Electric field sensor, preparation method and application

Abstract

The electric field sensor comprises a piezoelectric material layer, a resistive material layer and an electrode, the resistive material layer is arranged on the surface of the piezoelectric material layer, and the electrode is arranged on the surface of the resistive material layer; when an external electric field is applied, the piezoelectric material layer drives the resistive material layer to deform, and the surface resistance of the resistive material layer is changed. According to the invention, the limitation of a traditional sensing technology is broken through by fusing a piezoelectric-resistive dual-mode sensing mechanism. According to the heterostructure device constructed based on the micro-nano manufacturing process, a strain-charge collaborative coupling electric field response model is realized, and the technical defects of a traditional device in the aspects of high precision and high sensitivity are effectively overcome. Different from a conventional mechanical coupling type sensor, a nickel-based oxide functional layer is heteroepitaxially formed on the surface of a piezoelectric substrate by adopting a pulse laser deposition process, a micro-structure sensor with a wide dynamic response range and strong field detection capability is constructed, and a full-time-domain voltage state sensing solution is provided for a high-voltage power transmission and transformation system.

Description

Technical Field

[0001] The present invention belongs to the technical field of sensors, and in particular relates to an electric field sensor, a preparation method and an application thereof. Background Art

[0002] Under the current development environment, the construction of new power systems is facing the technical bottleneck of weak perception capabilities. Due to the limitations of information collection, traditional perception technologies are difficult to achieve full-link visual monitoring and precise quantitative analysis, which in turn threatens the reliability and stability of power grid operation. To this end, promoting the development and application of intelligent sensing devices and improving the global perception system of energy and power systems have become the key support for promoting the deep integration of digital technology and power infrastructure. The current mainstream non-contact measurement methods of electric fields mainly include D-dot electric field sensing technology and sensor devices designed based on principles such as electro-optical effect, piezoelectric effect and electrostatic force effect. However, the placement of D-dot electric field sensors may cause electric field distribution distortion, which not only affects the stability of system operation, but also makes the potential of the measured area susceptible to environmental factors. There are technical bottlenecks in the implementation of high-frequency electric field detection using the electro-optical principle and the electrostatic force principle, which are mainly manifested in limited effective bandwidth and insufficient range coverage. In contrast, piezoelectric sensors exhibit wide-band response characteristics from DC to several kilohertz, and their excellent signal-to-noise ratio and resolution indicators ensure the accurate capture of electric field signals in strong electromagnetic environments. It should be pointed out that although the sensing system based on the piezoelectric-optical detection principle has high sensitivity, its structural complexity and manufacturing cost limit its practical application. Sensors using piezoelectric-capacitive coupling need to accurately detect the microscopic displacement of the inverse piezoelectric material, which faces the dual challenges of high technical implementation difficulty and high measurement error in actual operation. Summary of the invention

[0003] The object of the present invention is to provide an electric field sensor, a preparation method and an application thereof, so as to solve the above-mentioned problems.

[0004] To achieve the above object, the present invention adopts the following technical solutions: An electric field sensor comprises a piezoelectric material layer, a resistive material layer and an electrode, wherein the resistive material layer is arranged on the surface of the piezoelectric material layer, and the electrode is arranged on the surface of the resistive material layer; when an external electric field is applied, the piezoelectric material layer drives the resistive material layer to deform, thereby changing the surface resistance of the resistive material layer itself.

[0005] Furthermore, the piezoelectric material layer is piezoelectric ceramic PZT, relaxor ferroelectric single crystal PMN-PT or PZN-PT.

[0006] Furthermore, the resistive material layer is vanadium dioxide VO2, zinc oxide ZnO, nickel oxide NiO, NdNiO3, SmNiO3, tin oxide SnO2, indium tin oxide ITO, LSMO or LBMO.

[0007] Furthermore, the electrode is a Pt electrode; the electrode is externally connected to a test PCB board.

[0008] A method for preparing an electric field sensor comprises the following steps: preparing a single crystal substrate; Growing and preparing a resistive material layer on a single crystal substrate; Micro-nano processing surface electrodes on the resistive material layer and connecting them to the test PCB board; An external electric field is applied to adjust the resistance of the resistive material layer to realize a high-sensitivity electric field sensor.

[0009] Further, the preparing of the single crystal substrate comprises: The single crystal substrate is single-sided polished with a surface roughness requirement of less than 10 nm, and annealed at 570 K to remove surface stress.

[0010] Furthermore, the step of growing and preparing a resistive material layer on a single crystal substrate comprises: The resistive material layer is deposited on a single-side polished single crystal substrate using KrF excimer laser pulse laser deposition.

[0011] Furthermore, the micro-nano processing of the surface electrode on the resistive material layer and connecting it to the test PCB board includes: A layer of Pt electrode is sputtered on the surface of the resistive material layer using magnetron sputtering technology, and then the electrode is patterned using micro-nano processing technology. In this process, a double-sided alignment exposure machine is used, and a micro-nano processing process of spin coating photoresist, drying, exposure, development, and etching is adopted. The micro-nano processing technology based on lithography and etching is used to realize the patterning of the device surface electrode, and finally a thermosonic welder is used to interconnect the device with the test PCB board.

[0012] Furthermore, by applying an external electric field, the single crystal substrate will be strained by the electric field, causing the upper resistive material layer to deform, and utilizing the interface charge effect to induce the distortion of the resistive material lattice structure, thereby changing the surface resistance of the film itself.

[0013] An application of an electric field sensor is used to provide full-time domain voltage state perception for a high-voltage power transmission and transformation system.

[0014] Compared with the prior art, the present invention has the following technical effects: The present invention breaks through the limitations of traditional sensing technology by integrating the piezoelectric-resistive dual-mode sensing mechanism. The heterostructure device constructed based on the micro-nano manufacturing process realizes the electric field response model of strain-charge cooperative coupling, effectively overcoming the technical shortcomings of traditional devices in high precision and high sensitivity. The field-induced strain coupling coefficient can reach up to 68 ppm (kv / m). Different from conventional mechanical coupling sensors, a pulsed laser deposition process is used to heteroepitaxially grow a nickel-based oxide functional layer on the surface of the piezoelectric substrate to construct a microstructure sensor with a wide dynamic response range and strong field detection capability, providing a full-time domain voltage state perception solution for high-voltage transmission and transformation systems.

[0015] The present invention constructs a sensitive resistive variable film and a piezoelectric heterostructure, utilizes field-induced strain, ferroelectric domain polarization, and interface charge effect, regulates the lattice structure of the resistive variable material, and changes in carrier concentration, thereby achieving a large change in resistance, and the field-induced strain coupling coefficient can reach a maximum of 68ppm (kv / m). Therefore, a weak signal change in the external electric field can achieve a large change in resistance, and a highly sensitive electric field sensor can be prepared for non-invasive electric field measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a polarization-electric field hysteresis loop and a butterfly-shaped strain-electric field loop; Figure 2 is the XRD diffraction curve of NdNiO3 single crystal thin film; Figure 3 It is a technology roadmap for micro-nano processing; Figure 4 Figure 1 is a diagram of the sensor device to be tested; Figure 5 Performance test diagram of electric field sensor.

[0017] Figure 6 The characteristic that the surface resistance of the film changes linearly under different electric fields. DETAILED DESCRIPTION

[0018] The present invention is further described below in conjunction with the accompanying drawings: Embodiment 1, an electric field sensor, comprises a piezoelectric material layer, a resistive material layer and an electrode, wherein the resistive material layer is arranged on the surface of the piezoelectric material layer, and the electrode is arranged on the surface of the resistive material layer; when an external electric field is applied, the piezoelectric material layer drives the resistive material layer to deform, thereby changing the surface resistance of the resistive material layer itself.

[0019] The piezoelectric material layer is piezoelectric ceramic PZT, relaxor ferroelectric single crystal PMN-PT or PZN-PT.

[0020] The resistive material layer is vanadium dioxide, rare earth nickelate, perovskite manganese oxide, lithium cobaltate or transition metal oxide.

[0021] The electrode is a Pt electrode; the electrode is externally connected to a test PCB board.

[0022] Embodiment 2, the present invention aims to provide a method for preparing an electric field sensor, which adjusts the lattice structure of the resistive material and the change of carrier concentration through field-induced strain and interface charge effect to achieve a large change in resistance. Piezoelectric materials can be selected from piezoelectric ceramics PZT, relaxor ferroelectric single crystals PMN-PT, PZN-PT, etc. Resistive materials can be selected from resistive oxides in strong-relationship electronic systems, such as vanadium dioxide, rare earth nickelates, perovskite manganese oxides, lithium cobalt oxides, and other transition metal oxides. Taking the piezoelectric material PMN-PT single crystal and the resistive material NdNiO3 as an example, the specific implementation is as follows: 1. Single crystal substrate preparation: PMN-PT (001) single crystal substrate should have good FE and piezoelectric properties, such as Figure 1 The typical polarization-electric field hysteresis loop and butterfly-shaped strain-electric field loop of PMN-PT (001) substrate are shown in Figure 1. The surface roughness is required to be within 10nm, and annealing at 570K for 10h is required to remove surface stress.

[0023] 2. Preparation of NdNiO3 thin film on substrate: Using KrF excimer laser (λ=248nm) pulsed laser deposition (PLD), NNO thin film was deposited on a single-side polished (001) oriented PMN-PT single crystal substrate. Growth temperature 700℃, growth oxygen pressure 20Pa, target substrate distance 4.5cm, laser energy 1.96W, laser frequency 5Hz, after 10min of growth, cooled to room temperature at a rate of 5℃ / min. The grown NdNiO3 single crystal film should have Figure 2 The XRD diffraction curve is shown.

[0024] 3. Micro-nano manufacturing to construct surface electrodes: First, a 20nm Pt electrode is sputtered on the surface of the film using magnetron sputtering technology, and then the electrode is patterned using Wiener processing. The process uses a URE-2000S / 25 double-sided alignment exposure machine. The micro-nano processing technology route is as follows Figure 3 As shown. For a 2-micron thick positive photoresist, the resolution is 1.5 microns, which is easy to overlay and easy to operate. We use the micro-nano processing process of spin coating photoresist, drying, exposure, development, and etching. The micro-nano processing technology based on photolithography and etching realizes the patterning of the device surface electrode. Finally, a thermosonic welder is used to interconnect the device with the test PCB board, as shown in the figure. Figure 4 shown.

[0025] 4. Place the sensor in a parallel capacitor plate test setup, such as Figure 5As shown. By applying an external electric field, the PMN-PT piezoelectric single crystal will be strained by the electric field, driving the upper NdNiO3 epitaxial film to deform, and using the interface charge effect to induce the lattice structure of the resistive material to distort, thereby changing the surface resistance of the film itself. According to the linear change of the film surface resistance under different electric fields, the electric field strength in the current environment can be obtained by using the resistance value, as shown in Figure 6 shown.

[0026] The present invention adopts nickelate film as a resistive material, and the lattice structure of the nickelate film will be distorted under micro-deformation, thereby changing the surface resistance of the film itself. The nickelate film can solve the nonlinear problem of piezoresistive sensors to a large extent, and can still maintain good resistive performance under high temperature and harsh environment. Since nickelate has the mutual coupling characteristics between charge, spin, lattice and orbit, stress has a great influence on the occupancy of nickelate electron orbits and lattice distortion, resulting in a huge change in its own resistance, so that the piezoelectric-resistive electric field sensor prepared by it has a large range and a wide frequency response range. Compared with the existing electric field sensors, the electric field sensor of the present invention has broad development prospects under the application requirements of large range, wide frequency response range, etc.

[0027] Interfacial charge effect: refers to the phenomenon of abnormal charge distribution or charge accumulation at the contact interface of two different materials due to physical or chemical interactions between the materials. This effect is widely present in semiconductor devices, electronic components, energy devices (such as batteries and solar cells), and biomaterials, and may significantly affect the performance and stability of the device.

[0028] Single-sided polishing to a surface roughness of less than 10 nm significantly reduces surface defects, improves the crystallization quality and mechanical properties of the single crystal substrate, and provides a uniform and dense growth substrate for the resistive material layer, thereby improving the sensitivity and stability of the sensor.

[0029] The 570K annealing treatment effectively eliminates surface stress, enhances the mechanical stability and durability of the single crystal substrate, and ensures that the sensor maintains stable performance during long-term use.

[0030] KrF excimer laser pulsed laser deposition (PLD) technology is used to prepare a resistive material layer with precise chemical measurement and uniform and dense microstructure through the interaction between high-energy laser pulses and target materials. PLD technology can accurately control the chemical composition and microstructure of the film, improve the performance of the resistive material and the sensitivity of the sensor, enabling it to detect weak electric field changes.

[0031] The Pt electrode prepared by magnetron sputtering technology has high conductivity and stability, ensuring efficient signal transmission and long-term stability of the sensor. Magnetron sputtering technology bombards the target material with a high-energy ion beam, sputtering it onto the surface of the resistive material layer to form a uniform and dense thin film coating, which optimizes the contact interface between the electrode and the resistive material layer.

[0032] The micro-nano processing technology realizes the patterning of electrodes, optimizes the electrode structure, and further improves the sensitivity and frequency response of the sensor. Through the steps of spin coating photoresist, drying, exposure, development, etching, etc., the fine processing and patterning of electrodes are realized.

[0033] Thermoacoustic welding machine realizes reliable interconnection between the device and the test PCB board, ensuring the electrical connection stability of the sensor and the accuracy of the test results. Thermoacoustic welding technology realizes fast and efficient welding between the device and the PCB board through the combination of heat energy and ultrasonic waves, avoiding the contact resistance and mechanical stress that may be introduced by traditional welding methods.

[0034] By applying an external electric field, the single crystal substrate is strained, driving the deformation of the resistive material layer, and using the interface charge effect to induce the distortion of the resistive material lattice structure, thereby changing the surface resistance of the film. This mechanism enhances the sensitivity of the sensor, enabling it to detect weak electric field signals, and is suitable for high-precision measurement scenarios.

[0035] High sensitivity: Thanks to the high-quality resistive material layer, optimized electrode structure and interface charge effect, the sensor can detect weak electric field signals with significantly improved sensitivity.

[0036] Wide frequency response: Micro-nano processing technology optimizes the frequency response characteristics of the sensor, enabling it to work stably within a wide frequency range and meet the needs of a variety of applications.

[0037] High stability: The annealing treatment of the single crystal substrate, the high-quality resistive material layer and the stable electrode connection jointly improve the long-term stability and reliability of the sensor, enabling it to maintain stable performance in complex environments.

[0038] Environmental adaptability: Optimized material selection and preparation process enable the sensor to maintain stable performance under different environmental conditions, broaden the scope of application, and be suitable for a variety of electric field measurement scenarios.

[0039] Finally, it should be noted that 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 above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. An electric field sensor, characterized in that: It includes a piezoelectric material layer, a resistive material layer and an electrode. The resistive material layer is arranged on the surface of the piezoelectric material layer, and the electrode is arranged on the surface of the resistive material layer. When an external electric field is applied, the piezoelectric material layer drives the resistive material layer to deform, thereby changing the surface resistance of the resistive material layer itself.

2. An electric field sensor according to claim 1, characterized in that: The piezoelectric material layer is piezoelectric ceramic PZT, relaxor ferroelectric single crystal PMN-PT or PZN-PT.

3. An electric field sensor according to claim 1, characterized in that: The resistive material layer is vanadium dioxide VO2, zinc oxide ZnO, nickel oxide NiO, NdNiO3, SmNiO3, tin oxide SnO2, indium tin oxide ITO, LSMO or LBMO.

4. The electric field sensor according to claim 1, characterized in that: The electrode is a Pt electrode; the electrode is externally connected to a test PCB board.

5. A method for preparing an electric field sensor, characterized in that: The electric field sensor according to any one of claims 1 to 4 comprises the following steps: preparing a single crystal substrate; Growing and preparing a resistive material layer on a single crystal substrate; Micro-nano processing surface electrodes on the resistive material layer and connecting them to the test PCB board; An external electric field is applied to adjust the resistance of the resistive material layer to realize a high-sensitivity electric field sensor.

6. The method for preparing an electric field sensor according to claim 5, characterized in that: The step of preparing a single crystal substrate comprises: The single crystal substrate is single-sided polished with a surface roughness requirement of less than 10 nm, and annealed at 570 K to remove surface stress.

7. The method for preparing an electric field sensor according to claim 5, characterized in that: The method of growing and preparing a resistive material layer on a single crystal substrate comprises: The resistive material layer is deposited on a single-side polished single crystal substrate using KrF excimer laser pulse laser deposition.

8. The method for preparing an electric field sensor according to claim 5, characterized in that: The micro-nano processing of the surface electrode on the resistive material layer and connecting it to the test PCB board includes: A layer of Pt electrode is sputtered on the surface of the resistive material layer using magnetron sputtering technology, and then the electrode is patterned using micro-nano processing technology. In this process, a double-sided alignment exposure machine is used, and a micro-nano processing process of spin coating photoresist, drying, exposure, development, and etching is adopted. The micro-nano processing technology based on lithography and etching is used to realize the patterning of the device surface electrode, and finally a thermosonic welder is used to interconnect the device with the test PCB board.

9. The method for preparing an electric field sensor according to claim 5, characterized in that: By applying an external electric field, the single crystal substrate will be strained due to the electric field, causing the upper resistive material layer to deform, and utilizing the interface charge effect to induce the distortion of the resistive material lattice structure, thereby changing the surface resistance of the film itself.

10. An application of an electric field sensor, characterized in that: An electric field sensor according to any one of claims 1 to 4 is used to provide full-time domain voltage state perception for a high-voltage power transmission and transformation system.

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