Two-dimensional ultrasonic transducer and method of manufacturing the same

Abstract

The application provides a two-dimensional ultrasonic transducer, which comprises two flexible circuit boards and an acoustic-electric conversion element. The two flexible circuit boards are arranged on a first dimension and a second dimension respectively. The acoustic-electric conversion element is arranged between the two flexible circuit boards. Opposite sides of the acoustic-electric conversion element are respectively provided with a conductive layer and a matching layer. The conductive layer is connected with one of the two flexible circuit boards on the first dimension, and the matching layer is connected with the other of the two flexible circuit boards on the second dimension. The acoustic-electric conversion element and the conductive layer are divided into N equal parts on the second dimension, and the acoustic-electric conversion element and the matching layer are divided into M equal parts on the first dimension, so as to form MxN array elements, wherein M and N are positive integers greater than 1.

Description

Technical Field

[0001] This invention relates to an ultrasonic transducer and its manufacturing method, and more particularly to a two-dimensional ultrasonic transducer and its manufacturing method. Background Technology

[0002] Traditional ultrasonic transducers (or probes) use one-dimensional or two-dimensional acoustic wave generating units (or array elements) to emit ultrasonic signals and receive reflected ultrasonic signals corresponding to the emitted ultrasonic signals. Because traditional acoustic wave generating units are electrically connected to a circuit board via multiple solder wires, a large number of soldering areas need to be reserved on the circuit board, making the assembly process complex. Consequently, the number of usable array elements is limited, preventing an effective increase in the number of channels. Furthermore, the assembled acoustic wave generating unit is large, which also affects the overall requirements of the ultrasonic transducer.

[0003] Therefore, it is necessary to design a novel two-dimensional ultrasonic transducer and its manufacturing method to overcome the above-mentioned defects. Summary of the Invention

[0004] The purpose of this invention is to provide a two-dimensional ultrasonic transducer and its manufacturing method, which can produce a two-dimensional ultrasonic transducer with small size and many channels, thereby improving the overall requirements of two-dimensional ultrasonic transducers.

[0005] To achieve the above objectives, the present invention provides a two-dimensional ultrasonic transducer, comprising: two flexible circuit boards respectively disposed in a first dimension and a second dimension; and an acoustic-to-electric conversion element disposed between the two flexible circuit boards. A conductive layer and a matching layer are respectively provided on opposite sides of the acoustic-to-electric conversion element. The conductive layer is connected to one of the two flexible circuit boards in the first dimension, and the matching layer is connected to the other of the two flexible circuit boards in the second dimension. The acoustic-to-electric conversion element and the conductive layer are divided into N equal parts in the second dimension, and the acoustic-to-electric conversion element and the matching layer are divided into M equal parts in the first dimension, to form M x N array elements, where M and N are positive integers greater than 1.

[0006] Preferably, the two flexible circuit boards each have N first conductors and M second conductors, and the N first conductors and the M second conductors are respectively connected to the conductive layer and the matching layer.

[0007] Preferably, at least one of the N first conductors and the M second conductors includes two ground conductors and multiple signal conductors, with the two ground conductors located on opposite sides of the multiple signal conductors.

[0008] Preferably, the two flexible circuit boards each have a first opening and a second opening, the first opening corresponding to expose a portion of the conductive layer, and the second opening corresponding to expose a portion of the mating layer, wherein the N first wires extend to at least one side of the first opening, and the M second wires extend to at least one side of the second opening.

[0009] Preferably, it also includes an adhesive backing layer that covers the conductive layer in the first opening or the matching layer in the second opening.

[0010] Preferably, the acoustic-electric conversion element is composed of a piezoelectric element and two conductive materials stacked together, with the piezoelectric element located between the two conductive materials.

[0011] Preferably, the acoustic-electric conversion element further includes an adhesive material that fills the gaps between the M x N array elements.

[0012] The present invention also provides a method for manufacturing a two-dimensional ultrasonic transducer, comprising: forming an acoustic-electric conversion element; respectively disposing a conductive layer and a matching layer on opposite sides of the acoustic-electric conversion element; disposing a first flexible circuit board in a first dimension, the first flexible circuit board being connected to the conductive layer in the first dimension; cutting the acoustic-electric conversion element and the conductive layer to divide the acoustic-electric conversion element and the conductive layer into N equal parts in a second dimension; disposing a second flexible circuit board in the second dimension, the second flexible circuit board being connected to the matching layer in the second dimension; and cutting the acoustic-electric conversion element and the matching layer to divide the acoustic-electric conversion element and the matching layer into M equal parts in the first dimension to form M x N array elements, wherein M and N are positive integers greater than 1.

[0013] Preferably, the first flexible circuit board and the second flexible circuit board each have N first wires and M second wires, and the N first wires and the M second wires are respectively connected to the conductive layer and the matching layer.

[0014] Preferably, at least one of the N first conductors and the M second conductors includes two ground conductors and multiple signal conductors, with the two ground conductors located on opposite sides of the multiple signal conductors.

[0015] Preferably, the first flexible circuit board and the second flexible circuit board have a first opening and a second opening respectively, the first opening corresponding to expose a portion of the conductive layer, the second opening corresponding to expose a portion of the matching layer, wherein the N first wires extend to at least one side of the first opening, and the M second wires extend to at least one side of the second opening.

[0016] Preferably, the acoustic-electric conversion element is composed of a piezoelectric material element and two conductive materials stacked together, with the piezoelectric material element located between the two conductive materials.

[0017] Compared with the prior art, the two-dimensional ultrasonic transducer and its manufacturing method provided by the present invention, instead of the traditional method of electrically connecting the sound wave generating unit to the circuit board with multiple solder wires, uses a first flexible circuit board and a second flexible circuit board arranged in a two-dimensional direction to connect to the acoustic-electric conversion element. The assembly of the acoustic-electric conversion element and its sensing circuit is completed through steps such as flexible board bonding, cutting and glue filling. This produces a two-dimensional ultrasonic transducer with small size (suitable for handheld and mobile medical instruments) and many channels (e.g., more than 128 or 256 channels), thereby improving the overall requirements of two-dimensional ultrasonic transducers. Attached Figure Description

[0018] Figure 1A and Figure 1B The images show an exploded view and an assembled view of a two-dimensional ultrasonic transducer according to an embodiment of the present invention.

[0019] Figure 1C and Figure 1D These are exploded schematic diagrams of two-dimensional ultrasonic transducers according to two other embodiments of the present invention;

[0020] Figure 2A and Figure 2B These are schematic cross-sectional views of a two-dimensional ultrasonic transducer in the second dimension (YY dimension) and the first dimension (XX dimension), respectively.

[0021] Figures 3A to 3C The flowcharts show the fabrication methods of the acoustic-electric conversion elements of a two-dimensional ultrasonic transducer.

[0022] Figures 4A to 4C The flowcharts are respectively for setting the first flexible circuit board on the first dimension of the acoustic-electric conversion element;

[0023] Figures 5A to 5C The flowcharts are respectively for setting the second flexible circuit board on the second dimension of the acoustic-electric conversion element;

[0024] Figures 6A to 6B These are schematic diagrams showing the application of an adhesive backing layer to cover the conductive layer in the first opening.

[0025] Figure 7 This is a step diagram illustrating the manufacturing method of a two-dimensional ultrasonic transducer 100. Detailed Implementation

[0026] To provide a further understanding of the purpose, structure, features and functions of the present invention, detailed descriptions are provided below with reference to embodiments.

[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art under obvious circumstances are within the scope of protection of this application. The following description uses the same / similar symbols to denote the same / similar elements.

[0028] Please refer to Figure 1A , Figure 1B , Figure 2A and Figure 2B ,in Figure 1A and Figure 1B The images show an exploded view and an assembled view of a two-dimensional ultrasonic transducer 100 according to an embodiment of the present invention. Figure 2A and Figure 2B These are schematic cross-sectional views of the two-dimensional ultrasonic transducer 100 in the second dimension (YY dimension) and the first dimension (XX dimension), respectively.

[0029] According to an embodiment of the present invention, a two-dimensional ultrasonic transducer 100 includes two flexible circuit boards 112 and 114 and an acoustic-to-electric conversion element 116. The two flexible circuit boards 112 and 114 are respectively disposed in a first dimension and a second dimension. The acoustic-to-electric conversion element 116 is disposed between the two flexible circuit boards 112 and 114. A conductive layer 117 and a matching layer 118 are respectively provided on opposite sides of the acoustic-to-electric conversion element 116. The conductive layer 117 is connected to one of the flexible circuit boards in the first dimension, and the matching layer 118 is connected to the other flexible circuit board in the second dimension. The acoustic-to-electric conversion element 116 and the conductive layer 117 are divided into N equal parts in the second dimension, and the acoustic-to-electric conversion element 116 and the matching layer 118 are divided into M equal parts in the first dimension to form M x N array elements 101, where M and N are positive integers greater than 1.

[0030] Please refer to Figure 1A and Figure 2AThe acoustic-to-electric conversion element 116 is, for example, formed by stacking a piezoelectric element 1161 and two conductive materials 1162, with the piezoelectric element 1161 located between the two conductive materials 1162. The conductive materials 1162 are, for example, chromium / gold or titanium electrodes with a thickness of less than 1 micrometer or silver electrodes with a thickness of 1-100 micrometers. The piezoelectric element 1161 may be composed of one or more of the following: lead-zirconate-titanate (PZT), PZT ceramic, lead magnesiumniobate-lead titanate (PMN-PT), polyvinylidene fluoride (PVDF), poly(vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFE), and / or other PVDF copolymers. The piezoelectric element 1161 can generate voltage (piezoelectric effect) by applying external force (pressure) or deform by applying voltage (inverse piezoelectric effect). In this embodiment, by applying a voltage, the piezoelectric element 1161 is made to vibrate at a high frequency. This high-frequency vibration is a sound wave, and if the frequency of this sound wave falls within the ultrasonic range... This is ultrasonic vibration. Conversely, the ultrasonic signal can be received by utilizing the positive piezoelectric effect (mechanical energy to electrical energy conversion) of the piezoelectric element 1161, and then converted into a sensing signal.

[0031] Furthermore, the conductive layer 117 and matching layer 118 are, for example, conductive silver paste or other conductive materials. In order for the ultrasonic energy generated by the transducer 100 to be transmitted from the acoustic-to-electric conversion element 116 (e.g., piezoelectric ceramic) to an object or fluid (e.g., air or water), the acoustic impedance of the acoustic-to-electric conversion element 116 must be matched with the acoustic impedance of the object or fluid. For example, the conductive layer 117 and matching layer 118 can be made of a composite material of polymer resin and powder to reduce the acoustic impedance characteristics of the acoustic-to-electric conversion element 116, so that it matches the acoustic impedance of the object or fluid.

[0032] exist Figure 1A In this design, a first flexible circuit board 112 is disposed on the first dimension of the acoustic-to-electrical conversion element 116, and a second flexible circuit board 114 is disposed on the second dimension of the acoustic-to-electrical conversion element 116. The first dimension may be, for example, dimension XX, and the second dimension may be, for example, dimension YY; the two are interchangeable. To better understand the differences between the first and second dimensions of the acoustic-to-electrical conversion element 116, please refer to [reference needed]. Figure 2AThe acoustic-electric conversion element 116 and the conductive layer 117 are divided into N equal parts in the second dimension, with gaps between them (filled with cured adhesive 1151 or maintaining air gaps). The first flexible circuit board 112 is also divided into N equal parts (corresponding to N first wires 1121) when cutting the acoustic-electric conversion element 116 and the conductive layer 117. Therefore, the first wires 1121 of the first flexible circuit board 112 are electrically insulated from each other in the second dimension. Furthermore, the matching layer 118 is not completely severed when cutting the acoustic-electric conversion element 116 and the conductive layer 117 (only the top conductive matching layer 1181 is cut, while the bottom matching layer 1182 remains connected to each other), allowing the matching layer 118 to remain connected to the second wires 1141 of the second flexible circuit board 114 in the second dimension. This enables the acoustic-electric conversion element 116 to transmit and receive signals through the first flexible circuit board 112 and the second flexible circuit board 114 in both dimensions. The top conductive matching layer 1181 and the bottom matching layer 1182 described above may be composed of different matching materials or may not be configured at all. For example, the top conductive matching layer 1181 is usually a conductive adhesive or conductive silver paste, while the bottom matching layer 1182 is usually a polymer resin.

[0033] Next, please refer to Figure 2B The acoustic-electric conversion element 116 and the matching layer 118 are divided into M equal parts in the first dimension, with gaps between them (filled with cured adhesive 1152 or maintaining air gaps). The second flexible circuit board 114 is also divided into M equal parts when the acoustic-electric conversion element 116 and the matching layer 118 are cut (the conductors 1141 correspond to multiple signal conductors T and grounding conductors G on both sides). Therefore, the conductors 1141 of the second flexible circuit board 114 are electrically insulated from each other in the first dimension. Furthermore, the conductive layer 117 is not completely severed when the acoustic-electric conversion element 116 and the matching layer 118 are cut (only a portion of the matching layer is cut, while the remaining portion is retained and connected to each other), so that the conductive layer 117 remains connected to the first conductor 1121 of the first flexible circuit board 112 in the first dimension. This allows the acoustic-electric conversion element 116 to transmit and receive signals in both dimensions through the first flexible circuit board 112 and the second flexible circuit board 114, respectively.

[0034] Please refer to Figure 2A and Figure 2BThe first flexible circuit board 112 has, for example, N first conductive lines 1121, and the second flexible circuit board 114 has, for example, M second conductive lines 1141. These N first conductive lines 1121 and M second conductive lines 1141 are respectively connected to the conductive layer 117 and the matching layer 118 on opposite sides of the acoustic-electric conversion element 116. That is, the N first conductive lines 1121 are connected to the N equally divided conductive layer 117 in the second dimension, and the M second conductive lines 1141 are connected to the M equally divided matching layer 118 in the first dimension, thereby constituting an ultrasonic transducer 100 having an array of M x N two-dimensionally arranged elements 101.

[0035] In one embodiment, at least one of the M first conductors 1121 and the N second conductors 1141 includes a ground conductor G and a plurality of signal conductors T. For example, the ground conductor G may be located on any side or opposite sides of the signal conductors T (see [link to documentation]). Figure 1A Taking 20 first conductors 1121 and 28 second conductors 1141 as an example, apart from the grounding conductors G located on both sides of the first conductor 1121 and / or the grounding conductors G on both sides of the second conductor 1141, the remaining 16 first conductors 1121 and / or the remaining 24 second conductors 1141 can be signal conductors T, used to receive sensing signals from the acoustic-to-electric conversion element 116 or power signals input to the acoustic-to-electric conversion element 116. The grounding conductors G can reduce the influence of external electromagnetic fields on the aforementioned power signals or sensing signals, and are used to ground (lead to ground) external interference signals to prevent interference signals from entering the signal conductors T. Furthermore, when the M first conductors 1121 or the N second conductors 1141 are used to transmit or receive signals, the conductive material 1162 on the other side of the piezoelectric element 1161 can be used to directly or indirectly connect the two outermost grounding conductors G of the M first conductors 1121 or the N second conductors 1141 and provide grounding.

[0036] exist Figure 1A and Figure 1BIn the first flexible circuit board 112 and the second flexible circuit board 114, there are corresponding first openings 111 and second openings 113, respectively. The first opening 111 exposes a portion of the conductive layer 117, and the second opening 113 exposes a portion of the mating layer 118. The size of the first opening 111 in the X direction is slightly smaller than the size of the conductive layer 117. The peripheral region of the first opening 111 overlaps with the conductive layer 117, such that the first conductor 1121 located in the peripheral region of the first opening 111 is connected to the conductive layer 117, or for example, it can be connected to the conductive layer 117 through conductive adhesive. Furthermore, the size of the second opening 113 in the Y direction is slightly smaller than the size of the mating layer 118. The peripheral region of the second opening 113 overlaps with the mating layer 118, such that the second conductor 1141 located in the peripheral region of the second opening 113 is connected to the mating layer 118, or for example, it can be connected to the mating layer 118 through conductive adhesive. That is, N first conductors 1121 extend to at least one side of the first opening 111 (in... Figure 1A and Figure 1B (Extending from opposite sides toward the first opening 111) and respectively directly or indirectly connected to the N equally divided conductive layers 117, and M second wires 1141 extending to at least one side of the second opening 113 (in) Figure 1A and Figure 1B (Extending from the opposite sides to the second opening 113) and directly or indirectly connected to the matching layer 118, which is divided into M equal parts.

[0037] Please refer to Figure 1C In one embodiment, the size of the first opening 111 in the Y direction can be increased, making the size of the first opening 111 in the Y direction greater than the relative distance between the two grounding wires G. In addition, the size of the second opening 113 in the X direction can be increased, making the size of the second opening 113 in the X direction greater than the relative distance between the two grounding wires G.

[0038] Additionally, please refer to Figure 1D In one embodiment, when the size of the first opening 111 in the Y direction is small, providing sufficient flexible board space for the first flexible circuit board 112, the grounding wires G on both sides of the X-axis can extend to both sides of the first opening 111 and be connected as the same wire. Additionally, when the size of the second opening 113 in the X direction is small, providing sufficient flexible board space for the second flexible circuit board 114, the grounding wires G on both sides of the Y-axis can extend to both sides of the second opening 113 and be connected as the same wire.

[0039] In this embodiment, since the first opening 111 exposes the conductive layer 117 and no first wire 1121 passes through it, the aperture ratio of the conductive layer 117 is increased, thus the acoustic impedance matching of the conductive layer 117 can achieve better results. Furthermore, since the second opening 113 exposes the matching layer 118 and no second wire 1141 passes through it, the aperture ratio of the matching layer 118 is increased, thus the acoustic impedance matching of the matching layer 118 can achieve better results.

[0040] The manufacturing method of the two-dimensional ultrasonic transducer 100 is described in detail below. Please refer to [link / reference]. Figures 3A to 7 ,in Figures 3A to 3C The flowcharts show the fabrication methods of the acoustic-to-electric conversion element 116 of the two-dimensional ultrasonic transducer 100. Figures 4A to 4C The flowcharts show the setup of the first flexible circuit board 112 along the first dimension of the acoustic-electric conversion element 116. Figures 5A to 5C The flowcharts show the setup of the second flexible circuit board 114 on the second dimension of the acoustic-electric conversion element 116. Figures 6A to 6B These are schematic diagrams showing the application of an adhesive backing layer 120 to cover the conductive layer 117 in the first opening 111. Figure 7 This is a step diagram of the manufacturing method 200 for a two-dimensional ultrasonic transducer 100.

[0041] The manufacturing method 200 of the two-dimensional ultrasonic transducer 100 includes the following steps: First, step S10 is performed to form an acoustic-to-electric conversion element 116. Step S12 is performed to respectively deposit a conductive layer 117 and a matching layer 118 on opposite sides of the acoustic-to-electric conversion element 116. Step S14 is performed to deposit a first flexible circuit board 112 in a first dimension, the first flexible circuit board 112 being connected to the conductive layer 117 in the first dimension. Step S16 is performed to cut the acoustic-to-electric conversion element 116 and the conductive layer 117, dividing the acoustic-to-electric conversion element 116 and the conductive layer 117 into N equal parts in a second dimension. Step S18 is performed to deposit a second flexible circuit board 114 in a second dimension, the second flexible circuit board 114 being connected to the matching layer 118 in the second dimension. In step S20, the acoustic-electric conversion element 116 and the matching layer 118 are cut so that the acoustic-electric conversion element 116 and the matching layer 118 are divided into M equal parts in the first dimension to form M x N array elements. The above execution steps are only an explanation of each action of the manufacturing method of the two-dimensional ultrasonic transducer 100, and the execution order of each action is not limited to this.

[0042] exist Figures 3A to 3BIn this structure, the conductive layer 117 and the matching layer 118 are fixed to opposite sides of the acoustic-electric conversion element 116 by coating, deposition, or other methods. The thickness of the matching layer 118 can be greater than or equal to the thickness of the conductive layer 117. The thickness of the conductive layer 117 is greater than 20 micrometers, and the thickness of the matching layer 118 is also greater than 20 micrometers. The resonant frequency of the matching layer 118 can be designed according to 1 / 4 wavelength of ultrasound. From top to bottom, the conductive layer 117, the first conductive material 1162, the piezoelectric element 1161, the second conductive material 1162, and the matching layer 118 are stacked to form the acoustic-electric conversion element 116.

[0043] exist Figures 4A to 4C In this process, the first flexible circuit board 112 is disposed on the first dimension and is connected to the conductive layer 117. Then, the first flexible circuit board 112, the acoustic-electric conversion element 116, and the conductive layer 117 are cut from top to bottom with a cutting tool or multiple parallel cutting tools simultaneously from top to bottom, but the matching layer 118 is not cut off (see...). Figure 2A and Figure 4B Therefore, the first flexible circuit board 112, the acoustic-electric conversion element 116, and the conductive layer 117 are divided into N equal parts in the second dimension. Simultaneously, N-1 slits 1191 (i.e., cutting paths) generated by the cutting tool are formed between the N equal parts of the acoustic-electric conversion element 116 and the N equal parts of the conductive layer 117, subsequently... Figure 4C In this process, adhesive material 1151 is filled into each gap 1191 (i.e., the cutting channel) and cured to strengthen the structure of the acoustic-electric conversion element 116 or maintain the air gap.

[0044] Subsequently, Figure 4C The semi-finished acoustic-electric conversion element 116 is flipped so that its bottom matching layer 118 faces upward, to facilitate the bonding and cutting of the second flexible circuit board 114, as detailed below. Figures 5A to 5C In this process, the second flexible circuit board 114 is disposed on the second dimension and is connected to the matching layer 118. Then, the second flexible circuit board 114, the acoustic-electric conversion element 116, and the matching layer 118 are cut from top to bottom with a cutting tool or multiple parallel cutting tools simultaneously from top to bottom, but the conductive layer 117 is not cut (see...). Figure 2B and Figure 5B Therefore, the second flexible circuit board 114, the acoustic-electric conversion element 116, and the matching layer 118 are divided into M equal parts in the first dimension. Simultaneously, M-1 slits 1192 (i.e., cutting paths) generated by the cutting tool are formed between the M equal parts of the acoustic-electric conversion element 116 and the M equal parts of the matching layer 118, subsequently... Figure 5C In this process, adhesive material 1152 is filled into each gap 1192 (i.e., the cutting groove) and cured or maintained to strengthen the structure of the acoustic-electric conversion element 116. The above... Figures 4A to 4CSteps and Figures 5A to 5C The order of the steps can be interchanged, and this invention does not limit this.

[0045] exist Figure 6A and Figure 6B After completing the steps of bonding, cutting, and filling the first and second flexible circuit boards 112 and 114 as described above, an adhesive backing layer 120 can be formed on the conductive layer 117 or the matching layer 118. The side covering the adhesive backing layer 120 is the side that emits sound waves in the reverse direction, while the side not covered by the adhesive backing layer 120 is the side that emits sound waves in the forward direction. In this embodiment, the example of the adhesive backing layer 120 covering the conductive layer 117 is used for illustration, but it is not limited to this. Figure 6A and Figure 6B As shown, the adhesive layer 120 covers the conductive layer 117 in the first opening 111. The adhesive layer 120 is used to absorb the sound waves emitted in the opposite direction, that is, to absorb the sound waves transmitted towards the location of the adhesive layer 120 and the conductive layer 117, and to quickly restore the acoustic-electric conversion element 116 to a static state to reduce reverberation and affect signal interpretation. Therefore, the adhesive layer 120 must have strong attenuation characteristics so that the sound waves transmitted within the adhesive layer 120 are completely absorbed by the adhesive layer 120, without affecting the sound field transmitted forward (i.e., the location of the matching layer 118) and reducing signal interpretation problems caused by reverberation.

[0046] The two-dimensional ultrasonic transducer and its manufacturing method according to the above embodiments of the present invention, compared with the traditional method of electrically connecting the sound wave generating unit to the circuit board with multiple bonding wires, is changed to connecting the first flexible circuit board and the second flexible circuit board arranged in two dimensions to the acoustic-electric conversion element. The acoustic-electric conversion element and its sensing circuit are assembled through steps such as flexible board bonding, cutting and glue filling, so as to produce a two-dimensional ultrasonic transducer with small size (suitable for handheld and mobile medical instruments) and many channels (e.g., more than 128 or 256 channels), thereby improving the overall requirements of two-dimensional ultrasonic transducers.

[0047] In summary, the two-dimensional ultrasonic transducer and its manufacturing method provided by this invention include two flexible circuit boards and an acoustic-to-electric conversion element. The two flexible circuit boards are respectively disposed in a first dimension and a second dimension. The acoustic-to-electric conversion element is disposed between the two flexible circuit boards. A conductive layer and a matching layer are respectively provided on opposite sides of the acoustic-to-electric conversion element. The conductive layer is connected to one of the two flexible circuit boards in the first dimension, and the matching layer is connected to the other of the two flexible circuit boards in the second dimension. The acoustic-to-electric conversion element and the conductive layer are divided into N equal parts in the second dimension, and the acoustic-to-electric conversion element and the matching layer are divided into M equal parts in the first dimension to form M x N array elements, where M and N are positive integers greater than 1. In this way, a two-dimensional ultrasonic transducer can be manufactured with a small volume and a large number of channels, thereby improving the overall requirements of the two-dimensional ultrasonic transducer.

[0048] Although the invention has been described in conjunction with the accompanying drawings, the embodiments disclosed in the drawings are intended to illustrate preferred embodiments of the invention and should not be construed as limiting the invention. The scale in the schematic drawings does not represent the actual proportions of the components, in order to clearly describe the required parts.

[0049] The present invention has been described by the above-described embodiments; however, these embodiments are merely examples for implementing the present invention. It must be noted that the disclosed embodiments do not limit the scope of the present invention. Conversely, any modifications and refinements made without departing from the spirit and scope of the present invention are within the scope of patent protection of the present invention.

Claims

1. A two-dimensional ultrasonic transducer, characterized in that, include: Two flexible circuit boards are respectively set on the first dimension and the second dimension; as well as An acoustic-to-electric conversion element is disposed between the two flexible circuit boards. A conductive layer and a matching layer are respectively provided on opposite sides of the acoustic-to-electric conversion element. The conductive layer is connected to one of the two flexible circuit boards in the first dimension, and the matching layer is connected to the other of the two flexible circuit boards in the second dimension. The acoustic-to-electric conversion element and the conductive layer are divided into N equal parts in the second dimension, and the acoustic-to-electric conversion element and the matching layer are divided into M equal parts in the first dimension to form M×N array elements, where M and N are positive integers greater than 1. The two flexible circuit boards each have N first conductors and M second conductors, which are respectively connected to the conductive layer and the mating layer. The two flexible circuit boards each have a first opening and a second opening, with the first opening exposing a portion of the conductive layer and the second opening exposing a portion of the mating layer. The N first conductors extend to at least one side of the first opening, and the M second conductors extend to at least one side of the second opening.

2. The two-dimensional ultrasonic transducer as described in claim 1, characterized in that, At least one of the N first conductors and the M second conductors includes two ground conductors and multiple signal conductors, with the two ground conductors located on opposite sides of the multiple signal conductors.

3. The two-dimensional ultrasonic transducer as described in claim 1, characterized in that, It also includes an adhesive backing layer that covers the conductive layer in the first opening or the matching layer in the second opening.

4. The two-dimensional ultrasonic transducer as described in claim 1, characterized in that, The acoustic-electric conversion element is composed of a piezoelectric element and two conductive materials stacked together, with the piezoelectric element located between the two conductive materials.

5. The two-dimensional ultrasonic transducer as described in claim 1, characterized in that, The acoustic-electric conversion element also includes an adhesive material that fills the gaps between the M x N array elements.

6. A method for manufacturing a two-dimensional ultrasonic transducer, characterized in that, include: Forming a sound-to-electric conversion element; Conductive layers and matching layers are respectively disposed on opposite sides of the acoustic-electric conversion element; A first flexible circuit board is disposed in a first dimension, and the first flexible circuit board is connected to the conductive layer in the first dimension; The acoustic-electric conversion element and the conductive layer are cut so that the acoustic-electric conversion element and the conductive layer are divided into N equal parts in the second dimension; A second flexible circuit board is disposed on the second dimension, and the second flexible circuit board is connected to the mating layer on the second dimension; and The acoustic-electric conversion element and the matching layer are cut so that they are divided into M equal parts in the first dimension to form M×N array elements, where M and N are positive integers greater than 1; wherein the first flexible circuit board and the second flexible circuit board have N first wires and M second wires respectively, the N first wires and the M second wires are respectively connected to the conductive layer and the matching layer; the first flexible circuit board and the second flexible circuit board have opposite first openings and second openings, the first openings corresponding to expose a portion of the conductive layer, the second openings corresponding to expose a portion of the matching layer, wherein the N first wires extend to at least one side of the first opening, and the M second wires extend to at least one side of the second opening.

7. The method for manufacturing a two-dimensional ultrasonic transducer as described in claim 6, characterized in that, At least one of the N first conductors and the M second conductors includes two ground conductors and multiple signal conductors, with the two ground conductors located on opposite sides of the multiple signal conductors.

8. The method for manufacturing a two-dimensional ultrasonic transducer as described in claim 6, characterized in that, The acoustic-electric conversion element is composed of a piezoelectric material element and two conductive materials stacked together, with the piezoelectric material element located between the two conductive materials.

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