JP2010014618A - Angular-velocity sensor and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an angular-velocity sensor and its manufacturing method for reducing inferiority of wire bonding, while properly holding the piezoelectric effect of a piezoelectric film, in particular. <P>SOLUTION: The angular-velocity sensor for using the piezoelectric effect of the piezoelectric film 29 to detect angular-velocity includes a vibrator 12, formed in the order of a lower electrode 28, the piezoelectric film 29 and an upper electrode 31, from downward above a substrate 27. The lower electrode 28 is formed of Pt or Pt alloy, a part of the lower electrode 28 is an electrode pad 32 exposed from the piezoelectric film 29, without the piezoelectric film 29 being formed thereon, and is wire-bonded via a conductive connection intermediate layer 35, formed thinner than the piezoelectric film 29 on the electrode pad 32. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  In particular, the present invention relates to an angular velocity sensor capable of reducing wire bonding defects while maintaining a good piezoelectric effect of a piezoelectric film, and a manufacturing method thereof.

  Patent Document 1 listed below discloses an invention relating to an angular velocity sensor (vibration gyro sensor). The angular velocity sensor includes, for example, a tuning fork vibrator, and a drive unit and a detection unit formed in this order from the bottom to the bottom electrode, the piezoelectric film, and the top electrode are formed on the two arm portions. Further, the lower electrode and the upper electrode are configured to have a wiring pattern and an electrode pad connected to the base of the wiring pattern, and wire bonding is performed on the electrode pad (refer to [0007 of Patent Document 1). ] Column).

  FIG. 18 is a partial cross-sectional view of a conventional angular velocity sensor. As shown in FIG. 18, the lower electrode 2, the piezoelectric film 3, and the upper electrode 4 are formed in this order on the Si substrate 1 from the bottom. As shown in FIG. 18, a hole portion 6 is formed in the base portion 5 a of the arm portion 5 constituting the vibrator, and an electrode pad 7 that is a part of the lower electrode 2 is exposed from the hole portion 6. Then, wire bonding is performed on the electrode pad 7.

  By the way, the lower electrode 2 also functions as an underlayer for obtaining good piezoelectric characteristics of the piezoelectric film 3. For the lower electrode 2, Pt is preferably used because the crystal orientation of the piezoelectric film 3 is adjusted and heat resistance is required.

  However, on the electrode pad 7 made of Pt, proper wire bonding cannot be performed and contact failure is likely to occur. This is considered due to the fact that the film quality of Pt is very hard.

It was also necessary to obtain a good connection structure between the lower electrode 2 and the wire without hindering the piezoelectric effect.
JP 2008-122261 A

  Accordingly, the present invention is to solve the above-described conventional problems, and in particular, to provide an angular velocity sensor and a method for manufacturing the same that can reduce defects in wire bonding while maintaining a good piezoelectric effect of the piezoelectric film. Yes.

The present invention provides an angular velocity sensor that has a vibrator formed in the order of a lower electrode, a piezoelectric film, and an upper electrode from the bottom on a substrate, and detects an angular velocity using the piezoelectric effect of the piezoelectric film.
The lower electrode is made of Pt or a Pt alloy,
A part of the lower electrode is an electrode pad exposed from the piezoelectric film without forming the piezoelectric film thereon,
Wire bonding is performed on the electrode pad through a conductive connection intermediate layer formed thinner than the piezoelectric film.

  Thereby, the defect of wire bonding can be reduced effectively, maintaining the piezoelectric effect of a piezoelectric film favorable.

  In the present invention, it is preferable that a hole is formed in the piezoelectric film, and the electrode pad is exposed from the hole. At this time, it is preferable that the connection intermediate layer is formed only in the hole. Thereby, the influence on the piezoelectric effect by providing a connection intermediate | middle layer can be made smaller.

  In the present invention, the connection intermediate layer is preferably formed of at least one of Au, Al, and AlCu. As a result, it is possible to improve the adhesion with the electrode pad formed of Pt or Pt alloy, and it is possible to appropriately perform wire bonding on the upper surface of the connection intermediate layer.

The present invention has a vibrator formed on a substrate in the order of a lower electrode, a piezoelectric film, and an upper electrode from the bottom, and a method for manufacturing an angular velocity sensor that detects an angular velocity using the piezoelectric effect of the piezoelectric film.
Forming the vibrator by forming the lower electrode from Pt or a Pt alloy and further exposing a part of the lower electrode as an electrode pad from the piezoelectric film;
Forming a conductive connection intermediate layer on the electrode pad, wherein the connection intermediate layer is formed thinner than the piezoelectric film;
Applying wire bonding to the upper surface of the connection intermediate layer;
It is characterized by having. Thereby, it is possible to easily and appropriately manufacture an angular velocity sensor that can effectively reduce defects in wire bonding while maintaining a good piezoelectric effect.

  In this invention, it is preferable to provide the process of forming a hole part in the said piezoelectric film and exposing the said electrode pad from the said hole part. At this time, it is preferable that the connection intermediate layer is formed only in the hole.

  In the present invention, it is preferable that the connection intermediate layer is formed of at least one of Au, Al, and AlCu. As a result, it is possible to improve the adhesion with the electrode pad formed of Pt or Pt alloy, and it is possible to appropriately perform wire bonding on the upper surface of the connection intermediate layer.

  In the present invention, it is possible to effectively reduce defects in wire bonding while maintaining a good piezoelectric effect.

  FIG. 1A is a plan view of an angular velocity sensor (vibrating gyro sensor) according to the present embodiment, and FIG. 1B is an angular velocity as viewed from the direction of the arrow cut along the line AA in FIG. 2 is a partially enlarged sectional view showing a connection structure between a wire and an electrode pad, and FIG. 3 is a partial sectional view showing another connection structure.

  The X-axis direction and the Y-axis direction in each figure indicate two orthogonal directions in the substrate plane. The Z-axis direction indicates a height direction (vertical direction) orthogonal to the X-axis direction and the Y-axis direction.

  As shown in FIG. 1, the angular velocity sensor (vibration gyro sensor) 10 includes a vibrator 12. The angular velocity sensor 10 is mounted via a pedestal portion 13 on a mounting substrate 11 provided with an integrated circuit or the like.

  The vibrator 12 includes a Si substrate 27 and a piezoelectric functional element 14 for detecting a displacement amount when the vibrator 12 receives a Coriolis force.

  In the form shown in FIG. 1, the vibrator 12 is a tuning fork vibrator. As shown in FIG. 1A, the vibrator 12 has two arm portions 15 and 16 (a first arm portion 15 and a second arm portion 16) that extend long in the Y-axis direction with a predetermined interval in the X-axis direction. And a base portion (connecting portion) 17 that connects one end portions of the arm portions 15 and 16.

  As shown in FIG. 1B, the base portion 17 of the vibrator 12 is bonded and fixed on the mounting substrate 11 via the pedestal portion 13. Therefore, as shown in FIG. 1B, the arm portions 15 and 16 of the vibrator 12 are in a state of floating upward from the upper surface of the mounting substrate 11.

  The piezoelectric functional element 14 is formed on the upper surface of the Si substrate 27 extending from the arm portions 15 and 16 to the base portion 17. Hereinafter, the form of the piezoelectric functional element 14 will be described.

  As shown in FIGS. 1 and 2, a first drive unit 18 and a second drive unit 19 which are provided on the Si substrate 27 constituting the first arm unit 15 so as to be separated from each other in the X-axis direction, and the drive unit A detection unit 20 provided between 18 and 19 is provided.

  As shown in FIG. 1B, the first driving unit 18 and the second driving unit 19 are composed of a lower electrode 28 from the bottom, for example, a piezoelectric film 29 made of PZT and polarized in the vertical direction (Z-axis direction), and The upper electrode (drive electrode) 31 is laminated in this order.

  The detection unit 20 is also laminated in order of a lower electrode 28 from the bottom, for example, a piezoelectric film 29 made of PZT and polarized in the vertical direction (Z-axis direction), and an upper electrode (detection electrode) 31.

  The detection unit 20 is provided along the Y-axis direction at a substantially central position in the X-axis direction (width direction) of the arm unit 15, and each drive unit 18, 19 is moved from the detection unit 20 in the X-axis direction (width direction). ) At substantially equal intervals along the Y-axis direction.

  As shown in FIG. 1A, the same piezoelectric functional element 14 as the first arm portion 15 is also formed on the second arm portion 16 side. The piezoelectric functional element 14 formed on the first arm portion 15 and the piezoelectric functional element 14 formed on the second arm portion 16 are in the Y-axis direction between the first arm portion 15 and the second arm portion 16. It is formed in a line symmetrical relationship with the center line as the axis of symmetry.

  The lower electrode 28 functions as a common ground, and a part of the lower electrode 28 is exposed as an electrode pad 32 from a hole 29a formed in the piezoelectric film 29 as shown in FIG.

  As shown in FIG. 1A, the upper electrode 31 of the first driving unit 18 formed on the first arm unit 15 and the upper electrode 31 of the first driving unit 18 formed on the second arm unit 16 are A wiring pattern and a common electrode pad 21 connected to both the wiring patterns and formed on the piezoelectric film 29 of the base portion 17 are configured.

  As shown in FIG. 1A, the upper electrode 31 of the second driving unit 19 formed on the first arm unit 15 and the upper electrode 31 of the second driving unit 19 formed on the second arm unit 16 are And a wiring pattern and a common electrode pad 22 connected to both wiring patterns and formed on the piezoelectric film 29 of the base portion 17.

  Further, as shown in FIG. 1A, the upper electrode 31 of the detection unit 20 formed on the first arm unit 15 and the upper electrode 31 of the detection unit 20 formed on the second arm unit 16 are connected to the wiring pattern. The electrode pads 23 and 24 are connected to each wiring pattern and formed on the piezoelectric film 29 of the base portion 17.

  Wire bonding is performed on each electrode pad 21, 22, 23, 24, 32 and is electrically connected to an integrated circuit (IC) (not shown). Driving vibrations whose phases are opposite to each other are supplied to the electrode pads 21 and 22 from the integrated circuit. At this time, for example, when the piezoelectric film 29 of the first drive unit 18 contracts in the Y-axis direction due to the piezoelectric effect, the piezoelectric film 29 of the second drive unit 19 extends in the Y-axis direction. As a result, the arm portions 15 and 16 are bent in the X-axis direction in the opposite phase to cause tuning fork vibration.

  Thus, when the vibrator 12 is tuning fork oscillated in the X-axis direction, when the angular velocity Ω around the Y-axis is applied to the angular velocity sensor 10, the arm portions 15 and 16 are reversed in the Z-axis direction by Coriolis force. Displace with phase. The displacement amount of each arm part 15 and 16 at this time is detected by the upper electrode 31 of the detection part 20 provided in each arm part 15 and 16. The charges detected by the upper electrodes 31 of the arm portions 15 and 16 have opposite polarities, and these charges are guided to the electrode pads 23 and 24, respectively. Then, signal processing is performed by an integrated circuit electrically connected to the electrode pads 23 and 24 through wire bonding, and an angular velocity signal is output.

  As shown in FIGS. 1A and 1B, a conductive connection intermediate layer 35 is formed on the electrode pad 32 on the lower electrode side. As shown in an enlarged view in FIG. 2, the thickness H1 of the connection intermediate layer 35 is smaller than the thickness H2 of the piezoelectric film 29. Therefore, the upper surface 35 a of the connection intermediate layer 35 is located lower than the upper surface 29 b of the piezoelectric film 29 and the upper surface 31 a of the upper electrode 31. In addition, the film thickness H1 of the connection intermediate layer 35 is, for example, in the range of 0.3 to 1.3 μm, and the film thickness H2 of the piezoelectric film 29 is in the range of 2.5 to 3.5 μm.

  Then, as shown in FIGS. 1B and 2, wire bonding is performed on the upper surface 35 a of the connection intermediate layer 35.

  The lower electrode 28 and the electrode pad 32 formed integrally with the lower electrode 28 are made of Pt or a Pt alloy (Pt—Ti or the like). Thereby, good piezoelectric characteristics of the piezoelectric film 29 formed of PZT (lead zirconate titanate) can be obtained.

  The wire 36 by wire bonding is formed of a material having good electrical conductivity. The wire 36 is preferably made of Au. The joint portion (tip portion) 36a of the wire 36 has a shape collapsed by being originally pressed into a ball shape by a capillary, and at the time of wire bonding, heat and ultrasonic waves are applied to the wire 36. The joining portion 36 a is joined to the upper surface 35 a of the connection intermediate layer 35.

  Therefore, the connection intermediate layer 35 needs to have heat resistance, but unlike the lower electrode 28, the connection intermediate layer 35 is not a base layer of the piezoelectric film 29, so that the degree of freedom in material selection is increased. It is also possible to form the same material.

  In the present embodiment, the connection intermediate layer 35 is formed of at least one of Au, Al, and AlCu. These materials are softer than Pt. The connection intermediate layer 35 can be formed using an existing method such as a sputtering method or a plating method.

  In the present embodiment, wire bonding is not performed directly on the electrode pad 32 formed of Pt or a Pt alloy, but via the connection intermediate layer 35 formed of Au or the like. Thereby, since a favorable chemical bond is generated between the upper surface 35a of the connection intermediate layer 35 and the bonding portion 36a of the wire 36, it is possible to reduce wire bonding defects such as the wire 36 being easily peeled off.

  In the present embodiment, as shown in FIG. 2, the thickness H1 of the connection intermediate layer 35 is made thinner than the thickness H2 of the piezoelectric film 29. In the form shown in FIG. 2, the connection intermediate layer 35 is formed only in the hole 29 a formed in the piezoelectric film 29. As shown in FIG. 2, the width T1 of the connection intermediate layer 35 is smaller than the minimum width T2 of the hole 29a, and the connection intermediate layer 35 is not in contact with any part of the piezoelectric film 29 (the connection intermediate layer 35 is piezoelectric). Away from the side of the membrane 29). Therefore, the connection intermediate layer 35 does not affect the piezoelectric effect of the piezoelectric film 29.

  On the other hand, in the embodiment shown in FIG. 3 (a cross-sectional view different from FIG. 2), the connection intermediate layer 35 is formed on the electrode film 32 exposed from the hole 29 a formed in the piezoelectric film 29. And the upper surface of the protective layer (insulating layer) 37 formed above the piezoelectric film 29. In the form shown in FIG. 3 as well, the thickness H1 of the connection intermediate layer 35 is smaller than the thickness H2 of the piezoelectric film 29 as in FIG.

  In the embodiment shown in FIG. 3, the connection intermediate layer 35 is formed not only in the hole 29a but also from the side surface 29c of the piezoelectric film 29 to the upper position. Therefore, although there is a possibility that the piezoelectric effect of the piezoelectric film 29 is somewhat affected as compared with the embodiment shown in FIG. 2, the influence is considered to be very small because the thickness H1 of the connection intermediate layer 35 is small. It is done. For example, in the embodiment (comparative example) in which the connection intermediate layer 35 is formed up to the dotted line position shown in FIG. 3 or the same position as the upper electrode 31 (comparative example), the thickness of the connection intermediate layer 35 is equal to or greater than the film thickness H2 of the piezoelectric film 29. Therefore, the process of forming the connection intermediate layer 35 is complicated, and the piezoelectric effect of the piezoelectric film 29 is easily inhibited. In the embodiment of FIG. 3, since the thickness H1 of the connection intermediate layer 35 is formed thinner than that of the comparative example, the formation process of the connection intermediate layer 35 can be facilitated and the piezoelectric effect of the piezoelectric film 29 can be kept good. I can do it.

  As described above, according to this embodiment, it is possible to effectively reduce defects in wire bonding while keeping the piezoelectric effect of the piezoelectric film 29 good.

  As shown in FIG. 1, the hole 29 a is not formed in the piezoelectric film 29, and the lower electrode 28 is formed so as to extend to the rear position of the base portion 17 to expose the electrode pad 32 from the rear position of the base portion 17. However, since the portion of the base portion 17 becomes large in such a form and the size reduction of the vibrator 12 cannot be promoted, a hole 29a is formed in the piezoelectric film 29, and the electrode pad 32 on the lower electrode side is exposed from the hole 29a. It is preferable to adopt a configuration in which the vibrator 12 can be miniaturized.

  In the above embodiment, the tuning fork type vibrator is used, but a tuning piece type vibrator or the like may be used. Further, the connection intermediate layer 35 may be provided on the electrode pads 32 on the upper electrode side as well as on the electrode pads 32 on the lower electrode side.

  4 to 17 are process diagrams showing a method of manufacturing the angular velocity sensor (vibration gyro sensor) of this embodiment. (A) of each figure shows sectional drawing, (b) of each figure shows a top view. However, FIGS. 12, 13, and 14 are enlarged cross-sectional views taken along the line CC shown in FIG. 11B.

In the step shown in FIG. 4, an insulating layer 39 made of SiO ₂ or the like is formed on the upper surface 38 a of the SOI substrate 38. The SOI substrate 38 has a stacked structure of Si substrates 27 and 40 and an oxide insulating layer (sacrificial layer, BOX layer) 41 formed of, for example, SiO ₂ between the Si substrates 27 and 40. The Si substrate 27 located on the upper surface side of the SOI substrate 38 is also called an active layer and has a film thickness of about 150 to 200 μm. The oxide insulating layer 41 has a thickness of about 0.5 μm. The total film thickness of the SOI substrate 38 is around 500 μm. The formation of the insulating layer 39 is optional.

  Next, in the step shown in FIG. 5, the lower electrode 28, the piezoelectric film 29, and the upper electrode 31 are stacked in this order on the insulating layer 39 from the bottom. The piezoelectric film 29 is polarized in the vertical direction (Z-axis direction).

  Here, the lower electrode 28 is formed of Pt or a Pt alloy (Ti-Pt or the like). In addition, the piezoelectric film 29 is formed of PZT. In addition to PZT, the piezoelectric film 29 can be formed of lead titanate (PT), lead zirconate (PZ), lanthanum (La) -added lead zirconate titanate (PLZT), or the like. The upper electrode 31 is formed of at least one of Au, Al, and AlCu.

  Next, in the step shown in FIG. 6, the upper electrode 31 is formed into various electrode pads and wiring patterns connected to the electrode pads as shown in FIG. 6B. In the process of FIG. 6, the unnecessary upper electrode 31 is removed by ion milling, RIE, or the like, but as shown in FIG. 6A, a part of the piezoelectric film 29 located under the removed upper electrode 31 is also removed. Dents.

  Next, in the step shown in FIG. 7, the unnecessary piezoelectric film 29 is removed by ion milling, RIE or the like, and the piezoelectric film 29 is left in a desired shape. At this time, as shown in FIG. 7A, the lower electrode 28 and the insulating layer 39 located under the unnecessary piezoelectric film 29 are also removed to expose the Si substrate 27.

  Next, in the step shown in FIG. 8, a hole 29a is formed in the piezoelectric film 29, and a part of the lower electrode 28 is exposed as an electrode pad 32 from the hole 29a.

Next, in a step shown in FIG. 9, a protective layer (insulating layer) 37 is formed on the entire surface with SiO ₂ or the like. The protective layer (insulating layer) 37 can be formed arbitrarily.

  Next, in the process shown in FIG. 10, the protective layer 37 on each electrode pad is removed by ion milling, RIE, or the like to expose each electrode pad from the protective layer 37.

Next, in a step shown in FIG. 11, a conductive connection intermediate layer 35 is formed on each electrode pad.
FIG. 12 is an enlarged cross-sectional view of FIG. As shown in FIG. 12, the thickness H 1 of the connection intermediate layer 35 formed on the electrode pad 32 on the lower electrode side is made thinner than the thickness H 2 of the piezoelectric film 29, and the connection intermediate layer 35 is formed on the piezoelectric film 29. It is preferable to form only in the formed hole 29a.

  The connection intermediate layer 35 is preferably formed of at least one of Au, Al, and AlCu.

  Here, in FIG. 12, the connection intermediate layer 35 is also formed on the electrode pads 21 to 24 on the upper electrode side, but it may not be formed. However, in particular, when the protective layer 37 is formed, the upper surfaces of the electrode pads 21 to 24 are lower than the upper surface of the protective layer 37. Therefore, in order to facilitate wire bonding, the electrode pads 21 to 21 on the upper electrode side are arranged. It is preferable to provide the connection intermediate layer 35 also on 24.

  In FIG. 12, the connection intermediate layer 35 is formed only on the electrode pad so as not to contact the protective layer 37, but the end portion 35 b of the connection intermediate layer 35 is extended to the upper surface of the protective layer 37 as shown in FIG. 13. Also good. Further, the end portion of the connection intermediate layer 35 formed on the electrode pad 32 on the lower electrode side may be formed to extend up to a position above the piezoelectric film 29 as shown in FIG. FIG. 14 shows a case where the protective film 37 is not formed.

  Next, in the step shown in FIG. 15 (the protective layer 37 is not shown in FIG. 15B. The same applies to FIGS. 16B and 17B), deep RIE (Deep RIE) is used. The Si substrate 27 is processed into the shape of the vibrator 12.

  Next, in the step shown in FIG. 16, the thickness of the Si substrate 27 is adjusted by CMP, RIE, polishing, or the like. In the step shown in FIG. 16, the support substrate (Si substrate) 40 and the oxide insulating layer 41 are removed. For example, the support substrate 40 is left and a part of the oxide insulating layer 41 is shown in FIG. 1B. The support substrate 40 may be mounted on the mounting substrate, leaving it as 13.

  Next, in the step shown in FIG. Then, each vibrator 12 is mounted on the mounting substrate 11 via the pedestal portion 13, and the integrated circuit (IC) and the connection intermediate layer 35 formed on each electrode pad are electrically connected by wire bonding.

  In this embodiment, as shown in FIG. 8, a hole 29a is formed in the piezoelectric film 29, and an electrode pad 32 formed of Pt or a Pt alloy which is a part of the lower electrode 28 is exposed from the hole 29a. 12, a conductive connection intermediate layer 35 is formed on at least the electrode pad 32 on the lower electrode side. At this time, the thickness H1 of the connection intermediate layer 35 is formed smaller than the thickness H2 of the piezoelectric film 29. Then, wire bonding is performed on the connection intermediate layer 35.

  According to the above, it is possible to easily and appropriately manufacture an angular velocity sensor that can effectively reduce wire bonding defects while maintaining a good piezoelectric effect.

FIG. 1A is a plan view of an angular velocity sensor (vibrating gyro sensor) according to the present embodiment, and FIG. 1B is an angular velocity as viewed from the direction of the arrow cut along the line AA in FIG. Sectional view of the sensor, Partial enlarged sectional view showing the connection structure between the wire and the electrode pad, Partial sectional view showing another connection structure, 1 process drawing ((a) is sectional drawing, (b) of each figure shows a top view) which shows the manufacturing method of the angular velocity sensor (vibration type gyro sensor) of this embodiment, FIG. 4 is a one-step process diagram ((a) is a sectional view, (b) in each figure is a plan view), FIG. 5 is a one-step process diagram ((a) is a cross-sectional view, and (b) of each figure is a plan view), FIG. 6 is a one-step process diagram ((a) is a sectional view, (b) in each figure is a plan view), FIG. 7 is a one-step process diagram ((a) is a cross-sectional view, (b) in each figure is a plan view), FIG. 8 is a one-step process diagram ((a) is a sectional view, and (b) in each figure is a plan view), FIG. 9 is a one-step process diagram ((a) is a sectional view, (b) in each figure is a plan view), FIG. 10 is a one-step process diagram ((a) is a cross-sectional view, (b) in each figure is a plan view), The partial expanded sectional view in CC line of Drawing 11 (b), FIG. 12 is a partially enlarged cross-sectional view having a configuration different from that of FIG. FIG. 12 is a partially enlarged cross-sectional view having a configuration different from that of FIG. FIG. 11 is a one-step process diagram ((a) is a cross-sectional view, and (b) of each figure is a plan view), FIG. 15 is a one-step process diagram ((a) is a sectional view, and (b) in each figure is a plan view), FIG. 16 is a process diagram (a is a cross-sectional view, and (b) is a plan view), Partial sectional view of a conventional angular velocity sensor (vibration gyro sensor),

Explanation of symbols

10 Angular velocity sensor (vibration gyro sensor)
DESCRIPTION OF SYMBOLS 11 Mounting substrate 12 Vibrator 13 Base part 14 Piezoelectric functional element 15, 16 Arm part 18, 19 Drive part 20 Detection part 21-24 Upper electrode side electrode pad 27 Si substrate 28 Lower electrode 29 Piezoelectric film 29a Hole part 31 Upper electrode 32 Lower electrode side electrode pad 35 Connection intermediate layer 36 Wire 38 SOI substrate

Claims (8)

In the angular velocity sensor that has a vibrator formed in order of a lower electrode, a piezoelectric film, and an upper electrode from the bottom on the substrate and detects an angular velocity using the piezoelectric effect of the piezoelectric film,
The lower electrode is made of Pt or a Pt alloy,
A part of the lower electrode is an electrode pad exposed from the piezoelectric film without forming the piezoelectric film thereon,
An angular velocity sensor characterized by being wire-bonded on the electrode pad via a conductive connection intermediate layer formed thinner than the piezoelectric film.   The angular velocity sensor according to claim 1, wherein a hole is formed in the piezoelectric film, and the electrode pad is exposed from the hole.   The angular velocity sensor according to claim 2, wherein the connection intermediate layer is formed only in the hole.   The angular velocity sensor according to claim 1, wherein the connection intermediate layer is formed of at least one of Au, Al, and AlCu. In a method of manufacturing an angular velocity sensor having a vibrator formed in order of a lower electrode, a piezoelectric film and an upper electrode from the bottom on a substrate and detecting an angular velocity using the piezoelectric effect of the piezoelectric film,
When forming the vibrator, forming the lower electrode from Pt or a Pt alloy, and further exposing a part of the lower electrode as an electrode pad from the piezoelectric film;
Forming a conductive connection intermediate layer on the electrode pad, wherein the connection intermediate layer is formed thinner than the piezoelectric film;
Applying wire bonding to the upper surface of the connection intermediate layer;
The manufacturing method of the angular velocity sensor characterized by having.   The method of manufacturing an angular velocity sensor according to claim 5, further comprising a step of forming a hole in the piezoelectric film and exposing the electrode pad from the hole.   The method of manufacturing an angular velocity sensor according to claim 6, wherein the connection intermediate layer is formed only in the hole.   The method for manufacturing an angular velocity sensor according to claim 5, wherein the connection intermediate layer is formed of at least one of Au, Al, and AlCu.

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