JP5889121B2 - Ultrasonic transducer - Google Patents

Description

  The present invention relates to an ultrasonic transducer in which a transducer part is disposed on one surface of a substrate.

  2. Description of the Related Art Conventionally, an ultrasonic transducer is used in an ultrasonic diagnostic apparatus that irradiates ultrasonic waves and creates a diagnostic image based on an echo signal reflected from a subject.

  As this ultrasonic transducer, a capacitive ultrasonic transducer (C-MUT (Capacitive Micromachined Ultrasonic Transducer)) and a piezoelectric ultrasonic transducer (P-MUT (Piezoelectric Micromachined Ultrasonic Transducer)) are known. ing. Examples of the C-MUT technique include, for example, Japanese Patent Application Laid-Open No. 2008-119318 and Japanese Patent Application Laid-Open No. 2010-272756, and examples of a technique combining the C-MUT and the P-MUT include, for example, No. 229328.

  FIG. 10 is a cross-sectional view showing an example of a conventional C-MUT.

  The C-MUT has a first insulating layer 111, a lower electrode 112, a second insulating layer 113, a gap 114, a third insulating layer 115, an upper electrode 116, and a protective film 117 (on a substrate 110 made of a silicon wafer or the like. The third insulating layer 115, the upper electrode 116, and the protective film 117 over the gap 114 are collectively referred to as a membrane) to form a vibrator portion. Here, the side on which the vibrator part of the substrate 110 is formed is referred to as the upper surface side, and the opposite side is referred to as the lower surface side.

  The P-MUT is obtained by arranging a piezoelectric element in place of the gap 114 in the C-MUT.

  Further, on the lower surface side of the substrate 110, a backing material 123 for absorbing unnecessary vibrations and a housing 124 provided so as to surround the outer periphery of the backing material 123 to hold the backing material 123 are arranged. ing. Here, the portion where the backing material 123 is disposed is an opposite portion across the substrate 110 in the region where the gap 114 is provided. Further, the portion where the housing 124 is disposed is an opposite side portion of the region surrounding the region where the gap 114 is provided with the substrate 110 interposed therebetween.

  Then, by applying a voltage between the lower electrode 112 and the upper electrode 116, the membrane above the gap 114 vibrates and transmits ultrasonic waves. In addition, when an ultrasonic wave is received, the membrane vibrates and the distance between the lower electrode 112 and the upper electrode 116 changes, and the voltage between the electrodes changes to be detected as an electrical signal.

  Incidentally, since a silicon wafer or the like is used as the substrate 110, wiring for supplying electricity to the lower electrode 112 and the upper electrode 116 is connected on the upper surface side for transmitting and receiving ultrasonic waves.

  That is, the upper electrode 116 is partly exposed to the outside from the protective film 117 in the region where the gap 114 is not provided, for example, on the left side of FIG. And is connected to the upper electrode drive wiring 131.

  Similarly, the lower electrode 112 is partially exposed to the outside from the second insulating layer 113, the third insulating layer 115, the protective film 117, etc. in the region where the gap 114 is not provided, for example, on the right side of FIG. An electrode pad is configured, and the electrode pad is connected to the lower electrode drive wiring 132 via the solder 135.

  The portion of the upper electrode drive wiring 131 that faces the side surface of the substrate 110 is covered with an insulating outer skin 131a, and similarly, the portion of the lower electrode drive wiring 132 is also covered with an insulating outer skin 132a.

  In addition, the connection portion of the upper electrode drive wiring 131 and the lower electrode drive wiring 132 is covered with insulation by a wiring protection member 133.

  However, if the wiring to the electrode is performed on the upper surface side of the substrate 110, the wiring portion protrudes higher than the membrane and becomes higher as shown in FIG. In such a structure, it is difficult to sufficiently bring the membrane into contact with the subject, and as a result, the transmission / reception efficiency of ultrasonic waves is reduced.

  Therefore, a configuration for dealing with such a problem will be described with reference to FIG. FIG. 11 is a cross-sectional view showing another example of a conventional C-MUT.

  In this example, wiring to the electrodes is performed on the lower surface side of the substrate 110. For this purpose, a substrate 110 with through-hole vias (through vias) is used as the substrate 110.

  That is, the substrate 110 is formed with through-hole vias 141, 142, and 143 which are vias penetrating in the thickness direction.

  The upper electrode 116 is exposed to the substrate 110 side and is electrically connected to the through-hole via 141. The lower electrode 112 is also exposed to the substrate 110 side and is connected to the through-hole via 142.

  On the lower surface side of the substrate 110, an upper electrode drive wiring 131 and a lower electrode drive wiring 132 are arranged. The upper electrode drive wiring 131 is electrically connected to the through-hole via 141 and thus electrically connected to the upper electrode 116. The lower electrode drive wiring 132 is electrically connected to the through-hole via 142 and similarly electrically connected to the lower electrode 112.

JP 2008-119318 A JP 2010-272956 A JP 2007-229328 A

  However, in the configuration shown in FIG. 11, spaces 123a and 123b are provided on the lower surface side of the substrate 110 where the backing material 123 is supposed to be disposed, and the upper electrode drive wiring 131 is provided in the space 123a and the lower portion in the space 123b. Electrode drive wirings 132 are arranged respectively. Therefore, in these spaces 123a and 123b, unnecessary vibrations cannot be absorbed by the backing material 123, and the acoustic characteristics are impaired and the resolution is lowered.

  In order to prevent the backing material 123 from being damaged, it is conceivable that the upper electrode driving wiring 131 and the lower electrode driving wiring 132 are disposed by providing a space in a portion where the housing 124 is to be disposed. In this case, a thin portion is generated in the housing 124 to reduce the strength, and a portion in which the housing 124 does not contact the backing material 123 is generated. Will not be stable.

  Thus, there is a need for an ultrasonic transducer that can absorb unnecessary vibration while ensuring contact with a subject.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an ultrasonic transducer that ensures contact with a subject and does not deteriorate the function of absorbing unnecessary vibration.

  In order to achieve the above object, an ultrasonic transducer according to an aspect of the present invention includes a substrate, one surface of the substrate, a lower electrode, a gap or a piezoelectric element, and the gap or the piezoelectric. An oscillator having an upper electrode facing the lower electrode across the element, a backing material disposed on the other surface of the substrate, and the other surface of the substrate so as to surround an outer periphery of the backing material And a housing for holding the backing material, a first conductive portion disposed on one side of the substrate and electrically connected to the upper electrode, and disposed on the other side of the substrate, the lower electrode A second conductive portion electrically connected to the first conductive portion; an upper electrode drive wiring electrically connected to the side surface of the first conductive portion; and a lower electrode drive electrically connected to the side surface of the second conductive portion. Wiring.

  According to the ultrasonic transducer of the present invention, the function of absorbing unnecessary vibrations is not lowered while ensuring contact with the subject.

1 is a perspective view showing the overall configuration of an ultrasonic transducer according to Embodiment 1 of the present invention. In the said Embodiment 1, AA sectional drawing of FIG. 1 at the time of comprising as C-MUT. In the said Embodiment 1, AA sectional drawing of FIG. 1 at the time of comprising as P-MUT. Sectional drawing which shows a mode that C-MUT was comprised on the board | substrate with a through-hole via in Embodiment 2 of this invention. Sectional drawing which shows a mode that the board | substrate which comprised C-MUT in the said Embodiment 2 is cut | disconnected by the part of a through-hole via. Sectional drawing which shows a mode that wiring was performed to the board | substrate cut | disconnected by the through-hole via part in the said Embodiment 2. FIG. Sectional drawing which shows a mode that C-MUT was comprised on the board | substrate with a blind via in Embodiment 3 of this invention. Sectional drawing which shows a mode that the board | substrate which comprised C-MUT in the said Embodiment 3 is cut | disconnected in the part of a blind via. Sectional drawing which shows a mode that wiring was performed to the board | substrate cut | disconnected in the part of the blind via in the said Embodiment 3. FIG. Sectional drawing which shows an example of the conventional C-MUT. Sectional drawing which shows the other example of the conventional C-MUT.

Embodiments of the present invention will be described below with reference to the drawings.
[Embodiment 1]

  1 to 3 show a first embodiment of the present invention, and FIG. 1 is a perspective view showing the overall configuration of an ultrasonic transducer.

  As shown in FIG. 1, the ultrasonic transducer 1 is configured by arranging an ultrasonic vibration part 3 on a housing part 2.

  The ultrasonic vibration unit 3 is configured by arranging a plurality of MUT elements 3a that are units for inputting and outputting drive control signals, and each MUT element 3a is formed with a plurality of MUT cells 3b that are vibration units.

  2 is a cross-sectional view taken along line AA of FIG. 1 when configured as a C-MUT. FIG. 2 shows an example in which a capacitive ultrasonic transducer (C-MUT (Capacitive Micromachined Ultrasonic Transducer)) is employed as the ultrasonic transducer 1.

  The C-MUT has a first insulating layer 11, a lower electrode 12, a second insulating layer 13, a gap 14 (this gap 14 is also referred to as a cavity) The three insulating layers 15, the upper electrode 16, and the protective film 17 (the third insulating layer 15, the upper electrode 16, and the protective film 17 on the gap 14 are collectively referred to as a membrane) are stacked to form the vibrator portion. It is a thing. Hereinafter, the side of the substrate 10 on which the vibrator part is formed is referred to as the upper surface side, and the opposite side is referred to as the lower surface side.

  First, the first insulating layer 11 is formed so as to cover the entire top surface of the substrate 10.

  Further, the second wiring pattern 22 as the second conductive portion is directly formed on the right side surface in FIG. 2 before forming the lower electrode 12 on the substrate 10 at the latest, and before forming the upper electrode 16 at the latest, on the right side in FIG. The first wiring pattern 21 as the first conductive portion is directly formed on the left side surface in FIG. These wiring patterns 21 and 22 are formed at least up to a position equivalent to the upper surface of the substrate 10. In the example shown in FIG. 2, the wiring patterns 21 and 22 are further formed up to a position equivalent to the lower surface of the substrate 10.

  The lower electrode 12 is formed so as to cover a region corresponding to the gap 14. In the example illustrated in FIG. 2, the lower electrode 12 extends rightward from the region corresponding to the gap 14 and is connected to the second wiring pattern 22. .

  The second insulating layer 13 is formed so as to cover the entire upper surface of the lower electrode 12 and the upper surface of the first insulating layer 11 exposed from the lower electrode 12.

  For example, a sacrificial layer having the same shape as the gap 14 is first formed on the upper surface of the second insulating layer 13, and then the third insulating layer 15 is formed. After the third insulating layer 15 is formed, the sacrificial layer is removed. As a result, the gap 14 is formed. The air gap 14 corresponds one-to-one with the MUT cell 3b serving as the above-described vibration unit.

  As described above, the third insulating layer 15 is formed so as to cover the entire upper surface of the second insulating layer 13 with the gap 14 interposed therebetween.

  Similar to the lower electrode 12, the upper electrode 16 is formed so as to cover a region corresponding to the gap 14, and faces the lower electrode 12 with the gap 14 interposed therebetween. In the example shown in FIG. 2, the upper electrode 16 extends to the left from the region corresponding to the gap 14 and is connected to the first wiring pattern 21.

  The protective film 17 is formed so as to cover the entire upper surface of the upper electrode 16 and the upper surface of the third insulating layer 15 exposed from the upper electrode 16.

  Each layer of the protective film 17 from the substrate 10 as described above is included in the ultrasonic vibration unit 3 shown in FIG.

  On the other hand, the housing part 2 shown in FIG. 1 includes a backing material 23 and a housing 24.

  That is, the backing material 23 for absorbing unnecessary vibration is disposed on the lower surface side of the substrate 10 corresponding to the region where the gap 14 is provided.

  Further, in order to hold the backing material 23, a housing 24 is provided so as to surround the outer periphery of the backing material 23. Therefore, the portion where the housing 24 is disposed is an opposite side portion of the region surrounding the region where the air gap 14 is provided (therefore, the region where the air gap 14 is not provided) sandwiching the substrate 10.

  As an actual manufacturing process, the housing 24 may be disposed first, and then the backing material 23 may be filled in the housing 24.

  As described above, wiring is performed on the ultrasonic transducer 1 in which the housing part 2 is disposed in the ultrasonic vibration part 3.

  That is, the top electrode drive wiring 31 is electrically connected and fixed to the side surface of the first wiring pattern 21 shown in FIG. The

  Similarly, the lower electrode drive wiring 32 is fixed by electrically connecting, for example, solder or the like to the side surface of the second wiring pattern 22 shown in FIG. Is done.

  Further, the portion covered with the insulating outer skin 31 a of the upper electrode driving wiring 31 and the portion covered with the insulating outer skin 32 a of the lower electrode driving wiring 32 are fixed to the side surface of the housing 24.

  Then, the first wiring pattern 21, the upper electrode drive wiring 31 electrically connected to the side surface of the first wiring pattern 21, the second wiring pattern 22, and the side surface of the second wiring pattern 22 are electrically connected. A wiring protective material 33 that covers the connected lower electrode drive wiring 32 (or the side surface of the housing 24) with insulation is further formed of a non-conductive material.

  For example, the ultrasonic transducer 1 generally performs the following operation.

  A bias voltage is applied between the upper electrode 16 and the lower electrode 12 via the upper electrode drive wiring 31 and the lower electrode drive wiring 32, and the third insulating layer 15, the upper electrode 16, and the protective film 17 on the gap 14 are applied. Apply tension to the membrane.

  When a drive signal is supplied to the lower electrode 12 and the upper electrode 16 in this state, the membrane described above vibrates and ultrasonic waves are transmitted.

  Further, when an ultrasonic wave is received with a bias voltage applied between the lower electrode 12 and the upper electrode 16, the membrane vibrates and the distance between the lower electrode 12 and the upper electrode 16 changes, and the electrode changes. The voltage between them changes and is detected as an electrical signal.

  As the ultrasonic transducer 1, FIG. 2 shows a capacitive ultrasonic transducer (C-MUT) provided with a gap 14, but instead of this, a piezoelectric ultrasonic wave as shown in FIG. It may be a vibrator (P-MUT (Piezoelectric Micromachined Ultrasonic Transducer)). FIG. 3 is a cross-sectional view taken along the line AA of FIG. 1 when configured as a P-MUT.

  In the P-MUT shown in FIG. 3, a piezoelectric element 14p (this piezoelectric element 14p is also called a piezoelectric element) is arranged instead of the gap 14 in the C-MUT shown in FIG.

  A wiring structure similar to that of the above-described P-MUT can be adopted for such a C-MUT.

  According to the first embodiment, the wiring patterns 21 and 22 are directly provided on both side surfaces of the substrate 10 to connect the upper electrode 16 and the lower electrode 12, respectively. Since the upper electrode drive wiring 31 and the lower electrode drive wiring 32 are connected to each other, it is not necessary to perform wiring on the upper surface side of the substrate 10. As a result, since the wiring does not protrude above the protective film 17, it is possible to ensure contact with the subject and transmit / receive ultrasonic waves to / from the subject with high efficiency.

  Further, since the backing material 23 is disposed on the lower surface side of the substrate 10 corresponding to the region where the gap 14 (or the piezoelectric element 14p) is provided, unnecessary vibration can be sufficiently absorbed. Furthermore, since the housing 24 is also provided so as to surround the outer periphery of the backing material 23, the shape of the backing material 23 is stabilized. Thus, the original resolution of the ultrasonic transducer 1 can be ensured without impairing the acoustic characteristics.

For example, when connecting to the housing part 2 after wiring to the ultrasonic vibration part 3, it is necessary to work without impairing the wiring connection to the ultrasonic vibration part 3, so that the connection work is extremely difficult. It is. On the other hand, when the ultrasonic vibration part 3 is connected after fixing the wiring to the housing part 2, the wiring connection part such as a flexible printed board is finely bent at the end of the housing part 2 facing the board 10. In addition, it is necessary to fix the electrode surface so as to be conductive, and similarly difficult work is required. On the other hand, according to the present embodiment, wiring can be performed on the ultrasonic transducer 1 in which the ultrasonic vibration unit 3 and the housing unit 2 are connected, and thus there is an advantage that the assemblability is improved.
[Embodiment 2]

  4 to 6 show Embodiment 2 of the present invention. FIG. 4 is a cross-sectional view showing a state in which a C-MUT is configured on a substrate with through-hole vias, and FIG. 5 is a configuration of the C-MUT. FIG. 6 is a cross-sectional view showing a state in which a cut substrate is cut at a through-hole via portion, and FIG. 6 is a cross-sectional view showing a state in which wiring is performed on the substrate cut at the through-hole via portion.

  In the second embodiment, parts that are the same as those in the first embodiment are given the same reference numerals and description thereof is omitted, and only differences are mainly described.

  In the present embodiment, the C-MUT is described as an example, but it may be a P-MUT as in the first embodiment.

  In the present embodiment, as the substrate 10, as shown in FIG. 4, a substrate 10 having through-hole vias 41, 42, 43 provided at appropriate intervals is used. Here, each of the through-hole vias 41, 42, and 43 is a via provided so as to penetrate in the thickness direction of the substrate 10 (that is, a via exposed at least on the upper surface of the substrate 10). In the cross-sectional view of FIG. 4, the through hole via 41 is provided on the left side of the substrate 10, the through hole via 42 is provided on the right side, and two are provided in the center. Is a through-hole via 43. Among the through-hole vias 41, 42, and 43, the through-hole via 43 is provided at a position corresponding to a region where the air gap 14 (or the piezoelectric element 14p) is provided. (Or the piezoelectric element 14p) is provided at a position corresponding to a region where the piezoelectric element 14p is not provided.

  The first insulating layer 11 to the protective film 17 are sequentially laminated on the upper surface of the substrate 10 to form the vibrator portion, as in the first embodiment. However, the upper electrode 16 and the lower electrode 12 are formed so as to be electrically connected to the through-hole via 41 and the through-hole via 42, respectively.

  As shown in FIG. 4, the substrate 10 on which the vibrator portion is formed is then cut in the thickness direction of the substrate 10 so that the through-hole via 41 and the through-hole via 42 are exposed. The exposed through hole via 41 becomes the first conductive portion, and the through hole via 42 becomes the second conductive portion.

  However, since it is difficult to cut only the substrate 10 without cutting the through-hole vias 41 and 42, the through-hole vias 41 and 42 are practically included at the position indicated by the arrow B in FIG. The substrate 10 is cut.

  Subsequently, as shown in FIG. 6, after attaching the backing material 23 and the housing 24 to the substrate 10, the upper electrode drive wiring 31 is electrically connected to the cut surface of the through-hole via 41 that is the first conductive portion. The lower electrode drive wiring 32 is fixed and electrically connected to the cut surface of the through-hole via 42 that is the second conductive portion.

  Thereafter, the wiring connection portion is covered with the wiring protective material 33 as in the first embodiment.

According to the second embodiment, the through-hole via disposed at a position corresponding to the region where the air gap 14 (or the piezoelectric element 14p) is not provided, using the substrate 10 provided with the through-hole via. By using 41 and 42 as the first conductive portion and the second conductive portion, it is possible to achieve substantially the same effect as in the first embodiment.
[Embodiment 3]

  FIGS. 7 to 9 show Embodiment 3 of the present invention, FIG. 7 is a cross-sectional view showing a state in which a C-MUT is configured on a substrate with blind vias, and FIG. 8 is a configuration of the C-MUT. FIG. 9 is a cross-sectional view showing a state in which the substrate is cut at the blind via portion, and FIG. 9 is a cross-sectional view showing a state in which wiring is performed on the substrate cut at the blind via portion.

  In the third embodiment, parts that are the same as those in the first and second embodiments are given the same reference numerals, description thereof is omitted, and only differences are mainly described.

  In the present embodiment, the C-MUT will be described as an example, but the P-MUT may be used as in the first and second embodiments.

  In the second embodiment described above, the first conductive portion and the second conductive portion are formed using the through-hole via. However, in this embodiment, the first conductive portion and the second conductive portion are formed using the blind via. It is supposed to be.

  That is, the substrate 10 of this embodiment is formed by stacking the first substrate 10A on the upper side and the second substrate 10B on the lower side.

  Vias 41A and 42A are provided in the first substrate 10A, but no vias are provided in the second substrate 10B. Accordingly, the vias 41A and 42A are blind vias when viewed from the entire substrate 10 (the entire first substrate 10A and the second substrate 10B), and the upper surface of the substrate 10 (on the side where the vibrator portion is formed). Surface) but not on the lower surface (surface on the housing 24 side).

  The first insulating layer 11 to the protective film 17 are sequentially laminated on the upper surface of the substrate 10 (that is, the upper surface of the first substrate 10A) to form the vibrator portion, as in the first and second embodiments. It is. However, the upper electrode 16 is electrically connected to the blind via 41A, and the lower electrode 12 is electrically connected to the blind via 42A.

  The blind vias 41A and 42A are provided at positions corresponding to regions where the air gap 14 (or the piezoelectric element 14p) is not provided, similar to the through-hole vias 41 and 42 of the second embodiment.

  Then, more practically, the blind via 41A at the position indicated by the arrow C in FIG. 8 is exposed so that the substrate 10 on which the vibrator portion is formed as shown in FIG. 7 exposes the blind via 41A and the blind via 42A. , 42A are cut in the thickness direction. The exposed blind via 41A becomes the first conductive portion, and the blind via 42A becomes the second conductive portion.

  Subsequently, as shown in FIG. 9, after attaching the backing material 23 and the housing 24 to the substrate 10, the upper electrode drive wiring 31 is electrically connected and fixed to the cut surface of the blind via 41 </ b> A that is the first conductive portion. Then, the lower electrode drive wiring 32 is electrically connected and fixed to the cut surface of the blind via 42A which is the second conductive portion.

  Thereafter, the wiring connection portion is covered with the wiring protection member 33 as in the first and second embodiments.

  According to the third embodiment, the same effect as that of the second embodiment using the substrate 10 provided with the through-hole vias 41 and 42 can be obtained by using the substrate 10 provided with the blind vias 41A and 42A. Can be played.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Moreover, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, you may delete some components from all the components shown by embodiment. Furthermore, the constituent elements over different embodiments may be appropriately combined. Thus, it goes without saying that various modifications and applications are possible without departing from the spirit of the invention.

DESCRIPTION OF SYMBOLS 1 ... Ultrasonic transducer 2 ... Housing part 3 ... Ultrasonic vibration part 3a ... MUT element 3b ... MUT cell 10 ... Board | substrate 10A ... 1st board | substrate 10B ... 2nd board | substrate 11 ... 1st insulating layer (vibrator part)
12 ... Lower electrode (vibrator)
13 ... 2nd insulating layer (vibrator part)
14 ... Gap (vibrator)
14p ... Piezoelectric element (vibrator)
15 ... 3rd insulating layer (vibrator part)
16 ... Upper electrode (vibrator)
17 ... Protective film (vibrator)
21: Wiring pattern (first conductive part)
22 ... Wiring pattern (second conductive part)
DESCRIPTION OF SYMBOLS 23 ... Backing material 24 ... Housing 31 ... Upper electrode drive wiring 31a ... Insulation outer skin 32 ... Lower electrode drive wiring 32a ... Insulation outer skin 33 ... Wiring protection material 41 ... Through-hole via (1st electroconductive part)
42. Through-hole via (second conductive part)
43 ... through-hole via 41A ... blind via (first conductive part)
42A ... Blind via (second conductive part)

Claims (6)

A substrate,
A vibrator unit that is disposed on one surface of the substrate, and includes a lower electrode, a gap or a piezoelectric element, and an upper electrode facing the lower electrode across the gap or the piezoelectric element;
A backing material disposed on the other side of the substrate;
A housing that is disposed on the other surface of the substrate so as to surround an outer periphery of the backing material, and holds the backing material;
A first conductive part disposed on one side of the substrate and electrically connected to the upper electrode;
A second conductive part disposed on the other side of the substrate and electrically connected to the lower electrode;
An upper electrode driving wiring electrically connected to a side surface of the first conductive portion;
A lower electrode driving wiring electrically connected to a side surface of the second conductive portion;
An ultrasonic transducer comprising:   The ultrasonic transducer according to claim 1, wherein the first conductive portion and the second conductive portion are vias provided in the substrate so as to be exposed at least on the one surface of the substrate.   The ultrasonic transducer according to claim 2, wherein the via is a through-hole via that penetrates the substrate or a blind via that is exposed on the one surface of the substrate and not exposed on the other surface. .   The said 1st electroconductive part and the said 2nd electroconductive part are the said board | substrate cut | disconnected and formed in the thickness direction of this board | substrate so that the said via | veer may be exposed. Ultrasonic transducer. The first conductive portion and the second conductive portion are formed by cutting the substrate in the thickness direction of the substrate so as to include the via,
The ultrasonic transducer according to claim 4, wherein the upper electrode drive wiring and the lower electrode drive wiring are connected to a cut surface of the via.   The first conductive portion, the upper electrode drive wiring electrically connected to the side surface of the first conductive portion, the second conductive portion, and the lower electrode electrically connected to the side surface of the second conductive portion The ultrasonic transducer according to claim 1, further comprising a wiring protective material that covers the drive wiring with an insulating property.

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