JP2017118625A - Piezoelectric drive device, manufacturing method for the same, motor, robot and pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a piezoelectric drive device capable of enhancing bonding strength among vibration units adjacent to one another.SOLUTION: A piezoelectric drive device includes a plurality of vibration units. Each of the plurality of vibration units includes: a diaphragm; a first electrode provided on the diaphragm; a piezoelectric layer provided on the first electrode; a second electrode provided on the piezoelectric layer; a contact hole provided at a position of the piezoelectric layer where the second electrode is not provided so as to pass through up to a top surface of the first electrode; and a wiring layer electrically connected to the first electrode or the second electrode via the contact hole. The plurality of the vibration units is disposed so as to overlap with one another in a thickness direction of the diaphragms in the piezoelectric drive device.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a piezoelectric drive device and a manufacturing method thereof, a motor, a robot, and a pump.

  Piezoelectric actuators (piezoelectric driving devices) that drive a driven body by vibrating a vibrating body by a piezoelectric element are used in various fields because they do not require a magnet or a coil. For example, the piezoelectric driving device disclosed in Patent Document 1 has a configuration in which four piezoelectric elements are arranged in two rows and two columns on each of two surfaces of a plate-like member, and a total of eight piezoelectric elements. It is the structure which produces a vibration. One end of the plate-like member is provided with a protrusion for rotating the rotor in contact with the rotor as the driven body. When an AC voltage is applied to two of the four piezoelectric elements arranged diagonally, the two piezoelectric elements expand and contract, and the protrusions reciprocate or elliptically move accordingly. And according to the reciprocating motion or elliptical motion of the protrusion of the reinforcing plate, the rotor as the driven body rotates in a predetermined rotational direction. In addition, the rotor can be rotated in the reverse direction by switching the two piezoelectric elements to which the AC voltage is applied to the other two piezoelectric elements.

  In addition, a piezoelectric driving device having a stack structure in which a piezoelectric driving body (piezoelectric vibrating body) is stacked in the thickness direction to increase the output is known (for example, Patent Document 2). The piezoelectric vibrating body of this piezoelectric drive device is supported by an elastic support.

JP 2004-320979 A Japanese Patent Laid-Open No. 08-237971

  For example, when a motor is constituted by a piezoelectric driving device to generate power, one of basic requirements is to increase driving force (output). As an example, in the apparatus disclosed in Patent Document 2 described above, an attempt is made to increase the output by using a stack structure.

  However, when stacking (stacking) vibration units in which piezoelectric elements are formed on the surface of the plate-like member, for example, adjacent vibration units are bonded using an adhesive or the like, but if the flatness of the vibration unit is poor, In some cases, the bonding area decreases between adjacent vibration units, and the bonding strength decreases.

  One of the objects according to some aspects of the present invention is to provide a piezoelectric driving device capable of increasing the bonding strength between adjacent vibration units. Another object of some aspects of the present invention is to provide a method of manufacturing a piezoelectric drive device that can increase the bonding strength between adjacent vibration units. Another object of some embodiments of the present invention is to provide a motor, a robot, or a pump including the piezoelectric driving device described above.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following aspects or application examples.

[Application Example 1]
One aspect of the piezoelectric drive device according to the present invention is:
A piezoelectric drive device including a plurality of vibration units,
The vibration unit is
A diaphragm,
A first electrode provided on the diaphragm;
A piezoelectric layer provided on the first electrode;
A second electrode provided on the piezoelectric layer;
A contact hole provided so as to penetrate to the upper surface of the first electrode at a position where the second electrode of the piezoelectric layer is not provided;
A wiring layer electrically connected to the first electrode or the second electrode through the contact hole;
Including
The plurality of vibration units are arranged so as to overlap in the thickness direction of the diaphragm.

  In such a piezoelectric drive device, the piezoelectric layer is provided other than directly below the second electrode. Therefore, in such a piezoelectric drive device, compared to a case where the piezoelectric layer is provided only directly below the second electrode, the bonding surface of the vibration unit (the surface bonded to another vibration unit of one vibration unit) ) Can be improved. Thereby, in such a piezoelectric drive device, the bonding area can be increased between the adjacent vibration units, and the bonding strength between the adjacent vibration units can be increased.

  In the description according to the present invention, the term “electrically connected” is used, for example, as another specific member (hereinafter “electrically connected” to “specific member (hereinafter referred to as“ A member ”)”. B member "))" and the like. In the description according to the present invention, in the case of this example, the case where the A member and the B member are in direct contact and electrically connected, and the A member and the B member are the other members. The term “electrically connected” is used as a case where the case where the terminals are electrically connected to each other is included.

[Application Example 2]
In application example 1,
The piezoelectric layer is
An active part sandwiched between the first electrode and the second electrode;
An inactive portion that is continuous with the active portion and is not sandwiched between the first electrode and the second electrode;
Have
The contact hole may be provided in the inactive portion.

  In such a piezoelectric driving device, the bonding strength between adjacent vibration units can be increased.

[Application Example 3]
In application example 1 or 2,
A protective layer provided to cover the upper and side surfaces of the second electrode, the upper surface of the piezoelectric layer, and the inner surface of the contact hole;
The protective layer may be an inorganic insulating layer.

  In such a piezoelectric drive device, it is possible to suppress moisture from adhering to the surface of the piezoelectric layer, and it is possible to suppress short circuit between the first electrode and the second electrode via moisture on the surface of the piezoelectric layer. can do.

[Application Example 4]
One aspect of a method for manufacturing a piezoelectric drive device according to the present invention is as follows.
A method of manufacturing a piezoelectric drive device including a plurality of vibration units,
Forming a first electrode on the diaphragm;
Forming a piezoelectric layer on the first electrode;
Forming a second electrode on the piezoelectric layer;
Forming a contact hole at a position where the second electrode of the piezoelectric layer is not formed so as to penetrate to the upper surface of the first electrode;
Forming a wiring layer electrically connected to the first electrode or the second electrode through the contact hole;
Forming a plurality of the vibration units,
The plurality of vibration units are arranged so as to overlap in the thickness direction of the diaphragm.

  In such a method for manufacturing a piezoelectric drive device, it is possible to manufacture a piezoelectric drive device that can increase the bonding strength between adjacent vibration units.

[Application Example 5]
In application example 4,
The piezoelectric layer is
An active part sandwiched between the first electrode and the second electrode;
An inactive portion that is continuous with the active portion and is not sandwiched between the first electrode and the second electrode;
Formed to have
The contact hole may be formed in the inactive portion.

  In such a method for manufacturing a piezoelectric drive device, it is possible to manufacture a piezoelectric drive device that can increase the bonding strength between adjacent vibration units.

[Application Example 6]
In application example 4 or 5,
Forming a protective layer so as to cover the upper and side surfaces of the second electrode, the upper surface of the piezoelectric layer, and the inner surface of the contact hole;
The material of the protective layer may be an inorganic insulating layer.

  In such a method of manufacturing a piezoelectric driving device, it is possible to suppress moisture from adhering to the surface of the piezoelectric layer, and the first electrode and the second electrode are short-circuited through the moisture on the surface of the piezoelectric layer. A piezoelectric drive device that can suppress this can be manufactured.

[Application Example 7]
One aspect of the motor according to the present invention is:
The piezoelectric drive device according to any one of Application Examples 1 to 3,
A rotor rotated by the piezoelectric drive device;
including.

  Such a motor can include a piezoelectric drive according to the present invention.

[Application Example 8]
One aspect of the robot according to the present invention is:
A plurality of link parts;
A joint part connecting a plurality of the link parts;
The piezoelectric drive device according to any one of Application Examples 1 to 3, wherein a plurality of the link portions are rotated by the joint portions;
including.

  Such a robot can include the piezoelectric driving device according to the present invention.

[Application Example 9]
One aspect of the pump according to the present invention is:
The piezoelectric drive device according to any one of Application Examples 1 to 3,
A tube that transports the liquid;
A plurality of fingers for closing the tube by driving the piezoelectric driving device;
including.

  Such a pump can include a piezoelectric drive according to the present invention.

The top view which shows typically the piezoelectric drive device which concerns on this embodiment. 1 is a cross-sectional view schematically showing a piezoelectric drive device according to an embodiment. The top view which shows typically the piezoelectric drive device which concerns on this embodiment. 1 is a cross-sectional view schematically showing a piezoelectric drive device according to an embodiment. 1 is a cross-sectional view schematically showing a piezoelectric drive device according to an embodiment. The top view which shows typically the piezoelectric drive device which concerns on this embodiment. The figure which shows the equivalent circuit for demonstrating the piezoelectric drive device which concerns on this embodiment. The figure for demonstrating operation | movement of the piezoelectric drive device which concerns on this embodiment. Sectional drawing for demonstrating the path | route length between the 1st electrode and 2nd electrode which pass along the surface of a piezoelectric material layer. Sectional drawing for demonstrating the path | route length between the 1st electrode and 2nd electrode which pass along the surface of a piezoelectric material layer. The flowchart for demonstrating the manufacturing method of the piezoelectric drive device which concerns on this embodiment. Sectional drawing which shows typically the manufacturing process of the piezoelectric drive device which concerns on this embodiment. Sectional drawing which shows typically the manufacturing process of the piezoelectric drive device which concerns on this embodiment. Sectional drawing which shows typically the manufacturing process of the piezoelectric drive device which concerns on this embodiment. Sectional drawing which shows typically the manufacturing process of the piezoelectric drive device which concerns on this embodiment. Sectional drawing which shows the sample used for the experiment example typically. Sectional drawing which shows the sample used for the experiment example typically. Sectional drawing which shows the sample used for the experiment example typically. Sectional drawing which shows the sample used for the experiment example typically. The table | surface which shows the relationship between pulse application time and destruction incidence. The graph which shows the relationship between pulse application time and destruction incidence. Sectional drawing which shows the sample used for the experiment example typically. Sectional drawing which shows the sample used for the experiment example typically. The metal micrograph after applying a voltage of 100V between the 1st electrode and the 2nd electrode. The metal micrograph after applying a voltage of 100V between the 1st electrode and the 2nd electrode. Sectional drawing which shows the sample used for the experiment example typically. Sectional drawing which shows the sample used for the experiment example typically. Sectional drawing which shows the sample used for the experiment example typically. Sectional drawing which shows the sample used for the experiment example typically. Sectional drawing which shows the sample used for the experiment example typically. The top view for demonstrating the test method of a tape peeling test. The table | surface which shows the number of peeled and the position of the interface where peeling occurred. The figure for demonstrating the robot which concerns on this embodiment. The figure for demonstrating the wrist part of the robot which concerns on this embodiment. The figure for demonstrating the pump which concerns on this embodiment.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. The embodiments described below do not unduly limit the contents of the present invention described in the claims. In addition, not all of the configurations described below are essential constituent requirements of the present invention.

1. Piezoelectric Drive Device First, a piezoelectric drive device according to the present embodiment will be described with reference to the drawings. FIG. 1 is a plan view schematically showing a piezoelectric driving device 100 according to this embodiment. 2 is a cross-sectional view taken along the line II-II of FIG. 1 schematically showing the piezoelectric driving device 100 according to the present embodiment.

  The piezoelectric drive device 100 includes a plurality of vibration units 102 as shown in FIGS. 1 and 2. In the illustrated example, the piezoelectric driving device 100 includes two vibration units 102a and 102b. Note that the number of the plurality of vibration units 102 is not particularly limited.

  As shown in FIG. 2, the first vibration unit 102 a and the second vibration unit 102 b include a substrate 10 and a structure body 101. The substrate 10 has a first surface 10a and a second surface 10b opposite to the first surface 10a. The structure 101 is provided on the first surface 10 a of the substrate 10. In FIG. 2, the structure 101 is illustrated in a simplified manner.

  The plurality of vibration units 102 are arranged so as to overlap in the thickness direction (of the vibration plate) of the substrate 10. The first vibration unit 102a and the second vibration unit 102b are joined so that the first surface 10a of the substrate 10 of the first vibration unit 102a and the first surface 10a of the substrate 10 of the second vibration unit 102b face each other. ing. In the illustrated example, the structure 101 has a joint surface 101a facing away from the second surface 10b, and the joint surface 101a of the first vibration unit 102a and the joint surface 101a of the second vibration unit 102b are adhesive 2 It is joined via.

  Although not shown, when the metal is exposed on the bonding surface 101a, the bonding surface 101a of the first vibration unit 102a and the bonding surface 101a of the second vibration unit 102b may be bonded by metal bonding. Good.

  Although not shown, the first vibration unit 102a and the second vibration unit 102b include the first surface 10a of the substrate 10 of the first vibration unit 102a and the second surface 10b of the substrate 10 of the second vibration unit 102b. May be joined so as to face each other. In this case, the structure 101 of the first vibration unit 102a and the substrate 10 of the second vibration unit 102b are joined.

Here, FIG. 3 is a plan view schematically showing the first vibration unit 102a. 4 is a cross-sectional view taken along line IV-IV of FIG. 3 schematically showing the first vibration unit 102a. FIG. 5 is a cross-sectional view taken along line VV in FIG. 3 schematically showing the first vibration unit 102a. The first vibration unit 102a and the second vibration unit 102b basically have the same configuration. Therefore, hereinafter, the first vibration unit 102a will be described with reference to FIGS. The description of the first vibration unit 102a can be basically applied to the second vibration unit 102b.

  As shown in FIGS. 3 to 5, the first vibration unit 102 a includes a substrate 10, a contact portion 20, and a structure 101. The structure 101 includes a first electrode 32, a piezoelectric layer 34, a second electrode 36, a first insulating layer (protective layer) 40, a second insulating layer 42, a third insulating layer 44, A first conductive layer 54 and a second conductive layer 56 constituting the wiring layer 50 and the second wiring layer 52 are included. For convenience, illustration of the insulating layers 40, 42, 44 and the conductive layers 54, 56 is omitted in FIG. In FIG. 5, the insulating layers 42 and 44 and the second conductive layer 56 are not shown.

  The substrate 10 includes, for example, a silicon substrate 11a and a base layer 11b provided on the silicon substrate 11a. The foundation layer 11b is an insulating layer. For example, the base layer 11b is composed of a laminate of a silicon oxide layer provided on the silicon substrate 11a and a zirconium oxide layer provided on the silicon oxide layer.

  In the present embodiment, “upper” does not have to be the direction side opposite to the direction of gravity, but is a specific direction side (for example, the first surface 10a side of the substrate 10). For example, “the member α is provided on the member β” means that “the member α is provided on one side (the first surface 10a side) of the member β”.

  As illustrated in FIG. 3, the substrate 10 includes a vibrating body portion (diaphragm) 12, a support portion 14, a first connection portion 16, and a second connection portion 18. The planar shape (the shape seen from the thickness direction of the substrate 10) of the vibrating body portion 12 is substantially rectangular. A structural body 101 is provided on the vibrating body portion 12. A piezoelectric element 30 including a piezoelectric layer 34 and electrodes 32 and 36 is provided on the vibrating body portion 12, and the vibrating body portion 12 can vibrate by deformation of the piezoelectric element 30. The support portion 14 supports the vibrating body portion 12 via the connection portions 16 and 18. In the illustrated example, the connection parts 16 and 18 extend from the center part in the longitudinal direction of the vibrating body part 12 in a direction orthogonal to the longitudinal direction and are connected to the support part 14.

The contact portion 20 is provided on the vibrating body portion 12. In the example shown in the drawing, the vibrating body 12 is provided with a recess 12a, and the contact portion 20 is fitted into the recess 12a and bonded (for example, bonded). The contact portion 20 is a member that contacts the driven member and transmits the movement of the vibrating body portion 12 to the driven member. The material of the contact portion 20 is, for example, ceramics (specifically, alumina (Al ₂ O ₃ ), zirconia (ZrO ₂ ), silicon nitride (Si ₃ N), etc.).

  The piezoelectric element 30 is provided on the substrate 10. Specifically, the piezoelectric element 30 is provided on the vibrating body portion 12.

  The first electrode 32 is provided on the vibrating body portion 12. In the illustrated example, the planar shape of the first electrode 32 is a rectangle. The first electrode 32 may be configured by an iridium layer provided on the vibrating body portion 12 and a platinum layer provided on the iridium layer. The thickness of the iridium layer is, for example, 1 nm to 100 nm, preferably 5 nm to 100 nm. The thickness of the platinum layer is, for example, not less than 50 nm and not more than 300 nm. The first electrode 32 is a metal layer made of Ti, Pt, Ta, Ir, Sr, In, Sn, Au, Al, Fe, Cr, Ni, Cu, or a mixture or stack of two or more of these. It may be a thing. The first electrode 32 is one electrode for applying a voltage to the piezoelectric layer 34.

The piezoelectric layer 34 is provided on the first electrode 32. In the illustrated example, the planar shape of the piezoelectric layer 34 is a rectangle. The thickness of the piezoelectric layer 34 is, for example, not less than 50 nm and not more than 20 μm, and preferably not less than 1 μm and not more than 7 μm. Thus, the piezoelectric element 30 is a thin film piezoelectric element. If the thickness of the piezoelectric layer 34 is smaller than 50 nm, the output of the piezoelectric driving device 100 may be small. Specifically, when the voltage applied to the piezoelectric layer 34 is increased in order to increase the output, the piezoelectric layer 34 may cause dielectric breakdown. If the thickness of the piezoelectric layer 34 is greater than 20 μm, cracks may occur in the piezoelectric layer 34 and the drive voltage may further increase.

  The piezoelectric layer 34 has an active part 34a and an inactive part 34b. The active portion 34 a of the piezoelectric layer 34 is a portion sandwiched between the first electrode 32 and the second electrode 36 of the piezoelectric layer 34. That is, the active portion 34a overlaps the electrodes 32 and 36 in plan view. The active part 34 a is actively driven when a voltage is applied between the electrodes 32 and 36.

  The inactive portion 34b of the piezoelectric layer 34 is continuous with the active portion 34a. The inactive portion 34 b is a portion that is not sandwiched between the first electrode 32 and the second electrode 36 of the piezoelectric layer 34. That is, the inactive portion 34b is a portion that does not overlap the electrodes 32 and 36 in plan view. The inactive portion 34b is a portion other than the active portion 34a of the piezoelectric layer 34.

  A first contact hole 60 penetrating to the upper surface 32 a of the first electrode 32 is provided in the inactive portion 34 b of the piezoelectric layer 34. That is, the first contact hole 60 is provided at a position where the second electrode of the piezoelectric layer 34 is not provided. Here, FIG. 6 is a plan view for explaining the position of the first contact hole 60. As shown in FIG. 6, a plurality of first contact holes 60 are provided around the second electrode 36 in plan view. Specifically, a plurality of first contact holes 60 are provided around each second electrode 36 of each of the piezoelectric elements 30a to 30e in plan view. For convenience, the first contact hole 60 is not shown in FIG.

  The outer edge of the piezoelectric layer 34 overlaps with the outer edge of the first electrode 32 in plan view, for example. In plan view, the piezoelectric layer 34 has an area smaller than the area of the first electrode 32, for example, by the amount excluding the area of the first contact hole 60. Although not shown, the support layer 14 and the connection portions 16 and 18 may also be provided with the piezoelectric layer 34.

As the piezoelectric layer 34, a perovskite oxide piezoelectric material is used. Specifically, the material of the piezoelectric layer 34 is, for example, lead zirconate titanate (Pb (Zr, Ti) O ₃ : PZT), lead zirconate titanate niobate (Pb (Zr, Ti, Nb) O). ₃ : PZTN). The piezoelectric layer 34 can be deformed (stretched) when a voltage is applied by the electrodes 32 and 36.

  The second electrode 36 is provided on the piezoelectric layer 34. In the illustrated example, the planar shape of the second electrode 36 is a rectangle. The second electrode 36 may be configured by an adhesion layer provided on the piezoelectric layer 34 and a conductive layer provided on the adhesion layer. The thickness of the adhesion layer is, for example, 10 nm or more and 100 nm or less. The adhesion layer is, for example, a TiW layer, a Ti layer, a Cr layer, a NiCr layer, a Ni layer, or a laminate thereof. The thickness of the conductive layer is, for example, 1 μm or more and 10 μm or less. The conductive layer is, for example, a Cu layer, an Au layer, an Al layer, or a laminate thereof. The second electrode 36 is the other electrode for applying a voltage to the piezoelectric layer 34.

As shown in FIG. 3, a plurality of piezoelectric elements 30 are provided. In the illustrated example, five piezoelectric elements 30 are provided (piezoelectric elements 30a, 30b, 30c, 30d, and 30e). In plan view (as viewed from the thickness direction of the substrate 10), for example, the areas of the piezoelectric elements 30a to 30d are the same, and the piezoelectric element 30e has a larger area than the piezoelectric elements 30a to 30d. The piezoelectric element 30 e is provided along the longitudinal direction of the vibrating body 12 at the central portion in the short direction of the vibrating body 12. The piezoelectric elements 30a, 30b, 30c, 30d
Are provided at the four corners.

  In the piezoelectric elements 30a to 30e, the first electrode 32 is provided as one continuous conductive layer. In the piezoelectric elements 30a to 30e, the piezoelectric layer 34 is provided as one continuous piezoelectric layer, and five active portions 34a of the piezoelectric layer 34 are provided corresponding to the piezoelectric elements 30a to 30e. Yes. In the piezoelectric elements 30a to 30e, five second electrodes 36 are provided corresponding to the piezoelectric elements 30a to 30e.

As shown in FIG. 4, the first insulating layer 40 is provided on the piezoelectric layer 34 and the electrodes 32 and 36. Specifically, the first insulating layer 40 is provided so as to cover the upper surface 36 a and the side surface 36 b of the second electrode 36, the upper surface 35 of the piezoelectric layer 34, and the inner surface 60 a of the first contact hole 60. The first insulating layer 40 is, for example, an inorganic insulating layer made of an inorganic material. Specifically, the material of the first insulating layer 40 is aluminum oxide (AlO _x ), tantalum oxide (TaO _x ), hafnium oxide (HfO _x ), or the like.

  The first insulating layer 40 is provided with second contact holes 62a and 62b. The second contact hole 62 a is provided in the first contact hole 60 so as to penetrate to the upper surface 32 a of the first electrode 32. The second contact hole 62 a is provided so as to penetrate to the upper surface 36 a of the second electrode 36.

  The first conductive layer 54 is provided on the first insulating layer 40. The first conductive layer 54 includes, for example, a titanium tungsten layer and a copper layer provided on the titanium tungsten layer. The first conductive layer 54 may further include a conductive adhesion layer provided between the titanium tungsten layer and the first insulating layer 40.

  The first conductive layer 54 constitutes a first wiring layer 50 and a second wiring layer 52. The first wiring layer 50 is electrically connected to the first electrode 32 through the first contact hole 60 and the second contact hole 62a. The second wiring layer 52 is electrically connected to the second electrode 36 through the second contact hole 62b.

  The second insulating layer 42 is provided on the first insulating layer 40 and the first conductive layer 54. For example, the second insulating layer 42 has photosensitivity. "Photosensitivity" refers to the property that a substance causes a chemical reaction by light. Specifically, the second insulating layer 42 can be patterned by exposure, development, and baking (heat treatment) without using etching. The second insulating layer 42 is, for example, an organic insulating layer. Specifically, the material of the second insulating layer 42 is an epoxy resin, an acrylic resin, or the like. A third contact hole 64 is provided in the second insulating layer 42. The third contact hole 64 is provided so as to penetrate to the upper surface 54 a of the first conductive layer 54.

  The second conductive layer 56 is provided on the second insulating layer 42 and the first conductive layer 54. The second conductive layer 56 is electrically connected to the first conductive layer 54 through the third contact hole 64. The material of the second conductive layer 56 is the same as that of the first conductive layer 54, for example. The second conductive layer 56 is electrically connected to a drive circuit 110 (see FIG. 7 described later) for driving the piezoelectric drive device 100. Thereby, the drive circuit 110 and the electrodes 32 and 36 can be electrically connected.

  The third insulating layer 44 is provided on the second insulating layer 42 and the second conductive layer 56. The material of the third insulating layer 44 is the same as the material of the second insulating layer 42, for example. The upper surface of the third insulating layer 44 constitutes, for example, a bonding surface 101a (see FIG. 2).

  FIG. 7 is a diagram showing an equivalent circuit for explaining the piezoelectric driving device 100. The piezoelectric elements 30 are divided into three groups. The first group has two piezoelectric elements 30a and 30d. The second group has two piezoelectric elements 30b and 30c. The third group has only one piezoelectric element 30e. As shown in FIG. 7, the first group of piezoelectric elements 30 a and 30 d are connected in parallel to each other and connected to the drive circuit 110. The second group of piezoelectric elements 30 b and 30 c are connected in parallel to each other and connected to the drive circuit 110. The third group of piezoelectric elements 30e are connected to the drive circuit 110 independently.

  The drive circuit 110 has a period between predetermined electrodes of the five piezoelectric elements 30a, 30b, 30c, 30d, and 30e, for example, the first electrode 32 and the second electrode 36 of the piezoelectric elements 30a, 30d, and 30e. An alternating voltage or a pulsating voltage that changes with time is applied. Thereby, the piezoelectric driving device 100 can rotate the rotor (driven member) in contact with the contact portion 20 in a predetermined rotation direction by ultrasonically vibrating the vibrating body portion 12. Here, the “pulsating voltage” means a voltage obtained by adding a DC offset to an AC voltage, and the direction of the voltage (electric field) of the pulsating voltage is one direction from one electrode to the other electrode.

  The direction of the electric field is preferably from the second electrode 36 to the first electrode 32 rather than from the first electrode 32 to the second electrode 36. Moreover, the rotor which contacts the contact part 20 can be rotated in a reverse direction by applying an alternating voltage or a pulsating current voltage between the electrodes 32 and 36 of the piezoelectric elements 30b, 30c and 30e.

  FIG. 8 is a diagram for explaining the operation of the vibrating body portion 12 of the piezoelectric driving device 100. As shown in FIG. 8, the contact portion 20 of the piezoelectric driving device 100 is in contact with the outer periphery of the rotor 4 as a driven member. The drive circuit 110 applies an alternating voltage or a pulsating voltage between the electrodes 32 and 36 of the piezoelectric elements 30a and 30d. Thereby, the piezoelectric elements 30a and 30d expand and contract in the direction of the arrow x. In response to this, the vibrating body portion 12 is bent and vibrated along the short direction of the vibrating body portion 12 in a state where no voltage is applied to the piezoelectric element 30 in the plane of the vibrating body portion 12. ) To deform into a meandering shape (S-shape). Furthermore, the drive circuit 110 applies an alternating voltage or a pulsating voltage between the electrodes 32 and 36 of the piezoelectric element 30e. Thereby, the piezoelectric element 30e expands and contracts in the direction of the arrow y. Thereby, the vibrating body portion 12 vibrates longitudinally in the plane of the vibrating body portion 12 (for example, longitudinal vibration along the longitudinal direction of the vibrating body portion 12 in a state where no voltage is applied to the piezoelectric element 30). Due to the bending vibration and longitudinal vibration of the vibrating body portion 12 as described above, the contact portion 20 moves elliptically as indicated by an arrow z. As a result, the rotor 4 rotates around the center 4a in a predetermined direction R (clockwise direction in the illustrated example).

  When the drive circuit 110 applies an AC voltage or a pulsating voltage between the electrodes 32 and 36 of the piezoelectric elements 30b, 30c, and 30e, the rotor 4 is in a direction opposite to the direction R (counterclockwise direction). Rotate to.

  Moreover, it is preferable that the resonance frequency of the bending vibration and the resonance frequency of the longitudinal vibration of the vibrating body 12 are the same. Thereby, the piezoelectric drive device 100 can rotate the rotor 4 efficiently.

  As shown in FIG. 8, the motor 120 according to the present embodiment includes the piezoelectric driving device (piezoelectric driving device 100 in the illustrated example) according to the present invention and the rotor 4 rotated by the piezoelectric driving device 100.

  The piezoelectric drive device 100 has the following features, for example.

The piezoelectric driving device 100 includes a first contact hole 60 provided so as to penetrate to the upper surface 32a of the first electrode 32 at a position where the second electrode 36 of the piezoelectric layer 34 is not provided. Therefore, in the piezoelectric driving device 100, the piezoelectric layer 34 is provided in addition to the portion directly below the second electrode 36. Therefore, in the piezoelectric driving device 100, the flatness of the bonding surface 101a of the vibration unit 102 can be improved as compared with the case where the piezoelectric layer 34 is provided only directly below the second electrode 36. Thereby, in the piezoelectric drive device 100, the bonding area can be increased between the adjacent vibration units 102, and the bonding strength between the adjacent vibration units 102 can be increased.

  Further, in the piezoelectric driving device 100, since the piezoelectric layer 34 is provided other than directly below the second electrode 36, the first electrode 32 and the first electrode 32 passing through the surface of the piezoelectric layer 34 as shown in FIG. The path length K between the two electrodes 36 can be increased. For example, as shown in FIG. 10, when the piezoelectric layer 34 is provided only directly below the second electrode 36, the gap between the first electrode 32 and the second electrode 36 that passes through the surface of the piezoelectric layer 34. The path length K becomes shorter. Therefore, in the piezoelectric driving device 100, for example, even if moisture adheres to the surface of the piezoelectric layer 34 (the surface in contact with the first insulating layer 40), the path length K is long. Therefore, it is possible to prevent the first electrode 32 and the second electrode 36 from being short-circuited (see “3. Experimental example” described later). As a result, the piezoelectric drive device 100 can improve durability.

  Furthermore, in the piezoelectric driving device 100, since the piezoelectric layer 34 is provided other than just below the second electrode 36, the occurrence of cracks in the piezoelectric layer 34 can be suppressed (see “3. Refer to experimental example "). Therefore, in the piezoelectric driving device 100, the durability of the piezoelectric layer 134 can be improved and the withstand voltage can be increased. It is assumed that the crack of the piezoelectric layer 34 can be suppressed because the deformation of the active portion 34a can be suppressed by the inactive portion 34b.

  Further, in the piezoelectric driving device 100, since the piezoelectric layer 34 is provided other than just below the second electrode 36, it is possible to suppress the occurrence of separation between the substrate 10 and the first electrode 32. (Refer to “3. Experimental example” described later). Therefore, the piezoelectric drive device 100 can improve the reliability.

  In the piezoelectric drive device 100, the piezoelectric layer 34 is continuous with the active portion 34 a sandwiched between the first electrode 32 and the second electrode 36, and is sandwiched between the first electrode 32 and the second electrode 36. The first contact hole 60 is provided in the non-active part 34b. Therefore, in the piezoelectric driving device 100, the bonding strength between the adjacent vibration units 102 can be increased as described above.

  In the piezoelectric driving device 100, the first insulating layer 40 is provided so as to cover the upper surface 36 a and the side surface 36 b of the second electrode 36, the upper surface 35 of the piezoelectric layer 34, and the inner surface 60 a of the first contact hole 60. The insulating layer 40 is included, and the first insulating layer 40 is an inorganic insulating layer. Therefore, in the piezoelectric driving device 100, it is possible to suppress moisture from adhering to the surface of the piezoelectric layer 34, and the first electrode 32 and the second electrode 36 are short-circuited through the moisture on the surface of the piezoelectric layer 34. (Refer to “3. Experimental example” described later). As a result, the piezoelectric drive device 100 can improve durability.

  In the piezoelectric driving device 100, the insulating layers 42 and 44 have photosensitivity. Therefore, the insulating layers 42 and 44 can be patterned by exposure, development, and baking without using etching. Therefore, in the piezoelectric driving device 100, cost reduction can be achieved.

2. Next, a method for manufacturing the piezoelectric drive device 100 according to the present embodiment will be described with reference to the drawings. FIG. 11 is a flowchart for explaining a method of manufacturing the piezoelectric driving device 100 according to this embodiment. 12-15 is sectional drawing which shows typically the manufacturing process of the piezoelectric drive device 100 which concerns on this embodiment.

  As shown in FIG. 12, the 1st electrode 32 is formed on the vibrating body part 12 of the board | substrate 10 (S1). The first electrode 32 is formed by, for example, film formation by sputtering, CVD, vacuum deposition, or the like, and patterning (patterning by photolithography and etching). The substrate 10 is obtained, for example, by forming the base layer 11b on the silicon substrate 11a by sputtering or CVD.

  Next, the piezoelectric layer 34 is formed on the first electrode 32 (S2). The piezoelectric layer 34 is formed, for example, by repeating the formation of a precursor layer by a liquid phase method and the crystallization of the precursor layer. The liquid phase method is a method of forming a thin film material using a raw material liquid containing a constituent material of a thin film (piezoelectric layer), and specifically, a sol-gel method, a MOD (Metal Organic Deposition) method, or the like. . Crystallization is performed by, for example, heat treatment at 700 ° C. to 800 ° C. in an oxygen atmosphere.

  Next, the second electrode 36 is formed on the piezoelectric layer 34 (S3). The second electrode 36 is formed by the same method as the first electrode 32, for example. The second electrode 36 is formed so that a part of the upper surface of the piezoelectric layer 34 is exposed. Thereby, the piezoelectric layer 34 having the active part 34a and the inactive part 34b can be formed.

  Through the above steps, the piezoelectric element 30 can be formed on the vibrating body portion 12 of the substrate 10.

  As shown in FIG. 13, the first contact hole 60 is formed in the inactive portion 34b of the piezoelectric layer 34 (S4). That is, the first contact hole 60 is formed in a region where the second electrode 36 of the piezoelectric layer 34 is not formed. In this step, the portion of the piezoelectric layer 34 other than the portion where the first contact hole 60 is formed is left as it is. The first contact hole 60 is formed by patterning the inactive portion 34b by photolithography and etching.

  As shown in FIG. 14, the first insulation covers the upper surface 36a and side surface 36b of the second electrode 36, the upper surface 35 of the piezoelectric layer 34, the upper surface 32a of the first electrode 32, and the inner surface 60a of the first contact hole 60. The layer 40 is formed (S5). The first insulating layer 40 is formed by, for example, the ALCVD (Atomic Layer Chemical Vapor Deposition) method or the CVD (Chemical Vapor Deposition) method.

  Next, second contact holes 62a and 62b are formed in the first insulating layer 40 (S6). The second contact holes 62a and 62b are formed by patterning the first insulating layer 40 by photolithography and etching.

  As shown in FIG. 15, the first conductive layer 54 constituting the first wiring layer 50 and the second wiring layer 52 is formed on the first insulating layer 40 (S7). The first conductive layer 54 is formed by, for example, film formation by sputtering and patterning.

  Next, the second insulating layer 42 is formed on the first insulating layer 40 and the first conductive layer 54 (S8). The second insulating layer 42 is formed by, for example, a spin coat method.

  Next, the third contact hole 64 is formed in the second insulating layer 42 (S9). The third contact hole 64 is formed by patterning the second insulating layer 42 by photolithography.

  As shown in FIG. 4, the second conductive layer 56 is formed on the second insulating layer 42 (S10). The second conductive layer 56 is formed in the same manner as the first conductive layer 54, for example.

  Next, the third insulating layer 44 is formed on the second insulating layer 42 and the second conductive layer 56 (S11). The third insulating layer 44 is formed by, for example, a spin coat method.

  Through the above steps, the vibration units 102a and 102b can be formed.

  As shown in FIG. 2, the vibration units 102a and 102b are joined (S12). The vibration units 102a and 102b are joined via the adhesive 2, for example.

  The piezoelectric driving device 100 can be manufactured through the above steps.

  In the method for manufacturing the piezoelectric driving device 100, as described above, the piezoelectric driving device 100 that can increase the bonding strength between the adjacent vibration units 102 can be manufactured.

3. Experimental Example An experimental example is shown below to describe the present invention more specifically. The present invention is not limited by the following experimental examples.

3.2. Pulse endurance test 3.1.1. Samples Experiments were performed using samples A, B, C, and D as shown in FIGS.

  In Sample A, as shown in FIG. 16, the first electrode 132 is formed on the substrate 111, the piezoelectric layer 134 is formed on the first electrode 132, and the second electrode 136 is formed on the piezoelectric layer 134. Then, an organic insulating layer 142 was formed so as to cover the piezoelectric layer 134 and the electrodes 132 and 136, and a conductive layer 154 electrically connected to the electrodes 132 and 136 was formed. In the sample A, the piezoelectric layer 134 has only the active part 134a located immediately below the second electrode 136, and does not have the inactive part 134b.

  As shown in FIG. 17, sample B is the same as sample A except that piezoelectric layer 134 has active portion 134a and inactive portion 134b.

  As shown in FIG. 18, the sample C is the same as the sample except that the inorganic insulating layer 140 is formed so as to cover the piezoelectric layer 134 and the electrodes 132 and 136, and the organic insulating layer 142 is formed on the inorganic insulating layer 140. Same as A.

  The sample D is the same as the sample C except that the piezoelectric layer 134 has an active part 134a and an inactive part 134b as shown in FIG.

In Samples A to D, the substrate 111 was a stack of a silicon substrate, a silicon oxide layer provided on the silicon substrate, and a zirconium oxide layer provided on the silicon oxide layer. In Samples A to D, the material of the piezoelectric layer 134 was PZT, and the material of the organic insulating layer 142 was an epoxy resin. In Samples A to D, the conductive layer 154 was a stacked body of a titanium tungsten layer and a copper layer provided on the titanium tungsten layer. Sample C
, D, the material of the inorganic insulating layer 140 is tantalum oxide, and the thickness of the inorganic insulating layer 140 is 90 nm.

3.1.2. Test Results In samples A to D as described above, a waveform having a sine wave of 20 kHz and an amplitude of 100 V (0 to 100 V) was applied to 40 samples (N = 40) at room temperature (25 ° C.). Specifically, the above waveform was applied to the second electrode 136 using the first electrode 132 as a grant. And the relationship of the destruction incidence with respect to the application time was investigated. FIG. 20 is a table showing the relationship between the pulse application time and the breakdown occurrence rate. FIG. 21 is a graph showing the relationship between the pulse application time and the breakdown occurrence rate. “Destruction” means a state in which the first electrode and the second electrode are short-circuited.

  As shown in FIG. 20 and FIG. 21, in Samples A and B, the pulse occurrence time was less than 50 hours, and the breakdown occurrence rate exceeded 50%. This is because the samples A and B do not have the inorganic insulating layer 140, so that moisture passes through the epoxy resin and adheres to the side surface of the piezoelectric layer 134, and the first electrode 132 and the second electrode 136 are short-circuited. This is because. Therefore, it was found that the inorganic insulating layer 140 has a high moisture barrier property and can improve durability.

  Furthermore, sample B had a lower failure rate than sample A, and sample C had a lower failure rate than sample D. This is because the samples B and D have the inactive portion 134b, and therefore the path between the first electrode 132 and the second electrode 136 that passes through the surface of the piezoelectric layer 134 as compared with the samples A and C. This is because the length is long. Therefore, it has been found that the durability can be improved when the piezoelectric layer 134 has the inactive portion 134b.

3.2. DC crack test 3.2.1. Sample An experiment was performed using samples E and F as shown in FIGS. In the following experimental examples, members having the same functions as those of Samples A to D described above are denoted by the same reference numerals, and detailed description thereof is omitted.

  In Sample E, as shown in FIG. 22, the first electrode 132 is formed on the substrate 111, the piezoelectric layer 134 is formed on the first electrode 132, and the second electrode 136 is formed on the piezoelectric layer 134. . In the sample A, the piezoelectric layer 134 has only the active part 134a located immediately below the second electrode 136, and does not have the inactive part 134b.

  As shown in FIG. 23, the sample F is the same as the sample E except that the piezoelectric layer 134 has an active part 134a and an inactive part 134b.

3.2.2. Test Results In Samples E and F as described above, a voltage of 100 V was applied between the electrodes 132 and 136, and then cracks in the piezoelectric layer 34 were confirmed using a metal microscope. 24 and 25 are metallographic micrographs after a voltage of 100 V is applied between the electrodes 132 and 136, FIG. 24 is the result of sample E, and FIG. 25 is the result of sample F.

  As shown in FIGS. 24 and 25, in sample E, it was confirmed that cracks were generated in the piezoelectric layer 134 through the second electrode 136. On the other hand, in sample F, no cracks in the piezoelectric layer 134 were confirmed. Therefore, it has been found that the durability can be improved and the breakdown voltage can be increased by having the inactive portion 134b in the piezoelectric layer 134.

3.3. Tape peeling test (cross cut method)
3.2.1. Sample Experiments were performed using samples G, H, I, J, and K as shown in FIGS.

  In sample G, as shown in FIG. 26, the first electrode 132 is formed on the substrate 111, the piezoelectric layer 134 is formed on the first electrode 132, and the second electrode 136 is formed on the piezoelectric layer 134. The inorganic insulating layer 140 is formed over the second electrode 136, the organic insulating layer 142 is formed over the inorganic insulating layer 140, and the conductive layer 154 electrically connected to the second electrode 136 is formed over the organic insulating layer 142. Formed. The material of the inorganic insulating layer 140 was tantalum oxide, and the thickness of the inorganic insulating layer 140 was 90 nm.

  As shown in FIG. 27, the sample H is the same as the sample G except that the piezoelectric layer 134 and the second electrode 136 are not formed and the conductive layer 154 is electrically connected to the first electrode 132. is there.

  As shown in FIG. 28, Sample I is the same as Sample H except that a piezoelectric layer 134 is formed in a portion between the first electrode 132 and the inorganic insulating layer 140.

  In Sample J, the first electrode 132 was formed on the substrate 111 as shown in FIG.

  In Sample K, as shown in FIG. 30, the first electrode 132 was formed on the substrate 111, and the conductive layer 154 was formed on the first electrode 132.

3.2.2. Test Results In the samples G to K as described above, the laminate as described above is repeatedly formed on one surface of the wafer. As shown in FIG. 31, 6 × 6 cuts 8 are made at 1 mm intervals on the surface of the wafer 6 on which the laminate is formed, and each of the samples G to K is 5 × 5 = 25. Divided into pieces. Each of the divided 25 samples G to K has a structure as shown in FIGS. The cut 8 reaches the substrate 111. Cellotape (registered trademark) was strongly pressed on the divided 25 samples, and the end of the tape was inclined 45 ° with respect to the horizontal direction and peeled off at once. And the number which peeled in 25 pieces and the position of the peeled interface were confirmed. FIG. 32 is a table showing the number of the 25 samples peeled and the position of the interface where the peeling occurred in samples G to K.

  As shown in FIG. 32, no sample I was peeled off, but all the samples H were peeled off at the interface between the first electrode 132 and the substrate 111. Therefore, it has been found that the formation of the piezoelectric layer 134 on a part of the first electrode 132 can suppress peeling and improve reliability. Thereby, it can be said that since the piezoelectric layer has the inactive portion, the region of the piezoelectric layer formed on the first electrode can be increased correspondingly, and the reliability can be improved.

Further, none of the samples J were peeled off, but all the samples K were peeled off at the interface between the first electrode 132 and the substrate 111. Accordingly, when the stress of the conductive layer 154 is applied to the first electrode 132, the peeling occurs at the interface between the first electrode 132 and the substrate 111 (specifically, the interface between the first electrode 132 and zirconium oxide (ZrO ₂ )). Was found to occur. Therefore, it can be seen that it is more effective to leave the piezoelectric layer 134 around the contact portion of the conductive layer 154 with the first electrode 132 as in Sample I in order to suppress peeling. It was.

4). Device Using Piezoelectric Drive Device An electric drive device according to the present invention can apply a large force to a driven body by utilizing resonance, and can be applied to various devices. The piezoelectric drive device according to the present invention is
For example, it can be used as a drive device in various devices such as a robot (including an electronic component conveying device (IC handler)), a medication pump, a clock calendar feeding device, and a paper feeding mechanism of a printing device. Hereinafter, representative embodiments will be described. Hereinafter, an apparatus including the piezoelectric driving apparatus 100 will be described as the piezoelectric driving apparatus according to the present invention.

4.1. Robot FIG. 33 is a diagram for explaining a robot 2050 using the piezoelectric driving device 100. The robot 2050 includes an arm 2010 (a plurality of link portions 2012 (also referred to as “link members”) and a plurality of joint portions 2020 that connect the link portions 2012 in a rotatable or bendable state. It is also called “arm”.

  Each joint portion 2020 includes a piezoelectric drive device 100, and the joint portion 2020 can be rotated or bent by an arbitrary angle using the piezoelectric drive device 100. A robot hand 2000 is connected to the tip of the arm 2010. The robot hand 2000 includes a pair of grip portions 2003. The robot hand 2000 also has a built-in piezoelectric driving device 100, and the piezoelectric driving device 100 can be used to open and close the gripping unit 2003 to grip an object. Further, the piezoelectric driving device 100 is also provided between the robot hand 2000 and the arm 2010, and the robot hand 2000 can be rotated with respect to the arm 2010 using the piezoelectric driving device 100.

  FIG. 34 is a view for explaining the wrist portion of the robot 2050 shown in FIG. The wrist joint portion 2020 sandwiches the wrist rotating portion 2022, and the wrist link portion 2012 is attached to the wrist rotating portion 2022 so as to be rotatable around the central axis O of the wrist rotating portion 2022. . The wrist rotation unit 2022 includes the piezoelectric driving device 100, and the piezoelectric driving device 100 rotates the wrist link unit 2012 and the robot hand 2000 around the central axis O. The robot hand 2000 is provided with a plurality of gripping units 2003. The proximal end portion of the grip portion 2003 is movable in the robot hand 2000, and the piezoelectric drive device 100 is mounted on the base portion of the grip portion 2003. For this reason, by operating the piezoelectric driving device 100, the gripping portion 2003 can be moved to grip the target. The robot is not limited to a single-arm robot, and the piezoelectric drive device 100 can be applied to a multi-arm robot having two or more arms.

  Here, in the wrist joint 2020 and the robot hand 2000, in addition to the piezoelectric drive device 100, a power line for supplying power to various devices such as a force sensor and a gyro sensor, a signal line for transmitting a signal, and the like And requires a lot of wiring. Therefore, it is very difficult to arrange wiring inside the joint portion 2020 and the robot hand 2000. However, since the piezoelectric drive device 100 can reduce the drive current as compared with a normal electric motor, wiring can be arranged even in a small space such as the joint portion 2020 (particularly, the joint portion at the tip of the arm 2010) or the robot hand 2000. Is possible.

4.2. Pump FIG. 35 is a diagram for explaining an example of a liquid feed pump 2200 using the piezoelectric driving device 100. The liquid feed pump 2200 includes a reservoir 2211, a tube 2212, a piezoelectric driving device 100, a rotor 2222, a deceleration transmission mechanism 2223, a cam 2202, a plurality of fingers 2213, 2214, 2215, 2216, and a case 2230. 2217, 2218, 2219.

The reservoir 2211 is a storage unit for storing a liquid to be transported. The tube 2212 is a tube for transporting the liquid sent out from the reservoir 2211. The contact portion 20 of the piezoelectric driving device 100 is provided in a state of being pressed against the side surface of the rotor 2222, and the piezoelectric driving device 100 rotates the rotor 2222. The rotational force of the rotor 2222 is transmitted to the cam 2202 via the deceleration transmission mechanism 2223. Fingers 2213 to 2219 are members for closing the tube 2212. When the cam 2202 rotates, the fingers 2213 to 2219 are sequentially pushed outward in the radial direction by the protrusion 2202A of the cam 2202. The fingers 2213 to 2219 close the tube 2212 in order from the upstream side in the transport direction (reservoir 2211 side). Thereby, the liquid in the tube 2212 is transported to the downstream side in order. In this way, it is possible to realize a small liquid feed pump 2200 that can feed a very small amount with high accuracy.

  In addition, arrangement | positioning of each member is not restricted to what was illustrated. Further, a member such as a finger may not be provided, and a ball or the like provided on the rotor 2222 may close the tube 2212. The liquid feed pump 2200 as described above can be used for a medication device that administers a drug solution such as insulin to the human body. Here, since the drive current can be made smaller than that of a normal electric motor by using the piezoelectric drive device 100, the power consumption of the dosing device can be suppressed. Therefore, it is particularly effective when the medication apparatus is battery-driven.

  The present invention includes configurations that are substantially the same as the configurations described in the embodiments (for example, configurations that have the same functions, methods, and results, or configurations that have the same objects and effects). In addition, the invention includes a configuration in which a non-essential part of the configuration described in the embodiment is replaced. In addition, the present invention includes a configuration that exhibits the same operational effects as the configuration described in the embodiment or a configuration that can achieve the same object. Further, the invention includes a configuration in which a known technique is added to the configuration described in the embodiment.

2 ... Adhesive, 4 ... Rotor, 4a ... Center, 6 ... Wafer, 8 ... Cut, 10 ... Substrate, 10a ... First surface, 10b ... Second surface, 11a ... Silicon substrate, 11b ... Underlayer, 12 ... Vibration Body part, 12a ... concave part, 14 ... support part, 16 ... first connection part, 18 ... second connection part, 20 ... contact part, 30, 30a, 30b, 30c, 30d, 30e ... piezoelectric element, 32 ... first Electrode, 32a ... Upper surface, 34 ... Piezoelectric layer, 34a ... Active portion, 34b ... Inactive portion, 35 ... Upper surface, 36 ... Second electrode, 36a ... Upper surface, 36b ... Side surface, 40 ... First insulating layer, 42 ... 2nd insulating layer, 44 ... 3rd insulating layer, 50 ... 1st wiring layer, 52 ... 2nd wiring layer, 54 ... 1st conductive layer, 54a ... Upper surface, 56 ... 2nd conductive layer, 60 ... 1st contact hole 60a ... inner surface, 62a, 62b ... second contact hole, 64 ... third contact 100 ... piezoelectric drive device, 101 ... structure, 101a ... bonding surface, 102 ... vibration unit, 102a ... first vibration unit, 102b ... second vibration unit, 110 ... drive circuit, 111 ... substrate, 120 ... motor, 132 ... first electrode, 134 ... piezoelectric layer, 134a ... active portion, 134b ... inactive portion, 136 ... second electrode, 140 ... inorganic insulating layer, 142 ... organic insulating layer, 154 ... conductive layer, 2000 ... robot hand , 2003 ... gripping part, 2010 ... arm, 2012 ... link part, 2020 ... joint part, 2050 ... robot, 2200 ... liquid feed pump, 2202 ... cam, 2202 A ... projection part, 2211 ... reservoir, 2212 ... tube, 2213, 2214 , 2215, 2216, 2217, 2218, 2219 ... finger, 2222 ... rotor 2223 ... the reduction-transmission mechanism, 2230 ... case

Claims (9)

A piezoelectric drive device including a plurality of vibration units,
The vibration unit is
A diaphragm,
A first electrode provided on the diaphragm;
A piezoelectric layer provided on the first electrode;
A second electrode provided on the piezoelectric layer;
A contact hole provided so as to penetrate to the upper surface of the first electrode at a position where the second electrode of the piezoelectric layer is not provided;
A wiring layer electrically connected to the first electrode or the second electrode through the contact hole;
Including
The piezoelectric driving device, wherein the plurality of vibration units are arranged so as to overlap in a thickness direction of the diaphragm. In claim 1,
The piezoelectric layer is
An active part sandwiched between the first electrode and the second electrode;
An inactive portion that is continuous with the active portion and is not sandwiched between the first electrode and the second electrode;
Have
The contact hole is provided in the inactive portion, the piezoelectric driving device. In claim 1 or 2,
A protective layer provided to cover the upper and side surfaces of the second electrode, the upper surface of the piezoelectric layer, and the inner surface of the contact hole;
The piezoelectric driving device, wherein the protective layer is an inorganic insulating layer. A method of manufacturing a piezoelectric drive device including a plurality of vibration units,
Forming a first electrode on the diaphragm;
Forming a piezoelectric layer on the first electrode;
Forming a second electrode on the piezoelectric layer;
Forming a contact hole at a position where the second electrode of the piezoelectric layer is not formed so as to penetrate to the upper surface of the first electrode;
Forming a wiring layer electrically connected to the first electrode or the second electrode through the contact hole;
Forming a plurality of the vibration units,
A method for manufacturing a piezoelectric drive device, wherein a plurality of the vibration units are arranged so as to overlap in a thickness direction of the vibration plate. In claim 4,
The piezoelectric layer is
An active part sandwiched between the first electrode and the second electrode;
An inactive portion that is continuous with the active portion and is not sandwiched between the first electrode and the second electrode;
Formed to have
The method for manufacturing a piezoelectric driving device, wherein the contact hole is formed in the inactive portion. In claim 4 or 5,
Forming a protective layer so as to cover the upper and side surfaces of the second electrode, the upper surface of the piezoelectric layer, and the inner surface of the contact hole;
The method for manufacturing a piezoelectric driving device, wherein the material of the protective layer is an inorganic insulating layer. A piezoelectric driving device according to any one of claims 1 to 3,
A rotor rotated by the piezoelectric drive device;
Including a motor. A plurality of link parts;
A joint part connecting a plurality of the link parts;
The piezoelectric drive device according to any one of claims 1 to 3, wherein a plurality of the link portions are rotated by the joint portions;
Including robots. A piezoelectric driving device according to any one of claims 1 to 3,
A tube that transports the liquid;
A plurality of fingers for closing the tube by driving the piezoelectric driving device;
Including a pump.