JP5454890B2 - Ultrasonic probe and method for manufacturing ultrasonic probe - Google Patents

Description

  The present invention relates to an ultrasonic probe used in an ultrasonic diagnostic apparatus and an ultrasonic flaw detection apparatus, and a method for manufacturing the ultrasonic probe.

  There are ultrasonic probes used in ultrasonic diagnostic apparatuses, ultrasonic flaw detection apparatuses, and the like. As an application of the ultrasonic probe, there is a two-dimensional array probe having a two-dimensional array structure. The two-dimensional array probe has a plurality of transducers arranged two-dimensionally. In order to realize a two-dimensional array structure, it is important to extract signal leads from each transducer. For example, in Patent Document 1, a signal lead is arranged by arranging a substrate corresponding to the transducer arrangement on the back surface of the transducer and joining a signal lead on the back surface of the transducer to a flexible printed circuit (FPC). A pulling structure is disclosed. Patent Document 2 and Patent Document 3 have a structure in which an FPC is arranged on the back surface of a two-dimensionally arranged vibrator and a signal lead on the back face of the vibrator is joined to the FPC to draw out the vibration lead. It is disclosed. Patent Document 4 discloses a structure in which an integrated circuit (IC) is arranged on the back surface of a vibrator instead of the FPC.

JP 2001-27451 A US Pat. No. 5,311,095 US Pat. No. 5,267,221 US Pat. No. 6,551,248

  In recent years, for example, as shown in Patent Document 4, a two-dimensional array probe has been devised in which a plurality of vibrators and an electric circuit such as an IC are electrically connected to perform electrode lead extraction and electric signal processing. In general, as the aperture diameter (number of vibrators) increases, the yield of the vibrator group tends to deteriorate and the cost tends to increase. In addition, when an IC is arranged on the back surface of the transducer group instead of the FPC, the area of the connection surface between the transducer group and the IC becomes large. At that time, if both opposing surfaces are not flat, an electrical connection failure occurs and the yield of the ultrasonic probe deteriorates. Further, as the opening diameter increases, the area of the IC must be increased. For this reason, the yield of the IC itself deteriorates and the cost increases. For these reasons, it is very difficult to realize an ultrasonic probe having a large aperture diameter.

  An object of the present invention is to realize an improvement in the yield of an ultrasonic probe in an ultrasonic probe in which a plurality of vibrators arranged in a two-dimensional array and an electric circuit are electrically connected and an ultrasonic probe manufacturing method. is there.

  An ultrasonic probe according to a first aspect of the present invention includes a plurality of transducers arranged at a first pitch, a substrate having an insulating property, and the plurality of transducers arranged at a surface of the substrate at the first pitch. A plurality of first conductive pads respectively electrically connected to the plurality of first conductive pads, and a plurality of second conductive pads arranged on the back surface of the substrate at a second pitch shorter than the first pitch and electrically connected to the plurality of first conductive pads, respectively. A wiring board having a conductive pad; and a plurality of electric circuits electrically connected to the plurality of second conductive pads.

  An ultrasonic probe manufacturing method according to a second aspect of the present invention is a plurality of circuits that form a transducer block and have a plurality of first surfaces, wherein each of the plurality of first surfaces includes a plurality of terminals. A substrate having a second surface and a third surface provided with a plurality of connection areas, wherein the second surface is arranged at a first pitch along at least one direction. A plurality of second conductive pads arranged in a second pitch shorter than the first pitch along the at least one direction. The transducer block and the second surface are faced to each other, and the plurality of first surfaces and the plurality of connection areas are faced to each other, and Electrical connection between the electric circuit and the wiring board , In order to form a plurality of second conductor and the same number of transducers, cut at the first pitch along the resonator block in the at least one direction, comprising the.

  An ultrasonic probe according to a third aspect of the present invention includes a plurality of transducers formed by cutting a transducer block at a first pitch, a first surface facing the plurality of transducers, and the first A wiring board having a second surface opposite to the surface, wherein the first surface has a plurality of first conductive pads electrically connected to the plurality of vibrators and arranged at the first pitch, respectively. The second surface is provided with a plurality of connection areas, and each of the plurality of connection areas has a plurality of second conductive pads arranged at a second pitch shorter than the first pitch. A wiring board to be formed; and a plurality of electric circuits each having a plurality of terminals electrically connected to the plurality of second conductive pads.

  According to the present invention, in an ultrasonic probe in which a plurality of transducers arranged in a two-dimensional array and an electric circuit are electrically connected and an ultrasonic probe manufacturing method, the yield of the ultrasonic probe is improved.

1 is an exploded perspective view of an ultrasonic probe according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the ultrasonic probe viewed from the vertical direction of FIG. 1. The top view which looked at the IC layer of FIG. 2 from the top along the height direction. The top view which looked at FPC of FIG. 2 from the bottom along the height direction. The enlarged view which looked at FPC of FIG. 2 from the vertical direction. The enlarged plan view which looked at FPC of FIG. 2 from the top along the height direction. The enlarged plan view which looked at FPC of FIG. 2 from the bottom along the height direction. The figure which shows the flow of the manufacturing process of the ultrasonic probe of FIG. The top view which looked at the IC layer of the ultrasonic probe which concerns on the modification 1 of this embodiment from the top along the height direction. Sectional drawing which looked at the ultrasonic probe which concerns on the modification 2 of this embodiment from the vertical direction. The figure which shows the flow of the manufacturing process of the ultrasonic probe of FIG.

  Hereinafter, an ultrasonic probe and an ultrasonic probe manufacturing method according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is an exploded perspective view of an ultrasonic probe 1 according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the ultrasonic probe 1 viewed from the longitudinal direction of FIG. As shown in FIGS. 1 and 2, the ultrasonic probe 1 according to the present embodiment includes a transducer layer 10 having a large aperture diameter. An acoustic matching layer 20 is bonded to the surface of the transducer layer 10. A back acoustic layer 30 is bonded to the back surface of the transducer layer 10. A flexible printed wiring board 40 (hereinafter referred to as FPC) is bonded to the back surface of the back acoustic layer 30. An IC layer 50 is bonded to the back surface of the FPC 40. As shown in FIG. 2, the transducer layer 10, the acoustic matching layer 20, the back acoustic layer 30, the FPC 40, and the base 60 for supporting the IC layer 50 are joined to the back surface of the IC layer 50. Thus, the ultrasonic probe 1 has a laminated structure in which the acoustic matching layer 20, the transducer layer 10, the back acoustic layer 30, the FPC 40, and the IC layer 50 are laminated along the height direction.

  The transducer layer 10 receives drive signals (electrical signals) supplied from an ultrasonic diagnostic apparatus (not shown) via the IC layer 50, generates ultrasonic waves, and receives ultrasonic waves reflected by the subject. To generate an echo signal (electric signal). The generated echo signal is supplied to the ultrasonic diagnostic apparatus via the IC 50. The vibrator layer 10 includes a plurality of vibrators 11 arranged in a two-dimensional manner along the vertical direction and the horizontal direction. The vibrators 11 are arranged at the arrangement pitch PY1 along the horizontal direction. The arrangement pitch of the vibrators 11 along the vertical direction may be the same as or different from the arrangement pitch PY1 along the horizontal direction. Hereinafter, for the sake of specific description, it is assumed that the arrangement pitch of the vibrators 11 along the horizontal direction and the arrangement pitch of the vibrators 11 along the vertical direction are substantially the same. Further, it is assumed that the width of the vibrator 11 along the horizontal direction and the width of the vibrator 11 along the vertical direction are substantially the same.

  Each vibrator 11 includes a piezoelectric body 13 that is polarized along the height direction, a signal electrode 15 that is formed on the back surface of the piezoelectric body 13, and a ground electrode 17 that is formed on the surface of the piezoelectric body 13. The piezoelectric body 17 is formed of, for example, a two-component or three-component piezoelectric ceramic or a piezoelectric single crystal. The signal electrode 15 and the ground electrode 17 are formed, for example, by metal plating or sputtering with silver or gold.

  The acoustic matching layer 20 suppresses the reflection of ultrasonic waves caused by the difference between the acoustic impedance of the subject and the acoustic impedance of the transducer layer 10. The acoustic matching layer 20 includes a plurality of acoustic matching elements 21 arranged in a two-dimensional manner along the vertical direction and the horizontal direction. The back surface of the acoustic matching element 21 is bonded to the surface of the vibrator. That is, the acoustic matching elements 21 are arranged at substantially the same arrangement pitch as the transducer 11 (the arrangement pitch P1 in the horizontal direction). The acoustic matching element 21 is formed of, for example, an acoustic matching material made of a conductive material or an insulating material. Although only one acoustic matching layer 20 is shown in FIGS. 1 and 2, the present embodiment is not limited to this. For example, two, three, or more acoustic matching layers 20 may be disposed on the transducer layer 10. Typically, a biological contact layer (not shown) is bonded to the surface of the acoustic matching layer 20. The living body contact layer is a lens made of silicone rubber or the like having acoustic impedance close to that of a living body.

  The back acoustic layer (backing material) 30 has a plurality of back acoustic elements 31 arranged two-dimensionally along the vertical direction and the horizontal direction. The surface of the back acoustic element 31 is joined to the back surface of the transducer 11, that is, the signal electrode 15. That is, the back acoustic elements 31 are arranged at substantially the same arrangement pitch as that of the transducers 11 (the arrangement pitch PY1 in the horizontal direction).

  The back acoustic element 31 is formed of an acoustic damping material such as an insulating material or a conductive material. When the back acoustic element 31 is formed of an insulating material, for electrical connection between the vibrator 11 and the FPC 40, typically, a conductive wire 33 (hereinafter referred to as the signal electrode 15 and the FPC 40) is connected to each back acoustic element 31. , Will be referred to as signal leads). On the other hand, when the back acoustic element 31 is formed of a conductive material, the vibrator 11 and the FPC 40 are electrically connected via the back acoustic element 31. Therefore, when the back acoustic element 31 is formed of a conductive material, the signal lead 33 does not need to be embedded in the back acoustic element 31. In the following, the back acoustic element 31 is formed of an insulating material for specific description. That is, the vibrator 11 and the FPC 40 are electrically connected via the signal lead 33 embedded in the back acoustic element 31.

  The IC layer 50 has a plurality of ICs 51 arranged on the base 60 along the horizontal direction and the vertical direction. The IC 51 is an electric circuit in which a plurality of electronic components are integrated on a rigid semiconductor substrate. The size of the IC 51 is not particularly limited. However, preferably, a smaller area is better in order to improve the manufacturing yield of the IC 51 itself. In other words, it is not necessary to increase the area of the IC 51 such that the manufacturing yield of the IC 51 itself deteriorates as compared to the standard IC manufacturing yield.

  FIG. 3 is a plan view of the IC layer 50 as viewed from above along the height direction. The IC 51 transmits and receives electrical signals to and from the vibrator 11. The ICs 51 are arranged on the base 60 at an arrangement pitch PY3 with a gap GYI along the horizontal direction, and are arranged on the base 60 with an arrangement pitch PT3 at a gap GTI along the vertical direction. The interval GYI and the interval GTI, and the arrangement pitch PY3 and the arrangement pitch PT3 may be the same or different, but are assumed to be substantially the same in order to specifically describe the following.

  Here, in order to explain the gap between the ICs 51 in more detail, the IC row 55 is considered. The IC row 55 is composed of a plurality of ICs 51 arranged in a row at intervals GTI along the vertical direction. The plurality of IC rows 55 are arranged on the back surface of the FPC 40 with a gap GYI and are electrically connected to the FPC 40. The gaps between the IC rows 55 adjacent along the horizontal direction (the gaps between the ICs 51) are aligned along the vertical direction. The IC row 55 may be composed of a plurality of ICs 51 arranged in a row along the horizontal direction. In this case, the gap between the IC rows 55 adjacent along the vertical direction is aligned along the vertical direction. That is, the ICs 51 are arranged with a lattice-like gap having a width GYI along the horizontal direction and a width GTI along the vertical direction, and the gaps between the ICs 51 are aligned along the horizontal direction and the vertical direction. ing. In other words, the gap between the adjacent ICs 51 has a linear shape along the alignment direction (both the horizontal direction and the vertical direction).

  Each IC 51 has a plurality of electrical terminals on its surface. The electrical terminal 53 is made of a conductive material. The electrical terminals 53 are arranged at an arrangement pitch PT2 that is narrower than the arrangement pitch PT1. Further, the first connection portions 53 are arranged at an arrangement pitch PT2 that is narrower than the arrangement PT1 (the arrangement pitch of the transducers 11 along the vertical direction) along the vertical direction. The arrangement pitch PY2 and the arrangement pitch PT2 may be the same or different, but are assumed to be substantially the same for the following description.

  The FPC 40 includes a flexible insulating substrate 41 on which wiring is printed. The surface of the insulating substrate 41 faces the plural vibrators 11 and is used for electrical connection with the plural vibrators 11. The back surface of the insulating substrate 41 is located on the opposite side of the surface, faces the plurality of ICs 51, and is used for electrical connection with the plurality of ICs 51.

  The FPC 40 has a plurality of pads 42 electrically connected to the plurality of vibrators 11 on the surface thereof. The pad 42 is an electric pad (hereinafter referred to as an upper electric pad) formed on the surface of the FPC 40 and having a conductive material. The total number of upper electrical pads 42 on the FPC 40 is the same as the total number of transducers 11 included in the transducer layer 10. The upper electric pads 42 are arranged at an arrangement pitch PT1 that is substantially the same as that of the vibrator 11. Bumps 43 are provided on the upper electric pad 42. The bump 43 is joined to the signal lead 33 extending from the signal electrode 15 on the back surface of the back acoustic element 31. By arranging the upper electric pads 42 and the vibrators 11 at the same arrangement pitch, the upper electric pads 42 and the vibrators 11 are bump-connected in a one-to-one manner via the bumps 43. The FPC 40 and the plurality of vibrators 11 are electrically connected by bump-connecting the upper electric pad 42 and the vibrator 11.

  FIG. 4 is a plan view of the FPC 40 as viewed from below. As shown in FIG. 4, a plurality of connection areas Z <b> 1 and non-connection areas Z <b> 2 are provided on the back surface of the FPC 40. The plurality of connection areas Z <b> 1 are areas provided for electrical connection with the plurality of ICs 51 on the back surface of the FPC 40. The non-connection area Z2 is an area other than the plurality of connection areas Z1 on the back surface of the FPC 40. That is, the non-connection area Z2 is an area that is not used for electrical connection with the plurality of ICs 51. The connection areas Z1 are arranged at substantially the same arrangement pitch PY3 as the IC 51 along the horizontal direction, and are arranged at substantially the same arrangement pitch PT3 as the IC 51 along the vertical direction.

  A plurality of pads 44 arranged two-dimensionally are formed in each connection zone Z1. The pad 44 is an electrical pad formed on the back surface of the FPC 40 and having a conductive material (hereinafter referred to as a lower electrical pad). The total number of lower electrical pads 44 included in the FPC 40 is the same as the total number of vibrators 11 included in the vibrator layer 10, and the same as the total number of electrical terminals 53 included in the IC layer 50. The lower electric pads 44 are arranged at the same arrangement pitch PY2 as the electric terminals 53 along the horizontal direction, and are arranged at the same arrangement pitch PT2 as the electric terminals 53 along the vertical direction. Bumps 45 are provided on the lower electric pads 44. Electrical terminals 53 are joined to the bumps 45. By arranging the lower electric pads 44 and the electric terminals 53 at the same arrangement pitch, the lower electric pads 44 and the electric terminals 53 are bump-connected in a one-to-one relationship. The FPC 50 and the plurality of ICs 51 are electrically connected by the bump connection between the lower electrical pad 44 and the electrical terminal 53.

  The upper electrical pads 42 and the lower electrical pads 44 on the FPC 40 are electrically connected in a one-to-one manner within the FPC 40. Here, the electrical connection between the upper electrical pad 42 and the lower electrical pad 44 will be described in detail with reference to FIGS. 5, 6, and 7. FIG. 5 is an enlarged view of the FPC 40 viewed from the vertical direction. FIG. 6 is an enlarged plan view of the FPC 40 viewed from above along the height direction. FIG. 7 is an enlarged plan view of the FPC 40 viewed from below along the height direction. As shown in FIGS. 5, 6, and 7, the upper electrode pad 42 and the printed wiring 46 are integrally printed on the surface of the wiring board 41 of the FPC 40. Bumps 43 are formed on the upper electrode pad 42. The upper electrode pads 42 and the bumps 43 are arranged at an arrangement pitch PY1 along the horizontal direction. A lower electrode pad 44 is printed on the back surface of the wiring substrate 41 of the FPC 40. Bumps 45 are formed on the lower electrode pad 44. The lower electrode pads 44 and the bumps 45 are arranged at an arrangement pitch PY2 along the horizontal direction. The wiring board 41 is formed with a through wiring 47 that penetrates the wiring board 41 vertically. The through wiring 47 is disposed so as to contact the printed wiring 46 and the lower electric pad 44. Typically, the through wiring 47 is formed by filling a through hole formed so as to vertically penetrate the wiring substrate 41 with a conductive material. The through wires 47 are arranged at the same arrangement pitch PY2 as the lower electrode pads 44 along the horizontal direction. As described above, the upper electrode pad 42 and the lower electrode pad 44 are electrically connected one-on-one via the printed wiring 46 and the through wiring 47.

  With the above configuration, the plurality of vibrators 11 and the plurality of ICs 51 are electrically connected through the FPC 40.

  Next, a method for manufacturing the ultrasonic probe 1 will be described. FIG. 8 is a diagram showing the flow of the manufacturing process of the ultrasonic probe 1. As shown in FIG. 8, first, a vibrator block, FPC 40, and a plurality of ICs 51 are formed (step SA1). The vibrator block is a laminated body in which a flat plate-like back acoustic material plate, a piezoelectric material plate, and an acoustic matching material plate are bonded. Electrodes are formed on the front and back surfaces of the piezoelectric material plate by sputtering, plating, or the like. On one surface (front surface) of each IC 51, electrical terminals 53 for electrical connection with the FPC 40 are formed at an array pitch PY2. Each IC 51 is formed in a size with a good manufacturing yield and a good junction yield with the FPC 40. On the surface of the FPC 40, a plurality of upper electric pads 42 for electrically connecting to the plurality of vibrators 11 are formed at a predetermined arrangement pitch PY1. The area on the back surface of the FPC 40 to which the IC 51 is electrically connected is set to the connection area Z1. The position, size, shape, arrangement pitch, and arrangement interval of the connection area Z1 are set to match the arrangement position, size, shape, arrangement pitch, and arrangement interval of the IC 51 that is electrically connected. In each connection area Z1, lower electric pads 44 are formed at the same arrangement pitch PY2 as the electric terminals 53. The lower electric pad 44 and the upper electric pad 42 are electrically connected one-to-one via the wiring on the FPC 40.

  Next, the vibrator block, the FPC 40, and the plurality of ICs 51 are electrically connected (step SA2). Specifically, the surface on the back acoustic material plate side of the transducer block and the surface of the FPC 40 face each other, and the surface of the plurality of ICs 51 faces the plurality of connection areas. The electrical terminals 53 and the lower electrical pads 44 are bump-connected via the bumps 45 so that the electrical terminals 53 and the lower electrical pads 44 are electrically connected on a one-to-one basis. After the bump connection, resin is filled and bonded to the gap between the vibrator block and the FPC 40 and the gap between the FPC 40 and the plurality of ICs 51.

  Next, the transducer block is diced with a dicing blade at the same arrangement pitch PY1 as the electric pads 42, and a plurality of transducers 11, a plurality of acoustic matching elements 21, and a plurality of back acoustic elements 31 are formed (step SA3). At this time, dicing (cutting) is performed so that the dicing position is located between the upper electric pads 42.

  After dicing, the back surfaces of the plurality of ICs 51 are joined to the base 60 (step SA4). After joining to the base 60, the ultrasonic probe 1 is completed by filling the grooves between the vibrators 11 with resin or the like.

  According to the ultrasonic probe 1 and the method of manufacturing the ultrasonic probe 1, the following effects can be obtained. As described above, in the ultrasonic probe 1, the FPC 40 is disposed between the plurality of transducers 11 and the plurality of ICs 51, and the plurality of transducers 11 and the plurality of ICs 51 are electrically connected via the FPC 40. In order to allow a plurality of ICs 51 to be bonded to the FPC 40, the arrangement of the lower electrical pads 44 on the back surface of the FPC 40 is set in accordance with the arrangement of the ICs 51. Thereby, in order to realize the vibrator layer 10 having a large opening diameter, a plurality of small-area ICs 51 can be bonded to the FPC 40 instead of the large-area IC. Since the IC 51 has a small area, the IC 51 is not distorted, and the manufacturing yield of the IC 51 can be improved. Accordingly, it is possible to reduce the occurrence of electrical connection failure that occurs when the surface of the IC 51 and the back surface of the FPC 40 are not flat. Therefore, this embodiment can improve the yield in the electrical connection between the IC 51 and the FPC 40 as compared with the prior art.

  Thus, according to this embodiment, in the ultrasonic probe in which a plurality of transducers arranged in a two-dimensional manner and an electric circuit are electrically connected and the method for manufacturing the ultrasonic probe, the yield of the ultrasonic probe is improved. It becomes possible. Further, it is possible to reduce the manufacturing cost of the ultrasonic probe as the yield is improved.

  In the present embodiment, the IC 51 and the FPC 40 are bump-connected in order to electrically connect the IC 51 and the vibrator 11, but the present embodiment is not limited to this. That is, if the IC 51 and the vibrator 11 are electrically connected, the IC 51 and the FPC 40 may be joined by any existing method.

  In the present embodiment, the IC 51 is mounted as an electric circuit, but the present embodiment is not limited to this. For example, instead of the IC 51, a plurality of electronic components may be mixedly mounted, and an electrical circuit unit having a BGA (ball grid array) structure may be mounted at an electrical connection portion with the wiring board.

  further. In the present embodiment, a three-layer structure is adopted as the ultrasonic probe 1, but the present embodiment is not limited to this. For example, what is necessary is just the structure which has the electrical terminal for electrical connection in the opposing surface of FPC40.

  Further, the present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage.

(Modification 1)
In the present embodiment, the size and shape of the IC 51 electrically connected to the FPC 40 are the same. However, this embodiment is not limited to this. In the present embodiment, the size and shape of the IC 51 may not be the same. Hereinafter, in Modification 1, an ultrasonic probe in which the sizes of the ICs 51 are not the same and a manufacturing method thereof will be described. In the following description, components having substantially the same functions as those of the present embodiment are denoted by the same reference numerals, and redundant description will be given only when necessary.

  FIG. 9 is a plan view of the IC layer 500 according to Modification 1 as viewed from above along the height direction. As shown in FIG. 9, the IC layer 510 includes a plurality of ICs 510 having a plurality of shapes and sizes. Due to the difference in size and shape, different numbers of electrical terminals 53 are formed in each IC 510. A plurality of connection areas respectively corresponding to the plurality of ICs 510 are provided on the back surface of the FPC 40. The position, size, shape, arrangement pitch, and arrangement interval of the connection area are set to coincide with the arrangement position, size, shape, arrangement pitch, and arrangement interval of the IC 51 that is electrically connected. Each connection area is formed with a plurality of lower electrical pads 44 for bump connection with the electrical terminals 53 on the IC 510 facing each other. The number and arrangement pitch of the lower electric pads 44 are set to be the same as the number and arrangement pitch of the electric terminals 53 on the IC 510 facing each other. As a result, a plurality of ICs 510 and FPCs 40 having different sizes and shapes can be electrically connected, and thus the plurality of ICs 510 and the plurality of vibrators 11 can be electrically connected.

  Note that the ultrasonic probe according to the first modification can be manufactured based on the same manufacturing process as that in FIG. 8 except that the shape and size of the IC 510 and the connection area are different. Therefore, the description of the method for manufacturing the ultrasonic probe according to the modification 1 is omitted.

  With the above configuration, the ultrasonic probe according to the first modification has a structure in which a plurality of ICs 510 having different sizes and shapes and the FPC 40 can be electrically connected. Therefore, in the first modification, it is not necessary to unify the shape and size of the individual ICs 510 that are electrically connected to the FPC 40. Thus, according to the first modification, an ultrasonic probe having a large aperture diameter and a manufacturing method thereof can be realized regardless of the size and shape of the IC 510.

(Modification 2)
Hereinafter, an ultrasonic probe and a manufacturing method thereof according to Modification 2 of the present embodiment will be described. In the following description, components having substantially the same functions as those of the present embodiment are denoted by the same reference numerals, and redundant description will be given only when necessary.

  FIG. 10 is a cross-sectional view of the ultrasonic probe 100 according to the second modification viewed from the vertical direction. As shown in FIG. 10, the ultrasonic probe 100 according to Modification 2 is a convex probe in which the ultrasonic radiation surface formed by the plurality of transducers 11 has a convex shape. Specifically, the ultrasonic probe 100 includes an acoustic matching layer 20, a transducer layer 10, a back acoustic layer 30, an FPC 40, an IC layer 50, and a base 61. The base 61 is raised along the height direction. An FPC 40 is disposed on the base 61 via the IC 51. The FPC 40 is a flexible wiring board on which wiring is printed as described above. By bending the FPC 40 along the shape of the base 61, the ultrasonic radiation surfaces of the plurality of transducers 11 can be made convex. The base 61 has a half prism shape and includes a plurality of planes (side surfaces of the half prism) extending along the vertical direction. The IC 51 is bonded to this plane. In addition, the base 61 in FIG. 10 has a structure in which three ICs 51 are joined in a plane defined by the vertical direction and the height direction, but the second modification is not limited thereto. For example, four or more ICs 51 may be joined in a plane defined by the vertical direction and the height direction.

  Hereinafter, a structure for enabling the FPC 40 to be bent will be described. In order to be able to bend the FPC 40, as shown in FIG. 3, the gap between the ICs 51 must be aligned along at least one direction (in FIG. 3, at least one of the horizontal direction and the vertical direction). In other words, as shown in FIG. 9, when the gap between the ICs 51 is not aligned in either the horizontal direction or the vertical direction, the FPC 40 cannot be bent. More specifically, the gap between the adjacent ICs 51 has a linear shape along the alignment direction, and the width GYI between the adjacent ICs 51 must be the same along the direction orthogonal to the alignment direction. By satisfying this requirement, the FPC 40 to which the plurality of ICs 51 are electrically connected can be bent along the height direction.

  Next, a method for manufacturing the ultrasonic probe 100 according to Modification 2 will be described. FIG. 11 is a diagram showing the flow of the manufacturing process of the ultrasonic probe 100. Note that steps SB1 to SB3 in FIG. 11 are the same as steps SA1 to SA3 in FIG.

  In step SB3, after the plurality of vibrators 11 and the like are formed by dicing, the FPC 40 is bent along the height direction (that is, the vertical direction of the front surface and the back surface of the FPC 40). (Step SB4). Thereby, the ultrasonic radiation surface formed by the plurality of transducers 11 can be formed in a convex shape.

  After the FPC 40 is bent, the plurality of ICs 51 are joined to the base 61 (step SB5). The shape of the base 61 is designed according to the size and number of ICs 51. For example, as shown in FIG. 10, when three ICs 51 are arranged along the horizontal direction, the base 61 is formed with three planes along the horizontal direction. After joining the IC 51 to the base 61, the grooves between the vibrators 11 are filled with resin or the like, whereby the ultrasonic probe 100 is completed.

  In Modification 2, the FPC 40 is bent so as to rise along the height direction, that is, so that the ultrasonic radiation surface has a convex shape. However, the modified example 2 is not limited to this. For example, the FPC 40 may be bent so as to be depressed along the height direction, that is, the ultrasonic radiation surface has a concave shape.

  According to the ultrasonic probe 100 and the manufacturing method thereof, the following effects can be obtained. Conventionally, when an IC and a plurality of vibrators are electrically connected, the IC is disposed on the back surface of the plurality of vibrators without an FPC. In order to realize a large aperture diameter in such a conventional structure, the IC must have a large area. On the other hand, since IC has rigidity, it cannot be bent. Therefore, the conventional structure cannot realize an ultrasonic radiation surface having a large opening diameter which is not flat (typically, an ultrasonic radiation surface having a convex shape).

  In the second modification, in order to realize an ultrasonic radiation surface having a large aperture that is not flat (typically, an ultrasonic radiation surface having a convex shape), a flexible FPC 40 is employed as a wiring board, The FPC 40 is bent along the height direction by electrically connecting the IC 51 to the FPC 40 so that the gaps are aligned. Thereby, it is possible to realize a convex probe having a large opening diameter, which cannot be realized by the conventional structure.

  In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

  As described above, according to the present invention, in the ultrasonic probe in which a plurality of transducers arranged in a two-dimensional manner and an electric circuit are electrically connected and the method of manufacturing the ultrasonic probe, the yield of the ultrasonic probe is improved. Can do.

  DESCRIPTION OF SYMBOLS 1 ... Ultrasonic probe, 10 ... Vibrator layer, 11 ... Vibrator, 13 ... Piezoelectric body, 15 ... Signal electrode, 17 ... Ground electrode, 20 ... Acoustic matching layer, 21 ... Acoustic matching element, 30 ... Back acoustic layer, 31 ... back acoustic element, 33 ... signal lead, 40 ... FPC, 41 ... wiring board, 42 ... upper electric pad, 43 ... bump, 44 ... lower electric pad, 45 ... bump, 50 ... IC layer, 51 ... IC, 53 ... Electric terminal, 60 ... Base

Claims (11)

A plurality of vibrators arranged at a first pitch;
A substrate having insulation properties, a plurality of first conductive pads arranged on the surface of the substrate at the first pitch and electrically connected to the plurality of vibrators, and the second pitch shorter than the first pitch. A wiring substrate having a plurality of second conductive pads arranged on the back surface of the substrate and electrically connected to the plurality of first conductive pads, respectively.
A plurality of electrical circuits electrically connected to the plurality of second conductive pads;
An ultrasonic probe comprising :
The wiring board has flexibility,
An ultrasonic probe characterized by that.   The wiring board includes a plurality of connection areas provided for electrical connection with the plurality of electrical circuits and a non-connection area not provided for electrical connection with the plurality of electrical circuits on the back surface. The described ultrasonic probe.   The ultrasound probe according to claim 2, wherein the plurality of connection areas are arranged on the back surface at the same third pitch as the plurality of electric circuits.   4. The ultrasonic probe according to claim 3, wherein each of the plurality of connection areas includes the second conductive pads arranged at the second pitch. A plurality of electric circuit arrays arranged at predetermined intervals along the first direction are electrically connected to the wiring board,
Each of the plurality of electric circuit rows is composed of a plurality of electric circuits arranged in a line along a second direction substantially orthogonal to the first direction among the plurality of electric circuits.
The predetermined interval is substantially the same as the width of the non-connection area along the first direction.
The ultrasonic probe according to claim 3.   The wiring board is bent so that an ultrasonic radiation surface formed by the plurality of vibrators is raised or depressed in a third direction substantially orthogonal to the first direction and the second direction. 5. The ultrasonic probe according to 5.   The ultrasonic probe according to claim 1, wherein each of the plurality of electric circuits is electrically connected to the wiring board at predetermined intervals.   The ultrasonic probe according to claim 1, wherein the wiring board has a printed wiring.   The ultrasonic probe according to claim 1, wherein each of the plurality of electric circuits is an integrated circuit in which a plurality of electronic components are integrated on a semiconductor substrate.   The ultrasonic probe according to claim 1, wherein the plurality of first conductive pads and the plurality of second conductive pads are connected to each other by wiring in the substrate. Forming a transducer block,
A plurality of circuits having a plurality of first surfaces, each of the plurality of first surfaces forming a plurality of electrical circuits having a plurality of terminals;
A substrate having a second surface and a third surface provided with a plurality of connection areas, wherein the second surface includes a plurality of first conductive pads arranged at a first pitch along at least one direction. Each of the plurality of connection areas forms a wiring substrate having a plurality of second conductive pads arranged at a second pitch shorter than the first pitch along the at least one direction;
The transducer block, the plurality of electric circuits, and the wiring board are arranged so that the transducer block and the second surface face each other, and the plurality of first surfaces and the plurality of connection areas face each other. Electrical connection and
Cutting the vibrator block at the first pitch along the at least one direction in order to form the same number of vibrators as the plurality of second conductors;
An ultrasonic probe manufacturing method comprising :
An interval between two connection areas adjacent along the at least one direction of the plurality of connection areas has substantially the same width,
The plurality of electric circuits are disposed on the third surface with the substantially same width along the at least one direction,
Bending the wiring board in a direction perpendicular to the second surface and the third surface;
A method of manufacturing an ultrasonic probe.

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