Preparation method of ultrasonic water immersion probe and ultrasonic signal transmitting and receiving module

Abstract

The invention provides a preparation method of an ultrasonic water immersion probe and an ultrasonic signal transmitting and receiving module.The ultrasonic water immersion probe comprises a shell, an acoustic lens, a backing, a matching layer, a first connector, a second connector and the ultrasonic signal transmitting and receiving module, and the ultrasonic signal transmitting and receiving module is composed of a piezoelectric material layer and a metal layer; a matching layer is attached to one side of the ultrasonic signal transmitting and receiving module, and the side, attached with the matching layer, of the ultrasonic signal transmitting and receiving module is flush with the opening side of the shell; the backing tightly covers one side of a signal transmitting and receiving source of the ultrasonic signal transmitting and receiving module; the first connector is installed at the opening of the other side, opposite to the ultrasonic signal transmitting and receiving module, of the shell, the second connector is installed on the side wall of the shell, the first connector and the second connector are connected to the signal adapter plate in parallel and used for conducting electric signal interaction with the ultrasonic signal transmitting and receiving module, the technology is simple, and the performance is stable. The complexity of the working platform is simplified, and the use is simple and convenient.

Description

Technical Field

[0001] The embodiments of this specification relate to the field of ultrasonic non-destructive detection, and particularly to an ultrasonic immersion probe. Background Art

[0002] Existing ultrasonic point-focus immersion probes are mainly based on materials such as PZT, ALN, and lithium niobate. Limited by problems such as probe design and technology, ultra-high-frequency ultrasonic point-focus immersion probes are mainly controlled by foreign manufacturers such as PVA. Domestically developed ultrasonic point-focus immersion probes mainly focus on 25 MHz and below. Above 50 MHz, especially above 100 MHz, ultrasonic point-focus immersion probes are still blank.

[0003] There are mainly two ways in the existing probe design methods. One is to design the piezoelectric material and the converging lens at both ends of the delay block, and the other is to design the piezoelectric material and the converging lens on the same side of the delay block. For ultra-high-frequency ultrasonic point-focus immersion probes, the piezoelectric material is thin and the converging lens is small. When the piezoelectric material and the converging lens are designed on the same side, it faces great processing difficulties, and it is difficult to uniformly fabricate the piezoelectric material on the curved surface with the existing manufacturing methods, resulting in great difficulty in fabricating ultra-high-frequency ultrasonic point-focus immersion probes under this design, unstable performance, and easy to fail; while there is little research on the design of separating the piezoelectric material and the converging lens on both sides of the delay block.

[0004] In view of this, how to provide a transceiver integrated ultra-high-frequency ultrasonic point-focus immersion probe to solve the problems of difficult ignition in low-temperature environments and the risk of explosion in the liquid collection chamber has become an urgent technical problem to be solved. Summary of the Invention

[0005] In view of this, the embodiments of this specification provide an ultrasonic immersion probe. One or more embodiments of this specification also relate to a preparation method of an ultrasonic signal transmitting and receiving module to solve the technical defect that the existing ultrasonic point-focus immersion probe has a low frequency and cannot achieve clear ultrasonic scanning imaging.

[0006] According to the first aspect of the embodiments of this specification, an ultrasonic immersion probe is provided. The ultrasonic immersion probe includes a housing, an acoustic lens, a backing, a matching layer, a first connector, a second connector, and an ultrasonic signal transmitting and receiving module. Among them,

[0007] The ultrasonic signal transmitting and receiving module is composed of a piezoelectric material layer and a metal layer, and a matching layer is attached to one side of the ultrasonic signal transmitting and receiving module. The side of the ultrasonic signal transmitting and receiving module with the attached matching layer is flush with the opening side of the housing;

[0008] The backing tightly covers the signal transmitting and receiving source side of the ultrasonic signal transmitting and receiving module;

[0009] The first connector is installed at the opening on the opposite side of the housing relative to the ultrasonic signal transmitting and receiving module, the second connector is installed on the side wall of the housing, and the first connector and the second connector are connected to the signal transfer board in parallel for electrical signal interaction with the ultrasonic signal transmitting and receiving module.

[0010] In an alternative embodiment, the housing is made of metal for supporting and protecting the ultrasonic immersion probe.

[0011] In an alternative embodiment, the connector form of the first connector is UHF, and the connector form of the second connector is SMA.

[0012] In an alternative embodiment, the ultrasonic signal transmitting and receiving module is cylindrical.

[0013] In an alternative embodiment, the metal layer and the piezoelectric material of the ultrasonic signal transmitting and receiving module are in a sandwich stack shape, with the piezoelectric material in the middle and the metal layers on the upper and lower surfaces of the piezoelectric material. Among them, the metal layer includes a first metal layer and a second metal layer.

[0014] According to the second aspect of the embodiments of this specification, a method for manufacturing an ultrasonic signal transmitting and receiving module is provided. Using the ultrasonic immersion probe as described in the first aspect of the embodiments of this specification, it includes:

[0015] Select a silicon wafer bonded with a lithium niobate piezoelectric thin film as the substrate, and process the silicon wafer to prepare a lithium niobate piezoelectric thin film bonding layer;

[0016] By grinding and sandblasting the initial acoustic lens, a target acoustic lens is obtained;

[0017] Protect the flat end of the target acoustic lens with photoresist, deposit a matching layer on the focal plane of the acoustic lens using a target method, and after obtaining the matching layer, remove the photoresist on the surface of the matching layer using an acetone solution;

[0018] By processing the lithium niobate piezoelectric thin film bonding layer to form a eutectic alloy, bond the piezoelectric material and the acoustic lens based on the eutectic alloy, and remove the silicon substrate of the bonded piezoelectric material and acoustic lens by wet etching;

[0019] Prepare an upper electrode for the lithium niobate piezoelectric thin film, and use an ultrasonic wire bonding process to bond a gold wire to the electrode of the transducer.

[0020] In an alternative embodiment, the processing of the silicon wafer to prepare a lithium niobate piezoelectric thin film bonding layer includes:

[0021] The silicon wafer is ultrasonically cleaned, and a thin film is deposited on the cleaned silicon wafer by PVD method;

[0022] During the thin film preparation process, the deposited thin film is clamped in a tooling fixture to obtain a metal thin film, wherein the metal thin film is a metal thin film with a morphology;

[0023] By scribing the metal thin film, a silicon wafer with a target specification is obtained, and based on the silicon wafer, a lithium niobate piezoelectric thin film bonding layer is obtained.

[0024] This specification provides an ultrasonic immersion probe, which includes a housing, an acoustic lens, a backing, a matching layer, a first connector, a second connector, and an ultrasonic signal transmitting and receiving module. Among them, the ultrasonic signal transmitting and receiving module is composed of a piezoelectric material layer and a metal layer, and a matching layer is attached to one side of the ultrasonic signal transmitting and receiving module. The side of the ultrasonic signal transmitting and receiving module with the attached matching layer is flush with the opening side of the housing; the backing tightly covers the signal transmitting and receiving source side of the ultrasonic signal transmitting and receiving module; the first connector is installed at the opening on the other side of the housing opposite to the ultrasonic signal transmitting and receiving module, and the second connector is installed on the side wall of the housing, and the first connector and the second connector are connected to a signal transfer board in parallel for electrical signal interaction with the ultrasonic signal transmitting and receiving module.

[0025] Applying the transceiver integrated ultra-high frequency ultrasonic point focusing immersion probe provided by the embodiments of this specification, with the piezoelectric material and the concave surface arranged on both sides of the delay block, solves the problems of complex manufacturing process and unstable performance faced when the piezoelectric material and the concave surface are on the same side. Compared with the transmission type ultrasonic probe, it is simpler and more convenient to use, greatly simplifying the complexity of the working platform. Description of the Drawings

[0026] Figure 1 is a schematic structural diagram of an ultrasonic immersion probe provided by an embodiment of this specification;

[0027] Figure 2 is a schematic structural diagram of an ultrasonic signal transmitting and receiving module in an ultrasonic immersion probe provided by an embodiment of this specification;

[0028] Figure 3 is a schematic flow diagram of a preparation method of an ultrasonic signal transmitting and receiving module in an ultrasonic immersion probe provided by an embodiment of this specification;

[0029] Among them, there are an ultrasonic immersion probe - 100, a housing - 101, an acoustic lens - 102, a backing - 103, a matching layer - 104, a first connector - 105, a second connector - 106, an ultrasonic signal transmitting and receiving module - 107, a piezoelectric material layer - 108, a metal layer - 109, and a signal transfer board - 110. Specific embodiments

[0030] In the following description, numerous specific details are set forth in order to provide a thorough understanding of this specification. However, this specification can be implemented in many other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the connotation of this specification. Therefore, this specification is not limited by the specific embodiments disclosed below.

[0031] The terms used in one or more embodiments of this specification are for the purpose of describing specific embodiments only and are not intended to limit one or more embodiments of this specification. The singular forms "a", "the", and "said" used in one or more embodiments of this specification and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used in one or more embodiments of this specification refers to and includes any or all possible combinations of one or more of the associated listed items.

[0032] It should be understood that although the terms first, second, etc. may be used in one or more embodiments of this specification to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of one or more embodiments of this specification, the first can also be referred to as the second, and similarly, the second can also be referred to as the first. Depending on the context, the word "if" as used herein can be interpreted as "when" or "while" or "in response to determining".

[0033] In addition, it should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in one or more embodiments of this specification are all information and data that have been authorized by the user or fully authorized by all parties, and the collection, use, and processing of relevant data need to comply with the relevant laws, regulations, and standards of relevant countries and regions, and corresponding operation entrances are provided for users to choose to authorize or refuse.

[0034] In this specification, an ultrasonic immersion probe is provided, and this specification also relates to a method for preparing an ultrasonic signal transmitting and receiving module, aiming to solve the technical defect that the existing ultrasonic point - focused immersion probe has a low frequency and cannot achieve clear ultrasonic scanning imaging, which will be described in detail one by one in the following embodiments.

[0035] See Figure 1 , Figure 1 which is a schematic structural diagram of an ultrasonic immersion probe provided by an embodiment of this specification. As shown in Figure 1 , the ultrasonic immersion probe 100 includes a housing 101, an acoustic lens 102, a backing 103, a matching layer 104, a first connector 105, a second connector 106, and an ultrasonic signal transmitting and receiving module 107. Among them, the ultrasonic signal transmitting and receiving module 107 is composed of a piezoelectric material layer 108 and a metal layer 109, and a matching layer 104 is attached to one side of the ultrasonic signal transmitting and receiving module 107. The side of the ultrasonic signal transmitting and receiving module 107 with the matching layer 104 attached is flush with the opening side of the housing 101. See Figure 2 , Figure 2 which is a schematic structural diagram of the ultrasonic signal transmitting and receiving module in an ultrasonic immersion probe provided by an embodiment of this specification. Specifically, the metal layer 109 is usually composed of Au, and the materials used for the piezoelectric material layer 108 include but are not limited to lithium niobate, zinc oxide, PZT, AlN, etc. It is a signal transmitting and receiving source and plays a role in transmitting and receiving ultrasonic signals.

[0036] Among them, the matching layer 104 is composed of a polymer material and mainly plays a role in transmitting as much ultrasonic wave as possible from the acoustic lens 102 into the water and allowing the acoustic lens 102 to receive as much echo reflected from the water as possible.

[0037] The materials for the acoustic lens 102 include but are not limited to fused quartz, sapphire, etc., and play a role in transmitting and converging ultrasonic signals.

[0038] The backing 103 is tightly covered on the signal transmitting and receiving source side of the ultrasonic signal transmitting and receiving module 107; it should be noted that the materials used for the backing 103 here include but are not limited to epoxy resin, rubber, and play a damping role, allowing the ultrasonic wave energy to mainly converge towards the acoustic lens 102 side, which is used to improve the transmission efficiency of the signal transmitting and receiving source.

[0039] The first connector 105 is installed at the opening on the opposite side of the housing 101 facing the ultrasonic signal transmitting and receiving module 107. The second connector 106 is installed on the side wall of the housing 101. The first connector 105 and the second connector 106 are connected to the signal transfer board 110 in parallel for electrical signal interaction with the ultrasonic signal transmitting and receiving module 107. It should be noted that the first connector 105 and the second connector 106 are connected to the signal transfer board 110 in parallel to perform electrical signal interaction with the ultrasonic signal transmitting and receiving module 107 through the signal transfer board 110, so as to transmit the external excitation signal to the ultrasonic signal transmitting and receiving module 107 and transmit the echo signal received by the ultrasonic signal transmitting and receiving module 107 to the outside. In practical applications, the connectors of the first connector 105 and the second connector 106 include but are not limited to forms such as UHF, SMB, and SMA, which play the role of electrically connecting the probe to external devices.

[0040] In an embodiment of this specification, the housing 101 is columnar, which can be cylindrical or cubic. The housing 101 is made of metal and is used to support and protect the ultrasonic immersion probe 100.

[0041] In an embodiment of this specification, the connector form of the first connector 105 is UHF, and the connector form of the second connector 106 is SMA.

[0042] In an embodiment of this specification, the ultrasonic signal transmitting and receiving module 107 is cylindrical.

[0043] In an embodiment of this specification, the metal layer 109 of the ultrasonic signal transmitting and receiving module 107 and the piezoelectric material are in a sandwich stack shape, with the piezoelectric material in the middle and the metal layer 109 on the upper and lower surfaces of the piezoelectric material. Among them, the metal layer 109 includes a first metal layer and a second metal layer.

[0044] In an embodiment of this specification, a design structure of a 100 MHz ultrasonic point-focus immersion probe is provided, as Figure 2 shown, the metal layer 109 and the piezoelectric material layer 108 are in a sandwich stack design, with the piezoelectric material in the middle and the metal layer 109 on the upper and lower surfaces of the piezoelectric material respectively. The piezoelectric material is selected as a lithium niobate single crystal material with a thickness of 30 μm to 40 μm, and the metal layer 109 is made of Au material with a thickness of 50 nm to 150 nm.

[0045] In another embodiment of this specification, a design structure of a 300 MHz ultrasonic point-focus immersion probe is provided, as Figure 2As shown, the metal layer 109 and the piezoelectric material layer are designed in a sandwich stack. The piezoelectric material is in the middle, and the metal layers 109 are located on the upper and lower surfaces of the piezoelectric material respectively. The piezoelectric material is selected as a single crystal lithium niobate material with a thickness of 10 μm to 15 μm. The metal layers 109 are both made of Au material with a thickness of 50 nm to 150 nm.

[0046] In another embodiment of this specification, a design structure of a 500 MHz ultrasonic point-focusing immersion probe is provided. As Figure 2 shown, the metal layer 109 and the piezoelectric material are designed in a sandwich stack. The piezoelectric layer is in the middle, and the metal materials are located on the upper and lower surfaces of the piezoelectric material respectively. The piezoelectric material is selected as a single crystal lithium niobate material with a thickness of 6 μm to 9 μm. The metal layers 109 are both made of Au material with a thickness of 50 nm to 150 nm.

[0047] Applying the transceiver integrated ultra-high frequency ultrasonic point-focusing immersion probe provided by the embodiments of this specification, which adopts the design of piezoelectric material and concave split delay blocks on both sides, solves the problems of complex manufacturing process and unstable performance faced when the piezoelectric material and the concave surface are on the same side. Compared with the transmission ultrasonic probe, it is more simple and convenient to use, greatly simplifying the complexity of the working platform.

[0048] See Figure 3 , Figure 3 is a schematic flow chart of a preparation method for an ultrasonic signal transmitting and receiving module in an ultrasonic immersion probe provided by the embodiments of this specification. In the embodiments of this specification, the piezoelectric material is selected as a single crystal lithium niobate material, and its manufacturing process method and flow are as Figure 3 shown, specifically including the following steps.

[0049] Step S302: Select a silicon wafer bonded with a lithium niobate piezoelectric thin film as a substrate, and process the silicon wafer to prepare a lithium niobate piezoelectric thin film bonding layer.

[0050] Specifically, the processing of the silicon wafer to prepare a lithium niobate piezoelectric thin film bonding layer includes: ultrasonically cleaning the silicon wafer, and depositing a thin film on the cleaned silicon wafer by PVD; during the thin film preparation process, the deposited thin film is clamped in a tooling fixture to obtain a metal thin film, where the metal thin film is a metal thin film with a morphology; by dicing the metal thin film, a silicon wafer with a target specification is obtained, and based on the silicon wafer, a lithium niobate piezoelectric thin film bonding layer is obtained.

[0051] In practical applications, the preparation of the bonding layer of the lithium niobate piezoelectric thin film. A silicon wafer bonded with the lithium niobate piezoelectric thin film is selected as the substrate, and alcohol and acetone solutions are respectively used for ultrasonic cleaning. After cleaning, a gold thin film is deposited by the PVD method. During the thin film preparation process, the silicon wafer is clamped in a tooling fixture with a hard mask template, so that after the PVD process is completed and the mask fixture is removed, a metal thin film with the required morphology is directly obtained. After preparation, the silicon wafer is sliced to prepare a silicon wafer with a diameter of 1 mm.

[0052] Step S304: The target acoustic lens is obtained by grinding and sandblasting the initial acoustic lens.

[0053] In practical applications, when preparing the acoustic lens, one side of the acoustic lens needs to be ground into a conical surface and roughened by sandblasting. The method of grinding and polishing the flat part material of the acoustic lens is to polish it into a crystal plane, and its surface roughness is required to be less than 1 nm. The central part of the conical end of the acoustic lens needs to be ground and polished with a grinding rod to form a focusing surface, and the roughness of the focusing surface after polishing is required to be less than 1 nm.

[0054] Step S306: Protect the flat end of the target acoustic lens with photoresist, deposit a matching layer on the focusing surface of the acoustic lens by the target method, and after obtaining the matching layer, use acetone solution to remove the photoresist on the surface of the matching layer.

[0055] In practical applications, the flat end face of the acoustic lens is protected with photoresist, and a matching layer is deposited on the focusing surface of the acoustic lens by the PVD or CVD method. After the matching layer is prepared, the photoresist on the flat end face of the acoustic lens is removed completely with acetone solution.

[0056] Step S308: By processing the bonding layer of the lithium niobate piezoelectric thin film, a eutectic alloy is formed. Based on the eutectic alloy, the piezoelectric material and the acoustic lens are bonded, and the silicon substrate of the bonded piezoelectric material and acoustic lens is removed by wet etching.

[0057] In practical applications, for the preparation of the acoustic lens bonding layer, alcohol and acetone solutions are respectively selected for ultrasonic cleaning to clean the acoustic lens. After cleaning, a photoresist protection layer is prepared on the focusing surface of the acoustic lens by spray coating, and a gold thin film is deposited by the PVD method. After the bonding layer is prepared, the photoresist on the focusing surface of the acoustic lens is removed completely with acetone solution.

[0058] The bonding method of the piezoelectric material and the acoustic lens is to closely bond the bonding layers of the piezoelectric material and the acoustic lens together. During the bonding process, in order to ensure close contact between the bonding layers, a pressure of 1 to 2 kg can be applied. After the bonding layers are closely bonded, the closely bonded piezoelectric material and acoustic lens are placed in a vacuum or inert gas environment, and the bonding layer is heated to form a eutectic alloy, thereby completing the bonding of the piezoelectric material and the acoustic lens.

[0059] The silicon substrates of the bonded piezoelectric material and the acoustic lens are removed by wet etching, including: removing the silicon substrate by wet etching method, using 25% TMAH aqueous solution to etch silicon at 80 °C until it is completely removed.

[0060] Step S310: Prepare the upper electrode of the lithium niobate piezoelectric thin film, and use the ultrasonic wire bonding process to bond the gold wire to the electrodes of the transducer.

[0061] In practical applications, the method for preparing the upper electrode of the lithium niobate piezoelectric thin film is: depositing a gold film by PVD method, and clamping the transducer in a tooling fixture with a hard mask template, so that after the PVD process is completed and the mask fixture is removed, a metal electrode with the required morphology can be directly obtained.

[0062] After obtaining the metal electrode, lead preparation is carried out. Among them, the method for lead preparation here is: using the ultrasonic wire bonding process to bond the gold wire to the upper and lower electrodes of the transducer respectively.

[0063] The above is a schematic solution for the preparation method of an ultrasonic signal transmitting and receiving module in this embodiment. It should be noted that the technical solution of the preparation method of this ultrasonic signal transmitting and receiving module belongs to a part of the technical solution of the above ultrasonic immersion probe, and belongs to the same concept. For the details not described in detail in the technical solution of the preparation method of the ultrasonic signal transmitting and receiving module, reference can be made to the description of the technical solution of the above ultrasonic immersion probe.

[0064] An embodiment of this specification also provides a computer-readable storage medium, which stores computer-executable instructions. When the computer-executable instructions are executed by a processor, the steps of the above preparation method of an ultrasonic signal transmitting and receiving module are implemented.

[0065] The above describes a specific embodiment of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be executed in a different order from that in the embodiment and still achieve the desired result. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired result. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0066] It should be noted that, for the foregoing method embodiments, for the sake of simplicity of description, they are all expressed as a series of action combinations. However, those skilled in the art should know that the embodiments of this specification are not limited by the described action sequence, because according to the embodiments of this specification, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily essential to the embodiments of this specification.

[0067] In the above embodiments, the descriptions of each embodiment have their own focuses. For the parts not detailed in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0068] The preferred embodiments of this specification disclosed above are only used to help explain this specification. The alternative embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. Obviously, according to the content of the embodiments of this specification, many modifications and changes can be made. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the embodiments of this specification, so that those skilled in the art can understand and utilize this specification well. This specification is only limited by the claims and their full scope and equivalents.

Claims

1. An ultrasonic immersion probe, characterized in that, The ultrasonic immersion probe includes a housing, an acoustic lens, a backing, a matching layer, a first connector, a second connector, and an ultrasonic signal transmitting and receiving module. Among them, the ultrasonic signal transmitting and receiving module is composed of a piezoelectric material layer and a metal layer, and a matching layer is attached to one side of the ultrasonic signal transmitting and receiving module. The side of the ultrasonic signal transmitting and receiving module with the attached matching layer is flush with the opening side of the housing; the backing tightly covers the signal transmitting and receiving source side of the ultrasonic signal transmitting and receiving module; the first connector is installed at the opening on the other side of the housing opposite to the ultrasonic signal transmitting and receiving module, the second connector is installed on the side wall of the housing, and the first connector and the second connector are connected to the signal transfer board in parallel for electrical signal interaction with the ultrasonic signal transmitting and receiving module.

2. The ultrasonic immersion probe according to claim 1, wherein The housing is made of metal and is used to support and protect the ultrasonic immersion probe.

3. The ultrasonic immersion probe according to claim 1, characterized in that, The connector form of the first connector is UHF, and the connector form of the second connector is SMA.

4. The ultrasonic immersion probe according to claim 1, wherein The ultrasonic signal transmitting and receiving module is cylindrical.

5. An ultrasonic immersion probe according to claim 1 or 4, characterized in that, The metal layer of the ultrasonic signal transmitting and receiving module and the piezoelectric material are in a sandwich stack shape, with the piezoelectric material in the middle and the metal layer on the upper and lower surfaces of the piezoelectric material. Among them, the metal layer includes a first metal layer and a second metal layer.

6. A preparation method of an ultrasonic signal transmitting and receiving module, using the ultrasonic immersion probe as described in claim 1, characterized in that, Including: Select a silicon wafer bonded with a lithium niobate piezoelectric thin film as the substrate, and process the silicon wafer to prepare a lithium niobate piezoelectric thin film bonding layer; Obtain the target acoustic lens by grinding and sandblasting the initial acoustic lens; Protect the flat end of the target acoustic lens with photoresist, deposit a matching layer on the focal plane of the acoustic lens by using a target method, and after obtaining the matching layer, use acetone solution to remove the photoresist on the surface of the matching layer; Process the lithium niobate piezoelectric thin film bonding layer to form a eutectic alloy, bond the piezoelectric material and the acoustic lens based on the eutectic alloy, and remove the silicon substrate of the bonded piezoelectric material and acoustic lens by wet etching; Prepare the upper electrode of the lithium niobate piezoelectric thin film, and use ultrasonic wire bonding technology to bond the gold wire to the electrode of the transducer.

7. The method according to claim 6, characterized in that, The processing of the silicon wafer to prepare the lithium niobate piezoelectric thin film bonding layer includes: Ultrasonically clean the silicon wafer, and use PVD method to deposit a film on the cleaned silicon wafer; During the film preparation process, the deposited film is clamped in a tooling fixture to obtain a metal film, where the metal film is a metal film with a morphology; Obtain a silicon wafer with a target specification by dicing the metal film, and based on the silicon wafer, obtain a lithium niobate piezoelectric thin film bonding layer.

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