JP5377742B2 - Ultrasonic probe and ultrasonic transducer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic transducer and an ultrasonic probe capable of securing accuracy of a shape and a radiation direction of an ultrasonic beam radiated from the ultrasonic probe by securing positional accuracy of alignment of piezoelectric elements in the ultrasonic transducer. <P>SOLUTION: When a first piezoelectric body and a second piezoelectric body are arranged on a first printed board in an ultrasonic transducer and an ultrasonic probe, a first electrode lead and a second electrode lead of the first printed board are contained in a first concave groove or a second concave groove. Thereby, a gap generated between a surface of the first printed board and side surfaces of the first piezoelectric body and the second piezoelectric body is decreased. <P>COPYRIGHT: (C)2013,JPO&amp;INPIT

Description

  Embodiments described herein relate generally to an ultrasonic transducer incorporated in an ultrasonic probe used in an ultrasonic diagnostic apparatus.

  In order to acquire information on a desired diagnostic region of a subject using an ultrasonic probe, an ultrasonic diagnostic apparatus transmits (transmits) ultrasonic waves to the region, and reflects waves from tissue boundaries in the subject having different acoustic impedances. Receive. In this way, diagnosis is performed by scanning ultrasonic waves with an ultrasonic probe, obtaining information on the body tissue of the subject, and imaging it. This ultrasonic probe has an ultrasonic transducer in order to transmit an ultrasonic wave to a subject or the like and receive a reflected wave.

  In recent years, a method of rotating and swinging a one-dimensional array of ultrasonic transducers in an ultrasonic probe, or an electronic scanning type ultrasonic using a two-dimensional array of ultrasonic transducers in which piezoelectric elements are arranged in a matrix form. Studies on systems that collect and display ultrasonic images in three dimensions using probes are advancing. A three-dimensional ultrasonic image is useful for diagnosing a part that is easily overlooked in a two-dimensional image, and a tomographic image suitable for diagnosis and measurement can be obtained, so that improvement in diagnostic accuracy can be expected.

  However, in the method using an electronic scanning type two-dimensional array ultrasonic transducer, the number of piezoelectric elements is increased (for example, 10 to 100 times) by arranging the piezoelectric elements in two dimensions. It will be accompanied. The piezoelectric element and the ultrasonic diagnostic apparatus main body are connected via a relay substrate that performs processing of electrical signals, transmission / reception of electrical signals to / from the piezoelectric elements, and the increase in the number of piezoelectric elements The number of electrode leads for electrical connection between the relay substrate and the piezoelectric element is greatly increased.

  This significant increase in the number of electrode leads leads to a complicated connection structure between the piezoelectric element (piezoelectric body) in the ultrasonic probe and the transmission / reception circuit and the ultrasonic diagnostic apparatus main body in the relay substrate. If the connection structure is complicated, it may be difficult to realize a two-dimensional array of ultrasonic transducers. Therefore, the connection between the piezoelectric elements arranged on the two-dimensional array and the subsequent circuit, for example, the connection structure between the electrode lead and the relay substrate and the connection structure between the piezoelectric element and the electrode lead are not complicated. A configuration that enables realization of an ultrasonic transducer in the array is required.

  As an example of the connection structure of each piezoelectric element and electrode lead for solving this problem, for example, a structure in which a substrate corresponding to the piezoelectric element array is stacked and the electrode lead is drawn out is adopted, and the piezoelectric element array is supported. A structure has been proposed in which the pitch width of the electrode leads is expanded by pattern wiring formed on each layer of the lead relay substrate, and is arranged and drawn out on the IC substrate connection side serving as a relay circuit (for example, Patent Document 1). According to this structure, a large number of electrode leads can be extracted from the signal electrodes of the ultrasonic transducers arranged in a two-dimensional array in the ultrasonic probe, and the acoustic characteristics of the piezoelectric element can be maintained, and the IC can be mounted. Etc. can be easily realized.

  However, since the ultrasonic probe described in Patent Document 1 expands the pitch of the electrode leads drawn from the signal electrodes by the pattern wiring of the relay board connected to the ultrasonic transducer, the connection between the relay board and the ultrasonic transducer There is a possibility that the portion will be enlarged.

  Therefore, the inventors have prevented an increase in the size of the connection structure with the relay substrate, can draw a large number of electrode leads like the ultrasonic transducer described above, maintain the acoustic characteristics of the piezoelectric element, and mount an IC or the like. An ultrasonic transducer that can be easily realized is devised. An example of the structure of this ultrasonic transducer is shown in FIG. FIG. 8 is a schematic exploded perspective view showing an ultrasonic transducer unit 300a constituting an ultrasonic transducer of a two-dimensional array. In FIG. 8, the entire ultrasonic transducer is not shown and only a part of the structure is shown. However, the other parts are almost the same as the structure shown in the figure, and the structure (ultrasonic transducer unit 300a) is shown. ) Are continuously laminated to form an ultrasonic transducer.

  As shown in FIG. 8, piezoelectric elements for one column of a two-dimensional array are arranged on the front and back surfaces of the printed circuit board 330 in the ultrasonic transducer unit 300a constituting the ultrasonic transducer. That is, an acoustic matching layer 310, a first laminated piezoelectric body (piezoelectric element) 314, and a backing material (loading material phase) 318 are laminated in this order on the surface of the printed board 330 (the left side surface in FIG. 8). An acoustic matching layer 320, a second laminated piezoelectric body (piezoelectric element) 324, and a backing material 328 (loading material phase) are laminated in this order on the back surface of the printed circuit board 330. Similar to a single laminated piezoelectric body or the like, it is arranged in parallel. Conductive electrode leads 331 are arranged in parallel on the front and back surfaces of the printed circuit board 330.

  Further, as shown in FIG. 8, a front electrode formed between the acoustic matching layer and each laminated piezoelectric material (314, 324) on both surfaces of the printed board 330 is exposed on each side surface of the laminated piezoelectric material. 312 and 322 are arranged. Back electrodes 316 and 326 formed so as to be exposed on the respective side surfaces are disposed on the opposite side of the front electrodes 312 and 322, that is, between the backing material and the laminated piezoelectric material. Further, first internal electrodes 312a and 322a and second internal electrodes 316a and 326a are formed between the stacked piezoelectric elements.

  The front electrodes 312 and 322 and the first internal electrodes 312a and 322a are both configured to be the same type (positive electrode or negative electrode). Similarly, the back electrodes 316 and 326 and the second internal electrodes 316a and 326a are both configured to be the same type of electrode and different from the front electrode and the first internal electrode. With this configuration, one piezoelectric element is sandwiched between electrodes of different polarities, and the piezoelectric element can be driven with an electric signal.

  Further, as shown in FIG. 8, a printed metal substrate 330 and laminated piezoelectric materials (314 and 324) disposed on both surfaces of the printed circuit board 330 are variously formed by sputtering, vapor deposition, etc. by a conductive metal thin film 370. It is adhered by the method of. That is, by using this metal thin film 370, the electrical connection between each electrode such as the front electrodes 312 and 322 and each electrode lead (wiring pattern) on the printed circuit board 330 side is strengthened, and each laminated piezoelectric material and printed circuit board are strengthened. Glue with.

  As shown in FIG. 8, the metal thin film 370 is formed from the back electrodes 316 and 326 to the front electrodes 312 and 322 on the side surfaces of the laminated piezoelectric bodies 314 and 324. Therefore, when the metal thin film 370 is formed, the side surface of the first laminated piezoelectric body 314 is in contact with only the front electrode 312 and the first internal electrode 312a or the back electrode 316 and the second internal electrode 316a. It is configured. Similarly, the side surface of the second laminated piezoelectric body 324 is configured such that the metal thin film 370 contacts only either the front electrode 322 and the first internal electrode 322a or the back electrode 326 and the second internal electrode 326a. . By doing in this way, it can be set as the structure which pinches | interposes one piezoelectric element in a laminated piezoelectric material by the electrode of a different polarity.

  The structure of the side surface of the first laminated piezoelectric body 314 and the side surface of the second laminated piezoelectric body 324 will be described with reference to FIG. FIG. 9A is a schematic perspective view showing the transducer block before the grooves are formed in the process of forming the ultrasonic transducer. FIG. 9B is a partial enlarged view showing a side surface of the transducer block after the grooves are formed and the resin is filled in the process of forming the ultrasonic transducer. FIG. 9C is a schematic perspective view showing a process of forming a metal thin film on the side surface of the vibrator block after filling with the insulating resin shown in FIG. FIG. 9D is a schematic perspective view showing a state after the metal thin film is formed on the vibrator block.

  In the ultrasonic transducer, an ultrasonic transducer unit 300a (FIG. 8) is formed as follows. That is, first, one piezoelectric element is sandwiched between electrodes of different polarities from both sides thereof, in the ultrasonic transducer before division shown in FIG. 9A, the side surface of the first laminated piezoelectric body 314 (FIG. As shown in FIG. 9B, the portion of the electrode that is not brought into contact with the metal thin film 370 exposed on the right side surface of FIG. .

  That is, first, on the side surface (the right surface in the drawing) of the first laminated piezoelectric body 314, a groove perpendicular to the lamination direction of the piezoelectric elements is formed at the edge where the front electrode 312 is formed. Further, a groove perpendicular to the stacking direction of the piezoelectric elements is formed at the boundary portion of the piezoelectric element where the first internal electrode 312a is provided on the side surface. Insulating resins 311 and 315 are filled in these grooves. Further, on the side surface opposite to the side surface on which the insulating resins 311 and 315 are formed, at the edge where the back electrode 316 is formed and the boundary portion of the piezoelectric element where the second internal electrode 316a is provided, A groove perpendicular to the stacking direction of the piezoelectric elements is formed, and the groove is filled with insulating resin 317/313. By filling the grooves formed in this way with the insulating resins 311, 315, 313, and 317, it is possible to prevent the electrodes and metal thin films provided in the portions where the grooves are formed from being electrically coupled. it can.

  Furthermore, the side surface of the piezoelectric element after the insulation treatment shown in FIG. 9B is formed by, for example, curing the insulating resin (311 or the like) on the groove, grinding the insulating resin 311 or the like overflowing from the groove, It is formed by performing surface polishing of the side surface of the laminated piezoelectric body 314 to flatten the surface of the insulating resin.

  When the surface polishing step for the side surface of the first laminated piezoelectric body 314 is completed, a metal thin film 370 is formed on the side surface as shown in FIG. 9C, and a vibrator block as shown in FIG. 9D is formed. . Thereafter, this transducer block is divided to form one column of the two-dimensional array of ultrasonic transducers. Further, a second laminated piezoelectric body 324 having substantially the same structure as that of the first laminated piezoelectric body 314 as shown in FIG. 8 is formed on the back surface of the printed circuit board 330 in substantially the same process as the first laminated piezoelectric body 314. After that, as shown in FIG. 8, the surface of the printed circuit board 330 and the first laminated piezoelectric body 314 are bonded, thereby forming the ultrasonic transducer unit 300a.

  By configuring the side surface of the multilayer piezoelectric body as described above, the metal thin film 370 contacts only the same type of electrode (positive electrode or negative electrode) exposed on the side surface of the multilayer piezoelectric body. Therefore, only the same type of electrode can be connected to the electrode lead 331 of the printed circuit board 330 in contact with the metal thin film 370.

  In the ultrasonic transducer described above, the electrode leads 331 are provided not only on the front surface but also on the back surface of the printed circuit board 330, and in comparison with the configuration in which the piezoelectric elements are arranged only on one surface of one printed circuit board, It is possible to connect the subsequent stage electronic circuit to the two rows of piezoelectric elements with a single substrate, simplify the connection structure between the ultrasonic transducer and the subsequent stage electronic circuit, and reduce the size of the connecting portion. it can.

Japanese Patent Laid-Open No. 2001-292696

  Further, as described above, in the manufacturing process of the ultrasonic probe shown in FIGS. 8 and 9, the groove formed on the side surface of the laminated piezoelectric body is filled with the insulating resin 311 and the filled insulating resin 311 is cured. After that, it is necessary to grind the overflowing resin and to polish the side surface. However, since the vibrator block is very thin (for example, about 0.2 mm), the grinding operation and the surface polishing operation are very complicated.

  Furthermore, since the vibrator block is thin, there is a possibility that the thickness of the vibrator block may vary due to the grinding operation and the polishing operation. Furthermore, the surface may not be flat. The ultrasonic transducer as shown in FIG. 8 is formed by stacking the ultrasonic transducer units 300a. Therefore, when the transducer blocks are stacked due to variations in the thickness of the transducer blocks or surface irregularities. The positional accuracy of the piezoelectric bodies arranged in a two-dimensional manner is deteriorated. If the laminated piezoelectric body in the ultrasonic transducer of the ultrasonic probe is displaced from the original position, there is a possibility that the ultrasonic beam emitted from the ultrasonic transducer is adversely affected.

  That is, when each laminated piezoelectric body of the ultrasonic transducer is driven, the ultrasonic waves radiated from the laminated piezoelectric bodies whose positions are shifted are changed in the shape of the ultrasonic beam radiated from the entire ultrasonic transducer and the radiation direction. There is a risk of causing a shift. As a result, there is a possibility that the ultrasonic image generated by the ultrasonic diagnostic apparatus may be hindered. The conventional ultrasonic transducer has such a first problem.

  In the ultrasonic transducer as described above, an electrode lead is interposed between the piezoelectric body and the printed board. Further, when forming such a two-dimensional array of ultrasonic transducers, a plurality of ultrasonic transducers for one row arranged in parallel are stacked after piezoelectric elements are arranged in parallel on a printed circuit board. A process of forming a two-dimensional array of acoustic transducers is performed.

  However, when the planar piezoelectric side surface is arranged on the flat printed board, the electrode lead is interposed, and therefore the piezoelectric side surface and the printed board surface do not adhere to each other by the thickness of the electrode lead. That is, when the piezoelectric bodies are arranged in parallel on the printed circuit board or when a plurality of ultrasonic transducers for one row are stacked, the position of the piezoelectric body may be shifted with respect to the printed circuit board. Further, the piezoelectric body may be displaced with respect to the electrode lead.

  When the positional deviation occurs, the ultrasonic wave radiated from each of the displaced piezoelectric bodies is driven by the shape of the ultrasonic beam radiated from the entire ultrasonic transducer when each piezoelectric body of the ultrasonic transducer is driven. In addition, there is a risk of causing a shift in the radiation direction of the ultrasonic waves. As a result, there is a possibility that the ultrasonic image generated by the ultrasonic diagnostic apparatus may be hindered. Thus, the ultrasonic transducer as shown in FIG. 8 has the second problem as described above.

  The present invention has been made in view of the above problems, and its object is to secure the positional accuracy of the piezoelectric element array in the ultrasonic transducer, thereby to shape the ultrasonic beam emitted from the ultrasonic probe. It is another object of the present invention to provide an ultrasonic transducer and an ultrasonic probe that can ensure accuracy in the radiation direction.

  An ultrasonic transducer according to an embodiment includes a first printed circuit board, a plurality of first piezoelectric bodies, a plurality of second piezoelectric bodies, a plurality of first electrode leads, and a plurality of second electrode leads. . A front electrode is formed on the front surface of the first piezoelectric body on the ultrasonic radiation direction side. A back electrode is formed on the back surface of the first piezoelectric body opposite to the front surface. Further, the first piezoelectric body has a first concave groove. The first groove is formed from an edge on the front electrode side to an edge on the back electrode side on the first side surface orthogonal to the front surface and the back surface of the first piezoelectric body. In addition, a second concave groove is provided on the second side surface that is opposite to the first side surface of the first piezoelectric body. The second concave groove is formed on the second side surface from the edge on the front electrode side toward the edge on the back electrode side. The first piezoelectric body is arranged in parallel so that the front surface and the back surface are orthogonal to the surface of the first printed circuit board and the first side surface or the second side surface faces the surface. The second piezoelectric body has the same structure as the first piezoelectric body. Further, the front surface and the back surface of the second piezoelectric body are orthogonal to the back surface that is opposite to the front surface of the first printed circuit board. Further, the second piezoelectric body is arranged in parallel so that the first groove or the second groove faces the back surface of the first printed board. The first electrode lead is formed on the surface of the first printed circuit board. The first electrode lead is housed in the first concave groove or the second concave groove of the first piezoelectric body. The first electrode lead is directly or indirectly coupled to one of the front electrode and the back electrode of each of the first piezoelectric bodies. The second electrode lead is formed on the back surface of the first printed board. The second electrode lead is housed in the first groove or the second groove of the second piezoelectric body. The second electrode lead is coupled directly or indirectly to one of the front electrode or the back electrode of each of the second piezoelectric bodies.

  According to the first and seventh aspects of the invention, in the ultrasonic transducer in the ultrasonic probe, since the piezoelectric elements are arranged on the front and back surfaces of the printed circuit board, two rows of ultrasonic transducers in the two-dimensional array are arranged. Piezoelectric elements can be wired on a single printed circuit board. Therefore, it is possible to simplify the connection structure with the subsequent electronic circuit in the ultrasonic transducer in the ultrasonic probe. Furthermore, it is possible to facilitate the processing of electrical signals transmitted to and received from the ultrasonic transducer.

  Furthermore, according to the ultrasonic transducer of claim 1, when the first piezoelectric body and the second piezoelectric body are disposed with respect to the first printed board, the first electrode lead and the second electrode lead of the first printed board. Has an ultrasonic transducer housed in the first groove or the second groove. Therefore, the gap generated between the surface of the first printed circuit board and the side surfaces of the first piezoelectric body and the second piezoelectric body can be greatly reduced. As a result, the surface of the first printed circuit board and the side surfaces of the first piezoelectric body and the second piezoelectric body can be brought into close contact with each other, and the first piezoelectric body and the second piezoelectric body can be brought close to the first printed circuit board. It is possible to prevent a situation in which the position of the piezoelectric body is shifted.

  According to the ultrasonic probe of claim 7, when the first piezoelectric body and the second piezoelectric body are arranged with respect to the first printed board, the first electrode lead and the second electrode of the first printed board. The lead has an ultrasonic transducer that is housed in the first groove or the second groove. Therefore, the gap generated between the surface of the first printed circuit board and the side surfaces of the first piezoelectric body and the second piezoelectric body can be greatly reduced. As a result, the surface of the first printed circuit board and the side surfaces of the first piezoelectric body and the second piezoelectric body can be brought into close contact with each other, and the first piezoelectric body and the second piezoelectric body can be brought close to the first printed circuit board. It is possible to prevent a situation in which the position of the piezoelectric body is shifted.

(A) It is a schematic perspective view which shows the state which looked at the ultrasonic transducer concerning 1st Embodiment of this invention from the side. (B) It is a schematic exploded perspective view which shows the structure of the ultrasonic transducer unit which comprises the ultrasonic transducer concerning 1st Embodiment of this invention. (A) It is a schematic perspective view which shows the process in which a metal thin film is formed in a piezoelectric body block in the manufacturing process of the ultrasonic transducer | vibrator concerning 1st Embodiment of this invention. (B) It is a schematic perspective view which shows the state by which the metal thin film was formed in the side surface of the piezoelectric material block of FIG. 2 (A). (C) It is a schematic perspective view which shows the state in which the groove | channel was formed in the side surface of the piezoelectric material block of FIG. 2 (B). FIG. 3D is a schematic partial enlarged view of FIG. (A) It is a schematic perspective view which shows the process in which the piezoelectric material block of FIG. 2 (B) is arrange | positioned on a printed circuit board. FIG. 3B is a schematic perspective view showing the ultrasonic transducer before being divided after the ultrasonic transducer units in FIG. It is an example of the connection method of an ultrasonic transducer, The mechanism which connects the ultrasonic transducer and IC board in this embodiment, and the mechanism which connects IC on IC board and the cable connected to an ultrasonic diagnostic apparatus main body It is a schematic perspective view shown. (A) It is a schematic perspective view which shows the state which looked at the ultrasonic transducer concerning 2nd Embodiment of this invention from the side. (B) It is a schematic exploded perspective view which shows the structure of the ultrasonic transducer unit which comprises the ultrasonic transducer concerning 2nd Embodiment of this invention. (A) In the manufacturing process of the ultrasonic transducer | vibrator concerning 2nd Embodiment of this invention, it is a schematic perspective view which shows the state before a ditch | groove and a metal thin film are formed in a piezoelectric material block. (B) It is a schematic perspective view which shows the process in which a ditch | groove is formed with respect to the piezoelectric material block of FIG. 6 (A), and a metal thin film is formed. (C) It is a schematic perspective view which shows the state by which the metal thin film was formed in the piezoelectric body block through the process of FIG. 6 (A) * (B). (D) It is a general | schematic fragmentary enlarged view of FIG.6 (C). (A) In a manufacturing process of an ultrasonic transducer concerning a 2nd embodiment of this invention, it is a schematic perspective view showing a process of arranging a piezoelectric material block in which a metal thin film was formed on the front and back of a printed circuit board. FIG. 8B is a schematic perspective view showing the ultrasonic transducer before being divided after the ultrasonic transducer units in FIG. It is a schematic exploded perspective view which shows the ultrasonic transducer unit which comprises the ultrasonic transducer of a two-dimensional array. (A) It is a schematic perspective view which shows the vibrator | oscillator block before a groove | channel is formed in the formation process of an ultrasonic transducer. (B) It is the elements on larger scale which show the vibrator block side surface after a groove | channel was formed in the formation process of an ultrasonic transducer and it was filled with resin. FIG. 10C is a schematic perspective view showing a process of forming a metal thin film on the side surface of the vibrator block after filling with the insulating resin shown in FIG. (D) It is a schematic perspective view which shows the state after a metal thin film was formed in the vibrator | oscillator block.

[First Embodiment]
Hereinafter, an ultrasonic transducer and an ultrasonic probe according to a first embodiment of the present invention will be described with reference to FIGS.

  FIG. 1A is a schematic perspective view showing a state in which the ultrasonic transducer 100 according to the first embodiment of the present invention is viewed from the side. FIG. 1B is a schematic exploded perspective view showing the configuration of the ultrasonic transducer unit 100a constituting the ultrasonic transducer according to the first embodiment of the present invention. 1A and 1B show an example of an overall view and an example of an exploded view of an ultrasonic transducer manufactured by the manufacturing method according to the present invention. Hereinafter, the configuration of the ultrasonic transducer according to the first embodiment will be described.

(Schematic configuration of ultrasonic transducer)
As shown in FIG. 1A, an ultrasonic transducer 100 according to this embodiment includes a first laminated piezoelectric body 114 and a second laminated piezoelectric body 124 in which piezoelectric elements are laminated in three layers.
As shown in FIG. 1A, in the ultrasonic transducer 100, an acoustic matching layer 110 is provided adjacent to the stacking direction of the piezoelectric elements in the first stacked piezoelectric body 114. A backing material 118 (loading material phase) is provided on the opposite side of the first laminated piezoelectric body 114 from the acoustic matching layer 110 side. The acoustic matching layer 110, the first laminated piezoelectric body 114, and the backing material 118 constitute a piezoelectric block 101. Similarly, an acoustic matching layer 120 is provided adjacent to the stacking direction of the second laminated piezoelectric body 124, and a backing material 128 is provided on the opposite side of the acoustic matching layer 120. The acoustic block 120, the second laminated piezoelectric body 124, and the backing material 128 constitute the piezoelectric block 102. Further, electrode leads 131 formed of a wiring pattern are formed on the front and back surfaces of the printed circuit board 130.

  As shown in FIG. 1 (B), the piezoelectric block 101 has a plurality of electrode leads (not shown) formed in parallel on one surface of the printed circuit board 130 (the left surface in FIG. 1 (A) / hereinafter referred to as “front surface”). (Shown) are arranged in parallel. As shown in FIG. 1B, the piezoelectric block 102 has a plurality of electrode leads formed in parallel on the back surface (the right surface in FIG. 1A) opposite to the front surface of the printed circuit board 130. 131 are arranged in parallel on each other. The first laminated piezoelectric body 114 and the second laminated piezoelectric body 124 in these piezoelectric body blocks are arranged in the same direction with respect to the printed board 130. The electrode lead 131 corresponds to an example of a “wiring pattern” according to the present invention.

  Further, the first laminated piezoelectric body 114 and the printed board 130, and the second laminated piezoelectric body 124 and the printed board 130 are connected by a metal thin film 170. Thus, the ultrasonic transducer unit 100a which comprises the ultrasonic transducer 100 is formed by arrange | positioning and connecting the laminated piezoelectric material (114, 124) with respect to the front and back of the printed circuit board 130. FIG.

  Each of the ultrasonic transducer units 100a is further arranged on the front and back surfaces of the printed circuit board 130, and the direction from the first multilayer piezoelectric body 114 to the second multilayer piezoelectric body 124 (or from the second multilayer piezoelectric body 124 to the first multilayer piezoelectric body 114). In the direction toward). As described above, the directions of the ultrasonic transducer units 100a to be overlaid via the printed circuit board 130 are all the same direction. In this way, the laminated piezoelectric bodies are two-dimensionally arranged, and an ultrasonic transducer 100 as shown in FIG. 1A is configured. The printed circuit board 130 in the ultrasonic transducer unit 100a corresponds to an example of the “first printed circuit board” according to the present invention, and the printed circuit board 130 disposed between the ultrasonic transducer units 100a is the “first printed circuit board” according to the present invention. This corresponds to an example of “two printed circuit boards”.

(Structure of side surface and each electrode in laminated piezoelectric material)
As shown in FIG. 1B, in the first laminated piezoelectric body 114, a front electrode 112 is provided on the front surface adjacent to the acoustic matching layer 110. Further, a back electrode 116 is provided on the back surface opposite to the front surface. Furthermore, internal electrodes are provided between the piezoelectric elements stacked in the first stacked piezoelectric body 114. That is, among the piezoelectric elements stacked in three layers, a first internal electrode 112a driven corresponding to the front electrode 112 is provided between the back side piezoelectric element and the intermediate piezoelectric element. A second internal electrode 116a driven corresponding to the back electrode 116 is provided between the piezoelectric element and the intermediate piezoelectric element.

  The first laminated piezoelectric body 114 is orthogonal to the front surface and orthogonal to the back surface, and on the side surface on which the metal thin film 170 is provided, that is, on the first side surface facing the surface of the printed circuit board 130 (the right side surface in FIG. 1). The back electrode 116 and the second internal electrode 116a are configured to be exposed. The first laminated piezoelectric body 114 is configured such that the front electrode 112 and the first internal electrode 112a are exposed on a second side surface opposite to the first side surface.

  That is, on the first side surface of the first laminated piezoelectric body 114, the grooves 111 and 115 are formed so that the electrode lead 131 is not electrically coupled to the front electrode 112 and the first internal electrode 112a. The position of the groove 111 is on the boundary (on the front electrode 112) between the first multilayer piezoelectric body 114 and the acoustic matching layer 110 on the first side surface of the first multilayer piezoelectric body 114. That is, the groove 111 is formed along the edge (one side) of the piezoelectric element that is orthogonal to the stacking direction of the piezoelectric elements and is adjacent to the front electrode 112. The position of the groove 115 is on the boundary between the piezoelectric element on the back surface side of the first laminated piezoelectric body 114 and the intermediate piezoelectric element (on the first internal electrode 112a). The groove 115 is substantially parallel to the groove 111.

  Further, on the second side surface of the first laminated piezoelectric body 114, grooves 113 and 117 are formed so that the electrode lead of the printed circuit board 130 is not electrically coupled to the back electrode 116 and the second internal electrode 116a. The groove 117 is formed along the edge on the back electrode 116 side on the first side surface of the first multilayer piezoelectric body 114. The groove 113 is formed along the boundary between the intermediate piezoelectric element and the front piezoelectric element (on the second internal electrode 116a).

  As described above, the grooves on the first side surface and the second side surface of the first laminated piezoelectric body 114 are formed every other electrode in the order of the lamination direction of the piezoelectric elements.

  In contrast to the first laminated piezoelectric body 114, in the second laminated piezoelectric body 124, as shown in FIG. 1B, the first side surface (the right side surface in FIG. 1) and the second side surface (the left side in FIG. 1) The position where the groove is formed on the surface is reversed. That is, since the second side surface of the second multilayer piezoelectric body 124 faces the back surface of the printed circuit board 130 on which the first multilayer piezoelectric body 114 is disposed, the back electrode 116 and the second side surface are arranged on the second side surface. The second internal electrode 116a is exposed. Further, the front electrode 112 and the first internal electrode 112a are exposed on the first side surface on the opposite side.

  That is, the groove 121 is provided at the edge of the piezoelectric element adjacent to the front electrode 122 on the second side surface of the second laminated piezoelectric body 124. The groove 121 prevents the metal thin film 170 and the front electrode 122 from being electrically coupled. A groove 125 is provided at the boundary between the intermediate piezoelectric element on the second side surface of the second laminated piezoelectric body 124 and the piezoelectric element on the back side. The groove 125 insulates the metal thin film 170 and the first internal electrode 122a.

  Further, on the first side surface of the second laminated piezoelectric body 124, a groove 127 is formed at the edge on the back electrode 126 side, and a groove 123 is formed at the boundary between the intermediate piezoelectric element and the front piezoelectric element. The grooves 123 and 127 prevent the electrode lead 131 from being electrically coupled to the back electrode 126 and the second internal electrode 126a.

  As described above, the grooves on the first side surface and the second side surface of the second laminated piezoelectric body 124 are also arranged in the order of the lamination direction of the piezoelectric elements in the same manner as the grooves 111, 115, 113, and 117 in the first laminated piezoelectric body 114. Every other one is formed.

  Note that the gaps and grooves 111 and 121 of the metal thin film 170 formed by cutting the metal thin film 170 on the side surface of the laminated piezoelectric material correspond to an example of the “first groove” according to the present invention. The gaps and grooves 117 and 127 of the metal thin film 170 formed by cutting the metal thin film 170 on the side surface of the laminated piezoelectric material correspond to an example of the “second groove” according to the present invention. Similarly, the gap and groove 115 of the metal thin film 170 formed on the side surface of the multilayer piezoelectric material correspond to an example of the “third groove” according to the present invention, and the gap and groove 113 of the metal thin film 170 are the present invention. This corresponds to an example of the “fourth groove”.

As described above, in each of the first laminated piezoelectric body 114 and the second laminated piezoelectric body 124, a groove is formed on every other electrode together with the metal thin film 170 on the first side face and the second side face disposed on the electrode lead 131. Accordingly, one piezoelectric element in the laminated piezoelectric body can be sandwiched between electrodes of different polarities, and the ultrasonic transducer 100 is driven by applying an electrical signal to the electrodes on each side surface of the laminated piezoelectric body. Is possible.

  In addition, the ultrasonic transducer 100 of the present embodiment has electrode leads 131 provided not only on the front surface of the printed circuit board 130 but also on the back surface, and a structure in which piezoelectric bodies are arranged only on one surface of one printed circuit board. In comparison, it is possible to connect the second stage electronic circuit to the two rows of piezoelectric bodies with a single substrate. As a result, the connection structure between the printed board 130 and the relay board 201 that connects the ultrasonic transducer 100 and the IC board 200 (see FIG. 4) can be simplified. Further, the connection portion between the printed board 130 and the relay board 201 can be reduced in size.

(Manufacturing process)
Next, the manufacturing process of the ultrasonic transducer 100 according to the first embodiment will be described with reference to FIGS. FIG. 2A is a schematic perspective view showing a process of forming the metal thin film 170 on the piezoelectric block in the manufacturing process of the ultrasonic transducer 100 according to the first embodiment of the present invention. FIG. 2B is a schematic perspective view showing a state in which a metal thin film is formed on the side surface of the piezoelectric body block of FIG. FIG. 2C is a schematic perspective view showing a state in which a groove is formed on the side surface of the piezoelectric body block of FIG. FIG. 2D is a schematic partially enlarged view of FIG. FIG. 3A is a schematic perspective view showing a process in which the piezoelectric block of FIG. FIG. 3B is a schematic perspective view showing the ultrasonic transducer 100 before being divided after the ultrasonic transducer units 100a in FIG. 3A are stacked.

(Step 1)
First, piezoelectric elements are laminated in three layers, and internal electrodes are provided between the piezoelectric elements to form a laminated piezoelectric body before division. A front electrode is formed on the front surface of the laminated piezoelectric material, and a back electrode is formed on the back surface. Furthermore, by providing a sound electrode matching layer on the front surface and a backing material on the back surface of the laminated piezoelectric material, as shown in FIG. Piezoelectric blocks 101 and 102 are formed. The piezoelectric block has the same thickness as each of the laminated piezoelectric bodies of the ultrasonic transducer 100 when completed, and is two-dimensionally arranged in the ultrasonic transducer 100 when completed as shown in FIG. The laminated piezoelectric material has the same length as one row. This length direction is a direction orthogonal to the stacking direction of the piezoelectric elements. Further, as shown in FIG. 2B, the first side surface orthogonal to the front surface and the back surface of the multilayer piezoelectric body in this piezoelectric block and the second side surface opposite to the first side surface are made of metal. A thin film 170 is formed. Note that this piezoelectric block is divided from the acoustic matching layers 110 and 120 side in a subsequent process, and constitutes one row of laminated piezoelectric bodies in the ultrasonic transducer 100 of a two-dimensional array. Further, when the metal thin film 170 is formed on the first side surface and the second side surface, all the electrodes in which the metal thin film 170 is exposed on these side surfaces both on the first side surface and on the second side surface. Touching. Further, the step of forming the metal thin film 170 corresponds to an example of the “first step” in the present invention.

(Step 2)
After the metal thin film 170 is formed on the piezoelectric block as shown in FIG. 2B, as shown in FIGS. 2C and 2D, on the first side surface and the second side surface of the piezoelectric block. A groove is formed at a predetermined position. That is, each of the grooves (111, 115, 113, 117) is formed as follows. When the metal thin film 170 as shown in FIG. 2 (B) is formed on the side surface of the multilayer piezoelectric body, the first side surface of the first multilayer piezoelectric body 114 (the right side surface in FIG. 2 (B)) The front electrode 112 is exposed. The portion where the front electrode 112 is exposed, that is, the boundary between the acoustic matching layer 110 and the first laminated piezoelectric body 114 on the first side surface is cut together with the metal thin film 170 in a direction perpendicular to the lamination direction of the piezoelectric elements. . By cutting the portion, a groove 111 as shown in FIGS. 2C and 2D is formed. Further, on the first side surface of the first laminated piezoelectric body 114, a groove 115 parallel to the groove 111 is formed at a boundary portion between the back side piezoelectric element and the intermediate piezoelectric element. On the other hand, as shown in FIGS. 2C and 2D, the backing material 118 and the first laminated piezoelectric body 114 are formed on the second side surface of the first laminated piezoelectric body 114 (the left side surface in FIG. 2B). And the metal thin film 170 are cut in a direction perpendicular to the stacking direction of the piezoelectric elements. By cutting the portion, a groove 117 is formed on the second side surface of the first laminated piezoelectric body 114 as shown in FIGS. Further, on the second side surface of the first laminated piezoelectric body 114, a groove 113 parallel to the groove 117 is formed at the boundary portion between the front-side piezoelectric element and the intermediate piezoelectric element.

(Step 3)
In addition, after the metal thin film 170 is formed on the piezoelectric block relating to the second laminated piezoelectric body 124, a groove is also formed in the piezoelectric block. However, in the second laminated piezoelectric body 124, the position of the groove on the first side surface (the right side surface in FIG. 2B) and the second side surface is symmetrical to the first laminated piezoelectric material 114. That is, on the second side surface of the second laminated piezoelectric body 124, the boundary between the acoustic matching layer 120 where the front electrode 122 is exposed and the second laminated piezoelectric body 124 is perpendicular to the lamination direction of the piezoelectric elements. The metal thin film 170 is shaved. The groove 121 is formed by cutting the portion. Further, on the second side surface of the second laminated piezoelectric body 124, a groove 125 parallel to the groove 121 is formed at the boundary portion between the back side piezoelectric element and the intermediate piezoelectric element. Further, on the first side surface of the second laminated piezoelectric body 124 with respect to the second side surface, the boundary between the backing material 128 and the second laminated piezoelectric body 124 is set in a direction perpendicular to the lamination direction of the piezoelectric elements. Sharpen 170. The groove 127 is formed by cutting the portion. Further, on the first side surface of the second laminated piezoelectric body 124, a groove 123 parallel to the groove 127 is formed at the boundary portion between the front-side piezoelectric element and the intermediate piezoelectric element.

(Step 4)
After the grooves are formed on the first side surface and the second side surface of the first laminated piezoelectric body 114 and the second laminated piezoelectric body 124, respectively, the piezoelectric body block 101 and the piezoelectric body block 102 are shown in FIG. As shown in FIG. 2, the electrode leads 131 are respectively disposed on the printed circuit board 130. That is, the piezoelectric body block 101 is arranged on the front surface (the left surface in FIG. 3A) of the printed board 130 on which the electrode leads 131 are formed on the front and back surfaces. At this time, the position of the electrode lead 131 of the printed circuit board 130 and the position of the first side surface of the first laminated piezoelectric body 114 (the right side surface in FIG. 3A) are aligned. Further, a piezoelectric block 102 is disposed on the back surface of the printed board 130. Also in the piezoelectric block 102, the position of the electrode lead 131 on the back surface and the position of the second side surface (the left side surface in FIG. 3A) of the second laminated piezoelectric material 124 are aligned. Thus, the ultrasonic transducer unit 100a is formed by disposing the piezoelectric body blocks 101 and 102 on the front and back surfaces of the printed circuit board 130, respectively.

(Step 5)
After a plurality of ultrasonic transducer units 100a are formed, these are further stacked via the printed circuit board 130. That is, after the ultrasonic transducer unit 100a is formed as shown in FIG. 3A, the side surfaces of the piezoelectric blocks 101 and 102 formed on the front and back surfaces of the printed circuit board 130 that are not in contact with the printed circuit board 130 are formed. The printed circuit board 130 is arranged. For example, in the first laminated piezoelectric body 114 in the ultrasonic transducer unit 100a, the printed circuit board 130 is newly arranged on the second side surface opposite to the first side surface. In the second laminated piezoelectric body, a printed circuit board 130 is newly arranged on the first side surface opposite to the second side surface. Also at this time, the position of the second side surface of the first multilayered piezoelectric body 114, the position of the first side surface of the second multilayered piezoelectric body, and the position of the electrode lead 131 of each printed circuit board 130 are aligned. As described above, in the piezoelectric block of one ultrasonic transducer unit 100a, after the printed circuit board 130 is disposed on both vacant side surfaces, the other ultrasonic transducer unit 100a is stacked. At this time, the directions of the acoustic matching layers 110 and 120 of the adjacent ultrasonic transducer units 100a are the same. In this way, the ultrasonic transducer units 100a are stacked, and the ultrasonic transducer 100 before division is formed.

(Step 6)
After the ultrasonic transducer 100 is formed, as shown in FIG. From the acoustic matching layer 110/120 side, the ultrasonic transducer 100 is divided in a direction parallel to the stacking direction of the ultrasonic transducer unit 100a and perpendicular to the direction of the groove (111, etc.) on the side surface of the piezoelectric body. Grooves up to 128 are formed. The groove formed by the division is filled with an insulating resin to form an ultrasonic transducer 100 in which laminated piezoelectric bodies as shown in FIG. 1A are two-dimensionally arranged. The reason why the dividing groove is formed to reach the backing materials 118 and 128 is to reliably divide the laminated piezoelectric body in the piezoelectric block.

  In the ultrasonic transducer 100 according to the present embodiment, after the metal thin film 170 is provided on the side surface of the laminated piezoelectric material, a groove that insulates the electrode lead 131 of the printed circuit board 130 and the electrodes from each electrode portion together with the metal thin film 170. Form. Further, after forming the groove, the laminated piezoelectric body is disposed on the front and back surfaces of the printed board 130. Therefore, in the manufacturing process of the ultrasonic transducer 100, a process of partially polishing the side surface of the laminated piezoelectric body is not necessary in order to insulate the electrode lead 131 from each electrode. As a result, the complicated process of polishing the laminated piezoelectric material can be omitted. Furthermore, by omitting the polishing step, the flatness of the side surface of the laminated piezoelectric body can be ensured. As a result, when the ultrasonic transducer units 100a are stacked, the positional accuracy of each laminated piezoelectric body in the array of the laminated piezoelectric bodies of the ultrasonic transducer 100 can be ensured. By ensuring the positional accuracy of each laminated piezoelectric material in this way, it is possible to ensure the accuracy of the shape and radiation direction of the ultrasonic beam emitted from the ultrasonic probe.

  In the above, the manufacturing process of the ultrasonic transducer 100 according to the present embodiment has been described in the order of the above step 2 and step 3. However, the order of these processes may be reversed or performed simultaneously. Good. Further, in step 5, the ultrasonic transducer 100 is formed by laminating the ultrasonic transducer units 100a. However, the present invention is not limited to this embodiment, and the printed circuit board 130 and the piezoelectric blocks 101 and 102 are alternately laminated. It may be a process such as In the present embodiment, the steps 2 and 3 for forming the grooves 111, 121, 117, and 127 correspond to examples of the “first process” and the “second process” of the present invention.

  In the present embodiment, the steps 2 and 3 for forming the grooves 111, 121, 117, and 127 correspond to examples of the “first process” and the “second process” of the present invention. Further, in the step 4, the step of arranging the laminated piezoelectric body so that the position of the electrode lead 131 of the printed circuit board 130 and the position of the first side surface of the first laminated piezoelectric body 114 are aligned with each other in the “fourth aspect” of the present invention. It corresponds to an example of “process”. Further, the process of forming the ultrasonic transducer 100 by laminating the ultrasonic transducer units 100a corresponds to an example of “fifth process” and “sixth process” in the present invention.

(Connection between ultrasonic transducer and IC board)
Next, an example of a connection configuration between the ultrasonic transducer 100 and the IC substrate 200 according to the present embodiment will be described with reference to FIG. FIG. 4 shows an example of a method for connecting the ultrasonic transducer 100. The ultrasonic transducer 100 is connected to the mechanism for connecting the ultrasonic transducer 100 and the IC substrate 200, the IC 205 on the IC substrate 200, and the ultrasonic diagnostic apparatus main body. It is a schematic perspective view which shows the mechanism which connects the cable to be connected.

  As shown in FIG. 4, the ultrasonic transducer 100 and the IC substrate 200 are connected via a relay substrate 201. That is, the other end of each printed circuit board 130 opposite to one end on the ultrasonic wave irradiation direction side is connected to the relay substrate 201, whereby a plurality of electrode leads 131 arranged on both surfaces of the connected printed circuit board 130. Is connected to the IC 205 on the IC substrate 200 via the relay substrate 201.

  In the relay substrate 201, for example, a relay pad is disposed on the surface facing the ultrasonic transducer 100 according to the position of each electrode lead 131, and is connected to each electrode lead 131 of the ultrasonic transducer 100. At this time, an electrode pad may be provided on the end face of the printed circuit board 130 on the ultrasonic transducer 100 side, and the electrode pad and the relay pad may be connected. Further, as the relay substrate 201, it is desirable to use a flat substrate made of resin, ceramics or the like.

  As shown in FIG. 4, the IC board 200 is connected via a cable (both not shown) that is electrically connected to the ultrasonic diagnostic apparatus main body, and the IC board 200 and the cable are connected to the cable connection board 210. Connected by. One end of the cable connection board 210 is connected to one end of the IC board 200 opposite to the one provided with signal leads (not shown).

  The connectors 211 are provided at the other end of the cable connection board 210 and one end of the cable, respectively. The connector 211 connects the cable connection board 210 and the cable connected to the ultrasonic diagnostic apparatus main body. The ultrasonic transducer 100, the relay substrate 201, the IC substrate 200, the IC 205, the cable connection substrate 210, and the connector 211 in FIG. 4 constitute an ultrasonic probe 220.

  As shown in FIG. 4, an IC 205 is formed on an IC substrate 200 provided between the ultrasonic transducer 100 and the ultrasonic diagnostic apparatus main body, and the IC 205 is an electrode of a printed circuit board 130 via a relay substrate 201 or the like. The lead 131 is connected. This IC 205 applies a signal of the same kind to the front electrodes 112 and 122 and the first internal electrodes 112a and 122a, and an electric signal to be the same kind of electrodes to the back electrodes 116 and 126 and the second internal electrodes 116a and 126a. Is applied to drive the first laminated piezoelectric body 114 and the second laminated piezoelectric body 124. In this way, the IC 205 causes the ultrasonic transducer 100 to transmit an ultrasonic beam.

  The IC 205 processes signals received by the first laminated piezoelectric body 114 and the second laminated piezoelectric body 124. With such an arrangement, in the ultrasonic probe incorporating the ultrasonic transducer 100, the reflected waves received by the first laminated piezoelectric body 114 and the second laminated piezoelectric body 124 are converted into signals, and the signals are transferred to the IC substrate 200. The IC 205 processes the signal received by the IC 205. Further, the IC 205 transmits the processed signal to the ultrasonic diagnostic apparatus main body via the cable connection board 210. In this embodiment, the IC 205 is used, but includes an ASIC and other means.

(Action / Effect)
The operation and effect of the ultrasonic transducer 100 according to the first embodiment described above will be described.

  In the ultrasonic transducer 100 of the first embodiment, the metal thin film 170 is provided on each of the first side surface and the second side surface of the first laminated piezoelectric body 114 and the second laminated piezoelectric body 124. Further, by cutting each electrode portion together with the metal thin film 170 on the side surface, each groove such as the groove 111 is formed in a direction orthogonal to the stacking direction of the piezoelectric elements. Through these steps, a groove for insulating each electrode from the electrode lead 131 is formed. In addition, the laminated piezoelectric body is disposed on the electrode lead 131 after the groove 111 and the like are formed. On the side surface of the laminated piezoelectric body in such an ultrasonic transducer 100, the electrode (112 and the like) and the electrode lead 131 are non-contacted and insulated in the grooved portion, and the other portion is the electrode lead. Since it is in contact with the electrode 131, it is electrically connected to the electrode lead 131 particularly in the portion of the electrode (such as 112).

  Therefore, in the manufacturing process of the ultrasonic transducer 100, the electrode lead 131 of the printed circuit board 130, the front electrodes 112 and 122, the first internal electrodes 112a and 122a, the second internal electrodes 116a and 126a, or the back electrodes 116 and 126, In order to insulate, a process of providing an insulating resin on each electrode portion on the first side surface and the second side surface, curing the insulating resin, and then partially polishing and removing the cured resin. It is unnecessary. As a result, the process of polishing the side surface of the multilayer piezoelectric body from the manufacturing process of the ultrasonic transducer 100 can be omitted, and the complexity of the manufacturing process can be eliminated. In addition, since the surface polishing step is omitted, it is possible to eliminate the situation that the flatness of the side surface of the laminated piezoelectric body is hindered due to the polishing step, and it is possible to ensure the flatness.

  When the flatness of the side surface of the laminated piezoelectric material is ensured, it is possible to secure the arrangement of the two-dimensional array in the ultrasonic transducer 100 and the positional accuracy of each laminated piezoelectric material when the ultrasonic transducer units 100a are stacked. By ensuring the positional accuracy of each laminated piezoelectric material in this way, it is possible to ensure the accuracy of the shape and radiation direction of the ultrasonic beam emitted from the ultrasonic probe.

  In addition, the ultrasonic transducer 100 of the present embodiment described above is provided with electrode leads 131 not only on the front surface but also on the back surface of the printed circuit board 130, and the piezoelectric bodies are arranged only on one surface of one printed circuit board. Compared with the structure to perform, it can connect with a back | latter stage electronic circuit with one board | substrate with respect to two rows of piezoelectric bodies. As a result, the connection structure between the printed board 130 and the relay board 201 that connects the ultrasonic transducer 100 and the IC board 200 (see FIG. 4) can be simplified. Further, the connection portion between the printed board 130 and the relay board 201 can be reduced in size.

[Second Embodiment]
Next, an ultrasonic transducer according to a second embodiment of the present invention will be described with reference to FIGS. FIG. 5A is a schematic perspective view showing a state in which the ultrasonic transducer 100 according to the second embodiment of the present invention is viewed from the side. FIG. 5B is a schematic exploded perspective view showing the configuration of an ultrasonic transducer unit 100a constituting the ultrasonic transducer according to the second embodiment of the present invention.

  The outline of the second embodiment will be described below. Some ultrasonic transducers configured by disposing a piezoelectric body on a printed circuit board as shown in FIG. 8 have the electrode leads disposed on at least the surface of the printed circuit board. On the printed circuit board of such an ultrasonic transducer, substantially linear electrode leads are arranged in parallel. Further, the piezoelectric body of the ultrasonic transducer is disposed on the electrode lead.

  Therefore, in the ultrasonic transducer as described above, the electrode lead is interposed between the piezoelectric body and the printed board. Further, when forming such a two-dimensional array of ultrasonic transducers, a plurality of ultrasonic transducers for one row arranged in parallel are stacked after piezoelectric elements are arranged in parallel on a printed circuit board. A process of forming a two-dimensional array of acoustic transducers is performed.

  However, when the planar piezoelectric side surface is arranged on the flat printed board, the electrode lead is interposed, and therefore the piezoelectric side surface and the printed board surface do not adhere to each other by the thickness of the electrode lead. That is, when the piezoelectric bodies are arranged in parallel on the printed circuit board or when a plurality of ultrasonic transducers for one row are stacked, the position of the piezoelectric body may be shifted with respect to the printed circuit board. Further, the piezoelectric body may be displaced with respect to the electrode lead.

  When the positional deviation occurs, the ultrasonic wave radiated from each of the displaced piezoelectric bodies is driven by the shape of the ultrasonic beam radiated from the entire ultrasonic transducer when each piezoelectric body of the ultrasonic transducer is driven. In addition, there is a risk of causing a shift in the radiation direction of the ultrasonic waves. As a result, there is a possibility that the ultrasonic image generated by the ultrasonic diagnostic apparatus may be hindered. Thus, the ultrasonic transducer as shown in FIG. 8 has the above-described problems.

  The ultrasonic transducer according to the second embodiment has been made in view of the above problems. The outline is an ultrasonic transducer in which a groove having a size to accommodate an electrode lead is formed in the ultrasonic radiation direction on the side surface of the piezoelectric body that is orthogonal to the front surface and the back surface of the piezoelectric material and faces the printed circuit board. is there. In this ultrasonic transducer, when the piezoelectric body is disposed on the printed board, the electrode lead on the printed board is accommodated in the groove.

  In other words, the gap between the electrode leads generated between the surface of the printed circuit board and the side surface of the piezoelectric body is greatly reduced. As a result, it is possible to prevent a situation in which the position of the piezoelectric body is displaced with respect to the printed circuit board by bringing the surface of the printed circuit board and the side surface of the piezoelectric body into close contact or close to each other. Furthermore, since the electrode lead is accommodated in the groove, even if a force is applied in such a direction that the piezoelectric body is displaced with respect to the printed circuit board, the positional deviation can be avoided. In addition, as a result of preventing such displacement, the positional accuracy of the piezoelectric element arrangement in the ultrasonic transducer is ensured, and it is possible to ensure the accuracy of the shape and radiation direction of the ultrasonic beam emitted from the ultrasonic probe. Become.

  The configuration of the ultrasonic transducer according to the second embodiment will be described below.

  As shown in FIG. 5A, the ultrasonic transducer 100 according to the second embodiment includes laminated piezoelectric bodies 114 and 124 in which piezoelectric elements are laminated in three layers, as in the first embodiment, and The acoustic matching layers 110 and 120 are provided on the front surface in the stacking direction of the multilayer piezoelectric body, and the backing materials 118 and 128 are provided on the back surface opposite to the front surface. The acoustic matching layer 110, the first laminated piezoelectric body 114, and the backing material 118 constitute the piezoelectric body block 101. The acoustic matching layer 120, the second laminated piezoelectric body 124, and the backing material 128 constitute the piezoelectric body block 102. Further, front electrodes 112 and 122 are provided on the front surface of the laminated piezoelectric material, and back electrodes 116 and 126 are provided on the back surface. Further, internal electrodes 112a, 122a, 116a, and 126a are provided between the piezoelectric elements in the laminated piezoelectric material. Since the function of each part of these ultrasonic transducers and the positional relationship of each part are the same as those of the ultrasonic transducer according to the first embodiment, description thereof will be omitted.

  As shown in FIG. 5B, as in the first embodiment, a plurality of piezoelectric blocks 101 and 102 in the ultrasonic transducer 100 according to the second embodiment are formed in parallel on the front and back surfaces of the printed board 130. The electrode leads 131 are arranged in parallel. The arrangement direction of the first laminated piezoelectric body 114 and the second laminated piezoelectric body 124 with respect to the printed circuit board 130 is the same direction.

  Further, as shown in FIG. 5B, the first laminated piezoelectric body 114 and the printed board 130, and the second laminated piezoelectric body 124 and the printed board 130 are connected by a metal thin film 170. Thus, the ultrasonic transducer unit 100a constituting the ultrasonic transducer 100 is formed by arranging and connecting the laminated piezoelectric bodies to the front and back surfaces of the printed circuit board 130.

  Each of the ultrasonic transducer units 100a is further disposed on the front and back surfaces of the printed circuit board 130, and is laminated in a direction orthogonal to the lamination direction of the piezoelectric elements in the laminated piezoelectric body. As described above, the directions of the ultrasonic transducer units 100a stacked via the printed circuit board 130 are all the same. In this way, the laminated piezoelectric bodies are two-dimensionally arranged to constitute an ultrasonic transducer 100 as shown in FIG.

  Note that the ultrasonic transducer 100 according to the second embodiment is configured to have a laminated piezoelectric material, but in the ultrasonic transducer of the present invention, it is also possible to use a piezoelectric material having a single piezoelectric element. Further, in the ultrasonic transducer 100 according to the second embodiment, the electrode leads 131 are provided on the front and back surfaces of the printed circuit board 130. However, the electrode leads 131 may be provided on either one of the front and back surfaces. . Further, the first laminated piezoelectric body 114 and the second laminated piezoelectric body 124 may have the same structure.

(Structure of side face in laminated piezoelectric material)
Next, the configuration of the side surfaces of the laminated piezoelectric bodies 114 and 124 and the backing materials 118 and 128 according to the second embodiment will be described with reference to FIG. As shown in FIG. 5B, the first laminated piezoelectric body 114 of the ultrasonic transducer 100 according to the second embodiment is orthogonal to the front surface and the back surface, is opposed to the surface of the printed circuit board 130, and is on the electrode lead 131. A concave groove 119 having a concave shape is provided on the first side surface disposed on the first side surface. The concave groove 119 passes through the back electrode 116 from the front electrode 112 on the first side surface of the first multilayer piezoelectric body 114 in the piezoelectric block 101 to the subsequent electronic circuit side (relay substrate side) in the backing material 128. It reaches. The width of the concave groove 119 (the length in the direction orthogonal to the stacking direction of the first multilayer piezoelectric body) is substantially the same as the width of the electrode lead 131 or slightly longer than the width of the electrode lead 131. The By configuring the concave groove 119 in this manner, the electrode lead 131 is accommodated in the concave groove 119 when the first laminated piezoelectric body 114 is disposed on the printed circuit board 130.

  Further, the depth of the concave groove 119 (the length from the first side surface of the first laminated piezoelectric body 114 to the bottom surface of the concave groove 119) is formed slightly shallower than the height at which the electrode lead 131 protrudes from the printed circuit board 130. It is desirable. This is because when the first side surface of the first multilayer piezoelectric body 114 is disposed on the surface of the printed circuit board 130, a force to contact the printed circuit board 130 and the first multilayer piezoelectric body 114 is applied to the electrode lead 131 portion. This is to make it easier to concentrate on. By configuring the concave groove 119 in this manner, the electrical connection between the electrode lead 131 and each electrode (front electrode 112, etc.) in the laminated piezoelectric body is ensured.

  Further, it is desirable that the concave groove 119 has a shape corresponding to the shape of the electrode lead 131. That is, with this configuration, the position of the laminated piezoelectric material in the direction orthogonal to the lamination direction of the piezoelectric elements, which is likely to occur when the first side surface of the first laminated piezoelectric material 114 is arranged on the surface of the printed circuit board 130. A shift can be prevented.

  Further, similarly to the first side surface of the first laminated piezoelectric body 114, the concave groove 119 is provided also on the second side surface. Further, as shown in FIG. 5B, the first side surface and the second side surface of the second multilayer piezoelectric body 124 in the piezoelectric body block 102 are also backed in the same manner as the concave groove 119 of the first multilayer piezoelectric body 114. A concave groove 129 formed to reach the material 128 is formed. In the ultrasonic transducer according to the second embodiment, the insulation treatment between the metal thin film 170 and each electrode on the side surfaces of the first laminated piezoelectric body 114 and the second laminated piezoelectric body 124 is configured in the same manner as in the first embodiment. It is also possible. However, in this case, the depth of each concave groove 119 is formed shallower than the depth of the grooves 111, 113, 115, and 117. The depth of each concave groove 129 is shallower than the depth of the grooves 121, 123, 125, and 127. This is because when the groove is deeper, the metal thin film 170 comes into contact with each electrode of the laminated piezoelectric material to be insulated.

(Manufacturing process)
Next, the outline of the manufacturing process of the ultrasonic transducer 100 according to the present embodiment will be described with reference to FIGS. FIG. 6A is a schematic perspective view showing a state before the concave groove 119 and the metal thin film 170 are formed in the piezoelectric body block in the manufacturing process of the ultrasonic transducer 100 according to the second embodiment of the present invention. . FIG. 6B is a schematic perspective view showing a process in which the groove 119 is formed in the piezoelectric block of FIG. 6A and the metal thin film 170 is formed. FIG. 6C is a schematic perspective view showing a state in which the metal thin film 170 is formed on the piezoelectric block through the steps of FIGS. 6A and 6B. FIG. 6D is a schematic partially enlarged view of FIG. FIG. 7A is a schematic perspective view showing a process of arranging the piezoelectric block on which the metal thin film 170 is formed on the front and back surfaces of the printed circuit board 130 in the manufacturing process of the ultrasonic transducer 100 according to the second embodiment of the present invention. FIG. FIG. 7B is a schematic perspective view showing the ultrasonic transducer 100 before being divided after the ultrasonic transducer units 100a in FIG. 7A are stacked.

  In addition, since the process until formation of a piezoelectric body block is the same as the manufacturing process of the ultrasonic transducer | vibrator concerning 1st Embodiment, description is omitted.

(Step 1)
As shown in FIG. 6B, first, front electrodes are formed on the first and second side surfaces of the piezoelectric blocks 101 and 102 before the concave grooves as shown in FIG. 6A are formed. Concave grooves 119 and 129 are formed from the formed portion to the end of the backing material opposite to the boundary portion with the laminated piezoelectric body. The concave grooves are formed in substantially the same direction as the stacking direction of the piezoelectric elements in the stacked piezoelectric body.

(Step 2)
Next, as shown in FIG. 6B, a metal thin film 170 is formed on the first side face and the second side face of the laminated piezoelectric body in the piezoelectric body block in which the concave grooves are formed. This piezoelectric body block is divided in the subsequent steps, and constitutes one row of laminated piezoelectric bodies in the ultrasonic transducer 100 of a two-dimensional array.

(Step 3)
After the metal thin film 170 is formed on the first side surface and the second side surface of the first laminated piezoelectric body 114 and the second laminated piezoelectric body 124, respectively, the piezoelectric body block 101 and the piezoelectric body block 102 are shown in FIG. As shown in FIG. 3, the electrode lead 131 is disposed on the printed board 130. That is, the piezoelectric block 101 is disposed on the front surface (the left surface in FIG. 7A) of the printed circuit board 130 before being divided, on which the electrode leads 131 are formed on the front and back surfaces. At this time, the position of the electrode lead 131 of the printed circuit board 130 and the position of the first side surface (the right side surface in FIG. 7A) of the first laminated piezoelectric body 114 are arranged to match. Further, a piezoelectric block 102 is disposed on the back surface of the printed board 130. Also in the piezoelectric block 102, the position of the electrode lead 131 on the back surface and the position of the second side surface (the left side surface in FIG. 7A) of the second laminated piezoelectric material 124 are aligned. In this way, the piezoelectric block is formed on the front and back surfaces of the printed circuit board 130, and the ultrasonic transducer unit 100a before division is formed.

(Step 4)
When a plurality of ultrasonic transducer units 100a are formed, these are further stacked via the printed circuit board 130 as in the first embodiment. In this way, the ultrasonic transducer units 100a are stacked, and the ultrasonic transducer 100 before division is formed.

(Step 5)
After the ultrasonic transducer 100 is formed, as shown in FIG. From the acoustic matching layer 110/120 side, the ultrasonic transducer 100 is divided in a direction parallel to the stacking direction of the ultrasonic transducer unit 100a and perpendicular to the direction of the groove (111 etc.) on the side surface of the piezoelectric body. An ultrasonic transducer 100 shown in FIG. 1A is formed by filling the groove formed by the division with an insulating resin.

  Note that the connection between the ultrasonic transducer 100 and the IC substrate in the second embodiment is the same as that of the ultrasonic transducer according to the first embodiment, and a description thereof will be omitted.

(Action / Effect)
Operations and effects of the ultrasonic transducer 100 according to the second embodiment described above and an ultrasonic probe (not shown) using the ultrasonic transducer 100 will be described.

  The ultrasonic transducer 100 and the ultrasonic probe 220 using the ultrasonic transducer 100 according to the second embodiment are provided with a backing material (from the first side surface and the second side surface orthogonal to the front surface and the back surface of the laminated piezoelectric material (114, 124). 118, 128) and a concave groove (119, 129) formed continuously. The concave groove is formed in the same direction as the stacking direction of the piezoelectric elements from the edge on the front electrode side on the first side surface, and from the front electrode side edge to the rear electronic circuit side in the backing material via the back electrode It is formed so that it may extend | stretch to. Further, the concave groove is formed to have a width substantially the same as or slightly larger than the electrode lead 131 in the printed board 130.

  Therefore, when the laminated piezoelectric body is arranged on the printed board 130, the electrode lead 131 is accommodated in the concave groove. That is, the gap generated between the surface of the printed circuit board 130 and the side surface of the piezoelectric body can be greatly reduced. As a result, the surface of the printed circuit board 130 and the side surface of the multilayer piezoelectric body can be brought into close contact with each other, or a situation in which the position of the multilayer piezoelectric body is displaced from the printed circuit board 130 can be prevented.

  Further, since the electrode lead 131 is accommodated in the concave groove (119, 129), when the laminated piezoelectric material is disposed on the printed circuit board 130, a force is applied in such a direction that the laminated piezoelectric material is displaced with respect to the printed circuit board 130. However, it is possible to avoid the positional deviation. In addition, as a result of preventing such displacement, the positional accuracy of the piezoelectric element array in the ultrasonic transducer 100 is ensured, and the accuracy of the shape and radiation direction of the ultrasonic beam emitted from the ultrasonic probe can be ensured. It becomes.

  In addition, since the ultrasonic transducer 100 of the present embodiment described above can greatly reduce the gap generated between the surface of the printed circuit board 130 and the side surface of the piezoelectric body, the ultrasonic transducer unit 100a in the stacking direction. The laminated thickness can be reduced, and the ultrasonic transducer 100 and the ultrasonic probe can be miniaturized.

  In addition, the ultrasonic transducer 100 of the present embodiment described above is provided with electrode leads 131 not only on the front surface but also on the back surface of the printed circuit board 130, and the piezoelectric bodies are arranged only on one surface of one printed circuit board. Compared with the structure to perform, it can connect with a back | latter stage electronic circuit with one board | substrate with respect to two rows of piezoelectric bodies. As a result, the connection structure between the printed board 130 and the relay board 201 that connects the ultrasonic transducer 100 and the IC board 200 (see FIG. 4) can be simplified. Further, the connection portion between the printed board 130 and the relay board 201 can be reduced in size.

DESCRIPTION OF SYMBOLS 100 Ultrasonic transducer 100a Ultrasonic transducer unit 101 * 102 Piezoelectric block 110 * 120 Acoustic matching layer 111 * 113 * 115 * 117 * 121 * 123 * 125 * 127 Groove 112 * 122 Front electrode 112a * 122a 1st internal electrode 114 First laminated piezoelectric material 124 Second laminated piezoelectric material 116/126 Back electrode 116a / 126a Second internal electrode 118/128 Backing material 119/129 Groove 130 Printed circuit board 131 Electrode lead 200 IC board 201 Relay board 205 IC
210 Cable connection board 220 Ultrasonic probe

Claims (7)

A first printed circuit board;
A front electrode is formed on the front surface in the ultrasonic radiation direction side, a back electrode is formed on the back surface on the opposite side, and the back electrode is formed from an edge on the front electrode side on the front surface and a first side surface orthogonal to the back surface. A first concave groove formed toward the side edge, and from the edge on the front electrode side toward the edge on the back electrode side on the second side surface opposite to the first side surface. And are arranged in parallel so that the front surface and the back surface are orthogonal to the surface of the first printed circuit board and the first side surface or the second side surface faces the surface. A plurality of first piezoelectric bodies;
It has the same structure as the first piezoelectric body, and the front surface and the back surface thereof are orthogonal to the back surface opposite to the front surface of the first printed circuit board, and the first concave groove or the second concave groove is provided. A plurality of second piezoelectric bodies arranged in parallel so as to face the back surface;
Formed on the front surface of the first printed circuit board and housed in the first or second groove of the first piezoelectric body, and the front electrode or back surface of the first piezoelectric body, respectively. A plurality of first electrode leads coupled directly or indirectly to one of the electrodes;
Formed on the back surface of the first printed circuit board, housed in the first or second groove of the second piezoelectric body, and the front electrode or back surface of the second piezoelectric body, respectively. A plurality of second electrode leads coupled directly or indirectly to one of the electrodes;
Ultrasonic transducer characterized by. Each of the first piezoelectric body and the second piezoelectric body is configured by stacking a plurality of piezoelectric elements in the direction from the front surface to the back surface, and between each of the stacked piezoelectric elements. A laminated piezoelectric body on which internal electrodes are formed;
The ultrasonic transducer according to claim 1. The height at which the first electrode lead and the second electrode lead protrude from the surface of the first printed circuit board is longer than the depth of the first groove and the second groove,
The ultrasonic transducer according to claim 1. Each of the first electrode lead and the second electrode lead on the first printed circuit board includes only the same type of electrodes among the front electrode and the back electrode of the corresponding first piezoelectric body and second piezoelectric body. Are combined,
The ultrasonic transducer according to claim 1. Via a conductive thin film provided between the first electrode lead or the first side surface on the first piezoelectric body side facing the surface of the first printed circuit board and the first electrode lead The first electrode lead in the first printed circuit board and the front electrode or the back electrode in the first piezoelectric body are connected,
Via the first thin film on the second piezoelectric material side facing the back surface of the first printed circuit board or a conductive thin film provided between the second side wall and the second electrode lead The second electrode lead of the first printed circuit board is connected to the front electrode or the back electrode of the second piezoelectric body;
The ultrasonic transducer according to claim 1. The first printed circuit board has substantially the same structure and is opposite to the second side surface or the second side surface of the first piezoelectric body opposite to the first side surface connected to the first printed circuit board. A second printed circuit board whose surface is directly or indirectly connected to the first side surface,
It has the same structure as the first piezoelectric body, and the front surface and the back surface thereof are orthogonal to the back surface of the second printed circuit board, and the first concave groove or the second concave groove faces the back surface and is in parallel. A plurality of third piezoelectric bodies arranged in
The ultrasonic transducer according to claim 1. A first printed circuit board;
A front electrode is formed on the front surface on the ultrasonic radiation direction side, a back electrode is formed on the back surface opposite to the front surface, and an end on the front electrode side in the first side surface orthogonal to the front surface and the back surface. A first concave groove formed from the edge toward the edge on the back electrode side, and on the back electrode side from the edge on the front electrode side on the second side surface opposite to the first side surface A second concave groove formed toward the edge of the first printed circuit board, and a front surface and a rear surface are orthogonal to the surface of the first printed circuit board, and the first side surface or the second side surface faces the surface. A plurality of first piezoelectric bodies arranged in parallel with each other;
It has the same structure as the first piezoelectric body, and the front surface and the back surface thereof are orthogonal to the back surface opposite to the front surface of the first printed circuit board, and the first concave groove or the second concave groove. A plurality of second piezoelectric bodies arranged in parallel so as to face the back surface,
Formed on the front surface of the first printed circuit board and housed in the first or second groove of the first piezoelectric body, and the front electrode or back surface of the first piezoelectric body, respectively. A plurality of first electrode leads coupled directly or indirectly to one of the electrodes;
Formed on the back surface of the first printed circuit board, housed in the first or second groove of the second piezoelectric body, and the front electrode or back surface of the second piezoelectric body, respectively. Comprising an ultrasonic transducer having a plurality of second electrode leads coupled directly or indirectly to one of the electrodes;
Ultrasonic probe characterized by.