric unit is the structure protected by the present invention. That is, the non-overlapping part of the upper and lower electrodes outside the piezoelectric area when viewed from the up and down directions. The upper and lower electrodes are arranged in a misaligned manner in the direction perpendicular to the thickness, that is, outside the piezoelectric area, the upper and lower electrodes are not staggered in the direction perpendicular to the thickness of the sensor. This structural design reduces the parasitic capacitance of the piezoelectric sensor and makes the measurement more accurate.

[0079] In a specific embodiment, the electrode layer can be attached to the encapsulation layer or the functional layer, such as Figure 2 As shown, in the example given in this embodiment, the upper electrode and the lower electrode are respectively attached to the encapsulation layer.

[0080] Specifically, the piezoelectric area on the piezoelectric functional layer is a parallel strip structure, and the length direction of this structure is arranged perpendicular to the curvature direction of the measured surface, overcoming the influence of surface bending on the piezoelectric signal;

[0081] In the length direction, the length of the piezoelectric unit is designed to be related to the measured object and is less than the length of the measured object; in the width direction, the width of a single piezoelectric unit is designed to be less than the curvature diameter of the measured curved surface. Reducing the influence of bending on the piezoelectric signal;

[0082] When applied on a curved surface, the width dimension d1 of the polarization unit and the curvature diameter φ of the measured curved surface should ensure that d1 ≤ 1 / 2φ. When the curved surface is bent, the bending of the curved surface interferes with the electrical signal of the polarization unit.

[0083] When in use, for the sensor array structure of multiple piezoelectric units, the size, shape, and distance between adjacent piezoelectric units are not restricted, and the arrangement quantity is determined according to actual requirements; the shape of the piezoelectric area of a single piezoelectric unit on the piezoelectric functional layer is determined. Measuring the length and width of the piezoelectric area with the piezoelectric coefficient of the piezoelectric material, there is a boundary with a piezoelectric coefficient of 0 between adjacent piezoelectric units, and the distance between the point with the maximum piezoelectric coefficient and the point with a piezoelectric coefficient of 0 is less than 3 times the max (the maximum distance between the maximum piezoelectric values);

[0084] If the curvature of the measured surface is infinite, that is, the measured surface is a plane, then the length and width directions are not distinguished; in terms of quantity, single unit or multiple units can be used for measurement.

[0085] The upper and lower electrodes lead out the piezoelectric signal. The electrode structure described in the present invention connects the piezoelectric areas of the surface where it is located, enhancing the signal stability of the piezoelectric sensor;

[0086] Generally speaking, the piezoelectric area of the present invention is circular, rectangular, triangular, elliptical, polygonal, cross-shaped, as well as tadpole-shaped, paper-cut-shaped, broken-line-shaped, S-shaped, square-shaped / concave-shaped and annular.

[0087] The distance between the maximum value of the piezoelectric coefficient of the above structure and the piezoelectric coefficient 0 is less than 3 times of max (the farthest distance of the upper electrode endpoints). As Figure 9 shown: the diameter of the outer ring is less than 3 times the diameter of the inner circle;

[0088] Using the structure in the above embodiment of the invention, a sensor structure with any shape and a determined area can be made on a single thin film.

[0089] Using the structure in the above invention, multiple array-type sensor structures with any shape and a determined area can also be made on a single thin film.

[0090] The following is the specific preparation process of the embodiment of the present invention, including,

[0091] S10. Prepare metal electrodes on both sides;

[0092] S20. Based on the prepared metal electrodes on both sides, perform polarization on the target area to polarize a piezoelectric thin film with a determined piezoelectric shape;

[0093] S30. Etch the above metal electrodes, and only retain the thin film with the set polarized shape;

[0094] S40. Prepare lead-out electrodes for the piezoelectric thin film by magnetron sputtering method for the output of electrical signals;

[0095] S50. On both sides of the lead-out electrodes, encapsulate the structure with an insulating material.

[0096] The following is a specific description:

[0097] Among them, S10. Prepare metal electrodes on both sides; specifically includes the following steps,

[0098] S11. Prepare a mask plate with round holes;

[0099] S12. Align the round holes of the two mask plates up and down, and place the piezoelectric thin film in the middle of the mask plates;

[0100] S13. Prepare electrodes on both sides by magnetron sputtering method, as Figure 4 shown;

[0101] Specifically, S20. Based on the prepared metal electrodes on both sides, perform polarization on the target area to polarize a piezoelectric thin film with a determined piezoelectric shape, as Figure 5 shown, specifically includes the following steps,

[0102] S21. Place the thin film with circular electrodes prepared on the polarizer,

[0103] S22. The polarization indenter is circular, and align it with the electrode position on the thin film;

[0104] S23. First, apply a positive high voltage of 2 kV for 30 s; then apply a negative high voltage of 2 kV for 30 s; then apply a positive high voltage of 6 kV for 1200 s.

[0105] S24. After polarization, measure the piezoelectric properties at the edge of the electrode. The polarization effect at the edge is much worse than that at the electrode, and determine the diameter or range of the polarized area at the edge of the electrode.

[0106] Specifically, S30. Etch the above-mentioned metal electrode, only leaving the thin film with a set polarization shape, as Figure 6 shown. The specific steps are as follows:

[0107] S31. Prepare a metal ring according to the diameter of the polarized range at the edge. Place the upper and lower rings on both sides of the thin film, and apply a negative polarization high voltage of 2 v to balance the polarized part at the edge; since the negative polarization voltage is much lower than the positive polarization voltage and the time is shorter, it has almost no effect on the positive polarization effect. Using the above method can make the polarization profile of the thin film clearer and the shape more regular.

[0108] S32. Using the method described in the second step, if the polarization performance at the edge is still relatively obvious, the above operation can be repeated multiple times, adjusting the reverse polarization voltage and time, and finally achieving the purpose of very small piezoelectric performance at the edge of the polarized electrode.

[0109] S33. Remove the thin film after polarization.

[0110] Note: The above-mentioned shape is clear and the contour is clear. Taking the range where the piezoelectric performance is reduced to 0 as the standard, in terms of size, the distance from the edge of the circular electrode to where the piezoelectric performance drops to 0 needs to be controlled within 10 times the polarization diameter.

[0111] The above-mentioned shape can be circular, rectangular, triangular, elliptical, polygonal, cross-shaped, as well as irregular shapes including tadpole-shaped, paper-cut-shaped, broken-line-shaped, S-shaped, square-shaped, and concave-shaped, etc. When preparing, corresponding polarization heads and electrode structures of corresponding shapes need to be used. Using this method, the shape of the polarized area is determined. As a product, a piezoelectric structure with a determined shape can obtain a stable piezoelectric signal for accurate measurement.

[0112] S40. Use the magnetron sputtering method to prepare the lead-out electrode of the piezoelectric thin film for the output of electrical signals; as Figure 7 shown. Specifically, it includes the following steps:

[0113] S41. Prepare a mask plate with a tail.

[0114] S42. Align the upper and lower round holes of 2 mask plates. Place the piezoelectric thin film with a determined piezoelectric shape in the middle of the mask plate, and align the circular area with the polarized area.

[0115] S43. Prepare two-sided lead-out electrodes using the magnetron sputtering method;

[0116] Note: The purpose of the lead-out electrode is to lead out the electrical signal, so conductive electrodes of any shape and any material can be used.

[0117] S50. On both sides of the lead-out electrode, encapsulate the structure with an insulating material, such as Figure 8 as shown.

[0118] As can be seen from the above, the advantages of the embodiments of the present invention are as follows:

[0119] 1. In terms of process, the positive and negative voltage polarization method is adopted to eliminate the unstable phases in the target polarization region and improve the polarization performance of the target region.

[0120] 2. For the edge corona region of the target polarization region, use a circular polarization head and adopt the multiple reverse voltage polarization method to eliminate the polarization effect in the edge corona region, enhance the boundary of the target polarization region, and determine the shape of the target polarization region.

[0121] 3. The local polarization structure design on the entire film improves the flatness and service life of the sensor;

[0122] 4. The target polarization region with a determined shape makes the output electrical signal of the sensor more stable. Based on the pressure-electrical signal relationship established by this output signal, it can provide a more accurate basis for pressure measurement.

[0123] 5. Polarization regions of various different shapes greatly expand the application scenarios of the sensor, improving the sensitivity and accuracy of the sensor.

[0124] 6. The design of the curved strip-shaped polarization region reduces the influence of the curve on the piezoelectric signal of the sensor and improves the attachment ability and measurement accuracy of the sensor on flexible and curved structures.

[0125] 7. The non-overlapping design of the electrodes on the vertical structure eliminates the parasitic capacitance between the upper and lower electrodes and improves the measurement stability and accuracy of the piezoelectric sensor.

[0126] 8. The parallel structure between multiple piezoelectric regions improves the stability of the piezoelectric signal of the sensor, increases the signal-to-noise ratio of the sensor, and improves the measurement reliability of the sensor.

[0127] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A preparation method of an integral thin-film pressure sensor, characterized in that, Including the following steps, S10. Prepare two-sided metal electrodes on both sides of the piezoelectric thin film; S20. Based on the prepared two-sided metal electrodes, perform target area polarization to polarize a piezoelectric thin film with a determined piezoelectric shape; specifically including: S21. Place the film with electrodes prepared on a polarizer, S22. The polarization indenter is circular and aligns with the electrode positions on the film; S23. First apply a positive high voltage of 2 kV for 30 s; then apply a negative high voltage of 2 kV for 30 s; then apply a positive high voltage of 6 kV for 1200 s; S24. After polarization, measure the piezoelectric properties at the edge of the electrode to determine the polarized diameter or range at the edge of the electrode; S30. Etch the above metal electrodes and only retain the film with a set polarized shape; specifically including: S31. Prepare metal rings according to the polarized range diameter at the edge, place the upper and lower rings on both sides of the film, and apply a negative polarization voltage to balance the polarized part at the edge; S32. If the polarization performance at the edge does not meet the requirements, repeat the above step S31 multiple times, adjust the negative polarization voltage and time, and finally achieve that the piezoelectric performance at the edge of the polarized electrode meets the set requirements; S40. Prepare the lead electrodes of the piezoelectric thin film by magnetron sputtering method for the output of electrical signals; or prepare them by thermal evaporation method; S50. On both sides of the lead electrodes, encapsulate the thin film pressure sensor with an insulating material.

2. The preparation method of an integral thin-film pressure sensor according to claim 1, characterized in that, The step S10 specifically includes: S11. Prepare a mask plate with round holes; S12. Align the round holes of the two mask plates up and down, and place the piezoelectric thin film in the middle of the mask plates; S13. Prepare two-sided electrodes by magnetron sputtering method.

3. The preparation method of an integral thin-film pressure sensor according to claim 1, wherein, After polarization in step S32, remove the film.

4. The preparation method of an integral thin-film pressure sensor according to claim 1, characterized in that, The specific steps of the step S40 are as follows, S41. Prepare a mask plate with a tail; S42. Align the round holes of the two mask plates up and down, place the piezoelectric thin film with a determined piezoelectric shape in the middle of the mask plates, and align the circular area with the polarized area; S43. Prepare two-sided lead electrodes by magnetron sputtering method.

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