Piezoelectric driving miniature electric field sensor

Abstract

The utility model discloses a piezoelectric driving miniature electric field sensor, which comprises two groups of oppositely arranged substrates, an induction electrode layer and a driving structure, the induction electrode layer cantilevers are arranged on the substrate, the free ends of the induction electrode layers are provided with comb tooth structures, and the comb tooth structures of the two induction electrode layers are mutually inserted to form a sensor sensitive structure; the driving structure comprises a lower driving electrode layer, a piezoelectric material layer and an upper driving electrode layer which are arranged in sequence; when driving voltage is applied between the lower driving electrode layer and the upper driving electrode layer, the piezoelectric material layer enables the comb tooth structure at the free end of one group of sensing electrode layers to vibrate up and down relative to the comb tooth structure at the free end of the other group of sensing electrode layers, so that current intensity in direct proportion to the intensity of an electric field to be measured is generated between the two groups of sensing electrodes. And outputting the current signal. The utility model discloses a piezoelectric driving miniature electric field sensor, which has the advantages of simple structure and process, high yield, large inductive charge quantity, high sensitivity and the like.

Description

Technical Field

[0001] The utility model relates to the field of sensors and micro-electromechanical system technology, in particular to a piezoelectric driven micro electric field sensor. Background Art

[0002] Electric field measurement has a wide range of applications in meteorological research, aerospace, power systems, etc. Electric field sensors are used to measure the electric field and obtain effective information to ensure the launch safety of rockets, satellites and other aircraft, and to avoid personal injury and property loss in meteorology, aerospace, power grid, industrial production and other fields.

[0003] Micro electric field sensors based on micromachining technology have obvious advantages: small mass, more conducive to measuring high altitude or outer space; small size, can be used to measure the details of electric field distribution; in addition, it is relatively easy to integrate micro electric field sensors with other sensors, such as temperature sensors, pressure sensors, humidity sensors, etc. Therefore, micro electric field sensors based on micromachining technology have broad application prospects.

[0004] At present, the driving modes of micro MEMS electric field sensors mainly include electrostatic drive, piezoelectric drive, electromagnetic drive and thermal drive. The electrostatically driven micro electric field sensor has a high driving voltage, which results in large power consumption and temperature drift. The thermally driven micro electrostatic field sensor has a high driving voltage. If it works for a long time, the temperature characteristics of the driving structure material will change, resulting in unstable driving displacement. The electromagnetic drive method will bring strong electromagnetic interference, affect the sensing structure to measure the electric field, and increase the detection circuit noise.

[0005] Tao Hu et al. provided a MEMS electric field sensor using a piezoelectric ceramic strip as a driving structure ("Design and manufacture of a micro electric field sensor based on micromachining technology", 639-642, 2006, 29(3), Electronic Devices. In the MEMS electric field sensor structure, two groups of comb-tooth electrodes relative to each other are connected to the piezoelectric ceramic strip by an adhesive. When a pair of driving voltages of the same frequency with the same amplitude and opposite polarity are applied to the two groups of piezoelectric ceramics, the two groups of electrodes vibrate under the drive of the piezoelectric ceramics. When one group of electrodes moves upward, the other group of electrodes moves downward. The comb-tooth electrodes moving to the upper side induce more charges, while the comb-tooth electrodes moving to the lower side induce less charges. Therefore, when the two groups of comb-tooth electrodes vibrate alternately, the number of surface charges will change periodically, thereby forming an alternating differential current signal proportional to the electric field strength applied to the sensing electrode.

[0006] However, in the above-mentioned MEMS electric field sensor, the piezoelectric ceramic strips are connected by an adhesive, the manufacturing precision is inaccurate, and it is not suitable for mass production.

[0007] Chinese invention patent application number: 201310491424.8, patent name: piezoelectric cantilever beam type micro electric field sensor; discloses a piezoelectric cantilever beam type micro electric field sensor, the sensor includes a substrate and a sensor sensitive structure formed by a multi-layer structural layer, the sensor sensitive structure is fixed on the base and forms a cantilever beam structure, and a comb structure is formed at the free end of the sensor sensitive structure. The structure disclosed in the patent has the following shortcomings: 1. Since the sensor comb structure covers all structural layers, the sensor structure and preparation process are complicated, and the yield is low; 2. The induction charge of the induction electrode layer is small, and the induction current is small, which leads to low induction sensitivity. Utility Model Content

[0008] In view of the above problems, the utility model proposes a piezoelectric driven micro electric field sensor.

[0009] The technical means adopted by the utility model are as follows:

[0010] A piezoelectric driven micro electric field sensor comprises two groups of substrates arranged opposite to each other, a sensing electrode layer arranged on the substrate, and a driving structure for driving the sensing electrode layer to vibrate;

[0011] One end of the sensing electrode layer is arranged on the substrate, and the other end is suspended in the air to form a cantilever beam structure. The free end of the sensing electrode layer is provided with a comb tooth structure. The comb tooth structures of two groups of sensing electrode layers are arranged opposite to each other and interlaced with each other to form a sensor sensitive structure.

[0012] The driving structure comprises a lower driving electrode layer, a piezoelectric material layer and an upper driving electrode layer which are sequentially arranged on the sensing electrode layer;

[0013] When a driving voltage is applied between the lower driving electrode layer and the upper driving electrode layer, the piezoelectric material layer causes the comb-tooth structure at the free ends of one group of sensing electrodes to vibrate up and down relative to the comb-tooth structure at the free ends of another group of sensing electrodes, thereby generating a current signal corresponding to the electric field strength to be measured, and outputting the current signal.

[0014] Furthermore, the thickness of the sensing electrode layer is between 1 nanometer and 5 millimeters, and the material of the sensing electrode layer is conductive silicon.

[0015] Furthermore, the invention further comprises a first insulating layer arranged on the upper driving electrode layer, a second insulating layer arranged between the sensing electrode layer and the lower driving electrode layer, and a third insulating layer arranged between the substrate and the sensing electrode layer.

[0016] Further, it also includes an upper driving electrode pad hole and a lower driving electrode pad hole;

[0017] The upper driving electrode pad hole is formed by etching downwards from the first insulating layer, and its depth passes through the first insulating layer and ends at the upper driving electrode layer. An upper driving electrode pad for applying a driving voltage to the upper driving electrode layer is arranged in the upper driving electrode pad hole;

[0018] The lower driving electrode pad hole is formed by etching downward from the first insulating layer, and its depth passes through the first insulating layer, the upper driving electrode layer and the piezoelectric material layer, and terminates at the lower driving electrode layer. A lower driving electrode pad for applying a driving voltage to the lower driving electrode layer is provided in the lower driving electrode pad hole.

[0019] Further, it also includes a sensing electrode pad hole;

[0020] The sensing electrode pad hole is formed by etching downward from the first insulating layer, and its depth passes through the first insulating layer, the upper driving electrode layer, the piezoelectric material layer, the lower driving electrode layer and the second insulating layer, and ends at the sensing electrode. The sensing electrode pad hole is provided with a sensing electrode pad for outputting the current corresponding to the electric field to be measured.

[0021] Furthermore, the thickness of the piezoelectric material layer is between 10 nanometers and 5 centimeters, and the material is a combination of one or more of the following materials: lead zirconate titanate, modified lead titanate, lead lanthanum titanate, lead lanthanum zirconate titanate, zinc oxide aluminum nitride or relaxor ferroelectric single crystal.

[0022] Furthermore, the thickness of the lower driving electrode layer and the upper driving electrode layer is between 1 nanometer and 5 millimeters, and the material thereof is selected from one of the following materials: Ir, Pt, Al, Cu and Au.

[0023] Furthermore, the thickness of the first insulating layer, the second insulating layer and the third insulating layer are respectively between 1 nanometer and 1 centimeter, and the first insulating layer, the second insulating layer and the third insulating layer are composed of a silicon dioxide layer and a silicon nitride layer or a composite insulating layer composed of silicon dioxide and silicon nitride.

[0024] Furthermore, the distance from the lower surface of the cantilever beam structure to the bottom surface of the substrate is 1 micron to 10 centimeters; the length of the cantilever beam structure is 1 micron to 10 centimeters, the width is 1 micron to 10 centimeters, and the thickness is 1 micron to 10 centimeters; the distance between the two groups of comb tooth structures along the width direction of the cantilever beam structure is 1 micron to 5 millimeters, and the gap between the two groups of comb tooth structures along the length direction of the cantilever beam structure is 1 micron to 5 centimeters.

[0025] Compared with the prior art, the piezoelectrically driven micro electric field sensor disclosed in the utility model has the following beneficial effects: since a comb tooth structure is prepared at the free end of the piezoelectric driving beam, the sensitive structure of the sensor is simplified and the complexity of the process for preparing the sensor is reduced, thereby improving the yield rate; further, since the comb tooth upper surface and side surface of the free end of the sensing electrode layer can alternately play the role of charge sensing and shielding the electric field during the operation of the sensor, the induced charge amount of the sensing electrode layer is increased, thereby improving the sensitivity of the piezoelectrically driven micro electric field sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a three-dimensional structural diagram of the piezoelectric driven micro electric field sensor disclosed in the present invention;

[0027] Figure 2a yes Figure 1 The cross-sectional working principle diagram of the piezoelectric driven micro electric field sensor along the AA′ direction is shown, in which the comb teeth of the first sensing electrode are tilted upward to sense the charge;

[0028] Figure 2b yes Figure 1 The cross-sectional working principle diagram of the piezoelectric driven micro electric field sensor along the AA′ direction is shown, in which the comb teeth of the second sensing electrode are tilted upward to sense the charge;

[0029] Figure 3 Shows Figure 1 Schematic diagram of the structural hierarchy of the piezoelectrically driven micro electric field sensor shown;

[0030] Figure 4a yes Figure 1 A cross-sectional view of the piezoelectric driven micro electric field sensor along the BB′ direction;

[0031] Figure 4b yes Figure 1 A cross-sectional view of the piezoelectric driven micro electric field sensor along the CC direction;

[0032] Figure 4c yes Figure 1 A cross-sectional view of the piezoelectrically driven micro electric field sensor along direction DD′ is shown.

[0033] In the figure: 1, first upper driving electrode pad; 2, first sensing electrode pad; 3, first lower driving electrode pad; 4, cantilever beam; 5, second upper driving electrode pad; 6, second sensing electrode pad; 7, second lower driving electrode pad; 8, substrate; 9, first insulating layer; 10, sensing electrode layer; 11, second insulating layer; 12, upper driving electrode layer; 13, piezoelectric material layer; 14, lower driving electrode layer; 15, third insulating layer; 16, sensing electrode pad hole; 17, upper driving electrode pad hole; 18, lower driving electrode pad hole; 19, first sensing electrode comb teeth; 20, second sensing electrode comb teeth; 21, sensing electrode. DETAILED DESCRIPTION

[0034] like Figure 1 The figure shows a piezoelectric driven micro electric field sensor disclosed in the utility model, comprising two groups of substrates 8 arranged opposite to each other, a sensing electrode layer 10 arranged on the substrate 8, and a driving structure for driving the sensing electrode layer 10 to vibrate;

[0035] One end of the sensing electrode layer 10 is disposed on the substrate 8, and the other end is suspended in the air to form a cantilever beam structure. A comb tooth structure 21 is disposed at the free end of the sensing electrode layer 10. The comb tooth structures of the two groups of sensing electrode layers 10 are arranged opposite to each other and interlaced to form a sensor sensitive structure.

[0036] The driving structure includes a lower driving electrode layer 14, a piezoelectric material layer 13 and an upper driving electrode layer 12 which are sequentially arranged on the sensing electrode layer 10;

[0037] When a driving voltage is applied between the lower driving electrode layer 14 and the upper driving electrode layer 12, the piezoelectric material layer 13 causes the comb-tooth structure at the free end of one group of sensing electrode layers 10 to vibrate up and down relative to the comb-tooth structure at the free end of another group of sensing electrode layers 10, thereby generating a current signal corresponding to the electric field strength to be measured, and outputting the current signal.

[0038] Specifically, Figure 1 and Figure 3As shown, two groups of substrates 8 are arranged opposite to each other. Preferably, the substrate 8 is an SOI (silicon substrate). A sensing electrode layer 10 is arranged on the substrate 8. One end of the sensing electrode layer 10 is fixed on the substrate 8, and the other end is suspended to form a cantilever beam structure. The free end of the sensing electrode layer 10 forms a comb tooth structure, that is, the comb tooth structure of one group of sensing electrodes forms a first sensing electrode comb tooth 19, and the comb tooth structure of the other group of sensing electrodes forms a second sensing electrode comb tooth 20. The two groups of sensing electrode comb teeth are arranged to intersperse with each other to form a sensor sensitive structure. A driving structure for driving the comb tooth structure of the free section of the sensing electrode layer 10 to vibrate is provided on the sensing electrode layer 10. The driving structure includes a lower driving electrode layer 14, which are sequentially arranged on the sensing electrode layer 10 and form a cantilever beam structure, The piezoelectric material layer 13 and the upper driving electrode layer 12, when a driving voltage is applied between the lower driving electrode layer 14 and the upper driving electrode layer 12, the free end of the cantilever beam structure 4 can vibrate up and down under the driving of the piezoelectric material layer so that the sensing electrode layer induces charges in the electric field to be measured, thereby forming a current, that is, the piezoelectric material layer 13 causes the comb-tooth structure of the free end of one group of sensing electrode layers 10 to vibrate up and down relative to the comb-tooth structure of the free end of another group of sensing electrode layers 10 to generate a current intensity proportional to the intensity of the electric field to be measured, and the sensing electrode layer 10 outputs the current signal (that is, when measuring the electric field to be measured, the comb-tooth structure of the sensing electrode layer becomes a sensing electrode, and the mutual movement of the sensing electrodes generates a corresponding induced current).

[0039] In this embodiment, if Figure 1 , Figure 3 , Figure 4a , Figure 4b as well as Figure 4c As shown, a piezoelectric driven micro electric field sensor disclosed in the utility model further includes an upper driving electrode pad hole 17 and a lower driving electrode pad hole 18;

[0040] The upper driving electrode pad hole 17 is formed by etching downwards from the first insulating layer 9, and its depth passes through the first insulating layer 9 and ends at the upper driving electrode layer 12. The upper driving electrode pad hole 17 is provided with an upper driving electrode pad for applying a driving voltage to the upper driving electrode layer 12. The two groups of upper driving electrode layers are respectively provided with a first upper driving electrode pad 1 and a second upper driving electrode pad 5, so that the upper driving electrode layers are respectively connected to the first end of the driving circuit through a wire;

[0041] The lower driving electrode pad hole 18 is formed by etching downwards from the first insulating layer 9, and its depth passes through the first insulating layer 9, the upper driving electrode layer 12 and the piezoelectric material layer 13, and terminates at the lower driving electrode layer 14. A lower driving electrode pad for applying a driving voltage to the lower driving electrode layer 14 is provided in the lower driving electrode pad hole 18. The two groups of lower driving electrode layers 14 are respectively provided with a first lower driving electrode pad 3 and a second lower driving electrode pad 7, so that the lower driving electrode layer can be connected to the other end of the driving circuit through wires.

[0042] The piezoelectric driven micro electric field sensor disclosed in the utility model further includes a sensing electrode pad hole 16;

[0043] The sensing electrode pad hole 16 is formed by etching downwards from the first insulating layer 9, and its depth passes through the first insulating layer 9, the upper driving electrode layer 12, the piezoelectric material layer 13, the lower driving electrode layer 14 and the second insulating layer 11, and terminates at the sensing electrode layer 10. The sensing electrode pad hole 16 is provided with a sensing electrode pad for outputting the current corresponding to the electric field to be measured. The two groups of sensing electrode layers are provided with a first sensing electrode pad 2 and a second sensing electrode pad 6, respectively, so as to connect the sensing electrode layer 10 with two ends of the measuring circuit through a wire.

[0044] The piezoelectric driven micro electric field sensor disclosed in the utility model further includes a first insulating layer 9 arranged on the upper driving electrode layer 12, a second insulating layer 11 arranged between the sensing electrode layer 10 and the lower driving electrode layer 14, and a third insulating layer 15 arranged between the substrate 8 and the sensing electrode layer 10. The first, second and third insulating layers are used for insulation between the upper driving electrode layer, the lower driving electrode layer and the sensing electrode layer, and between the sensing electrode layer and the substrate, respectively, to ensure that there is no short circuit between the parts. Specifically, refer to Figure 4a , Figure 4b and Figure 4c The area of ​​the insulating layer of the piezoelectric driven micro electric field sensor of the embodiment of the present invention is larger than the upper and lower adjacent electrode layers to ensure that the upper and lower electrodes will not short-circuit when the electrode layers are manufactured. For example, the area of ​​the first insulating layer 9 is larger than the underlying upper driving electrode layer 12; the area of ​​the second insulating layer 11 is larger than the underlying lower driving electrode layer 14. Piezoelectric material is an excellent insulating material, so the piezoelectric material layer can also be used as an insulating material layer, and the area of ​​the piezoelectric material layer 13 is larger than the underlying upper driving electrode layer 12 and the underlying lower driving electrode layer 14.

[0045] refer to Figure 1 , Figure 2a and Figure 2bThe working principle of the piezoelectric driven micro electric field sensor of the embodiment of the present invention is explained below: when in working state, the piezoelectric driven micro electric field sensor of the embodiment of the present invention is placed in the electric field to be measured, and the driving circuit (not shown) applies two sets of voltages with a certain frequency and periodic amplitude changes to the first upper driving electrode layer and the first lower driving electrode layer and the second upper driving electrode layer and the second lower driving electrode layer respectively through the first upper driving electrode pad and the first lower driving electrode pad and the second upper driving electrode pad and the second lower driving electrode pad, and the phase difference between the two sets of voltages is 180 degrees. Driven by the driving voltage, the piezoelectric material layer drives the free end of the cantilever beam structure at the position to vibrate up and down in the vertical direction, and the comb tooth structure of the free end of the sensing electrode layer also vibrates up and down at the same time. The vibration can be a resonant vibration or a forced vibration.

[0046] The cantilever beam structure can be divided into two parts that vibrate vertically (e.g. Figure 1 The upper part and Figure 1 The upper and lower cantilever beams vibrate in opposite directions, that is, when the upper cantilever beam moves upward, the lower cantilever beam moves downward. The initial state without driving voltage is that all cantilever beams are on the same horizontal plane. When driving voltage is applied, the free end of one cantilever beam rises upward, and the free end of the other cantilever beam bends downward. The working state of the comb electrode is as follows: Figure 2a As shown. That is to say, when the upper part of the cantilever beam moves upward, the lower part of the cantilever beam moves downward, and the comb teeth of the free end of the cantilever beam structure that are tilted and higher than the initial horizontal plane (the comb teeth structure of the free end of the sensing electrode layer) are exposed to the electric field to be measured, and the induced charge on the surface of the sensing electrode increases. At this time, the comb teeth of the free end of the cantilever beam that are tilted upward serve as the sensing electrode and also play a role in shielding the electric field. The comb teeth of the free end of the cantilever beam that are bent downward and lower than the initial horizontal plane are shielded by the comb teeth of the free end of the cantilever beam that are tilted upward, which plays a shielding role, so that the induced charge on the surface of the electrode is reduced. Due to the periodic change in the amplitude of the driving voltage, the above-mentioned tilting and bending states of the cantilever beam appear alternately, and the amount of induced charge on the surface of the sensing electrode changes periodically, thereby forming an alternating current, which is output by the first sensing electrode pad 2 and the second sensing electrode pad 6 in a differential form. Therefore, the amplitude of its output current is proportional to the magnitude of the electric field strength to be measured.

[0047] The piezoelectric driven micro electric field sensor disclosed in the utility model has a comb structure 21 made at the free end of the cantilever beam 4, a lower driving electrode layer 14, a piezoelectric material layer 13 and an upper driving electrode layer 12 are sequentially arranged on the cantilever beam 4, and there is no material layer on the first sensing electrode comb 19 and the second sensing electrode comb 20, which simplifies the sensor structure and reduces the complexity of the process for preparing the sensor sensitivity, thereby improving the yield rate. Further, as Figure 2bAs shown, since the upper surface and side surface of the comb teeth at the free end of the cantilever beam 4 can be used for charge induction, the induced charge of the sensing electrode layer is increased, thereby improving the sensitivity of the piezoelectric driven micro electric field sensor. Since the piezoelectric driving layer of the sensor is connected to other structural layers using MEMS technology, the sensor has a simple structure, small size, low power consumption, and is easy to mass produce.

[0048] Furthermore, the thickness of the sensing electrode layer 10 is between 1 nanometer and 5 millimeters, and the material of the sensing electrode layer 10 is silicon, which can further increase the induced charge of the sensing electrode layer, increase the induced current, and improve the sensitivity of the piezoelectrically driven SOI micro electric field sensor.

[0049] Furthermore, the thickness of the piezoelectric material layer 13 is between 10 nanometers and 5 centimeters, and its material is a combination of one or more of the following materials: lead zirconate titanate, modified lead titanate, lead lanthanum titanate, lead lanthanum zirconate titanate, PVDF, zinc oxide, aluminum nitride or relaxor ferroelectric single crystal.

[0050] Furthermore, the thickness of the lower driving electrode layer 14 and the upper driving electrode layer 12 is between 1 nanometer and 5 millimeters, and the material thereof is selected from one of the following materials: metals such as Ir, Pt, Al, Cu and Au, and may also be made of other metal materials.

[0051] Furthermore, the thickness of the first insulating layer 9, the second insulating layer 11 and the third insulating layer 15 are respectively between 1 nanometer and 1 centimeter, and the first insulating layer 9, the second insulating layer 11 and the third insulating layer 15 are made of a silicon dioxide layer and a silicon nitride layer or a composite insulating layer composed of silicon dioxide and silicon nitride or other insulating materials.

[0052] Furthermore, if Figure 1 As shown, the distance L1 from the lower surface of the cantilever beam structure 21 to the bottom surface of the substrate 8 is 1 micron to 10 centimeters; the length L2 of the cantilever beam structure 21 is 1 micron to 10 centimeters, the width L3 is 1 micron to 10 centimeters, and the thickness L4 is 1 micron to 10 centimeters; the distance L5 between the two groups of comb tooth structures along the width direction of the cantilever beam structure 21 is 1 micron to 5 millimeters, and the gap L6 between the two groups of comb tooth structures along the length direction of the cantilever beam structure 21 is 1 micron to 5 centimeters.

[0053] The piezoelectric driven micro electric field sensor of the embodiment of the present invention can be prepared by MEMS process. The preparation process and method may include: preparing the first insulating layer 9 and the second insulating layer 11 by sputtering, PLVCD, PEVCD or oxidation; preparing the upper driving electrode layer and the lower driving electrode layer by sputtering or evaporation; preparing the piezoelectric material layer by sol-gel, evaporation, bonding or sputtering process; and releasing the comb structure at the free end of the sensor cantilever beam and the suspension below the cantilever beam by deep etching dry method.

[0054] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A piezoelectric driven micro electric field sensor, characterized in that: The invention comprises two groups of substrates arranged opposite to each other, a sensing electrode layer arranged on the substrate, and a driving structure for driving the sensing electrode layer to vibrate; One end of the sensing electrode layer is arranged on the substrate, and the other end is suspended in the air to form a cantilever beam structure. The free end of the sensing electrode layer is provided with a comb tooth structure. The comb tooth structures of two groups of sensing electrode layers are arranged opposite to each other and interlaced with each other to form a sensor sensitive structure. The driving structure comprises a lower driving electrode layer, a piezoelectric material layer and an upper driving electrode layer which are sequentially arranged on the sensing electrode layer; When a driving voltage is applied between the lower driving electrode layer and the upper driving electrode layer, the piezoelectric material layer causes the comb-tooth structures at the free ends of one group of sensing electrode layers to vibrate up and down relative to the comb-tooth structures at the free ends of the other group of sensing electrode layers, thereby generating a current signal proportional to the electric field strength to be measured, and outputting the current signal.

2. The piezoelectric driven micro electric field sensor according to claim 1, characterized in that: The thickness of the sensing electrode layer is between 1 nanometer and 5 millimeters, and the material of the sensing electrode layer is conductive silicon.

3. The piezoelectric driven micro electric field sensor according to claim 1 or 2, characterized in that: The invention also includes a first insulating layer arranged on the upper driving electrode layer, a second insulating layer arranged between the sensing electrode layer and the lower driving electrode layer, and a third insulating layer arranged between the substrate and the sensing electrode layer.

4. The piezoelectric driven micro electric field sensor according to claim 3, characterized in that: Also includes an upper drive electrode pad hole and a lower drive electrode pad hole; The upper driving electrode pad hole is formed by etching downwards from the first insulating layer, and its depth passes through the first insulating layer and ends at the upper driving electrode layer. An upper driving electrode pad for applying a driving voltage to the upper driving electrode layer is arranged in the upper driving electrode pad hole; The lower driving electrode pad hole is formed by etching downward from the first insulating layer, and its depth passes through the first insulating layer, the upper driving electrode layer and the piezoelectric material layer, and terminates at the lower driving electrode layer. A lower driving electrode pad for applying a driving voltage to the lower driving electrode layer is provided in the lower driving electrode pad hole.

5. The piezoelectric driven micro electric field sensor according to claim 4, characterized in that: Also included are sensing electrode pad holes; The sensing electrode pad hole is formed by etching downward from the first insulating layer, and its depth passes through the first insulating layer, the upper driving electrode layer, the piezoelectric material layer, the lower driving electrode layer and the second insulating layer, and ends at the sensing electrode layer. The sensing electrode pad hole is provided with a sensing electrode pad for outputting the current corresponding to the electric field to be measured.

6. The piezoelectric driven micro electric field sensor according to claim 1, characterized in that: The thickness of the piezoelectric material layer is between 10 nanometers and 5 centimeters, and the material is a combination of one or more of the following materials: lead zirconate titanate, modified lead titanate, lead lanthanum titanate, lead lanthanum zirconate titanate, zinc oxide aluminum nitride or relaxor ferroelectric single crystal.

7. The piezoelectric driven micro electric field sensor according to claim 1, characterized in that: The thickness of the lower driving electrode layer and the upper driving electrode layer is between 1 nanometer and 5 millimeters, and the material thereof is selected from one of the following materials: Ir, Pt, Al, Cu and Au.

8. The piezoelectric driven micro electric field sensor according to claim 3, characterized in that: The thickness of the first insulating layer, the second insulating layer and the third insulating layer are respectively between 1 nanometer and 1 centimeter. The first insulating layer, the second insulating layer and the third insulating layer are composed of a silicon dioxide layer and a silicon nitride layer or a composite insulating layer composed of silicon dioxide and silicon nitride.

9. The piezoelectric driven micro electric field sensor according to claim 3, characterized in that: The distance from the lower surface of the cantilever beam structure to the bottom surface of the substrate is 1 micron to 10 centimeters; the length of the cantilever beam structure is 1 micron to 10 centimeters, the width is 1 micron to 10 centimeters, and the thickness is 1 micron to 10 centimeters; the distance between the two groups of comb tooth structures along the width direction of the cantilever beam structure is 1 micron to 5 millimeters, and the gap between the two groups of comb tooth structures along the length direction of the cantilever beam structure is 1 micron to 5 centimeters.

Images