JP6737994B2 - motor - Google Patents

Description

The present invention relates to a motor.

A conventional permanent magnet motor is a motor in which a permanent magnet is embedded inside a rotor (rotor) core. The motor having this configuration can use both the magnet torque generated by the attraction and repulsion of the permanent magnet and the reluctance torque produced by the coil attracting the rotor iron core, and can achieve high efficiency (for example, patent Reference 1).

In the conventional permanent magnet motor described above, it is easy to increase the torque when the rotor rotates at high speed, but it is not easy to increase the torque when the rotor rotates at low speed. Therefore, there is a demand for a motor that can easily increase the torque when the rotor rotates at a low speed.

JP, 10-136592, A

An object of one embodiment of the present invention is to provide a motor that can easily increase torque during low-speed rotation.

Various aspects of the present invention will be described below.
[1] A motor having a rotor and a stator,
The rotor includes a ring-shaped rotor, a first N-pole permanent magnet, a first S-pole permanent magnet, a second N-pole permanent magnet, and a second N-pole permanent magnet arranged on the inner circumference of the rotor. And an S-pole permanent magnet,
The stator includes a ring-shaped stator, a plurality of piezoelectric elements and a plurality of electromagnets arranged along the stator,
The motor, wherein each of the plurality of piezoelectric elements has a piezoelectric body sandwiched between a first electrode and a second electrode.

[2] In the motor described in [1] above,
The piezoelectric body may be a bulk piezoelectric body or a film piezoelectric body.

[3] In the motor described in [2] above,
The first electrode is a first conductive film or a first ferromagnetic film,
The motor, wherein the second electrode is a second conductive film or a second ferromagnetic film.

[4] In the motor described in [2] or [3] above,
Each of the plurality of piezoelectric elements includes a single crystal substrate, the first electrode oriented on the single crystal substrate, the film-shaped piezoelectric body disposed on the first electrode, and A second electrode arranged on the film-shaped piezoelectric body.

[5] In the motor described in [4] above,
A motor having a first film disposed between the single crystal substrate and the first electrode and oriented on the single crystal substrate.

[6] In the motor described in [5] above,
The single crystal substrate is a silicon substrate,
The motor, wherein the first film is a metal oxide film that is more easily oxidized than silicon.

[7] In the motor described in [3] above,
The motor, wherein each of the first and second ferromagnetic films is a metal film.

[8] In the motor described in [6] above,
The silicon substrate has a main surface composed of (100) planes,
The motor according to claim 1, wherein the first film has a cubic crystal structure and contains (100)-oriented zirconium oxide.

[9] In the motor according to any one of [2] to [8] above,
The film-shaped piezoelectric body has a tetragonal crystal structure and includes (001)-oriented lead zirconate titanate.

[10] In the motor according to any one of the above [2] to [8],
The film-shaped piezoelectric body has a rhombohedral crystal structure and includes (100) oriented lead zirconate titanate.

[11] In the motor according to any one of [2] to [8],
The film-shaped piezoelectric body is a (Pb _a La _b )(Zr _c Ti _d Nb _e )O _3-δ film having a film thickness of 5 μm or more,
a, b, c, d, e and δ satisfy the following formulas 1 to 7,
Wherein _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film has a specific dielectric constant of 100 or more and 600 or less,
Wherein _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film, the coercive voltage and 20 [mu] C / cm ² or more 50 .mu.C / cm ² or less of residual polarization value of 15V per following thickness 1μm or 3V A motor having at least one.
0≦δ≦1 Equation 1
1.00≦a+b≦1.35 Formula 2
0≦b≦0.08 Equation 3
1.00≦c+d+e≦1.1...Equation 4
0.4≦c≦0.7 Equation 5
0.3≦d≦0.6 Formula 6
0≦e≦0.1 Formula 7

[12] In the motor described in [11] above,
The peak value of _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film XRD of (002) is higher than the peak value of (200) of XRD of the first electrode, the motor.

[13] In the motor described in [12] above,
The motor, wherein the first electrode comprises a Pt film.

[14] In the motor according to any one of [11] to [13] above,
The Curie temperature of _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film is 250 ° C. or higher 420 ° C. or less, the motor.

The motor as the piezoelectric magnet motor in this specification can be used in various products such as hybrid cars, electric cars, home appliances, and electronic devices.

In addition, in various aspects of the present invention described above, a specific C (hereinafter referred to as “C”) is formed (a C is formed) above (or below) a specific B (hereinafter referred to as “B”). At this time, the present invention is not limited to the case where C is directly formed on (or below) B (C is formed), and is not limited to the range above (or below) B to the effect of one embodiment of the present invention. It also includes a case where C is formed (C is formed) through another.

In addition, in the various aspects of the present invention described above, an aspect in which the vertical direction is reversed is also included. In other words, it does not mean that a mode in which the piezoelectric element is turned upside down is excluded.

By applying one embodiment of the present invention, a motor that can easily increase torque during low-speed rotation can be provided.

It is a top view explaining the piezoelectric magnet motor provided with the piezoelectric stepping motor and the permanent magnet motor. It is a right-handed screw coil showing an example of the electromagnet shown in FIGS. 1(B) and 1(C). It is sectional drawing of the piezoelectric element of 1st Embodiment. It is a schematic diagram which shows a part of piezoelectric magnet motor shown in FIG.1(C). It is a schematic diagram which shows the method of operating the piezoelectric stepping motor in the piezoelectric magnet motor shown in FIG.1(C). It is a figure explaining the state which the film of each layer contained in a piezoelectric element epitaxially grew. 3 is a graph showing the voltage dependence of polarization of the film-shaped piezoelectric material included in the piezoelectric element of the first embodiment. FIG. 6 is a cross-sectional view during a manufacturing process of the piezoelectric element of the first embodiment. FIG. 6 is a cross-sectional view during a manufacturing process of the piezoelectric element of the first embodiment. FIG. 6 is a cross-sectional view during a manufacturing process of the piezoelectric element of the first embodiment. FIG. 6 is a cross-sectional view during a manufacturing process of the piezoelectric element of the first embodiment. It is sectional drawing of the piezoelectric element of the modification of 1st Embodiment. FIG. 7 is a cross-sectional view during a manufacturing process of the piezoelectric element of the modified example of the first embodiment. FIG. 7 is a cross-sectional view during a manufacturing process of the piezoelectric element of the modified example of the first embodiment. It is sectional drawing of the piezoelectric element of 2nd Embodiment. It is sectional drawing in the manufacturing process of the piezoelectric element of 2nd Embodiment. It is sectional drawing in the manufacturing process of the piezoelectric element of 2nd Embodiment. It is a sectional view showing typically a sputtering device concerning one mode of the present invention. It is a figure explaining the case of a DUTY ratio of 100S/T%. It is a schematic diagram of an oxygen-deficient perovskite structure in the case of δ=0.125, or n=8.0. It is a schematic diagram of an oxygen-deficient perovskite structure in the case of δ=0.25 or n=4.0. It is a schematic diagram of an oxygen-deficient perovskite structure in the case of δ=0.5 or n=2.0. FIG. 3 is a schematic diagram of an oxygen-deficient perovskite structure when δ=1.0 or n=1.0. (A)-(D) is sectional drawing for demonstrating the manufacturing method of the piezoelectric element which concerns on 1 aspect of this invention. (A) is a plan view illustrating a method for manufacturing a piezoelectric element according to an aspect of the present invention, and (B) is a cross-sectional view illustrating a method for manufacturing a piezoelectric element according to an aspect of the present invention. (A) And (B) is sectional drawing for demonstrating the manufacturing method of the piezoelectric element which concerns on 1 aspect of this invention. (A) is a plan view illustrating a method for manufacturing a piezoelectric element according to an aspect of the present invention, and (B) is a cross-sectional view illustrating a method for manufacturing a piezoelectric element according to an aspect of the present invention. FIG. 6A is a plan view illustrating a method for manufacturing a piezoelectric element according to an aspect of the present invention, and FIG. 6B is a cross-sectional view illustrating a method for manufacturing a piezoelectric element according to an aspect of the present invention. (A)-(C) is sectional drawing for demonstrating the manufacturing method of the piezoelectric element which concerns on 1 aspect of this invention. (A)-(C) is sectional drawing for demonstrating the manufacturing method of the piezoelectric element which concerns on 1 aspect of this invention. (A)-(C) is sectional drawing for demonstrating the manufacturing method of the piezoelectric element which concerns on 1 aspect of this invention. (A)-(C) is sectional drawing for demonstrating the manufacturing method of the piezoelectric element which concerns on 1 aspect of this invention. (A)-(D) is sectional drawing for demonstrating the manufacturing method of the piezoelectric element which concerns on 1 aspect of this invention. (A) And (B) is sectional drawing for demonstrating the manufacturing method of the piezoelectric element which concerns on 1 aspect of this invention. (A) And (B) is sectional drawing for demonstrating the manufacturing method of the piezoelectric element which concerns on 1 aspect of this invention. (A)-(C) is sectional drawing for demonstrating the manufacturing method of the piezoelectric element which concerns on 1 aspect of this invention. 3 is an XRD pattern of the sample of Example 1. 3 is an XRD pattern of the sample of Example 2. 3 is an XRD pattern of the sample of Example 2. (A) is a cross-sectional image of the sample of Example 3 observed by FIB (Focused Ion Beam), and (B) is a cross-sectional image of the sample of Example 4 observed by FIB. 9 is an XRD chart of a PZT film of Example 3 and a PZT film of Example 4. It is an image figure of a reciprocal lattice map. It is a figure explaining the reciprocal lattice vector of a crystal lattice plane (hkl), and a reciprocal lattice point. It is a figure explaining the vector notation of an X-ray diffraction condition. (A)-(C) is a figure explaining reciprocal lattice mapping (method). It is a figure explaining reciprocal lattice mapping (method). It is a reciprocal lattice simulation result of a PZT single crystal. (A) and (B) are the results of reciprocal lattice map measurement of the samples of Example 3 (present invention 5 μm) and Example 4 (present invention 10 μm). (A) is a diagram showing the ferroelectric hysteresis curves of Example 3 (invention 5 μm), Example 4 (invention 10 μm) and Example 5 (invention 20 μm), and (B) is Example 3 to Example. It is a figure which shows each piezoelectric butterfly curve of Example 5. (A) is a diagram showing a ferroelectric hysteresis curve of Comparative Example 2 (K148), and (B) is a diagram showing a piezoelectric butterfly curve of Comparative Example 2 (K148). (A) is a diagram showing a ferroelectric hysteresis curve of Comparative Example 3 (K129), and (B) is a diagram showing a piezoelectric butterfly curve of Comparative Example 3 (K129). It is a figure which shows the result of having performed d33 evaluation of the PZT film of Example 5 (this invention 20 micrometer). (A) is a FIB-SEM image of the sample (20 μm-PZT film) of Example 5, and (B) is an enlarged image of (A). It is a figure which shows the result of having measured the temperature change of the relative dielectric constant and dielectric loss (tan(delta)) of the sample of Example 4 (this invention 10 micrometer), changing frequency to 100k, 500k, and 1MHz. FIG. 11 is a cross-sectional view showing a sample of Example 6; 9 is an XRD pattern of the sample of Example 6. 9 is an XRD pattern of the sample of Example 6. 6 is an image of a cross section of the sample of Example 7 observed by FIB.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following description, and it is easily understood by those skilled in the art that modes and details thereof can be variously modified without departing from the spirit and scope of the present invention. Therefore, the present invention should not be construed as being limited to the description of the embodiments below.

[First Embodiment]
<Piezoelectric magnet motor>
FIG. 1 is a plan view illustrating a piezoelectric magnet motor including a piezoelectric stepping motor and a permanent magnet motor. 1A is a plan view showing a rotor including a rotor and a permanent magnet, FIG. 1B is a plan view showing a stator including a piezoelectric element and an electromagnet, and FIG. It is a top view which shows the piezoelectric magnet motor which laminated|stacked the rotor shown to (A) and the stator shown to FIG. 1(B). FIG. 2 is a right-hand screw coil showing an example of the electromagnet shown in FIGS. 1(B) and 1(C).

As shown in FIG. 1A, the rotor 351 has a circular planar shape, and a ring-shaped rotor 301 is arranged on the outer periphery of the rotor 351. The rotor 301 has comb-teeth portions having a concavo-convex structure which are regularly arranged at a predetermined pitch (see FIG. 4 ). Inside the rotor 301, an N-pole permanent magnet 303, an S-pole permanent magnet 304, an N-pole permanent magnet 305, and an S-pole permanent magnet 306 are alternately arranged on the circumference. In addition, in the first embodiment, four permanent magnets are arranged inside the rotor 301, but five or more permanent magnets may be arranged inside the rotor.

As shown in FIG. 1B, the stator 352 has a stator 302 having a ring-shaped planar shape, and a plurality of piezoelectric elements 354 and a plurality of electromagnets 355 are arranged on the stator 302 along the ring shape. There is. Piezoelectric elements 354 and electromagnets 355 are arranged alternately. The electromagnets 355 are arranged on the circumference at intervals. The stator 302 has comb-teeth portions having a concavo-convex structure that are regularly arranged at a predetermined pitch (see FIG. 4 ).

As shown in FIG. 2, each of the plurality of electromagnets 355 has a core 355a and an insulated wire 355b wound around the core 355a. The core 355a is, for example, an iron core, and the insulated electric wire 355b is, for example, a wire formed by coating a copper wire or the like with an insulator. By passing a current i through the insulated wire 355b in the direction of the first arrow, it is possible to form an electromagnet having one of the cores 355a as the S pole, and in the direction of the second arrow (the direction opposite to the first arrow). By passing a current i through the coil, one of the cores 355a can be an electromagnet having an N pole.

Each of the plurality of piezoelectric elements 354 has a piezoelectric body sandwiched between a first electrode and a second electrode (not shown). The piezoelectric body may be a bulk piezoelectric body or a film piezoelectric body, which will be described in detail later.

<Bulk piezoelectric material>
A method for manufacturing a bulk piezoelectric body of Pb(Zr,Ti)O ₃ (hereinafter referred to as “PZT”) will be described.

The polycrystalline PZT powder is fired, the polycrystalline PZT powder is mixed with a resin, and the mixture is formed into a sheet to form a PZT sheet. By stacking the PZT sheets and baking them, a bulk piezoelectric body can be manufactured. The thickness of the one-layer PZT sheet after baking and hardening is 20 μm or more. The detailed manufacturing method of the bulk piezoelectric body is disclosed in, for example, Japanese Patent Publication No. 2013-518420.

In the first embodiment, the PZT bulk piezoelectric body is used as the piezoelectric body, but a bulk piezoelectric body other than PZT may be used as the piezoelectric body.

The piezoelectric magnet motor shown in FIG. 1C has a rotor 351 shown in FIG. 1A and a stator 352 shown in FIG. The rotor 351 is rotatably provided around a shaft 353 as a rotation center. As shown in FIG. 4, the outer periphery of the piezoelectric magnet motor is in a state in which the stator 302 is arranged on the piezoelectric element 354 and the rotor 301 is arranged on the stator 302.

The piezoelectric magnet motor shown in FIG. 1C has a permanent magnet motor including permanent magnets 303 to 306 of a rotor 351 and an electromagnet 355 of a stator 352. For example, the distribution of the magnetic field generated by all the electromagnets 355 along the clockwise direction, in which the polarity is reversed at a constant interval along the inner peripheral surface of the stator 352, is the center of rotation of the shaft 353. The current flowing through the electromagnet 355 is periodically changed so as to rotate as. Then, the rotor 351 rotates following the distribution of the magnetic field rotating around the shaft 353 as the center of rotation. In this way, the permanent magnet motor operates. The electric current supplied to the electromagnet 355 is supplied by a power source (not shown), and the power source is controlled by a controller (not shown).

In addition to this, in the piezoelectric magnet motor shown in FIG. 1C, the rotor 351 can be rotated by using the bulk piezoelectric material or the film piezoelectric material included in the piezoelectric element 354 as the piezoelectric stepping motor. .. Specifically, by alternately applying a positive voltage and a negative voltage between the first electrode and the second electrode of the piezoelectric element 354, the piezoelectric element 354 is expanded or contracted as shown in FIG. As a result, the stator 302 expands or contracts to move the rotor 301 while the comb teeth of the concavo-convex structure of the rotor 301 mesh with the comb teeth of the concavo-convex structure of the stator 302, and as a result, the rotor 351 is moved. The shaft 353 shown in FIG. 1C can be rotated about the rotation center (see FIG. 4). Note that FIGS. 4 and 5 show a part of FIG. 1C in detail, so that the rotor 301 and the stator 302 are linearly formed. However, FIG. Thus, the rotor 301 and the stator 302 have a shape arranged on the circumference. In this way, the piezoelectric stepping motor operates.

According to the piezoelectric magnet motor described above, since the piezoelectric stepping motor and the permanent magnet motor are included, it is possible to easily increase the torque during low speed rotation by using the piezoelectric stepping motor during low speed rotation of the rotor 301.

Further, by using the piezoelectric stepping motor and the permanent magnet motor simultaneously or separately, the rotational force and the rotational speed can be freely controlled. For example, a piezoelectric stepping motor is suitable for quick and powerful rotation, and a permanent magnet motor is suitable for high speed rotation. Therefore, by combining the piezoelectric stepping motor and the permanent magnet motor, it is possible to realize a motor that can be used for various purposes.

It will be described in more detail.

A piezoelectric stepping motor (ultrasonic motor) is a motor that moves a rotor using ultrasonic waves (frequency of 20 kHz or more) that cannot be heard by human ears. The ultrasonic motor uses a piezoelectric element for generating ultrasonic waves, and the piezoelectric element expands or contracts depending on the direction of the potential when a ±potential difference is applied to the two terminals. Ultrasonic waves are generated by this expansion and contraction.

The operation of the ultrasonic motor will be described.

First, as shown in FIG. 1B, piezoelectric elements 354 are attached at equal intervals on the plane of a circular metal plate called a stator 302, and every other piezoelectric element 354 is connected as shown in the upper diagram of FIG. , Add electrodes. When + and-potentials are alternately applied to this electrode (sine wave), the piezoelectric element 354 vibrates vertically as shown in the lower diagram of FIG. It is transmitted to the comb teeth. That is, as the sine wave of ±voltage applied between the electrodes progresses to the right, the protrusions of the comb teeth move up and down one after another, and when they follow the apex of the protrusions, a counterclockwise elliptical motion occurs.

The rotor 301 is installed so as to be in contact with the comb teeth on the stator 302 as shown in FIGS. 4 and 1C. A shaft 353 as a rotation shaft is installed at the center of the rotor 301. The rotor 301 rotates in the direction opposite to the traveling direction. This is the outline of the operating principle of the ultrasonic motor.

<Membrane piezoelectric material>
The film piezoelectric material will be described in detail below.

FIG. 3 is a sectional view of the piezoelectric element according to the first embodiment. This piezoelectric element 10 corresponds to the piezoelectric element 354 shown in FIG.

As shown in FIG. 3, the piezoelectric element 10 according to the first embodiment has a film-shaped piezoelectric body 14 as a piezoelectric film sandwiched between a first electrode 13 and a second electrode 15. Specifically, an alignment film (also referred to as a first film) 12 that is aligned on a predetermined surface is formed on the substrate 11, and a first electrode 13 is formed on the alignment film 12. The first electrode 13 is preferably a first conductive film or a ferromagnetic film (also referred to as a first ferromagnetic film). The second electrode 15 is preferably a second conductive film or a ferromagnetic film (also referred to as a second ferromagnetic film). In addition, the first electrode 13 is preferably formed on the substrate 11 while being oriented. Each of the first and second ferromagnetic films is preferably a metal film.

The substrate 11 may be a single crystal substrate, and the single crystal substrate includes a silicon (Si) substrate. The orientation film 12 is epitaxially grown on the substrate 11 and is oriented on the substrate 11. The alignment film 12 may be a metal oxide film that is more easily oxidized than the substrate 11, that is, an oxide film of a metal that is more easily oxidized than the substrate 11. If the substrate 11 is a silicon substrate, a metal oxide film that is more easily oxidized than silicon ( For example, a film containing zirconium and oxygen, a ZrO ₂ film, a CeO ₂ film, a HfO ₂ film, etc.) is preferable. The ferromagnetic film may be a permanent magnet film. The ferromagnetic film is epitaxially grown on the alignment film 12. Further, the ferromagnetic film is formed on the alignment film 12 while being oriented. The ferromagnetic film is preferably a metal film.

Since the above-mentioned ferromagnetic film is formed in an oriented manner, the characteristics of the ferromagnetic film can be improved as compared with a non-oriented ferromagnetic film. Further, there is an advantage that the ferromagnetic film is easily polarized when it is oriented.

Here, when two directions orthogonal to each other in the upper surface 11a as the main surface of the substrate 11 are the X-axis direction and the Y-axis direction and the direction perpendicular to the upper surface 11a is the Z-axis direction, a film is epitaxially grown. That is, it is preferable that the film be oriented in any of the X-axis direction, the Y-axis direction, and the Z-axis direction.

Preferably, the substrate 11 is made of silicon single crystal and has an upper surface 11a as a main surface composed of a (100) plane. The alignment film 12 may be epitaxially grown on the upper surface 11a of the (100) plane of the substrate 11. The orientation film 12 preferably has a cubic crystal structure and contains (100)-oriented zirconium oxide (ZrO ₂ ). For example, the alignment film 12 made of the (100)-oriented ZrO ₂ film is formed on the upper surface 11a made of the (100) plane of the substrate 11 made of silicon single crystal.

Here, that the orientation film 12 is (100) oriented means that the (100) plane of the orientation film 12 having a cubic crystal structure is the (100) plane of the substrate 11 made of silicon single crystal. It is preferable to extend along the upper surface 11a as the main surface, and preferably parallel to the upper surface 11a composed of the (100) surface of the substrate 11 composed of silicon single crystal. The (100) plane of the alignment film 12 is parallel to the upper surface 11a of the substrate 11 (100) only when the (100) plane of the alignment film 12 is completely parallel to the upper surface 11a of the substrate 11. Of course, this also includes the case where the angle formed by the plane perfectly parallel to the upper surface 11a of the substrate 11 and the (100) plane of the alignment film 12 is 20° or less.

Alternatively, as the alignment film 12, an alignment film 12 made of a laminated film may be formed on the substrate 11 instead of the alignment film 12 made of a single layer film.

When a permanent magnet film is used as the ferromagnetic film, a permanent magnet film containing a rare earth element, that is, a permanent magnet film made of a rare earth magnet can be used. Alternatively, as the permanent magnet film, a permanent magnet film other than the rare earth magnet can be used.

A film-shaped piezoelectric material 14 epitaxially grown is formed on the first electrode 13.

As the film-shaped piezoelectric body 14, a film-shaped piezoelectric body 14 containing lead zirconate titanate (PZT), that is, PbZr _x Ti _1-x O ₃ (0<x<1) can be used. Accordingly, the piezoelectric constant of the film-shaped piezoelectric body 14 can be increased as compared with the case where the film-shaped piezoelectric body 14 does not contain lead zirconate titanate.

When the film piezoelectric material 14 contains PZT, the film piezoelectric material 14 preferably has a tetragonal crystal structure and is (001) oriented. In PZT having a tetragonal crystal structure, large piezoelectric constants d33 and d31 are obtained when an electric field along the [001] direction is applied. Therefore, the piezoelectric constant of the film-shaped piezoelectric body 14 can be further increased.

When the film-shaped piezoelectric body 14 contains PZT, the film-shaped piezoelectric body 14 preferably has a rhombohedral crystal structure and is (100) oriented. In PZT having a rhombohedral crystal structure, large piezoelectric constants d33 and d31 are obtained when an electric field along the [100] direction is applied. Therefore, the piezoelectric characteristics of the film-shaped piezoelectric body 14 can be further increased.

According to the first embodiment, by forming one or both of the first electrode 13 and the second electrode 15 with a ferromagnetic film, the magnetic electrode functions as a ferrite core, and the rectifying action causes High frequency noise generated when a current flows is reduced, and as a result, piezoelectricity can be effectively taken out.

FIG. 6 is a diagram illustrating a state in which films of respective layers included in the piezoelectric element are epitaxially grown. In FIG. 6, as an example, a case where the first electrode 13 as a permanent magnet film as a ferromagnetic film contains Ni will be described. However, the same can be applied to cases other than the case where the first electrode 13 contains Ni.

When the first electrode 13 contains Ni, the lattice constant of Si contained in the substrate 11, the lattice constant of ZrO ₂ contained in the alignment film 12, the lattice constant of Ni contained in the first electrode 13, the piezoelectric film. The lattice constant of PZT contained in (piezoelectric film) 14 is as shown in the table of FIG.

Good match between the lattice constant of ZrO _{2 and} the lattice constant of Si. Therefore, the substrate including the alignment film 12 comprising ZrO _2, a silicon (100) on the principal surface made of a surface of the substrate 11 including the single crystal can be grown epitaxially, the alignment film 12 comprising ZrO _2, a silicon single crystal 11 can be (100)-oriented on the (100) plane, and the crystallinity of the alignment film 12 can be improved.

Further, the matching between the lattice constant of Ni and the lattice constant of ZrO ₂ is good. This is because the lattice constant of Ni is smaller than that of ZrO ₂ , but when Ni rotates 45° in the plane, the length of the diagonal line matches the a-axis of ZrO ₂ . Therefore, the first electrode 13 containing Ni can be epitaxially grown on the alignment film 12 containing ZrO _2, and the first electrode 13 containing Ni can be grown on the (100) plane of the alignment film 12 containing ZrO _2. In addition, the (100) orientation can be achieved, and the crystallinity of the first electrode 13 can be improved.

Further, the matching between the PZT lattice constant and the Ni lattice constant is good. Therefore, the film-shaped piezoelectric body 14 containing PZT can be epitaxially grown on the first electrode 13 containing Ni, and the film-shaped piezoelectric body 14 containing PZT is (100) of the first electrode 13 containing Ni. The (100) orientation can be achieved on the plane, and the crystallinity of the film-shaped piezoelectric body 14 can be improved.

As described above, in the first embodiment, the first electrode 13 and the film-shaped piezoelectric body 14 are epitaxially grown. As a result, the residual magnetization of the first electrode 13 can be increased as compared with the case where the first electrode 13 is not epitaxially grown, and the film-shaped piezoelectric body 14 is compared with the case where the film-shaped piezoelectric body 14 is not epitaxially grown. The piezoelectric constant of 14 can be increased.

FIG. 7 is a graph showing the voltage dependence of the polarization of the film-shaped piezoelectric material included in the piezoelectric element of the first embodiment. In other words, FIG. 7 is a graph showing a PV hysteresis curve. Further, in FIG. 7, the voltage dependence of the polarization of the film-shaped piezoelectric body 14 included in the piezoelectric element of the first embodiment is shown to be the voltage dependence of the polarization of the film-shaped piezoelectric body 14 included in the piezoelectric element of the comparative example. Shown together with. The film-shaped piezoelectric body 14 included in the piezoelectric element of the comparative example is not epitaxially grown by omitting the alignment film 12 or changing the film forming conditions, that is, the film included in the piezoelectric element of the comparative example. The piezoelectric body 14 has a direction perpendicular to the upper surface 11a as the main surface of the substrate 11 and two directions parallel to the upper surface 11a as the main surface of the substrate 11 and orthogonal to each other. Not oriented.

As shown in FIG. 7, in the film-shaped piezoelectric body 14 included in the piezoelectric element of the first embodiment, the voltage necessary for polarization reversal, that is, the coercive voltage is large, and for example, a positive voltage is reversed to a negative voltage. The absolute value of the coercive voltage is about 100V. On the other hand, the absolute value of the coercive voltage of the film-shaped piezoelectric body 14 included in the piezoelectric element of the comparative example is about 20V. The large coercive voltage means that the polarization of the film-shaped piezoelectric body 14 is stabilized by orienting the polarization axis of the film-shaped piezoelectric body 14 in the direction perpendicular to the upper surface 11a as the main surface of the substrate 11. To do. This means that even when a cyclically changing voltage is applied to the film-shaped piezoelectric body 14 to cause distortion to occur cyclically, the amount of distortion generated is stable without deterioration. Alternatively, even when a cyclically changing strain is applied to the film-shaped piezoelectric body 14 to cyclically generate a voltage, the generated voltage does not deteriorate and is stable.

Although illustration is omitted, similarly, when the first electrode 13 included in the piezoelectric element 10 of the first embodiment is a permanent magnet film, the magnetization reversal depends on the magnetic field dependence of the magnetization, that is, the magnetization hysteresis curve. The required voltage, that is, the holding power is large. The large coercive force means that the direction in which the permanent magnet film is easily magnetized is oriented in the direction perpendicular or parallel to the upper surface 11a as the main surface of the substrate 11, so that the residual magnetization of the permanent magnet film is stabilized. Means that. Then, it means that the residual magnetization of the permanent magnet film is stable without deterioration even when a periodically changing magnetic field is applied to the permanent magnet film.

<Method of Manufacturing Piezoelectric Element Having Membrane Piezoelectric Body>
Next, a method of manufacturing the piezoelectric element according to the first embodiment will be described with reference to FIGS. 8 to 11 are cross-sectional views of the piezoelectric element of the first embodiment during the manufacturing process.

First, as shown in FIG. 8, the substrate 11 is prepared (step S1). In step S1, the substrate 11 made of silicon single crystal is prepared. Further, preferably, the substrate 11 made of a silicon single crystal has a cubic crystal structure and has an upper surface 11a as a main surface made of the (100) plane. An oxide film such as a SiO ₂ film may be formed on the upper surface 11a of the substrate 11.

Next, as shown in FIG. 9, the alignment film 12 is formed on the substrate 11 (step S2). Hereinafter, the case where the alignment film 12 is formed by using the electron beam vapor deposition method will be described as an example, but the alignment film 12 can be formed by using various methods such as a sputtering method.

In step S2, first, the substrate 11 is placed in a constant vacuum atmosphere, and the substrate 11 is heated to 700° C. or higher (preferably 800° C. or higher).

Next, in step S2, Zr is evaporated by an electron beam evaporation method using an evaporation material of Zr single crystal. At this time, the evaporated Zr reacts with oxygen on the substrate 11 heated to 700° C. or higher to form a ZrO ₂ film. Then, the alignment film 12 made of the ZrO ₂ film as the single-layer film is formed.

As described above with reference to FIG. 3, the alignment film 12 is epitaxially grown on the upper surface 11a as the main surface of the (100) plane of the substrate 11 made of silicon single crystal. The alignment film 12 has a cubic crystal structure and contains (100)-oriented zirconium oxide (ZrO ₂ ). That is, the alignment film 12 made of a single layer film including the (100)-oriented ZrO ₂ film is formed on the upper surface 11a of the (100) plane of the substrate 11 made of silicon single crystal.

As described above, the two directions orthogonal to each other in the upper surface 11a formed of the (100) plane of the substrate 11 made of silicon single crystal are the X-axis direction (see FIG. 3) and the Y-axis direction (see FIG. 3), The direction perpendicular to the upper surface 11a is the Z-axis direction (see FIG. 3). At this time, when a certain film is epitaxially grown, it is preferable that the film be oriented in any of the X-axis direction, the Y-axis direction and the Z-axis direction.

The thickness of the alignment film 12 is preferably 2 nm to 100 nm, more preferably 10 nm to 50 nm. By having such a film thickness, it is possible to epitaxially grow and form the alignment film 12 that is extremely close to a single crystal.

Alternatively, as the alignment film 12, an alignment film 12 as a laminated film may be formed on the substrate 11 instead of the alignment film 12 made of a single layer film. In such a case, in step S2, the substrate 11 is placed in a constant vacuum atmosphere, the substrate 11 is heated to 700° C. or higher (preferably 800° C. or higher), and an electron using a vapor deposition material of Zr single crystal is used. Zr is evaporated by the beam evaporation method. At this time, the evaporated Zr is formed as a Zr film on the upper surface 11a as the main surface of the (100) surface of the substrate 11 heated to 700° C. or higher. The film thickness of the Zr film is, for example, preferably 0.2 nm to 30 nm, more preferably 0.2 nm to 5 nm.

When forming the alignment film 12 as a laminated film, next, Zr is evaporated by an electron beam evaporation method using an evaporation material of Zr single crystal, and the evaporated Zr is heated to 700° C. or higher on the substrate 11 Zr. By reacting with oxygen on the film, a ZrO ₂ film is formed.

When forming the orientation film 12 of a laminated film, then, by an evaporation method using an electron beam using an evaporation material Y was evaporated to Y, ZrO ₂ film on the substrate 11 which vaporized Y is heated above 700 ° C. By reacting with oxygen above, a Y ₂ O ₃ film is formed.

In this way, after the film formation of the ZrO ₂ film and the Y ₂ O ₃ film was repeated N times (N is an integer of 1 or more), the ZrO ₂ film was formed on the Y ₂ O ₃ film by the same method as described above. Form a film. Thereby, the ZrO ₂ film and the Y ₂ O ₂ film are alternately laminated, and the alignment film 12 having a vertically symmetrical sandwich structure in which the Y ₂ O ₃ film is sandwiched between the ZrO ₂ films from above and below is formed. Even if a Yttria Stabilized Zirconia (YSZ) film, which is a very hard and brittle material with a Young's modulus of 522 GPa, is formed at the joint between the ZrO ₂ film and the Y ₂ O ₃ film by thermal diffusion, it is vertically symmetrical. With the sandwich structure of No. 2, warpage due to stress of the YSZ film can be avoided.

Next, as shown in FIG. 10, a permanent magnet film as the first electrode 13 is formed on the alignment film 12 (step S3). Hereinafter, a method of forming the permanent magnet film by using the sputtering method will be described as an example, but the permanent magnet film can be formed by using various methods such as an electron beam evaporation method.

In step S3, a permanent magnet film is formed on the alignment film 12 by, for example, a sputtering method. At this time, the temperature of the substrate 11 at the time of film formation may be set to be equal to or higher than the lower limit value of the temperature range in which the formed permanent magnet film is crystallized, and the crystallized permanent magnet film may be directly formed. Alternatively, the temperature of the substrate 11 during film formation is set to be lower than the lower limit value of the temperature range in which the formed permanent magnet film is crystallized, and after the permanent magnet film is formed, the formed permanent magnet film is crystallized. The substrate 11 may be heat-treated at a temperature equal to or higher than the lower limit of the temperature range to crystallize the permanent magnet film.

When the temperature of the substrate 11 during film formation is set to the lower limit value of the temperature range in which the permanent magnet film is crystallized or higher, the substrate 11 is in a vacuum or an inert gas atmosphere so that the permanent magnet film is not oxidized. It is desirable to be placed inside. Further, the heat treatment time for crystallizing the formed permanent magnet film varies depending on the temperature of the substrate 11 at the time of heat treatment, that is, the heat treatment temperature. For example, when the heat treatment temperature is 650° C., 0.2 It is preferable to perform heat treatment for about 2 hours.

As the permanent magnet film, a permanent magnet film containing a rare earth element, that is, a permanent magnet film made of a rare earth magnet can be used. Alternatively, as the permanent magnet film, a permanent magnet film other than the rare earth magnet can be used.

Preferably, as a permanent magnet film made of a rare earth magnet, when R is a rare earth element, R—Fe—B based rare earth magnets such as R ₂ Fe ₁₄ B, RCo ₅ and R ₂ (Co, Fe, Cu, Zr). ) R-Co based rare earth magnet, such as _17, as well _as permanent including R _{2 Fe} 17 _{N 3} and _RFe 7 _{N x RFe-N-based} rare earth magnet, one or more rare earth magnets selected from the group consisting of such as A magnet film can be used. As a result, the residual magnetization perpendicular to the surface of the permanent magnet film can be increased as compared with the case where a permanent magnet film other than the rare earth magnet is used.

Since the R-Fe-B rare earth magnet is likely to become amorphous, the substrate temperature during film formation is controlled within the range of 300°C to 800°C, or after the film formation is set to 400°C to 800°C. Crystallization is desirable by heat treatment.

When the permanent magnet film contains R ₂ Fe ₁₄ B, the permanent magnet film preferably has a tetragonal crystal structure and is (001) oriented. The (001)-oriented R ₂ Fe ₁₄ B is likely to be a perpendicular magnetization film having a magnetization perpendicular to the surface of the first electrode 13, so that the residual magnetization of the first electrode 13 can be further increased.

When the permanent magnet film comprises RCo ₅ , the permanent magnet film preferably has a hexagonal crystal structure and is (11-20) oriented. The (11-20)-oriented RCo ₅ tends to be a magnetized film having a magnetization parallel to the surface of the permanent magnet film, but the magnetization perpendicular to the surface of the permanent magnet film also becomes large to some extent, so that the residual magnetization of the permanent magnet film is increased. Can be further increased.

When the permanent magnet film contains R ₂ (Co, Fe, Cu, Zr) ₁₇ , the permanent magnet film preferably has a hexagonal crystal structure and is (11-20) oriented. The (11-20) oriented R ₂ (Co, Fe, Cu, Zr) ₁₇ is likely to be a magnetic film having a magnetization parallel to the surface of the permanent magnet film, but the magnetization perpendicular to the surface of the permanent magnet film is also to some extent. Since it becomes larger, the residual magnetization of the permanent magnet film can be further increased.

On the other hand, as the permanent magnet film other than the rare-earth magnet, Ni magnet, Al-Ni-Co-based magnets such as Al-Ni-Co _alloy, Fe 3 Pt, FePt magnet such as FePt and FePt _3, Fe-Cr- A permanent magnet film made of one or more selected from the group consisting of Co-based magnets, Sr ferrite magnets, and Co-Fe-B-based magnets can be used.

When the permanent magnet film contains Ni, as described above, the permanent magnet film preferably has a cubic crystal structure and is (100) oriented. With Ni having a cubic crystal structure, remanent magnetization along the [100] direction is obtained, so that the remanent magnetization of the permanent magnet film can be further increased.

The method of heat-treating the substrate 11 when forming the permanent magnet film is arbitrary, and the substrate 11 may be heat-treated directly or indirectly by, for example, a sheath heater or an infrared lamp heater. When the substrate 11 is heat-treated after forming the permanent magnet film, it is desirable to heat-treat the substrate 11 in a vacuum atmosphere or an inert gas atmosphere so as not to oxidize the permanent magnet film. The heat treatment time for performing this heat treatment varies depending on the heat treatment temperature during the heat treatment, but for example, when the heat treatment temperature is 650° C., it is preferable to perform the heat treatment for about 0.2 to 2 hours.

Even if the targets used to form the permanent magnet film have the same composition, the composition of the permanent magnet film can be changed depending on the lattice constant of the orientation film 12 in the in-plane direction and the film forming conditions of the permanent magnet film. Therefore, it is possible to change the symmetry and the orientation direction of the crystal of the permanent magnet film along with the change of the composition.

Therefore, when the permanent magnet film contains R ₂ Fe ₁₄ B, the permanent magnet film contains tetragonal (001) oriented R ₂ Fe ₁₄ B instead of tetragonal (001) oriented R ₂ Fe ₁₄ B. You can also Alternatively, if the permanent magnet film comprises RCo ₅ or R ₂ (Co,Fe,Cu,Zr) ₁₇ , the permanent magnet film may be hexagonal (11-20) oriented RCo ₅ or R ₂ (Co,Fe,Cu). , Zr) ₁₇ may be included instead of hexagonal (0001) oriented RCo ₅ or R ₂ (Co, Fe, Cu, Zr) ₁₇ .

When the direction in which the permanent magnet film is easily magnetized is perpendicular to the surface of the permanent magnet film, a perpendicular magnetized film is easily obtained, and the direction in which the permanent magnet film is easily magnetized is the surface of the permanent magnet film. If it is parallel to, an in-plane magnetized film can be easily obtained. Therefore, the magnetization directions of the permanent magnet film can be aligned, and the magnitude of the magnetization of the permanent magnet film can be easily increased.

Next, as shown in FIG. 11, a film-shaped piezoelectric body 14 as a piezoelectric film is formed on the first electrode 13 (step S4). Below, the method of forming the film-shaped piezoelectric body 14 using a coating method is illustrated and demonstrated.

In this step S4, the content of lead on the first electrode 13 is smaller than the content of lead in the amorphous PZT film having the stoichiometric composition or the amorphous PZT film having the stoichiometric composition. An amorphous PZT film containing is formed. Next, the amorphous PZT film is heat-treated in a pressurized oxygen atmosphere to crystallize the amorphous PZT film, thereby forming the film-shaped piezoelectric body 14 containing PZT on the first electrode 13. When the content of lead in the amorphous PZT film having the stoichiometric composition is 100 atomic %, the content of lead less than the content of lead in the amorphous PZT film having the stoichiometric composition is , Preferably 80 to 95 atom %.

The method of forming the amorphous PZT film will be described below.

First, a sol-gel solution for forming an amorphous PZT film is prepared. As the sol-gel solution for forming an amorphous PZT film, an E1 solution containing butanol as a solvent and having a lead content of 70 to 90% deficient and a concentration of 10% by weight can be prepared.

To this E1 solution, an alkaline alcohol having an amino group such as dimethylaminoethanol is added at a volume ratio of E1 solution:dimethylaminoethanol=7:3. As a result, pH=12 and an E1 solution exhibiting strong alkalinity can be obtained.

Next, an amorphous PZT film is formed by the spin coating method using the E1 solution. The substrate 11 is held by a rotatably provided substrate holding part included in the spin coater, and a predetermined amount of the E1 solution is applied to the surface of the first electrode 13 and then first rotated at 800 rpm for 5 seconds. After rotating at 1500 rpm for 10 seconds, the E1 solution is applied by gradually increasing the rotation speed to 3000 rpm in 10 seconds. Next, the substrate 11 coated with the E1 solution is left on the hot plate whose temperature is controlled at 150° C. for 5 minutes, left on the hot plate whose temperature is controlled at 300° C. for 10 minutes, and then cooled to room temperature. .. By repeating this 5 times, an amorphous PZT film having a film thickness of 200 nm, for example, can be formed on the first electrode 13.

Next, the amorphous PZT film is heat-treated in a pressurized oxygen atmosphere. As a result, the film-shaped piezoelectric body 14 in which the amorphous PZT film is crystallized is formed on the first electrode 13.

Even when the E1 solution has the same composition, the composition of the film-shaped piezoelectric body 14 should be changed according to the lattice constant in the in-plane direction of the permanent magnet film (first electrode 13) and the film forming conditions of the permanent magnet film. Therefore, the symmetry and the orientation direction of the crystal of the film-shaped piezoelectric body 14 can be changed in accordance with the change of the composition. For example, an amorphous PZT film, the composition formula PbZr _x Ti _1-x O 3 as the Zr / Ti represented by (0 <x <1), 58/42 (x = 0.58), 52/48 ( In either case of x=0.52) or 42/58 (x=0.42), the formed film-shaped piezoelectric body 14 has a composition that originally has a rhombohedral crystal as Zr/Ti. It has 55/45, but has a tetragonal crystal structure and can be (001) oriented.

In the above example, the method of forming the film-shaped piezoelectric body 14 by using the coating method has been described as an example, but the method of forming the film-shaped piezoelectric body 14 is not limited to the coating method. Therefore, the film-shaped piezoelectric body 14 may be formed by using the sputtering method.

When the film-shaped piezoelectric body 14 is formed by using the sputtering method, even if the sputtering target has the same composition, the film-shaped piezoelectric body 14 is formed depending on the lattice constant in the in-plane direction of the permanent magnet film and the film forming conditions of the permanent magnet film. The composition can be changed, and the symmetry and the orientation direction of the crystal of the film-shaped piezoelectric body 14 can be changed with the change of the composition. For example, the sputtering target, as Zr / Ti represented by the composition formula _{PbZr x Ti 1-x O 3} (0 <x <1), 58/42 (x = 0.58), 52/48 (x = 0 .52) and 42/58 (x=0.42), the formed film-shaped piezoelectric body 14 is a composition which originally has a rhombohedral crystal as Zr/Ti. However, it has a tetragonal crystal structure and can be (001) oriented.

In this way, the piezoelectric element 10 shown in FIG. 3 is formed. Note that the second electrode 15 may be formed on the film-shaped piezoelectric body 14 after forming the film-shaped piezoelectric body 14.

As described above with reference to FIG. 6, the matching between the lattice constant of ZrO _{2 and} the lattice constant of Si is good. Therefore, the alignment film 12 comprising ZrO _2, the substrate 11 comprising silicon single crystals, can be epitaxially grown on the principal surface made of (100) plane, the alignment film 12 comprising ZrO _2, comprising a silicon single crystal The (100) plane can be oriented on the (100) plane of the substrate 11, and the crystallinity of the alignment film 12 can be improved.

Further, as described using FIG. 6 described above, the matching between the lattice constant of Ni and the lattice constant of ZrO ₂ is good. Therefore, the permanent magnet film containing Ni can be epitaxially grown on the orientation film 12 containing ZrO _2, and the permanent magnet film containing Ni can be grown on the (100) plane of the orientation film 12 containing ZrO ₂ by (100 ) It can be oriented and the crystallinity of the permanent magnet film can be improved.

Further, as described with reference to FIG. 6 described above, the matching between the lattice constant of PZT and the lattice constant of Ni is good. Therefore, the film-shaped piezoelectric body 14 containing PZT can be epitaxially grown on the permanent magnet film containing Ni, and the film-shaped piezoelectric body 14 containing PZT can be grown on the (100) plane of the permanent magnet film containing Ni. (100) orientation can be achieved, and the crystallinity of the film-shaped piezoelectric body 14 can be improved.

<Modification of First Embodiment>
In the first embodiment, the film-shaped piezoelectric body 14 is directly formed on the permanent magnet film as the first electrode. However, the film-shaped piezoelectric body 14 may be formed on the permanent magnet film via the conductive film 13a. Such an example will be described as a modified example of the first embodiment.

FIG. 12 is a cross-sectional view of a piezoelectric element of a modified example of the first embodiment. As shown in FIG. 12, the piezoelectric element 10a of this modification includes a substrate 11, an alignment film 12, a first electrode 13, a conductive film 13a, and a film-shaped piezoelectric body (piezoelectric film) 14. ..

The substrate 11 is made of a silicon substrate. The alignment film 12 is epitaxially grown on the substrate 11 and contains zirconium and oxygen. The details of the alignment directions of the substrate 11 and the alignment film 12 can be the same as in the first embodiment.

The first electrode 13 is epitaxially grown on the alignment film 12. As with the first embodiment, a permanent magnet film containing a rare earth element, that is, a permanent magnet film made of a rare earth magnet can be used as the first electrode 13. Alternatively, as the permanent magnet film, a permanent magnet film other than the rare earth magnet can be used.

In FIG. 12, the case where the first electrode 13 contains an Al—Ni—Co alloy will be described as an example. Also at this time, similarly to the first embodiment, the first electrode 13 preferably has a cubic crystal structure and is (100) oriented. In the Al—Ni—Co alloy having the cubic crystal structure, the remanent magnetization along the [100] direction is obtained, so that the remanent magnetization of the first electrode 13 can be further increased.

Here, the diffusion coefficient of Al in the Al-Ni-Co alloy is high. Therefore, Al in the Al—Ni—Co alloy may diffuse into the alignment film 12 containing ZrO ₂ depending on the film forming conditions when forming the first electrode 13 containing the Al—Ni—Co alloy. Thus, the diffusion layer 12a containing alumina-stabilized zirconia (AlZ) is formed on the upper portion of the alignment film 12. As with YSZ, ASZ is more likely to have a cubic (100) orientation than ZrO ₂ . Therefore, when the diffusion layer 12a is formed, the first electrode 13 containing the Al—Ni—Co alloy is more likely to be cubic (100) oriented than when the diffusion layer 12a is not formed.

In addition, in the case other than the case where the first electrode 13 includes the Al—Ni—Co alloy, the same as in the first embodiment can be performed including the orientation direction and the like.

The conductive film 13a is epitaxially grown on the first electrode 13. As the conductive film 13a, a conductive film 13a containing one or more conductors selected from the group consisting of a conductive oxide having a perovskite structure such as strontium ruthenate (SrRuO ₃ ) and a metal such as Pt is used. You can

When the conductive film 13a contains SrRuO ₃ , the conductive film 13a preferably has a cubic or pseudo-cubic crystal structure and is (100) oriented. When the conductive film 13a contains Pt, the conductive film 13a preferably has a cubic crystal structure and is (100) oriented. On the conductive film 13a having a cubic crystal structure, the film-shaped piezoelectric body 14 containing PZT, for example, can be easily epitaxially grown. Therefore, the piezoelectric constant of the film-shaped piezoelectric body 14 can be further increased.

The film-shaped piezoelectric body 14 is epitaxially grown on the conductive film 13a. That is, the film-shaped piezoelectric body 14 is formed on the first electrode 13 via the conductive film 13a. The film-shaped piezoelectric body 14 can be the same as in the first embodiment. Note that, as in the first embodiment, the second electrode 15 may be formed on the film-shaped piezoelectric body 14.

According to this modification, the electric resistance of the lower electrode (first electrode) of the film piezoelectric body 14 can be reduced, and the voltage applied to the film piezoelectric body 14 drops from the desired voltage. Can be prevented or suppressed. When a conductive film containing SrRuO ₃ is used as the conductive film 13a, a different phase is deposited at the interface between the film-shaped piezoelectric body 14 and the lower electrode of the film-shaped piezoelectric body 14 to deteriorate the piezoelectric characteristics. This can be prevented or suppressed.

13 and 14 are cross-sectional views of the piezoelectric element of the modification of the first embodiment during the manufacturing process.

In the manufacturing process of the piezoelectric element of the present modified example, the processes (steps S1 and S2) described with reference to FIGS. 8 and 9 in the first embodiment are performed to form the alignment film 12, and then, as shown in FIG. As shown, the first electrode 13 is formed on the alignment film 12 by, for example, a sputtering method. Here, when the first electrode 13 containing, for example, an Al—Ni—Co alloy is formed as the first electrode 13, Al in the Al—Ni—Co alloy diffuses into the alignment film 12 containing ZrO _2. By doing so, the diffusion layer 12a containing ASZ is formed in the upper layer portion of the alignment film 12.

Next, as shown in FIG. 14, a conductive film 13a is formed on the first electrode 13 by, for example, a sputtering method. As the conductive film 13a, for example, a conductive film 13a containing one or more conductors selected from the group consisting of a conductive oxide having a perovskite structure such as SrRuO ₃ and a metal such as Pt can be formed.

Next, a process similar to the process (step S4) described with reference to FIG. 11 in the first embodiment is performed to form the film-shaped piezoelectric body 14 on the conductive film 13a as shown in FIG. .. In this way, the piezoelectric element 10a is formed. Note that the second electrode 15 may be formed on the film-shaped piezoelectric body 14 as in the first embodiment.

[Second Embodiment]
In the piezoelectric element of the first embodiment, the permanent magnet film is formed between the alignment film and the piezoelectric film. However, a conductive film may be formed between the alignment film and the piezoelectric film, and the permanent magnet film may be formed on the piezoelectric film. Such an example will be described as a second embodiment. The description of the same parts as those in the first embodiment will be omitted in the second embodiment.

<Piezoelectric element having a film-shaped piezoelectric body>
FIG. 15 is a sectional view of the piezoelectric element of the second embodiment.

As shown in FIG. 15, the piezoelectric element 10b according to the second embodiment includes a substrate 11, an alignment film 12, a conductive film 13b (also referred to as a first conductive film), and a film-shaped piezoelectric body (piezoelectric film). 14 and a permanent magnet film 15a.

The substrate 11 is made of a silicon substrate. The alignment film 12 is epitaxially grown on the substrate 11 and contains zirconium and oxygen. The details of the alignment directions of the substrate 11 and the alignment film 12 can be the same as in the first embodiment.

The conductive film 13b is epitaxially grown on the alignment film 12. As the conductive film 13b, a conductive film 13b including one or more conductors selected from the group consisting of a conductive oxide having a perovskite structure such as SrRuO ₃ and a metal such as Pt can be used.

When the conductive film 13b contains SrRuO ₃ , the conductive film 13b preferably has a cubic or pseudo-cubic crystal structure and is (100) oriented. When the conductive film 13b contains Pt, the conductive film 13b preferably has a cubic crystal structure and is (100) oriented. On the conductive film 13b having a cubic crystal structure, for example, the film-shaped piezoelectric body 14 containing PZT can be easily epitaxially grown. Therefore, the piezoelectric constant of the film-shaped piezoelectric body 14 can be further increased.

The film-shaped piezoelectric body 14 is epitaxially grown on the conductive film 13b. Details such as the orientation direction of the film-shaped piezoelectric body 14 can be the same as those in the first embodiment.

The permanent magnet film 15 a is epitaxially grown on the film-shaped piezoelectric body 14. As the permanent magnet film 15a, as with the first electrode 13 of the first embodiment, a permanent magnet film containing a rare earth element, that is, a permanent magnet film made of a rare earth magnet can be used. Alternatively, as the permanent magnet film, a permanent magnet film other than the rare earth magnet can be used. Further, details such as the orientation direction of the permanent magnet film 15a can be the same as those of the first electrode 13 of the first embodiment.

In the second embodiment as well, as in the first embodiment, the film-shaped piezoelectric body 14 and the permanent magnet film 15a are epitaxially grown. As a result, the piezoelectric constant of the film-shaped piezoelectric body 14 can be increased as compared with the case where the film-shaped piezoelectric body 14 is not epitaxially grown, and the permanent magnet film 15a of the permanent magnet film 15a is formed as compared with the case where the permanent magnet film 15a is not epitaxially grown. The remanent magnetization can be increased. Then, the piezoelectric constant of the film-shaped piezoelectric body 14 can be increased.

On the other hand, in the second embodiment, unlike the first embodiment, the conductive film 13b is formed between the alignment film 12 and the film-shaped piezoelectric body 14. In the first embodiment, depending on the materials of the alignment film 12, the first electrode 13, the film-shaped piezoelectric body 14, and the second electrode 15, it may be easier to epitaxially grow by changing the stacking order. Alternatively, in the first embodiment, depending on the material of the first electrode 13, in order to prevent the deterioration of the first electrode 13, for example, after the film-shaped piezoelectric body 14 containing PZT is heat-treated, the permanent magnet film is formed. It may be better to form it.

In such a case, each layer can be easily epitaxially grown by sequentially stacking the alignment film 12, the conductive film 13b, the film-shaped piezoelectric body 14 and the permanent magnet film 15a as in the second embodiment. .. Alternatively, as in the second embodiment, the film-shaped piezoelectric body 14 is heat-treated and then the permanent magnet film 15a is formed, so that the deterioration of the permanent magnet film 15a can be prevented.

<Method of Manufacturing Piezoelectric Element Having Membrane Piezoelectric Body>
16 and 17 are cross-sectional views of the piezoelectric element of the second embodiment during the manufacturing process.

In the manufacturing process of the piezoelectric element of the second embodiment, after the steps (step S1 and step S2) described with reference to FIGS. 8 and 9 in the first embodiment are performed to form the alignment film 12, As shown in FIG. 16, a conductive film 13b is formed on the alignment film 12 by, for example, a sputtering method. As the conductive film 13b, for example, the conductive film 13b containing one or more conductors selected from the group consisting of a conductive oxide having a perovskite structure such as SrRuO ₃ and a metal such as Pt can be formed.

Next, a process similar to the process (step S4) described with reference to FIG. 11 in the first embodiment is performed, and as shown in FIG. 17, a film-shaped piezoelectric body (piezoelectric film) is formed on the conductive film 13b. 14 is formed.

Next, a step similar to the step (step S3) described with reference to FIG. 10 in the first embodiment is performed, and as shown in FIG. The electrode 13 is formed. In this way, the piezoelectric element 10b is formed.

Although the PZT film is used as the piezoelectric film in the first embodiment and its modification, and in the second embodiment, a piezoelectric film other than the PZT film may be used.

[Third Embodiment]
In the piezoelectric element of each of the first and second embodiments, it takes a long time to form a film if the film-shaped piezoelectric body is formed to have a large film thickness. That is, since the sol-gel method or the sputtering method is used as the film-forming method of the film-shaped piezoelectric body, it takes a longer time to form the film than the bulk-shaped piezoelectric body. Therefore, in the third embodiment, a method and an apparatus capable of forming a thick film piezoelectric material in a short film forming time will be described in detail.

FIG. 18 is a cross-sectional view schematically showing a sputtering device according to one aspect of the present invention. This sputtering apparatus has a chamber 51, and a holding portion 53 that holds a substrate 52 is arranged in the chamber 51. A heater (not shown) that heats the substrate 52 to a predetermined temperature may be arranged in the holding portion 53.

The chamber 51, the substrate 52 and the holding portion 53 are grounded. A target holding unit 55 that holds a sputtering target 54 is arranged in the chamber 51. The sputtering target 54 held by the target holding unit 55 is located so as to face the substrate 52 held by the holding unit 53.

The sputtering target 54 is a sputtering target including an insulator with a specific resistance of 1×10 ⁷ Ω·cm or more, and the insulator is preferably an oxide. Specifically, the insulator is a substance containing a substance having a perovskite structure represented by the general formula ABO ₃ . Here, A is selected from Al, Y, Li, Na, K, Rb, Pb, Cs, La, Sr, Cr, Ag, Ca, Pr, Nd, Ba, Bi, F and lanthanum series elements of the periodic table. Comprising at least one element selected from the group consisting of: B is Al, Ga, In, Nb, Sn, Ti, Zr, Ru, Rh, Pd, Re, Os, Ir, Pt, U, Co, Fe, Ni, Mn, Cr, Cu, Mg, V. , At least one element selected from the group consisting of Nb, Ta, Mo and W. Alternatively, the insulator is a substance including a ferroelectric crystal having a structure in which bismuth oxide and perovskite structure blocks are alternately laminated, that is, a bismuth layered structure. The perovskite structure block includes at least one element L selected from Li, Na, K, Ca, Sr, Ba, Y, Bi, Pb and rare earth elements, and Ti, Zr, Hf, V, Nb, Ta, W, It is preferable to be composed of at least one element R selected from Mo, Mn, Fe, Si and Ge, and oxygen.

However, the sputtering target 54 in the third embodiment and _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ, a, b, c, d, e and [delta] is Formula 1 below Formula 7 is satisfied. _Also referred to as _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ the PZT.
0≦δ≦1 Equation 1
1.00≦a+b≦1.35 Formula 2
0≦b≦0.08 Equation 3
1.00≦c+d+e≦1.1...Equation 4
0.4≦c≦0.7 Equation 5
0.3≦d≦0.6 Formula 6
0≦e≦0.1 Formula 7

The reason why δ includes a value larger than 0 in the above formula 1 is that it includes an oxygen-deficient perovskite structure. However, all components of the sputtering target 54 may have an oxygen deficient perovskite structure, but the sputtering target 54 may partially include an oxygen deficient perovskite structure. The details of the oxygen-deficient perovskite structure will be described later.

Further, the sputtering apparatus has an output supply mechanism 56, and this output supply mechanism 56 is a high frequency power supply with a pulse function. The output supply mechanism 56 is electrically connected to the matching unit 62, and the matching unit 62 is electrically connected to the target holding unit 55. That is, the output supply mechanism 56 provides a high frequency output (RF output) having a frequency of 10 kHz or more and 30 MHz or less to the sputtering target 54 via the matching unit 62 and the target holding unit 55 in a cycle of 1/20 ms or more and 1/3 ms or less. It is supplied in a pulse shape with a DUTY ratio of 25% or more and 90% or less (at a frequency of 3 kHz or more and 20 kHz or less). In the third embodiment, the output supply mechanism 56 supplies the high frequency output to the sputtering target 54 via the target holding unit 55. However, the output supply mechanism 56 directly supplies the high frequency output to the sputtering target 54. May be supplied.

The DUTY ratio is the ratio of the period in which the high frequency output is applied to the target holding unit 55 during one cycle. For example, in the case of a DUTY ratio of 25%, 25% of one cycle is a period in which a high frequency output is applied to the target holding unit 55 (high frequency output ON period), and 75% of one cycle is the target holding period. The period when the high frequency output is not applied to the portion 55 (the period when the high frequency output is off) is set. Specifically, for example, in the case of a DUTY ratio of 25% at a cycle of 1/20 ms (frequency of 20 kHz), a period of 1/80 ms, which is 25% of 1/20 ms (one cycle), is a high frequency output ON period. The period of 3/80 ms, which is 75% of /20 ms (one cycle), is the high frequency output off period.

Further, for example, FIG. 19 shows a case of a DUTY ratio of 100 S/T%, in which a period of 100 S/T% of one cycle becomes a high frequency output ON period and a remaining period of 100 N/T% of one cycle becomes. The high frequency output is off.

In addition, in the third embodiment, the pulse shape when the output supply mechanism 56 supplies the high frequency output to the target holding unit 55 in a pulse shape has a period of 1/20 ms or more and 1/3 ms or less (3 kHz or more and 20 kHz or less). 25% or more and 90% or less, but it is preferable that the pulse shape has a DUTY ratio of 25% or more and 90% or less in a cycle of 1/15 ms or more and 1/5 ms or less.

By performing pulse sputtering in the above range, a new sputtering phenomenon occurs by the number of new RF plasmas generated one after another, the film formation rate is dramatically improved, and the plasma OFF is completely stopped. However, the crystal continues to grow mainly in the migration phenomenon.

The reason for setting the DUTY ratio to 25% or more is that if it is less than 25%, the crystal growth will be completely interrupted and the next crystal growth will not be well connected. The reason why the DUTY ratio is set to 90% or less is that if it exceeds 90%, the film forming speed drops to almost the same level as a continuous wave.

Further, the sputtering apparatus has a _VDC controller 63 that controls the voltage _VDC , which is a DC component generated in the sputtering target 54 when the high frequency output is being supplied by the output supply mechanism 56, to −200V or more and −80V or less. .. The _VDC controller 63 has a _VDC sensor and is electrically connected to the output supply mechanism 56.

Further, the specific resistance of the surface of the sputtering target 54 after the high frequency output is supplied by the output supply mechanism 56 may change with respect to the specific resistance of the surface of a new sputtering target, but it is 1×10 ⁹ Ω·cm. It is preferably 1×10 ¹² Ω·cm or less.

Further, the sputtering apparatus has a first gas introduction source 57 that introduces a rare gas into the chamber 51, and a vacuum exhaust mechanism 59 such as a vacuum pump that evacuates the interior of the chamber 51. The sputtering device also has a second gas introduction source 58 for introducing O ₂ gas into the chamber.

The rare gas introduced into the chamber 51 by the first gas introduction source 57 may be Ar gas, and the O ₂ gas and the first gas introduction source 57 introduced by the second gas introduction source 58 during film formation. It is preferable that the sputtering apparatus has a flow rate control unit (not shown) that controls so that the ratio with the Ar gas introduced by the method satisfies Expression 8 below.
0.1≦O ₂ gas/Ar gas≦0.3 Formula 8

Further, the sputtering apparatus may have a pressure control unit that controls the pressure in the chamber during film formation to be 0.1 Pa or more and 2 Pa or less.

The sputtering apparatus also includes a magnet 60 that applies a magnetic field to the sputtering target 54, and a rotation mechanism 61 that rotates the magnet 60 at a speed of 20 rpm or more and 120 rpm or less.

Next, a method for forming an insulating film on a substrate using the sputtering apparatus shown in FIG. 18 will be described. As the substrate here, various substrates can be used and include those in which a thin film is formed on the substrate, but the following substrate is used as an example in the third embodiment.

A ZrO ₂ film is formed on a (100)-oriented Si substrate at a temperature of 550° C. or lower (preferably 500° C.) by a vapor deposition method. This ZrO ₂ film is (100) oriented. In this specification, the orientation of (100) and the orientation of (200) are substantially the same. Then, a lower electrode is formed on the ZrO ₂ film. The lower electrode is formed of an electrode film made of metal or oxide. As the electrode film made of metal, for example, a Pt film or an Ir film is used. As the electrode film made of an oxide, for example, a Sr(Ti _1-x Ru _x )O ₃ film is used, and x satisfies the following formula 9.
0.01≦x≦0.4 Equation 9

In the third embodiment, a Pt film formed by epitaxial growth is formed as a lower electrode on the ZrO ₂ film by sputtering at a temperature of 550° C. or lower (preferably 400° C.). This Pt film is (200) oriented.

In the third embodiment, the substrate as described above is used, but instead of the Si substrate, a single crystal substrate such as Si single crystal or sapphire single crystal, a single crystal substrate having a metal oxide film formed on the surface, a surface A substrate on which a polysilicon film or a silicide film is formed may be used.

Next, the above substrate is held by the holding unit 53. Then, Ar gas is introduced into the chamber 51 by the first gas introduction source 57, and O ₂ gas is introduced by the second gas introduction source 58. At this time, the flow rate control unit may control so that the ratio of O ₂ gas and Ar gas satisfies the following formula 10.
0.1≦O ₂ gas/Ar gas≦0.3 Formula 10

Further, the chamber 51 is evacuated by the vacuum evacuation mechanism 59 to reduce the pressure in the chamber 51 to a predetermined pressure (for example, a pressure of 0.1 Pa or more and 2 Pa or less).

After that, a high frequency output is provided on the substrate 52 by the output supply mechanism 56 via the matching unit 62 and the target holding unit 55 to the sputtering target 54 containing an insulator having a specific resistance of 1×10 ⁷ Ω·cm or more. Supply. This high-frequency output has a pulse shape with a frequency of 10 kHz or more and 30 MHz or less and a DUTY ratio of 25% or more and 90% or less at a cycle of 1/20 ms or more and 1/3 ms or less. Thereby, an insulating film is formed on the substrate 52.

When supplying a high frequency output to the sputtering target 54 and forming an insulating film, it is preferable to apply a magnetic field to the sputtering target 54 by rotating the magnet 60 by the rotating mechanism 61 at a speed of 20 rpm or more and 120 rpm or less.

Further, it is preferable that the voltage _VDC which is a DC component generated in the sputtering target 54 when the high frequency output is supplied to the sputtering target 54 is controlled by the _VDC controller 63 to be −200 V or more and −80 V or less.

Further, it is preferable to control the specific resistance of the surface of the sputtering target 54 after supplying the high frequency output to the sputtering target 54 to 1×10 ⁹ Ω·cm or more and 1×10 ¹² Ω·cm or less.

According to the third embodiment, a high-frequency output of 10 kHz or more and 30 MHz or less is applied to a sputtering target including an insulator having a specific resistance of 1×10 ⁷ Ω·cm or more at a cycle of 1/20 ms or more and 1/3 ms or less. It is supplied in a pulse form with a duty ratio of 25% or more and 90% or less. Since the high-frequency output is supplied in a pulsed manner in this way, even if the charge is accumulated in the sputtering target containing the insulator, the accumulated charge is released when the high-frequency output is not being supplied (when the high-frequency output is off). As a result, it is possible to prevent the sputtering target from being damaged. Therefore, the amount of power applied to the sputtering target can be increased and the film formation rate can be increased.

In particular, when the sputtering target 54 is a substance containing a substance having a perovskite structure represented by the general formula ABO ₃ or a substance containing a ferroelectric crystal having a bismuth layer structure, the surface resistance of the sputtering target 54 during film formation. Can vary greatly. For this reason, as described above, by supplying a high-frequency output in a pulsed manner and making it difficult for electric charges to accumulate in the sputtering target 54, it is possible to suppress fluctuations in the surface resistance of the sputtering target 54.

a, b, c, d, using the e and [delta] satisfy the equations 1 to 7 below _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ sputtering target 54 of the above formed piezoelectric film formed on a substrate by film method _is a _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film. It is preferable that a, b, c, d, e and δ satisfy the following expressions 1 to 7.
0≦δ≦1 Equation 1
1.00≦a+b≦1.35 Formula 2
0≦b≦0.08 Equation 3
1.00≦c+d+e≦1.1...Equation 4
0.4≦c≦0.7 Equation 5
0.3≦d≦0.6 Formula 6
0≦e≦0.1 Formula 7

The (Pb _a La _b )(Zr _c Ti _d Nb _e )O _3-δ film has a relative dielectric constant εr of 100 or more and 600 or less (preferably 100 or more and 400 or less) and a film thickness of 3 V or more and 15 V or less. may have at least one of the coercive voltage and 20 [mu] C / cm ² or more 50 .mu.C / cm ² or less of residual polarization value per 1 [mu] m. _{Further, (Pb a La b) (} Zr c Ti d Nb e) O 3-δ film has a film thickness of at least 5 [mu] m, preferably 10μm or more, more preferably 15μm or more, more preferably 20μm or more membrane It is good to have a thickness. _Further, it _is preferable is _(Pb a _La b) the Curie temperature of the _{(Zr c Ti d Nb e)} O 3-δ film, 250 ° C. or higher 420 ° C. or less (preferably not more than 400 ° C. 300 ° C. or higher).

The _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film may be formed on the electrode, for example Pt film or the like, the _{(Pb a La b) (Zr} c Ti d Nb e ) When the crystallinity of the O _3-δ film is evaluated by XRD (X-Ray Diffraction), the peak value of (002) of the XRD is higher than the peak value of (200) of the XRD of the electrode. This _is because it is _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film thickness of the film is 5μm or more.

Further, according to the third embodiment, the high frequency output is applied to the sputtering target made of (Pb _a La _b )(Zr _c Ti _d Nb _e )O _3-δ , and the DUTY ratio of the above is output at the above cycle. By supplying in a pulsed manner, the film formation rate at the time of forming the (Pb _a La _b )(Zr _c Ti _d Nb _e )O _3-δ film on the substrate is 1 nm/sec or more and 2.5 nm/sec or less. Can be improved.

Next, the oxygen-deficient perovskite structure will be described in detail with reference to FIGS.

The oxygen-deficient perovskite structure can be classified as follows when expressed by a general formula. The following classifications are based on the crystal structures that actually exist. The perovskite structure is represented by ABO _3-δ or A _n B _n O _3n-1 .

The left views of FIGS. 20 to 23 are schematic views showing various crystal structures containing oxygen deficiency of ABO _3-δ . The right views of FIGS. 20 to 23 are schematic views of the oxygen deficient structure on the ab plane, in which the C′ layer and the D′ layer are C and D layers, respectively, which are mirror images of the ab plane. FIG. 3 is a schematic diagram showing a state in which the phase is shifted.

FIG. 20 is a schematic diagram of an oxygen-deficient perovskite structure when δ=0.125 or n=8.0. FIG. 21 is a schematic diagram of an oxygen-deficient perovskite structure when δ=0.25 or n=4.0. FIG. 22 is a schematic diagram of an oxygen-deficient perovskite structure when δ=0.5 or n=2.0. FIG. 23 is a schematic diagram of an oxygen-deficient perovskite structure when δ=1.0 or n=1.0.

One of the perovskite derivative structures is an oxygen-deficient ordered (oxygen-deficient) perovskite structure. When the B-site transition metal is expensive and unstable, or oxygen is deficient due to control of the sample preparation atmosphere. When oxygen is deficient, the BO ₆ octahedron changes into a BO ₅ tetragonal pyramid, a BO ₄ tetrahedron, and the like. In ABO _3-δ in which oxygen is slightly deficient, oxygen is deficient at random sites while maintaining the basic structure, but when the oxygen deficiency amount δ becomes large, oxygen deficiency is regularly arranged in many cases.

The coordination structure varies greatly depending on the oxygen deficiency state. The BO ₆ (B: B site ion, O: oxygen ion) octahedron has an octahedral structure without oxygen deficiency. If B-site ion pentacoordinate, becomes BO ₅ square pyramid structure, having two structures in the case of four-coordinate, BO ₄ tetrahedral structure, BO ₄ plane (oxygen completely deficient).

Note that the above description of the oxygen-deficient perovskite structure applies to all substances related to the perovskite structure described in this specification.

[Fourth Embodiment]
In the piezoelectric element of each of the first and second embodiments, it takes a long time to form a film if the film-shaped piezoelectric body is formed to have a large film thickness. Therefore, in the third embodiment, a method of forming a thick film piezoelectric material in a short film forming time and a film piezoelectric material formed by the method will be described in detail.

24 to 26 are views for explaining a method of manufacturing a piezoelectric element having a film-shaped piezoelectric body according to an aspect of the present invention.

As shown in the sectional view of FIG. 24 (A), in the third embodiment and the same method, the ZrO ₂ film 102 is formed on a Si substrate 101, a first of Pt film on the ZrO ₂ film 102 The electrode 103 is formed.

Then, in the same manner as in the third embodiment, a film thickness of 5 μm or more (preferably 10 μm or more, more preferably 15 μm or more, still more preferably 20 μm or more) is formed on the first electrode 103 as a film-like piezoelectric body by a sputtering method. ) to form a first _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 104. It is preferable that a, b, c, d, e and δ satisfy the following expressions 1 to 7.
0≦δ≦1 Equation 1
1.00≦a+b≦1.35 Formula 2
0≦b≦0.08 Equation 3
1.00≦c+d+e≦1.1...Equation 4
0.4≦c≦0.7 Equation 5
0.3≦d≦0.6 Formula 6
0≦e≦0.1 Formula 7

Next, as shown in the cross-sectional view of FIG. _24B , for adhesion (Pb _a La _b )(Pb _a La _b )(Zr _c Ti _d Nb _e )O _3-δ film 104 on the first (Pb _a Lab)(Zr _c Ti _d Nb _e )O _3-δ film. The Zr _c Ti _d Nb _e )O _3-δ film 105 is formed by a sol-gel method and pre-baked. Adhesive of this time _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 105 is amorphous. It is preferable that a, b, c, d, e and δ satisfy the above expressions 1 to 7.

After that, as shown in the cross-sectional view of FIG. 24C, the Si substrate 101 is turned upside down. Then, as shown in the cross-sectional view of FIG. 24D, the Si substrate 101 is removed from the ZrO ₂ film 102. Even when the Si substrate 101 is completely removed, the first _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film thickness of 104 or more 5 [mu] m (preferably 10μm or more, more preferably 15μm As described above, more preferably 20 μm or more), the film can be self-supporting.

Next, as shown in the plan view of FIG. 25A and the cross-sectional view of FIG. 25B, the first electrode 103 and the ZrO ₂ film 102 are processed by a photolithography technique and an etching technique, so that the first on top _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 104 is formed a first electrode 103a, the second electrode 103b and the third electrode 103c. The first electrode 103a to the third electrode 103c serve as upper electrodes.

Thereafter, as shown in FIG. 25 (A), the first _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 104 and adhesive _{(Pb a La b) (Zr} c Ti d cutting the nb _{e) O 3-δ} film 105. Thus, the first electrode 103a, a first _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 104 and adhesive _{(Pb a La b) (Zr} c Ti d Nb e) O _A first laminated portion in which the _3-δ film 105 is laminated is formed. The second electrode 103b, a first _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 104 and adhesive _{(Pb a La b) (Zr} c Ti d Nb e) O 3 Forming a second laminated portion in which the _δ film 105 is laminated. The third electrode 103c, a first _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 104 and adhesive _{(Pb a La b) (Zr} c Ti d Nb e) O 3 Forming a third laminated portion in which the _δ film 105 is laminated. Note that although not shown in FIG. 25B, a fourth stacked portion and a fifth stacked portion are also formed. As shown in FIG. 26 to be described later, laminated part of the fourth, the fourth electrode 103d, a first _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 104 and adhesive (Pb _a La _b )(Zr _c Ti _d Nb _e )O _3-δ film 105 is laminated. The layered portion of the fifth, the fifth electrode 103e, a first _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 104 and adhesive _{(Pb a La b) (Zr} c The Ti _d Nb _e )O _3-δ film 105 is laminated.

Next, as shown in the sectional view of FIG. 26 (A), the first laminated portion first electrode 103a and the adhesive of the second laminated portion of _{(Pb a La b) (Zr} c Ti d Nb e) O _3-[delta] are superimposed on the film 105, the second laminated portion and the second electrode 103b and the adhesive of the third laminated portion of _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 105 preparative overlapped and overlapping the third laminated portion third electrode 103c and adhesive of the fourth laminated portion of _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 105.

Then, while applying a load between the adhesive of the first laminated portion and _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 105 fourth fourth electrode 103d of the laminate Heat treatment is applied. Thus, the first laminated portion first _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 104 and the first electrode 103a, respectively and adhesive of the second laminated portion (Pb _a La _b) with paste _{(Zr c Ti d Nb e)} O 3-δ film 105, the second laminated portion first _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ with paste film 104 and the second electrode 103b, respectively and adhesive of the third laminated portion _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 105, the third laminated portion first 1 of _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 104 and the third respectively the electrode 103c and the adhesive of the fourth laminated portion _{(Pb a La b) (Zr} c Ti d Nb with paste _{e) O 3-δ} film 105, the first to fourth multilayer portions for each of bonding the _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 105 is crystallized ( FIG. 26A). The temperature of the heat treatment at this time may is at a temperature adhesive _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 105 is crystallized.

Next, as shown in the cross-sectional view of FIG. 26B, the electrode 106 is formed on the side surface of the second electrode 103b and the fourth electrode 103d, and the first electrode 103a, the third electrode 103c, and the fifth electrode 103c are formed. The electrode 107 is formed on the side surface of the electrode 103e. The electrode 106 is electrically connected to the second electrode 103b and the fourth electrode 103d, and the electrode 107 is electrically connected to the first electrode 103a, the third electrode 103c, and the fifth electrode 103e. In this way, the piezoelectric element can be manufactured. Note that in FIG. _{26B, the} (Pb _a La _b )(Zr _c Ti _d N _{b e} )O _3-δ film 105 was crystallized (Pb _a La _b )(Zr _{c Td} Nb _e )O. the _3-[delta] film, are shown integral with the first _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 104. The piezoelectric element corresponds to the piezoelectric element 354 shown in FIG.

Also in the fourth embodiment, the same effect as in the third embodiment can be obtained.

[Fifth Embodiment]
In the fifth embodiment, a method of forming a thick film piezoelectric material in a short film forming time and a film piezoelectric material formed by the method will be described in detail.

27 to 29 are views for explaining a method for manufacturing a piezoelectric element having a film-shaped piezoelectric body according to an aspect of the present invention.

As shown in the sectional view of a plan view and FIG. 27 in FIG. 27 (A) (B), in the third embodiment the same method, to form a ZrO ₂ film 102 on the Si substrate 101, the ZrO ₂ film 102 A first electrode 103 made of a Pt film is formed on top.

Then, in the same manner as in the third embodiment, a film thickness of 5 μm or more (preferably 10 μm or more, more preferably 15 μm or more, still more preferably as a film-shaped piezoelectric body is formed on the first electrode 103 made of a Pt film by a sputtering method. forms a first _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 104 of 20μm or more). It is preferable that a, b, c, d, e and δ satisfy the following expressions 1 to 7.
0≦δ≦1 Equation 1
1.00≦a+b≦1.35 Formula 2
0≦b≦0.08 Equation 3
1.00≦c+d+e≦1.1...Equation 4
0.4≦c≦0.7 Equation 5
0.3≦d≦0.6 Formula 6
0≦e≦0.1 Formula 7

Then, by the first _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 104 a Pt film as an electrode film is formed on, is etched the Pt film, the first _{(Pb a La b) (Zr} c Ti d Nb e) a first electrode 111a on _{O 3-[delta]} film 104 to form the second electrode 111b and the third electrode 111c (FIG. 27 (a), ( See B)).

Next, as shown in the sectional view of the plan view and FIG. 28 (B) of FIG. 28 (A), the first _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 104, the the adhesive _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 112 was formed by a sol-gel method on the first electrode 111a~ third electrode 111c, presintered. Adhesive of this time _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 112 is amorphous. It is preferable that a, b, c, d, e and δ satisfy the above expressions 1 to 7.

After that, as shown in the cross-sectional view of FIG. 29A, the ZrO ₂ film 122 is formed on the Si substrate 121 by the same method as in the third embodiment, and the ZrO ₂ film 122 is used as an electrode film. The Pt film 123 is formed. Then, in the same manner as in the third embodiment, _a second (Pb _a ) film having a thickness of 5 μm or more (preferably 10 μm or more, more preferably 15 μm or more, still more preferably 20 μm or more) is formed on the Pt film 123 by a sputtering method. La _b )(Zr _c Ti _d Nb _e )O _3-δ film 124 is formed. It is preferable that a, b, c, d, e and δ satisfy the above expressions 1 to 7.

Then, superimposed adhesive _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 112 and the second _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 124 match. Then, heat treatment is performed while applying a load between the Si substrate 101 and the Si substrate 121. Thus, an adhesive _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 112 and the second _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 124 paste. The temperature of the heat treatment at this time may is at a temperature at which the adhesive _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 112 is crystallized.

Next, as shown in the cross-sectional view of FIG. 29B, the Si substrate 101 and the Si substrate 121 are removed. Then, as shown in the sectional view of FIG. 29 (C), the Pt film 123 and the ZrO ₂ film 122 is processed by a photolithography technique and an etching technique, the second _{(Pb a La b) (Zr} c Ti d The first electrode 123a, the second electrode 123b, and the third electrode 123c are formed over the Nb _e )O _3-δ film 124. Further, the first electrode 103 and the ZrO ₂ film 102 is processed by a photolithography technique and an etching technique, the first _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 104 below The first electrode 103a, the second electrode 103b, and the third electrode 103c are formed.

Thereafter, the first _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 104, adhesive _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 112 and cutting the second _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 124. Then, by performing the step shown in FIG. 26B, a piezoelectric element can be manufactured. This piezoelectric element corresponds to the piezoelectric element 354 shown in FIG.

Also in the fifth embodiment, the same effect as in the third embodiment can be obtained.

[Sixth Embodiment]
In the sixth embodiment, a method of forming a thick film piezoelectric material in a short film forming time and a film piezoelectric material formed by the method will be described in detail.

30 to 32 are views for explaining a method of manufacturing a piezoelectric element having a film-shaped piezoelectric body according to an aspect of the present invention. 30 to 32 are cross-sectional views.

As shown in FIG. 30 (A), after the up to the step shown in FIG. 27 in the fifth embodiment, the first _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 104 A film thickness of 5 μm or more (preferably 10 μm or more, more preferably 15 μm) on the first electrode 111a, the second electrode 111b, and the third electrode 111c by the sputtering method in the same manner as in the third embodiment. As described above, more preferably 20 μm or more) of (Pb _a La _b )(Zr _c Ti _d Nb _e )O _3-δ film 132 is formed. It is preferable that a, b, c, d, e and δ satisfy the following expressions 1 to 7.
0≦δ≦1 Equation 1
1.00≦a+b≦1.35 Formula 2
0≦b≦0.08 Equation 3
1.00≦c+d+e≦1.1...Equation 4
0.4≦c≦0.7 Equation 5
0.3≦d≦0.6 Formula 6
0≦e≦0.1 Formula 7

Then, in the third embodiment the same method, the ZrO ₂ film 122 is formed on the Si substrate 121, to form a Pt film 123 as a first electrode on the ZrO ₂ film 122. Then, in the same manner as in the third embodiment, a film-shaped piezoelectric material having a film thickness of 5 μm or more (preferably 10 μm or more, more preferably 15 μm or more, still more preferably 20 μm or more) is formed on the Pt film 123 by a sputtering method. forming a second _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 124. It is preferable that a, b, c, d, e and δ satisfy the above expressions 1 to 7.

_Then, superposed _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 132 and the second _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 124. Then, heat treatment is performed while applying a load between the Si substrate 101 and the Si substrate 121. Attaching _Thus, bonding the _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 132 and the second _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 124 ..

Next, as shown in FIG. 30B, the Si substrate 121 is removed.

Then, as shown in FIG. 30 (C), the Pt film 123 and the ZrO ₂ film 122 is processed by a photolithography technique and an etching technique, the second _{(Pb a La b) (Zr} c Ti d Nb e) A first electrode 123a, a second electrode 123b, and a third electrode 123c are formed on the O _3-δ film 124.

Then, a second _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 124, adhesive on the first electrode 123a~ third electrode _{123c (Pb a La b) (} Zr the _{c Ti d Nb e) O 3} -δ film 133 was formed by a sol-gel method, calcination. Adhesive of this time _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 133 is amorphous. It is preferable that a, b, c, d, e and δ satisfy the above expressions 1 to 7.

Thereafter, as shown in FIG. 31 (A), forming the ZrO ₂ film 142, Pt film _143, a _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 144 are sequentially on the Si substrate 141 _and form a _{(Pb a La b) (Zr} c Ti d Nb e) a first electrode 145a on the _{O 3-[delta]} film 144, the second electrode 145b and the third electrode 145c. Then, on the first electrode 145a~ third electrode 145c, is formed by sputtering _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 146. It is preferable that a, b, c, d, e and δ satisfy the above expressions 1 to 7.

Then, a ZrO ₂ film 152 is formed on the Si substrate 151, and a Pt film 153 as an electrode film is formed on the ZrO ₂ film 152. Then formed by sputtering on the Pt film 153 of _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 154. It is preferable that a, b, c, d, e and δ satisfy the above expressions 1 to 7.

_Then, superposed _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 146 and _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 154. Then, heat treatment is performed while applying a load between the Si substrate 141 and the Si substrate 151. _Thus, pasting _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 146 and _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 154.

Next, as shown in FIGS. 31B and 31C, the Si substrate 151, the ZrO ₂ film 152, and the Pt film 153 are removed.

Thereafter, as shown in FIG. 32 (A), shown in Figure 30 for bonding shown in _{(C) (Pb a La b} ) (Zr c Ti d Nb e) O 3-δ film 133 and FIG. 31 (C) _{(Pb a La b) (Zr} c Ti d Nb e) superimposing the _{O 3-[delta]} film 154. Then, as shown in FIG. 32B, heat treatment is performed while applying a load between the Si substrate 101 and the Si substrate 141. Thus, pasting an adhesive _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 133 and _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 154. The temperature of the heat treatment at this time may is at a temperature at which the adhesive _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 133 is crystallized. Further, in FIG. 32 (B), adhesive _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 133 is crystallized _{(Pb a La b) (Zr} c Ti d Nb e) O the _{3-[delta] film,} is shown as _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 133a.

Next, as shown in FIG. 32C, the Si substrate 141 and the ZrO ₂ film 142 are removed. Then is processed by photolithography and etching a Pt film _{143, (Pb a La b)} (Zr c Ti d Nb e) O 3-δ the first electrode 143a on the film 144, the second electrode 143b and the third electrode 143c are formed.

Thereafter, FIG. 32 (A), by repeating the steps (B), _(C), it is possible to increase the number of stacked _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film ..

Also in the sixth embodiment, the same effect as that of the third embodiment can be obtained. The piezoelectric element of the sixth embodiment corresponds to the piezoelectric element 354 shown in FIG.

[Seventh Embodiment]
In the seventh embodiment, a method of forming a thick film piezoelectric material in a short film forming time and a film piezoelectric material formed by the method will be described in detail.

33 to 36 are views for explaining a method for manufacturing a piezoelectric element having a film-shaped piezoelectric body according to an aspect of the present invention. 33 to 36 are cross-sectional views.

As shown in FIG. 33 (A), in the third embodiment and the same method, the ZrO ₂ film 162 is formed on a Si substrate 161, to form a Pt film 163 on the ZrO ₂ film 162. The Pt film 163 becomes the first layer _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ the first electrode of the membrane.

Then, in the same manner as in the third embodiment, a film piezoelectric material having a film thickness of 5 μm or more (preferably 10 μm or more, more preferably 15 μm or more, still more preferably 20 μm or more) is formed on the Pt film 163 by sputtering. forming a layer eyes _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 164. It is preferable that a, b, c, d, e and δ satisfy the following expressions 1 to 7.
0≦δ≦1 Equation 1
1.00≦a+b≦1.35 Formula 2
0≦b≦0.08 Equation 3
1.00≦c+d+e≦1.1...Equation 4
0.4≦c≦0.7 Equation 5
0.3≦d≦0.6 Formula 6
0≦e≦0.1 Formula 7

Next, as shown in FIG. 33 (B), 1-layer _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 164 on the 550 ° C. temperature below (preferably at a temperature of 400 ° C. ), a Pt film 165 is formed by epitaxial growth by sputtering. The Pt film 165 becomes the second layer _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ second electrode of the membrane.

Thereafter, as shown in FIG. 33C, a film thickness of 5 μm or more (preferably 10 μm or more, more preferably 15 μm or more, and further preferably, is formed on the Pt film 165 by a sputtering method in the same manner as in the third embodiment. forms a second layer of 20μm or _{more) (Pb a La b) (} Zr c Ti d Nb e) O 3-δ film 166. It is preferable that a, b, c, d, e and δ satisfy the above formulas 1 to 7.

Next, as shown in FIG. 33 (D), 2-layer _{(Pb a La b) (Zr} c Ti d Nb e) a Pt film 167 on the _{O 3-[delta]} film 166 similar to the Pt film 165 of the It is formed by the method. The Pt film 167 is three-layer _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ third membrane electrode.

Thereafter, by repeating the steps shown in process and FIG. 33 (D) shown in FIG. 33 (C), as shown in FIG. 34 (A), 3-layer on the Pt film 167 _(Pb a _La b) ₍ forming the _{Zr c Ti d Nb e) O} 3-δ film 168, Pt film 169,4-layer _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 170, Pt film 171. It is preferable that a, b, c, d, e and δ satisfy the above formulas 1 to 7. Pt film 169 becomes a fourth layer _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ fourth electrode for film, Pt film 171 becomes a fifth electrode. Then, the Si substrate 161 is removed from the ZrO ₂ film 162.

Next, ZrO ₂ film 162, Pt film 163,1-layer _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 164, Pt film 165,2-layer _(Pb a _La b) ₍ Zr _c Ti _d Nb _e )O _3-δ film 166, Pt film 167, third layer (Pb _a La _b )(Zr _c Ti _d Nb _e )O _3-δ film 168, Pt film 169, fourth layer (Pb _a La _b )O _3-δ film 168. _{pb a La b) (Zr c} Ti d Nb e) O 3-δ is cut to the required size of the multilayer film having a 170 and a Pt film 171 (not shown). As a result, a plurality of laminated parts shown in FIG. 34A are obtained.

Although the laminated film is cut after removing the Si substrate 161 in the seventh embodiment, the laminated film is cut before removing the Si substrate 161 and then the Si substrate is removed. Good.

Next, as shown in FIG. 34B, a photosensitive permanent resist film 172 is applied to the first side surface of the above laminated portion. Next, as shown in FIG. 35A, the photosensitive permanent resist film 172 is exposed and developed to form permanent resist films 172a and 172b on the first side surface of the laminated portion. As a result, the first side surface of the Pt film (fourth electrode) 169 of the laminated portion is covered with the permanent resist film 172a, and the first side surface of the Pt film (second electrode) 165 of the laminated portion is the permanent resist film. The first side surfaces of the Pt film (first electrode) 163, the Pt film (third electrode) 167, and the Pt film (fifth electrode) 171 of the stacked portion are covered with the film 172b and are exposed.

After that, as shown in FIG. 35B, the first side surface of the Pt film (first electrode) 163, the Pt film (third electrode) 167, and the Pt film (fifth electrode) 171 in the stacked portion. A Pt film (sixth electrode) 173 is formed on the permanent resist films 172a and 172b. As a result, the Pt film (sixth electrode) 173 is electrically connected to the Pt film (first electrode) 163, the Pt film (third electrode) 167, and the Pt film (fifth electrode) 171. ..

Next, as shown in FIG. 36(A), the laminated portion of FIG. 35(B) is arranged upside down, and a photosensitive permanent resist film 174 is applied to the second side surface of this laminated portion. Next, as shown in FIG. 36B, the photosensitive permanent resist film 174 is exposed and developed to form permanent resist films 174a, 174b, 174c on the second side surface of the laminated portion. As a result, the second side surface of the Pt film (first electrode) 163 of the laminated portion is covered with the permanent resist film 174a, and the second side surface of the Pt film (third electrode) 167 of the laminated portion is the permanent resist film. The second side surface of the Pt film (fifth electrode) 171 in the laminated portion is covered with the permanent resist film 174c. Further, the second side surfaces of the Pt film (second electrode) 165 and the Pt film (fourth electrode) 169 in the laminated portion are exposed.

Thereafter, as shown in FIG. 36C, the second side surfaces of the Pt film (second electrode) 165 and the Pt film (fourth electrode) 169 of the laminated portion and the permanent resist films 174a, 174b, 174c, respectively. A Pt film (seventh electrode) 175 is formed thereon. As a result, the Pt film (seventh electrode) 175 is electrically connected to the Pt film (second electrode) 165 and the Pt film (fourth electrode) 169, respectively. In this way, the piezoelectric element can be manufactured.

Also in the seventh embodiment, the same effect as that of the third embodiment can be obtained. The piezoelectric element of the seventh embodiment corresponds to the piezoelectric element 354 shown in FIG.

Incidentally, according to the seventh embodiment, ZrO ₂ film 162, Pt film 163,1 layer of the first electrode _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 164, the Pt film 165,2 layer of the second electrode _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 166, the Pt film 167,3 layer of the third electrode _(Pb a La _{b) (Zr c Ti d Nb} e) O 3-δ film 168, Pt film 169,4 layer of the fourth electrode _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 170 , The laminated portion having the Pt film 171 as the fifth electrode is used, but the present invention is not limited to this, and the following modifications can be made.

Pt film 163,1 layer of the at least a first electrode _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 164, the Pt film 165,2 layer of the second electrode (Pb It is also possible to use a laminated portion having _a La _b )(Zr _c Ti _d Nb _e )O _3−δ film 166 and a Pt film 167 as the third electrode. In that case, if the first side surface of the Pt film 163 serving as the first electrode and the first side surface of the Pt film 167 serving as the third electrode are electrically connected by the Pt film 173 serving as the sixth electrode. Good.

Further, Pt film 163,1 layer of the first electrode _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 164, Pt film 165,2 th layer as a second electrode ( _{Pb a La b) (Zr c} Ti d Nb e) O 3-δ film 166, Pt film 167,3 layer of the third electrode _{(Pb a La b) (Zr} c Ti d Nb e) O 3- It is also possible to use a laminated portion having the _δ film 168 and the Pt film 169 as the fourth electrode. In that case, the first side surface of the Pt film 163 serving as the first electrode and the first side surface of the Pt film 167 serving as the third electrode are electrically connected by the Pt film 173 serving as the sixth electrode. The second side surface of the Pt film 165 serving as the second electrode and the second side surface of the Pt film 169 serving as the fourth electrode may be electrically connected by the Pt film 175 serving as the seventh electrode.

The electrode of the further n-th layer on the Pt film 171 as a fifth electrode shown in FIG. _{34 (A) (Pb a La} b) (Zr c Ti d Nb e) O 3-δ film and the (n + 3) May be repeatedly formed. In this case, n is an integer of 5 or more. For example, when n is 5, 6, 7, Pt film 163,1 layer of the first electrode _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 164, a second electrode Pt film 165,2 layer of _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 166, the Pt film 167,3 layer of the third electrode _{(Pb a} La b) _{(Zr c Ti d Nb e) O 3} -δ film 168, Pt film 169,4 layer of the fourth electrode _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 170, the fifth Pt film 171 as an electrode, fifth layer (Pb _a La _b )(Zr _c Ti _d Nb _e )O _3-δ film, eighth electrode, sixth layer (Pb _a La _b ) (Zr _c Ti _d Nb) _{e) O 3-δ} film and the ninth electrode, the seventh layer _{(Pb a La b) (Zr} c Ti d Nb e) a laminated portion having a _{O 3-[delta]} film and tenth electrode. In that case, the first side surface of the Pt film 163 as the first electrode, the first side surface of the Pt film 167 as the third electrode, the first side surface of the Pt film 171 as the fifth electrode, and the ninth side surface. The first side surface of the electrode may be electrically connected by the Pt film 173 serving as the sixth electrode. Further, the second side surface of the Pt film 165 serving as the second electrode, the second side surface of the Pt film 169 serving as the fourth electrode, the second side surface of the eighth electrode, and the second side surface of the tenth electrode. The side surface may be electrically connected by the Pt film 175 serving as the seventh electrode.

In addition, you may implement combining the 1st Embodiment-7th Embodiment mentioned above suitably.

(Example 1)
The method for producing the sample of Example 1 is as follows.

On a (100)-oriented Si single crystal substrate with a natural oxide film on the surface, first only Zr under the conditions on the left side of (1) in Table 1 (film formation time of 10 sec, evaporation source of Zr) Under the conditions shown on the right side of (1) in Table 1, simultaneously with Zr vapor deposition, vapor deposition was performed for 170 sec while supplying O ₂ (oxygen) toward the substrate. Thus, a ZrO ₂ (100)/Si(100) substrate having a total film thickness of 15 nm was formed by the vacuum evaporation method.

Subsequently, only Fe was vapor-deposited under the condition (2) in Table 1, and then only Pt was vapor-deposited under the condition (3) in Table 1. _Thus, to produce a Fe _{0.5 -Pt 0.5} / ZrO ₂ structure.

FIG. 37 is an XRD (X-Ray Diffraction) pattern of the sample of Example 1. As can be seen from FIG. 37, an Fe _0.5 -Pt _0.5 alloy known as a magnetic metal having a thickness of 150 nm and oriented in (100) and (001) could be formed.

(Example 2)
The method for producing the sample of Example 2 is as follows.

On a (100)-oriented Si single crystal substrate with a natural oxide film on the surface, first, only Zr under the conditions on the left side of (1) in Table 2 (film formation time of 10 sec, evaporation source of Zr) Under the conditions on the right side of (1) in Table 2, simultaneously with Zr vapor deposition, vapor deposition was performed for 170 sec while supplying O ₂ (oxygen) toward the substrate. Thus, a ZrO ₂ (100)/Si(100) substrate having a total film thickness of 15 nm was formed by the vacuum evaporation method.

Then, Fe-Pt was vapor-deposited under the condition (2) in Table 2 using the Fe-Pt bath mixed in a weight ratio of 1:1 (25 g:25 g). _Thus, to produce a Fe _{0.96 -Pt} 0.04 / ZrO ₂ structure.

38 and 39 are XRD patterns of the sample of Example 2. As shown in FIGS. 38 and 39, a strong single peak of Fe _0.96 -Pt _0.04 was obtained, and the peak appeared at a position very close to that of Fe (200). The lattice constant of Fe _0.96- Pt _0.04 was 2.8 Å, which was very close to the lattice constant of Fe atoms of 2.88 Å.

Next, when the film thickness and composition of the sample of Example 2 were analyzed by XRF (X-Ray-Fluorescence) (AZX400 manufactured by Rigaku Corporation), the results shown in Table 3 were obtained. From this, it was found that the sample obtained in Example 2 was the Fe _0.96 Pt _0.04 alloy (200).

(Examples 3 to 5)
By using the sputtering apparatus shown in FIG. 18 to form a PZT film on a substrate under the sputtering conditions shown in Table 4, a sample of Example 3 (present invention 5 μm), a sample of Example 4 (present invention 10 μm), A sample of Example 5 (the present invention 20 μm) and a sample of Comparative Example 1 (conventional example) were prepared. The substrate used here was a Si substrate on which a ZrO ₂ film was formed by vapor deposition, and a Pt film formed by epitaxial growth on the ZrO ₂ film as a lower electrode by sputtering.

The composition of the sputtering target and the composition of the sample when producing the samples of Examples 3 to 5 and Comparative Example 1 are as follows.

<Composition of sputtering target>
Example 3 (Invention 5 μm): Pb/Zr/Ti=130/58/42
Example 4 (Invention 10 μm): Pb/Zr/Ti=130/58/42
Example 5 (20 μm of the present invention): Pb/Zr/Ti=130/58/42
Comparative example 1 (conventional example): Pb/Zr/Ti=130/58/42

<Sample composition>
Example 3 (Invention 5 μm): Pb/Zr/Ti=109/55/45
Example 4 (Invention 10 μm): Pb/Zr/Ti=105/55/45
Example 5 (Invention 20 μm): Pb/Zr/Ti=102/55/45
Comparative example 1 (conventional example): Pb/Zr/Ti=98/55/45

The surface resistance value of the sputtering target before film formation and the surface resistance value of the sputtering target after film formation are probed using an insulation resistance measuring device (MODEL: ADC5450 (Ultra High Resistance Meter)) which is a ferroelectric measurement system. The distance was 5 mm and the measurement voltage was 10 V. The measurement results are as follows.

<Surface resistance value of sputtering target before film formation>
Center part of sputtering target: 2.03×10 ¹¹ Ω·cm
Between the central part and the outer peripheral part of the sputtering target: 2.10×10 ¹¹ Ω·cm
Outer periphery of sputtering target: 5.39×10 ¹⁰ Ω·cm

<Surface resistance value of sputtering target after film formation>
Center part of sputtering target: 4.95×10 ¹¹ Ω·cm
Between the central part and the outer peripheral part of the sputtering target: 1.45×10 ¹² Ω·cm
Outer part of sputtering target: 3.49×10 ¹¹ Ω·cm

FIG. 40(A) is an image obtained by observing the cross section of the sample of Example 3 with a FIB (Focused Ion Beam), and FIG. 40(B) is an image of observing the cross section of the sample of Example 4 with a FIB. The film thickness of the PZT film of Example 3 was 5.18 μm, and the film thickness of the PZT film of Example 4 was 9.99 μm. These film thicknesses are Tilt correction values. The reason why this Tilt correction is necessary is as follows. (1) When cutting is repeated with FIB, the observation image has a visual field shift. Correction is necessary because the cutting area deviates from the center of the SEM (Scanning Electron Microscope) image. (2) The FIB cutting surface is not perpendicular to the observation optical axis. Since the sloping surface is viewed, the vertical and horizontal scales in the image are different and correction is necessary. For the above reason, it is necessary to correct the Tilt angle and correct it with the actually measured length.

41 is an XRD chart of the PZT film of Example 3 and the PZT film of Example 4, and the crystallinity of the PZT film of Example 3 and the PZT film of Example 4 was evaluated by XRD (X-Ray Diffraction). It is a figure which shows a result. The (002) peak value of the XRD of the PZT film is higher than the (200) peak value of the XRD of the Pt film. This is because the thickness of the PZT film is 5 μm or more.

Wide area reciprocal lattice mapping was performed on each of the samples of Examples 3 to 5 and Comparative Example 1. An image of the reciprocal lattice map is shown in FIG.

The XRD data of this example uses a fully automatic horizontal multipurpose X-ray diffractometer SmartLab manufactured by Rigaku Corporation, and for wide area reciprocal lattice mapping, a hybrid multidimensional pixel detector HyPix-3000 is attached to the SmartLab for measurement. went.

FIG. 43 is a diagram for explaining reciprocal lattice vectors and reciprocal lattice points on the crystal lattice plane (hkl). FIG. 44 is a diagram illustrating vector notation of X-ray diffraction conditions.
・_Reciprocal lattice vector ( _ghkl )
Size: Reciprocal of d value of (hkl) plane Direction: Normal direction of (hkl) plane/reciprocal lattice mapping The spread of reciprocal lattice points in reciprocal space is measured.
Reciprocal lattice point: Tip of reciprocal lattice vector, condition for causing diffraction Scatter vector: K=k−k ₀
(Scattering vector K)=(reciprocal lattice vector g _hkl ).
-Reciprocal lattice map measurement The scattering vector K is scanned and the two-dimensional distribution of reciprocal lattice points is measured.
A reciprocal lattice simulation is performed in advance based on the crystal structure information and compared with the actually measured value. The reciprocal lattice map is plotted by the following q _x and q _z equations.

2θ was 10-120°, Ω was 10-90°, Χ was measured in four stages of 0°, 30°, 60° and 90°, and Φ was measured in two planes at 0° and 45°. Two measurements of Φ=0° (//Si110), Φ=45° (//Si100), and each sample Φ=0° and 45° were measured.

In the case of the conventional θ-2θ measurement, the substrate is fixed horizontally, and X-ray irradiation is performed (see FIG. 45A).

The θ-2θ measurement is performed while scanning the ω axis (rotational axis of the sample) and the χ axis (tilt operation axis). The φ axis (in-plane rotation axis) was measured at two points of 0° and 45°. After the θ-2θ/ω axis scanning measurement, q _z vs. The q _x plot is the reciprocal lattice mapping, and the reciprocal lattice mapping is performed at the same time while performing several steps of χ axis scanning, and all are overlaid on one surface to measure different components of the domain, and to know the superiority or inferiority of the true orientation degree. (See FIGS. 45B and 45C).

Using Rigaku's software SmartLab Guidance, the arrangement of reciprocal lattice points is simulated in advance based on the known PZT crystal structure information as shown in FIG. I went.

FIG. 47 shows the reciprocal lattice simulation result of the PZT single crystal.

48(A) and (B) are the results of reciprocal lattice map measurement of the samples of Example 3 (present invention 5 μm) and Example 4 (present invention 10 μm). As shown in these figures, it is found that the calculated values (x points) of the reciprocal lattice points of the PZT single crystal completely match, and that the PZT films of Example 3 and Example 4 are good single crystal films.

As shown in Table 4, in the conventional example, since a high frequency continuous wave was used without using a pulse, when the output was increased to 1800 W or more (10 W/cm ² or more), an arc was generated and plasma was abnormally discharged. As a result, the sputtering device stopped, and the output could not be increased above 1800W. On the other hand, in Example 3 (the present invention 5 μm), Example 4 (the present invention 10 μm) and Example 5 (the present invention 20 μm), a high frequency output of 13.56 MHz was applied to the sputtering target at a pulse frequency of 5 kHz (1/ Since it was supplied in a pulse shape with a DUTY ratio of 90% at a cycle of 5 ms, there was a time when plasma was not standing on the sputtering target when the high frequency output was in the off state, and as a result, the film thickness was thick in a short time. The PZT film could be easily formed.

49(A) is a diagram showing ferroelectric hysteresis curves of Example 3 (present invention 5 μm), Example 4 (present invention 10 μm) and Example 5 (present invention 20 μm), and FIG. 10] is a diagram showing piezoelectric butterfly curves of Examples 3 to 5. [FIG.

As shown in FIGS. 49A and 49B, it was confirmed that ferroelectricity and piezoelectricity proportional to the film thickness of the PZT film were obtained. In the sample of Example 5 having a film thickness of 20 μm, a very large coercive voltage Vc of 87 V was obtained. Moreover, when the Curie temperature Tc of the PZT film of Example 5 was measured, it was Tc=390° C.

50(A) is a diagram showing a ferroelectric hysteresis curve of Comparative Example 2 (K148), and FIG. 50(B) is a diagram showing a piezoelectric butterfly curve of Comparative Example 2 (K148). FIG. 51(A) is a diagram showing a ferroelectric hysteresis curve of Comparative Example 3 (K129), and FIG. 51(B) is a diagram showing a piezoelectric butterfly curve of Comparative Example 3 (K129).

Comparative example 2 (K148) and comparative example 3 (K129) are bulk piezoelectric elements manufactured by Reed Techno Co., Ltd. The piezoelectric element has a disk shape with a diameter of 8 mm and a thickness of about 0.5 mm (500 μm). As a piezoelectric element of Comparative Example 2 (K148) and Comparative Example 3 (K129), a hard system PZT (K148) generally used and a soft system PZT (K129) depending on the displacement amount were compared.

First, the Curie temperature (Tc) as the transition temperature of the catalog value, the piezoelectric constant d33 (pC/N), and the relative permittivity εr were as follows.
Tc of K129: 145°C
D129 of K129: 720
Εr of K129: 8100
Tc of K148: 280°C
D33 of K148: 530
Εr of K148: 2400

Unlike general K148, K129, which is concerned with piezoelectric displacement, has elements such as Ni and Nb added, and has a large relative permittivity of 8000 or more, and accordingly, a large piezoelectric displacement can be obtained, which is used for actuator applications. However, at the same time, Tc=145° C., which is extremely low, and the temperature characteristics are poor, so that the required locations are limited.

In the case of the general bulk K148, the butterfly shape is optimal for sensor applications (see FIG. 50(B)), but the coercive electric field Ec=11.42 kV/cm of the bulk K148 is compared with the embodiment of the present invention. Therefore, when converted per 20 μm, the coercive electric field Ec=11.42 kV/cm becomes 22.84 V/20 μm, which is a very low coercive voltage Vc=22.84 V. In the case of the actuator K129, the coercive electric field Ec=5.7 kV/cm is 11.4 V/20 μm, the coercive voltage Vc is even lower at 11.4 V, and Tc=145° C. is also low. There is a common problem in bulk that heat treatment such as reflow (generally around 280° C.) easily causes depolarization and loses piezoelectricity.

On the other hand, the sample of the PZT single crystal film of Example 5 (the present invention 20 μm) described above has a coercive voltage Vc of 87 V/20 μm. Further, since Tc is as high as 300° C. or higher, there is no fear of depolarization at all even when a reflow temperature during processing or a potential application such as static electricity occurs.

The PZT bulk laminate is formed by laminating the bulks of Comparative Examples 2 and 3 each having a thickness of about 20 μm, and the coercive voltage Vc per layer is about 25 V at the highest. In addition, in order to bring out a large piezoelectricity, the Curie temperature Tc as a transition temperature is often 200° C. or less because it contains a large amount of an additive. As a result, when the laminated body is completed, it is often depolarized and cannot perform piezoelectric operation at all. On the other hand, in the sample of Example 5 (the present invention 20 μm), the coercive voltage Vc was 87 V/20 μm, and Tc=390° C. (measured value), and depolarization did not occur at all.

Next, d33 evaluation of the PZT film of Example 5 (the present invention 20 μm) was performed. In detail, the characteristics were evaluated by applying a load of 300 g on the upper Pt of 2 mmφ for several seconds. It was a very large value of d33=1200 pC/N (see FIG. 52). A size about twice that of the bulk was easily obtained. Since Example 5 is pure PZT, it is highly possible that a value of 5 to 10 times will be obtained when the additive elements and the like are examined.

FIB-SEM cross-sectional images of the sample (20 μm-PZT film) of Example 5 are as shown in FIGS. 53(A) and (B). FIG. 53(B) is an enlarged image of FIG. 53(A).

According to FIG. 53, the columnar structure of the ordinary polycrystalline PZT film does not exist at all, and it is a very good single crystal. However, although a region that seems to be another orientation region was found in only a small portion, it is clear that it has an overwhelming piezoelectricity when considered as one layer of a normal PZT laminated bulk body, and it has a thickness of about 20 μm. Also, the overwhelming piezoelectric thick film that can be called a single crystal film was obtained.

According to the ferroelectric hysteresis curve of Example 4 (present invention 10 μm) shown in FIG. 49(A), the relative permittivity (εr), remanent polarization value (Pr), coercive voltage (Vc) and coercive electric field (Ec) were obtained. Is as follows. Further, when the Curie temperature (Tc) of the PZT film of Example 4 was measured, it was as follows.
Relative permittivity (εr) = approx. 200 @ 1kHz
Curie temperature (Tc)=408°C
Residual polarization value (Pr)=about 40 μC/cm ²
Coercive voltage (Vc)=44V
Coercive electric field (Ec)=44 kV/cm

According to the ferroelectric hysteresis curve of Comparative Example 2 (K148) shown in FIG. 50(A), the relative permittivity (εr), remanent polarization value (Pr), coercive voltage (Vc) and coercive electric field (Ec) are as follows. It is as follows. Further, the Curie temperature (Tc) of the PZT bulk of Comparative Example 2 was measured, and was as follows.
εr=2400
Tc=280°C
Pr=37.92 μC/cm ²
Ec=11.42 kV/cm
Vc=571V@0.5mm (11.42V@10μm)

According to the ferroelectric hysteresis curve of Comparative Example 3 (K129) shown in FIG. 51(A), the relative permittivity (εr), remanent polarization value (Pr), coercive voltage (Vc) and coercive electric field (Ec) are as follows. It is as follows. Further, when the Curie temperature (Tc) of the PZT bulk of Comparative Example 3 was measured, it was as follows.
εr=8100
Tc=145°C
Pr=29.76 μC/cm ²
Vc=275V@0.5mm (Vc=5.5V@10μm)
Ec=5.7 kV/cm

FIG. 54 is a diagram showing the results of measuring the temperature changes of the relative permittivity and the dielectric loss (tan δ) of the sample of Example 4 (the present invention 10 μm) while changing the frequencies to 100 k, 500 k and 1 MHz.

Specifically, an impedance analyzer (HP4192A manufactured by Agilent Technologies) is used to measure a 10 μm-PZT sample capacitor on a hot plate (MSA Factory, PH-210-600 type (50 to 600° C.)). The temperature change of the relative permittivity and the dielectric loss (tan δ) was measured while changing the frequency to 100 k, 500 k, and 1 MHz while heating at. Curie temperature (transition temperature): Tc=390° C., dielectric loss: tan δ=about 2-3%.

(Example 6)
FIG. 55 is a sectional view showing a sample of the sixth embodiment. The method for producing the sample of Example 6 is as follows.

A ZrO ₂ film 202 is formed on the Si substrate 201 by a vapor deposition method, and a Pt film 203 is formed on the ZrO ₂ film 202 by sputtering by epitaxial growth. Then, an SrRuO ₃ film, that is, an SRO film 204 is formed on the Pt film 203 by using the sputtering apparatus shown in FIG. 18 under the sputtering conditions shown in Table 5. The composition of the sputtering target at this time is Sr:Ru=1:1.15.

Next, using the sputtering apparatus shown in FIG. 18, a PZT film 205 having a film thickness of 1 μm is formed on the SRO film 204 under the sputtering conditions of Example 3 (present invention: 5 μm) shown in Table 4. However, since the film thickness of the PZT film 205 here is 1 μm, the film formation time of Example 3 (present invention 5 μm) shown in Table 4 is set to 720 s.

Then, a SrRuO ₃ film, that is, an SRO film 206 is formed on the PZT film 205. The film forming conditions at this time are the same as the above-described film forming conditions for the SRO film 204. Then, a Pt film 207, an SRO film 208, and a PZT film 209 having a film thickness of 1 μm are sequentially formed on the SRO film 206. At this time, the film forming conditions for the Pt film 207 are the same as the film forming conditions for the Pt film 203, the film forming conditions for the SRO film 208 are the same as the film forming conditions for the SRO film 204, and the PZT film 209. The film forming conditions of are the same as those of the PZT film 205 described above. In this way, the sample of Example 6 shown in FIG. 55 can be manufactured.

The results of evaluating the crystallinity of the sample of Example 6 by XRD are shown in FIGS. 56 and 57. 56 and 57 are XRD patterns of the sample of Example 6. 56 and 57 show different angle ranges. Further, in each of FIG. 56 and FIG. 57, (1) shows an XRD pattern before a layer above the first layer PZT (PZT film 205) is formed, and (2) shows the first layer PZT. 7 shows an XRD pattern after a layer above (PZT film 205) is formed.

The following can be seen from the XRD patterns of FIGS. 56 and 57.

Comparing the crystallinity of the first layer Pt electrode (Pt film 203) and the intermediate Pt electrode (Pt film 207), in the case of the intermediate Pt electrode, the half-value of the Pt (400) peak was compared to the first layer Pt electrode. It was found that the intermediate Pt electrode was also epitaxially grown although the width was slightly wide and slightly broad.

Next, comparing the crystallinity of the first layer PZT (PZT film 205) and the second layer PZT (PZT film 209), the PZT (004) peak of the second layer PZT is higher than that of the first layer PZT. Although the half-value width was slightly wide and slightly broad, it was similarly found that epitaxial growth including the intermediate Pt electrode was performed.

(Example 7)
FIG. 58 is an image of a cross section of the sample of Example 7 observed by FIB. The sample of Example 7 has the same sectional structure as that shown in FIG. The manufacturing method of Example 7 is as follows.

A ZrO ₂ film is formed on a Si substrate by a vapor deposition method, and a Pt film formed by epitaxial growth is formed on the ZrO ₂ film by sputtering. Then, using the sputtering apparatus shown in FIG. 18, a PZT film having a film thickness of 1 μm is formed on the Pt film under the sputtering conditions of Example 3 (present invention: 5 μm) shown in Table 4. However, since the film thickness of the PZT film here is 1 μm, the film forming time of Example 3 (present invention 5 μm) shown in Table 4 is set to 720 s.

Then, a Pt film and a PZT film having a film thickness of 1 μm are sequentially formed on the PZT film. At this time, the Pt film forming conditions are the same as the Pt film forming conditions, and the PZT film forming conditions are the same as the PZT film forming conditions. In this way, a sample of Example 7 having the same sectional structure as that shown in FIG. 33C can be manufactured.

In addition, it is also possible to combine the above-described first to seventh embodiments and Examples 1 to 7 with each other within a range of ordinary creativity of those skilled in the art.

Further, in the above embodiment, there is an embodiment in which a piezoelectric element including a substrate is described, but it is also possible to implement a piezoelectric element that does not include a substrate by removing the substrate after manufacturing the piezoelectric element. is there.

10, 10a, 10b Piezoelectric element 11 Substrate 11a Upper surface 12 Alignment film 12a Diffusion layer 13 First electrodes 13a, 13b Conductive film 14 Membrane piezoelectric body 15 Second electrode 15a Permanent magnet film 51 Chamber 52 Substrate 53 Holding part 54 Sputtering Target 55 Target holding unit 56 Output supply mechanism 57 First gas introduction source 58 Second gas introduction source 59 Vacuum exhaust mechanism 60 Magnet 61 Rotation mechanism 62 Matching device 63 VDC control unit 101, 121, 141, 151, 161 Si substrate 102, 122, 142, 152, 162 ZrO ₂ film 103, 103a, 111a, 123a, 143a, 145a First electrode 103b, 111b, 123b, 143b, 145b Second electrode 103c, 111c, 123c, 143c, 145c the third electrode 103d fourth electrode 103e fifth electrode 104 first _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 105,112,133 adhesive _(Pb a _La b) ₍ Zr _c Ti _d Nb _e )O _3-δ film 106, 107 electrodes 123, 143, 153, 163, 165, 167, 169 Pt film 124 second (Pb _a La _b ) (Zr _c Ti _d Nb _e )O _3-[delta] film _{132,133a (Pb a La b) (} Zr c Ti d Nb e) O 3-δ film _{144,146,154 (Pb a La b) (} Zr c Ti d Nb e) O 3-δ film 164 first layer _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 166 second layer _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 168 third layer _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 170 fourth layer _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film 171, 173, 175 Pt film 172 174 Photosensitive permanent resist films 172a, 172b, 174a, 174b, 174c Permanent resist film 201 Si substrate 202 ZrO ₂ film 203, 207 Pt film 204, 206, 208 SRO film 205, 209 PZT film 301 Rotor 302 Stator 303, 304 , 305, 306 Permanent magnet 351 Rotor 352 Stator 353 Shaft 354 Piezoelectric element 355 Electromagnet 355a Core 355b Insulated wire

Claims (14)

A motor having a rotor and a stator,
The rotor includes a ring-shaped rotor, a first N-pole permanent magnet, a first S-pole permanent magnet, a second N-pole permanent magnet, and a second N-pole permanent magnet arranged on the inner circumference of the rotor. And an S-pole permanent magnet,
The stator includes a ring-shaped stator, a plurality of piezoelectric elements and a plurality of electromagnets arranged along the stator,
The motor, wherein each of the plurality of piezoelectric elements has a piezoelectric body sandwiched between a first electrode and a second electrode. The motor according to claim 1,
The piezoelectric body may be a bulk piezoelectric body or a film piezoelectric body. The motor according to claim 2,
The first electrode is a first conductive film or a first ferromagnetic film,
The motor, wherein the second electrode is a second conductive film or a second ferromagnetic film. The motor according to claim 2 or 3,
Each of the plurality of piezoelectric elements includes a single crystal substrate, the first electrode oriented on the single crystal substrate, the film-shaped piezoelectric body disposed on the first electrode, and A second electrode arranged on the film-shaped piezoelectric body. The motor according to claim 4,
A motor having a first film disposed between the single crystal substrate and the first electrode and oriented on the single crystal substrate. The motor according to claim 5,
The single crystal substrate is a silicon substrate,
The motor, wherein the first film is a metal oxide film that is more easily oxidized than silicon. The motor according to claim 3,
The motor, wherein each of the first and second ferromagnetic films is a metal film. The motor according to claim 6,
The silicon substrate has a main surface composed of (100) planes,
The motor according to claim 1, wherein the first film has a cubic crystal structure and contains (100)-oriented zirconium oxide. The motor according to any one of claims 2 to 8,
The film-shaped piezoelectric body has a tetragonal crystal structure and includes (001)-oriented lead zirconate titanate. The motor according to any one of claims 2 to 8,
The film-shaped piezoelectric body has a rhombohedral crystal structure and includes (100) oriented lead zirconate titanate. The motor according to any one of claims 2 to 8,
The film-shaped piezoelectric body is a (Pb _a La _b )(Zr _c Ti _d Nb _e )O _3-δ film having a film thickness of 5 μm or more,
a, b, c, d, e and δ satisfy the following formulas 1 to 7,
Wherein _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film has a specific dielectric constant of 100 or more and 600 or less,
Wherein _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film, the coercive voltage and 20 [mu] C / cm ² or more 50 .mu.C / cm ² or less of residual polarization value of 15V per following thickness 1μm or 3V A motor having at least one.
0≦δ≦1 Equation 1
1.00≦a+b≦1.35 Formula 2
0≦b≦0.08 Equation 3
1.00≦c+d+e≦1.1...Equation 4
0.4≦c≦0.7 Equation 5
0.3≦d≦0.6 Formula 6
0≦e≦0.1 Formula 7 The motor according to claim 11,
The peak value of _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film XRD of (002) is higher than the peak value of (200) of XRD of the first electrode, the motor. The motor according to claim 12,
The motor, wherein the first electrode comprises a Pt film. The motor according to any one of claims 11 to 13,
The Curie temperature of _{(Pb a La b) (Zr} c Ti d Nb e) O 3-δ film is 250 ° C. or higher 420 ° C. or less, the motor.

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