WO2019119178A1

WO2019119178A1 - Mode conversion ultrasonic transducer and method for manufacturing same

Info

Publication number: WO2019119178A1
Application number: PCT/CN2017/116843
Authority: WO
Inventors: 郑海荣; 郭瑞彪; 钱明; 李永川; 黄继卿
Original assignee: 深圳先进技术研究院
Priority date: 2017-12-18
Filing date: 2017-12-18
Publication date: 2019-06-27

Abstract

The present invention is applicable to the technical field of ultrasonic transduction, and discloses a mode conversion ultrasonic transducer and a method for manufacturing same. The mode conversion ultrasonic transducer comprises a housing, a mode conversion piezoelectric sheet, and a circuit board; the mode conversion piezoelectric sheet is provided in the housing; the circuit board is connected to the mode conversion piezoelectric sheet; the mode conversion piezoelectric sheet comprises a plurality of piezoelectric blocks; one side of the mode conversion piezoelectric sheet is provided with a slot that allows insertion of the circuit board; two sides of the slot are provided with electrodes of the piezoelectric blocks; the circuit board is inserted into the slot and connected to the electrodes. The manufacturing method is used for manufacturing the mode conversion ultrasonic transducer. According to the mode conversion ultrasonic transducer and the method for manufacturing same provided in the present invention, the electrodes of the piezoelectric blocks are led out by using the circuit board to ensure consistency of impedance of each piezoelectric block, and the occurrence of grating lobes is avoided by means of mode conversion, thereby obtaining good sound field focusing performance.

Description

Mode conversion ultrasonic transducer and manufacturing method thereof

Technical field

The invention belongs to the field of ultrasonic transduction technology, and in particular relates to a mode conversion ultrasonic transducer and a manufacturing method thereof.

Background technique

The core of the area array ultrasound system is the two-dimensional array ultrasonic transducer. The difficulty of the large-scale two-dimensional array ultrasonic transducer is how to ensure that the array element vibration mode is simple, each array element is consistent, and the array element lead method is simple. Reliable, transducer field focus deflection does not produce severe side lobes and grating lobes. A two-dimensional array probe usually consists of one to thousands of individual piezoelectric elements, and each array element has a very small length and width. How to ensure the consistency of each element and make each piezoelectric element Electrode extraction is a problem. The traditional scheme is to connect the positive and negative poles of the piezoelectric array element directly to the external cable. When the number of array elements of the ultrasonic transducer is relatively large, if each array element is independently wired by using the full wiring method, each array element is made. Both generate independent pulse signals, which are unreliable due to unreliable electrodes of the piezoelectric sheets, and direct soldering does not guarantee the uniformity of each array element lead. Moreover, the conventional preparation scheme is difficult to ensure that the array spacing is smaller than the minimum interval required to generate side lobes, and there is no guarantee that the ultrasonic transducer can obtain a good focus deflection sound field.

technical problem

SUMMARY OF THE INVENTION It is an object of the present invention to overcome the deficiencies of the prior art described above and to provide a mode-switched ultrasonic transducer and a method of fabricating the same that can obtain a good focus deflection sound field.

Technical solution

The technical solution of the present invention is: a mode-switching ultrasonic transducer comprising a housing, a mode-switching piezoelectric sheet, and a circuit board, wherein the mode-switching piezoelectric sheet is disposed in the housing, and the circuit board is connected to the a mode conversion piezoelectric sheet; the mode conversion piezoelectric sheet includes a plurality of piezoelectric blocks, and one side of the mode conversion piezoelectric sheet is provided with a slot for inserting the circuit board, both sides of the slot As an electrode of the piezoelectric block, the circuit board is inserted into the socket and is in contact with the electrode.

Optionally, one side of the circuit board is provided with a positive lead, and the other side of the circuit board is provided with a negative lead, and the circuit board is connected with a cable or a bus bar.

Optionally, the slot is provided with at least two slots, each of the slots is disposed in parallel and each of the piezoelectric blocks is divided into at least three rows, and two sides of the slot are respectively a positive conductive layer and a negative conductive a layer, the positive conductive layer is in contact with one side of a row of the piezoelectric block, and the negative conductive layer is connected to a side of the adjacent one of the piezoelectric blocks, and the piezoelectric block is in the same row. The opposite sides are respectively a positive conductive layer and a negative conductive layer.

Optionally, a bottom surface of the mode conversion piezoelectric sheet is provided with a matching layer.

Optionally, the piezoelectric block is provided with a plurality of rows and columns, and the piezoelectric blocks between adjacent columns are connected by an insulator.

Optionally, the circuit board is a flexible circuit board, and/or the housing is made of a magnetic compatible material.

Optionally, the housing includes a housing and a top cover connected to the housing, the mode switching piezoelectric piece is disposed in a flat bottom surface of the housing, and the circuit board is perpendicular to the mode conversion piezoelectric chip insertion In the slot, the cable is passed through the top cover and connected to the positive lead and the negative lead on both sides of the circuit board.

The embodiment of the invention further provides a method for manufacturing a mode-switched ultrasonic transducer, comprising the following steps:

Preparing a housing, a circuit board, and a mode conversion piezoelectric sheet having a socket and having piezoelectric block electrodes on both sides of the socket;

Locating the mode conversion piezoelectric sheet in the housing;

A circuit board is inserted into the slot of the mode conversion piezoelectric piece to connect the circuit board to the electrodes of the piezoelectric block.

Optionally, preparing the mode conversion piezoelectric sheet comprises the following steps:

Forming a piezoelectric sheet, opening a first partition in a first direction on a front surface of the piezoelectric sheet, filling a conductive material in the first partition; and opening a front surface in a second direction on a front surface of the piezoelectric sheet a second compartment intersecting the first compartments, wherein the second compartments are filled with an insulator;

Removing a material of a set thickness of the back surface of the piezoelectric sheet, and providing a matching layer on the back surface of the piezoelectric sheet;

A slot is disposed on the conductive material along the first spacer such that the conductive material is separated by the slot into a positive conductive layer and a negative conductive layer attached to sides of the piezoelectric block of adjacent rows.

Optionally, the two sides of the circuit board are respectively provided with a plurality of positive lead wires and a plurality of negative electrode leads. When the circuit board is inserted into the slot, each of the positive lead wires respectively passes through a conductive material and each of the same row The positive electrode conductive layers on one side of the piezoelectric block are in contact with each other, and each of the negative electrode leads is respectively connected to the negative electrode conductive layer on one side of each of the piezoelectric blocks in another row through a conductive material; On the circuit board.

Optionally, the circuit board is a flexible circuit board.

Optionally, the mode-switching piezoelectric sheet is placed in a flat housing at the bottom, and the circuit board is inserted into the slot before the mode-switching piezoelectric sheet is loaded into the housing or after being loaded into the housing.

Beneficial effect

The invention provides a mode-switching ultrasonic transducer and a manufacturing method thereof, wherein an electrode of a piezoelectric block is taken out in a width direction by a circuit board (double-sided flexible circuit board) to ensure uniformity of impedance of each piezoelectric block, With the mode switching method, the grating lobes do not appear, so that good sound field focusing performance is obtained.

DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings to be used in the embodiments will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without paying any creative work.

1 is a schematic perspective view of a mode-switched ultrasonic transducer according to an embodiment of the present invention;

2 is a perspective exploded view of a mode-switched ultrasonic transducer according to an embodiment of the present invention;

3 is a perspective exploded partial cross-sectional view of a mode-switched ultrasonic transducer according to an embodiment of the present invention;

4 is a perspective view of a piezoelectric sheet in a method for manufacturing a mode-switched ultrasonic transducer according to an embodiment of the present invention;

Figure 5 is a perspective view of the piezoelectric sheet of Figure 4 after the first compartment is opened;

Figure 6 is a perspective view of the piezoelectric sheet of Figure 5 after filling the conductive material in the first compartment;

Figure 7 is a perspective view of the piezoelectric sheet of Figure 6 after the second compartment is opened;

Figure 8 is a perspective view of the piezoelectric sheet of Figure 7 after the second spacer is filled with an insulator;

Figure 9 is a perspective view of the piezoelectric sheet of Figure 8 after removing the back thickness setting material;

Figure 10 is a perspective view showing the matching layer on the back side of the piezoelectric sheet of Figure 9;

Figure 11 is a perspective view showing the mode conversion piezoelectric sheet formed after the slot is disposed on the front surface of the piezoelectric sheet of Figure 10;

Figure 12 is a perspective view of the circuit board in the embodiment;

Figure 13 is a perspective view of the circuit board in the embodiment;

Fig. 14 is a perspective view showing the circuit board inserted into the slot of the mode conversion piezoelectric sheet in the embodiment.

Embodiments of the invention

The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

It is to be noted that when an element is referred to as being "fixed" or "in" another element, it can be directly on the other element or the central element. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or the central element.

It should also be noted that the left, right, upper, lower, and the like orientations in the embodiments of the present invention are merely relative concepts or referenced to the normal use state of the product, and should not be considered as limiting. .

As shown in FIG. 1 to FIG. 3, a mode conversion ultrasonic transducer provided by an embodiment of the present invention includes a casing 1, a mode conversion piezoelectric sheet 2, a circuit board 3 and a cable 4, and a mode conversion piezoelectric sheet 2 Provided in the casing 1, the circuit board 3 is connected to the mode conversion piezoelectric sheet 2, and the cable 4 can be indirectly connected to the circuit board 3 directly or through a busbar circuit board (concentrator). The mode-switching piezoelectric sheet 2 may include a plurality of matrix-arranged piezoelectric blocks 20, one side of which is provided with a slot 201 for inserting the circuit board 3, and the two sides of the slot 201 are piezoelectric The electrodes of the block 20 are provided with electrode leads on both sides of the circuit board 3. The circuit board 3 is inserted into the slot 201 and is in contact with the electrodes of the piezoelectric block 20. The mode-switching piezoelectric sheet 2 can be made of piezoelectric ceramics, and the piezoelectric ceramic has many characteristics of vibration modes, and the two-dimensional array ultrasonic transducer is designed by mode conversion of the piezoelectric ceramics, and each array element (pressure) The electrode of the electric block 20) is taken out in the width direction by the circuit board 3 (double-sided flexible circuit board) to ensure the uniformity of the impedance of each array element (piezoelectric block 20), and the piezoelectric composite material is set by means of mode conversion. The electrode is in the width direction (the width of this direction can be set less than the width required to produce the acoustic parameters of the grating lobe, which can be set according to the actual situation), but the direction of the acoustic radiation we are concerned with is the thickness direction of the piezoelectric material. This ensures that no grating lobes are present and a good sound field focusing performance is obtained.

Optionally, one side of the same slot 201 is the positive conductive layer 211 of the same row of piezoelectric blocks 20, and the other side of the same slot 201 is the negative conductive layer 212 of the adjacent row of piezoelectric blocks 20. One side of the circuit board 3 is provided with a plurality of sets of positive electrode leads 31 which are evenly spaced, and the other side of the circuit board 3 is provided with a plurality of sets of negative electrode leads 32 which are evenly spaced. Each set of positive electrode leads 31 is connected to the positive electrode conductive layer 211 on one side of one of the piezoelectric blocks 20 directly or through a conductive connection (for example, a conductive paste). Each set of negative electrode leads 32 is connected to the negative electrode conductive layer 212 on one side of a piezoelectric block 20 directly or through a conductive connection such as a conductive paste. The circuit board 3 can convert the piezoelectric sheet 2 perpendicular to the mode and insert it into the slot 201. The adjacent piezoelectric block 20, the positive electrode conductive layer 211, and the negative electrode conductive layer 212 in the same row are each separated by an insulator 220, and the insulator 220 may be provided in a plurality of columns. The insulator 220 may be an insulating polymer or air. It should be noted that the rows and columns in this embodiment are only relative concepts and should not be cleaved to have a limiting effect.

Optionally, the slot 201 is provided with at least two slots, and the slots 201 are disposed in parallel and divide each piezoelectric block 20 into at least three rows. The two sides of the slot 201 are respectively separated from the positive conductive layer 211 and the negative pole. The conductive layer 212, the positive conductive layer 211 on one side of the slot 201 is in contact with one side of the row of piezoelectric blocks 20, and the negative conductive layer 212 on the other side of the slot 201 is adjacent to the other adjacent row of piezoelectric blocks 20. Contact each other. Except for the edge piezoelectric block 200, the same row of piezoelectric blocks 20 have opposite positive side conductive layers 211 and negative electrode conductive layers 212, and the piezoelectric blocks 20 can be arranged in a matrix, in the row direction by the slots. 201 is spaced apart from the electrode conductive layer and is separated and connected by the insulator 220 in the direction of the column.

Alternatively, the bottom surface of the mode conversion piezoelectric sheet 2 is provided with a matching layer 5. The thickness of the matching layer 5 satisfies the thickness required for acoustic performance. The function of the matching layer 5 is to ensure that the acoustic energy can be output more efficiently on the one hand, and on the other hand, as a substrate of the composite material (mode-switching piezoelectric sheet 2), supporting the composite material after the spacers divide the electrodes. Optionally, an acoustic lens may also be disposed on the surface of the matching layer 5, and the acoustic lens may increase the focusing effect of the probe.

In this embodiment, the mode-switching piezoelectric sheet 2 may have a rectangular shape, the piezoelectric block 20 is provided with a plurality of rows and columns, and the piezoelectric blocks 20 between adjacent columns are connected and separated by the insulator 220.

Optionally, the circuit board 3 in this embodiment may be a flexible circuit board or a general PCB.

Alternatively, the housing 1 may be made of a magnetic compatible material such as plastic, bakelite or the like.

Optionally, the housing 1 includes a housing 11 and a top cover 12 connected to the housing 11, the housing 11 has a flat bottom surface, the mode conversion piezoelectric sheet 2 is disposed in the flat bottom surface of the housing 11, and the circuit board 3 is vertically switched. The chip 2 is inserted into the slot 201, and the cable 4 is disposed on the top cover 12 and connected to the positive lead 31 and the negative lead 32 on both sides of the circuit board 3, and the arrangement is regular. The casing 1 may have a rectangular parallelepiped shape, a cylinder or the like.

As shown in FIG. 1 to FIG. 3, an embodiment of the present invention further provides a method for manufacturing a mode-switched ultrasonic transducer, which can be used to manufacture the above-described mode-switched ultrasonic transducer, comprising the following steps:

Preparing a housing 1, a circuit board 3, a cable 4 and a mode switching piezoelectric sheet 2 having a socket 201 and having electrodes on both sides of the socket 201 as piezoelectric blocks 20;

Placing the mode conversion piezoelectric sheet 2 in the housing 1;

Inserting the circuit board 3 into the slot 201 of the mode conversion piezoelectric sheet 2, and connecting the circuit board 3 to the electrodes of the piezoelectric block 20;

The cable 4 is connected to the circuit board 3.

Optionally, preparing the mode conversion piezoelectric sheet 2 comprises the following steps:

Referring to FIGS. 3 to 8, the piezoelectric sheet 210 is prepared, and a plurality of first spacers 231 are opened in the first direction on the front surface of the piezoelectric sheet 210. The interval and depth of the first spacers 231 may be acoustically tuned by the transducer. The characteristic determines that the cut M-row piezoelectric ceramic column is determined by the set matrix matrix, and the conductive material 230 (conductive polymer) is filled in the first partition 231; the conductive polymer can be connected to the M-row ceramic column on the one hand. On the other hand, it can be used to prepare electrodes (positive electrode conductive layer 211 and negative electrode conductive layer 212) of a piezoelectric material. Through this electrode (positive electrode conductive layer 211 and negative electrode conductive layer 212), an excitation can be applied to the piezoelectric material to stimulate the piezoelectric sheet 210 to generate an ultrasonic radiation force. A plurality of second spacers 241 intersecting the first spacers 231 are formed in the second direction on the front surface of the piezoelectric sheet 210. The interval and depth of the second spacers 241 may be determined by the acoustic characteristics of the transducer, and the cut N The column piezoelectric ceramic column is determined by the matrix of the array elements, and the second spacer 241 is filled with an insulator 220 (insulating polymer); the insulating polymer can be connected to the N columns of ceramic columns on the one hand, and the suppression array on the other hand. The crosstalk between the elements (piezoelectric block 20) is used to separate the N columns of electrodes (conductor 230) to ensure each element of the matrix of the piezoelectric ceramic column of the M*N (piezoelectric block) 20) There are independent positive and negative electrode faces (positive electrode conductive layer 211 and negative electrode conductive layer 212). The piezoelectric material (piezoelectric block 20) can be excited by this electrode (positive and negative electrode faces) to stimulate the piezoelectric sheet 210 to generate ultrasonic radiation. The depths of the first compartment 231 and the second compartment 241 may be equal.

Referring to FIG. 9, the material of the set thickness of the back surface of the piezoelectric sheet 210 is removed, and the piezoelectric sheet 210 is at least grounded to the bottom surface of the first partition 231 and the second partition 241, as shown in FIG. A matching layer 5 is disposed on the back surface of the piezoelectric sheet 210. The matching layer 5 functions on the one hand to ensure that the acoustic energy can be output more efficiently; on the other hand, as a base of the composite material (mode-switching piezoelectric sheet 2), divided in the compartment Supporting the composite material after the electrode;

As shown in FIG. 11, a slot 201 is disposed on the conductive member 230 along the first spacer 231, so that the conductive member 230 is separated by the slot 201 as the positive conductive layer 211 attached to the side of the piezoelectric block 20 of the adjacent row and Negative electrode conductive layer 212.

Alternatively, the setting of the slot 201 may include the steps of dividing the conductive polymer filled in the first spacer 231 along the middle line to form the slot 201, the cut slot 201 being narrower than the first spacer 231 and in the depth direction The conductive polymer filled in the first compartment 231 is cut through. Thus, the conductive polymer filled in the first spacer 231 can be divided into two portions as the electrodes of the adjacent contact piezoelectric blocks 20 (the positive electrode conductive layer 211 and the negative electrode conductive layer 212).

Optionally, as shown in FIG. 12 to FIG. 14 , the two sides of the circuit board 3 are respectively provided with a plurality of positive lead wires 31 and a plurality of negative electrode leads 32. The circuit board 3 is a double-sided circuit board, and the circuit board 3 is inserted into the slot 201. Each of the positive electrode leads 31 is electrically connected to the positive electrode conductive layer 211 on the side of each piezoelectric block 20 in the same row, and each of the negative electrode leads 32 passes through the conductive material or directly to each of the piezoelectric blocks 20 in the other row. The negative electrode conductive layer 212 on one side is in contact. The conductive material may be a conductive paste or the like.

Alternatively, the circuit board 3 may be a double-sided flexible circuit board 3 or a normal double-sided PCB board. The positive and negative electrode leads of the piezoelectric sheet 210 are provided by the double-sided circuit board 3, and the corresponding electrode lead is provided on both sides of the circuit board 3. If the electrode on one side is defined as the positive electrode, the electrode corresponding to the surface is defined as the negative electrode. The double-sided circuit board 3 is installed once in the M-cut card slot, and the circuit board 3 and the card slot have a small gap fit or an interference fit, have a certain mechanical contact, and then use the conductive material to the circuit board 3 The electrode lead and the electrode conductive layer of the array element (the positive electrode conductive layer 211 and the negative electrode conductive layer 212) are bonded. In this way, on the one hand, the positioning function can be achieved, and on the one hand, the conductivity of the electrode lead and the electrode conductive layer can be ensured. Finally, the electrode conductive layer of each array element can be leaded in this way, and a positive and negative electric signal is applied on both sides of the circuit board 3 to energize each array element.

Alternatively, the mode-switching piezoelectric sheet 2 may be placed in a flat housing 1 at the bottom, and the circuit board 3 is inserted into the housing 1 before the mode-switching piezoelectric sheet 2 is inserted into the housing 1 or inserted into the housing 1 In the slot 201, the electrode leads on both sides of the circuit board 3 are connected to the electrode conductive layers on both sides of the slot 201, and the positive and negative signal lines are connected on both sides of the circuit board 3. Of course, an additional circuit board (bus bar) can be used to connect to each circuit board 3, and the cable 4 can be connected to the flexible circuit board 3. In this embodiment, the mode-switching piezoelectric sheet 2 (piezoelectric ceramic) of the M*N array in which the circuit board 3 is mounted is mounted in the casing 11, and the bottom surface of the matching layer 5 is mounted on the same plane pressure as the bottom surface of the casing 11. On the one hand, the flatness of the transducer can be ensured, thereby ensuring the consistency of the prepared batch of probes; on the other hand, the probe array element can be protected from deformation and internal damage. The outer casing 11 package and circuit leads are fabricated as the final mode-converted two-dimensional array ultrasonic transducer.

A mode-switching ultrasonic transducer and a manufacturing method thereof are provided by the embodiments of the present invention, and the piezoelectric ceramic has many characteristics of vibration modes, and the vibration mode of the desired acoustic radiation direction is selected, and the desired acoustic radiation direction is designed. Selecting the pure vibration mode, the sound radiation direction A is the thickness direction of the mode conversion piezoelectric sheet 2, the electrode application direction B is perpendicular to the sound radiation direction A, and the electrodes of each array element are taken out by the flexible circuit board 3, thereby solving the unreliable welding. The problem is to ensure the consistency of the impedance of each element. By means of mode conversion, the piezoelectric composite material can be prepared such that the spacing between the ceramic columns is less than a certain value, and that the grating lobes are not present, a good focusing performance can be obtained. Moreover, by preparing the mode switching electrode faces (positive electrode conductive layer 211 and negative electrode conductive layer 212), the card slot and the double-sided circuit board 3 leads, the two-dimensional array can be fully wired, which solves the problem that the conventional ultrasonic welding is unreliable and consumes. The problem of long duration and high cost is more suitable for mass production of multi-array two-dimensional array ultrasonic transducers.

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions or improvements made within the spirit and scope of the present invention should be included in the scope of the present invention. Inside.

Claims

A mode switching ultrasonic transducer, comprising: a housing, a mode conversion piezoelectric sheet, a circuit board, the mode conversion piezoelectric sheet is disposed in the housing, and the circuit board is connected to the mode conversion a piezoelectric sheet; the mode conversion piezoelectric sheet includes a plurality of piezoelectric blocks, one side of the mode conversion piezoelectric sheet is provided with a slot for inserting the circuit board, and both sides of the slot are An electrode of the piezoelectric block, the circuit board being inserted into the socket and being in contact with the electrode.
A mode switching ultrasonic transducer according to claim 1, wherein one side of said circuit board is provided with a positive lead, and the other side of said circuit board is provided with a negative lead, said circuit board being wired Cable or manifold.
A mode-switching ultrasonic transducer according to claim 1, wherein said slot is provided with at least two, each of said slots being disposed in parallel and separating each of said piezoelectric blocks into at least three rows The two sides of the slot are respectively a positive conductive layer and a negative conductive layer, the positive conductive layer is connected to one side of one row of the piezoelectric block, and the negative conductive layer is pressed with another adjacent row One side of the electric block is connected, and the piezoelectric blocks of the same row have opposite positive side conductive layers and negative electrode conductive layers.
A mode-switched ultrasonic transducer according to claim 1, wherein a bottom surface of said mode-switching piezoelectric sheet is provided with a matching layer.
A mode-switched ultrasonic transducer according to claim 1, wherein said piezoelectric block is provided with a plurality of rows and columns, and said piezoelectric blocks between adjacent columns are connected by an insulator.
A mode-switched ultrasonic transducer according to claim 1, wherein said circuit board is a flexible circuit board, and/or said housing is made of a magnetic compatible material.
A mode-switching ultrasonic transducer according to claim 2, wherein said housing comprises a housing and a top cover connected to said housing, said mode switching piezoelectric sheet being disposed on said housing In the bottom surface, the circuit board is vertically inserted into the slot, and the cable is inserted through the top cover and connected to the positive lead and the negative lead on both sides of the circuit board.
A method for manufacturing a mode-switching ultrasonic transducer, comprising the steps of:

Preparing a housing, a circuit board, and a mode conversion piezoelectric sheet having a socket and having piezoelectric block electrodes on both sides of the socket;

Locating the mode conversion piezoelectric sheet in the housing;

A circuit board is inserted into the slot of the mode conversion piezoelectric piece to connect the circuit board to the electrodes of the piezoelectric block.
A method of manufacturing a mode-switched ultrasonic transducer according to claim 8, wherein the preparing the mode-switching piezoelectric sheet comprises the steps of:

Forming a piezoelectric sheet, opening a first partition in a first direction on a front surface of the piezoelectric sheet, filling a conductive material in the first partition; and opening a front surface in a second direction on a front surface of the piezoelectric sheet a second compartment intersecting the first compartments, wherein the second compartments are filled with an insulator;

Removing a material of a set thickness of the back surface of the piezoelectric sheet, and providing a matching layer on the back surface of the piezoelectric sheet;

A slot is disposed on the conductive material along the first spacer such that the conductive material is separated by the slot into a positive conductive layer and a negative conductive layer attached to sides of the piezoelectric block of adjacent rows.
The method of manufacturing a mode-switched ultrasonic transducer according to claim 9, wherein the two sides of the circuit board are respectively provided with a plurality of positive electrode leads and a plurality of negative electrode leads, and the circuit board is inserted in the same In the case of the slot, each of the positive lead wires is respectively connected to the positive conductive layer on one side of each of the piezoelectric blocks in the same row through a conductive material, and each of the negative lead wires respectively passes through the conductive material and each of the other rows. The negative conductive layer on one side of the piezoelectric block is connected; a cable is connected to the circuit board.
A method of manufacturing a mode-switched ultrasonic transducer according to claim 10, wherein said circuit board is a flexible circuit board.
A method of manufacturing a mode-switched ultrasonic transducer according to claim 10, wherein the mode-switching piezoelectric sheet is placed in a flat housing at the bottom, and the circuit board converts the piezoelectric sheet in the mode. Insert into the slot before loading the housing or after loading the housing.