JPH0645664A - Piezoelectric element and its manufacture - Google Patents

Abstract

PURPOSE:To achieve a more compact piezoelectric element by providing an electrode for a piezoelectric material having a vibration mode in the radial direction. CONSTITUTION:A resist pattern 2' which is obtained by forming a resist layer 2 with polymethylmethacrylate as a material on a substrate 1 and then performing lithography according to synchrotron radiation light has a structure where a plurality of cylindrical bodies are aligned on a base with a specific spacing. Then, a metal structure body 3 is deposited by electrical plating, a gate plate 4 where a number of holes are provided are placed on it and a piezoelectric slurry is allowed to flow to it, and then it is calcined, thus enabling a plurality of piezoelectric ceramic rod-shaped bodies 6 to be bundled on a gate plate 4 at a specific spacing. Thus, a resin 7 is allowed to flow from a part on it for hardening. However, a shape is predetermined so that the volume % of the piezoelectric ceramic is 30-50%, a gate plate 4 is eliminated, and then electrodes 9a and 9b are provided at both edges of a obtained compound piezoelectric material 8 and then polarization treatment is performed, thus achieving a piezoelectric element 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piezoelectric element and a method for manufacturing the same, and more particularly to a small piezoelectric element usable for underwater ultrasonic communication and a method for manufacturing the same.

[0002]

2. Description of the Related Art A piezoelectric element using a bulk material of piezoelectric ceramics such as lead zirconate titanate (PZT) has been widely used for transmitting and receiving ultrasonic waves in water. Composite piezoelectric materials combined with resins have also come to be used for piezoelectric elements.

This composite piezoelectric material is shown in FIG.
As shown in (a) and (b) respectively, a cylindrical rod 60a and a prismatic rod 60b made of piezoelectric ceramic are arranged and embedded in the resins 61a and 61b, respectively. . An element using this composite material can have higher sensitivity to ultrasonic waves than piezoelectric ceramics. Such materials are used for receiving elements such as sonar.

[0004]

On the other hand, the size of the piezoelectric material used for the transmitting / receiving element is determined according to the following equation, for example.

[0005]

[Equation 1]

In the above equation, N is a constant which varies depending on the material of the piezoelectric material and the vibration mode. Vibration modes include
As is already known, there are radial vibration, longitudinal vibration, longitudinal vibration, thickness vibration, thickness sliding vibration, and the like.

In the case of thickness vibration, the value of N is about 2800 for quartz, about 2000 for PZT, and about 800 for PVDF of piezoelectric resin. Looking at PZT, the value of N is about 2000 for radial vibration, but about 1400 for longitudinal vibration.

When a specific piezoelectric material is used in a specific vibration mode, N has a predetermined value, so that the length (1) in the vibration direction to be used is determined according to the frequency used, as shown in the above equation. . The length (1) in the vibration direction used in this way is N
Constrained by Therefore, even if an attempt is made to reduce the size of the element, it is difficult to downsize the element because of the N value given by the conventional material.

The present invention is directed to such a problem, and an object thereof is to provide a smaller piezoelectric element.

[0010]

A piezoelectric element according to the first invention is a piezoelectric element in which an electrode is provided on a piezoelectric material having a vibration mode in a radial direction. In this piezoelectric element, the piezoelectric material is one in which a plurality of rod-shaped bodies made of piezoelectric ceramics are dispersed and embedded in a polymer at a volume fraction of 30% to 50%.

In this specification, the term "piezoelectric ceramics" refers to ceramic materials that exhibit a piezoelectric effect. Piezoelectric ceramics include, for example, crystals of a perovskite structure such as barium titanate and lead zirconate-lead titanate-based solid solutions. For example, lead zirconate titanate (PZT) and lead lanthanum zirconate titanate are included. (PLZT) and the like are preferably used.

As the polymer according to the present invention, epoxy resin, polyethylene resin, urethane resin, or rubber such as silicon rubber, urethane rubber or butadiene rubber can be used.

In the first invention, the reason why the piezoelectric ceramics embedded in the polymer has a volume fraction of 30% to 50% is as follows.

With respect to the frequency N, if the Young's modulus is Y and the density is ρ, the following equation holds.

[0015]

[Equation 2]

For a composite material using a radial vibration mode, Young's modulus Y is given by the following equation.

[0017]

[Equation 3]

On the other hand, ρ is given by the following equation.

[0019]

[Equation 4]

With respect to the composite materials obtained by combining various resins with lead zirconate titanate (PZT) according to the above formula, the change of the frequency constant by changing the volume fraction of the resin and PZT was examined. The results are shown in Table 1.

[0021]

[Table 1]

It can be seen from Table 1 that in any case, a low frequency constant is obtained when the volume fraction of the piezoelectric ceramic is 30% to 50%, and the frequency constant becomes minimum when the volume fraction is 40%. . If the frequency constant is kept low in this way, the length (l) in the vibration direction to be used, that is, the size of the piezoelectric element can be reduced in accordance with Equation 1.

For example, when the volume fraction of the piezoelectric ceramic is around 40%, the frequency constant using the epoxy resin is about 1/2 that of the PZT bulk material. The frequency constant using rubber is about 1/80 of PZT, and the frequency constant using polyethylene resin is about 1/5. Such a reduction rate is directly reflected in the reduction rate of the size of the piezoelectric vibrator.

On the other hand, when the longitudinal vibration mode is used, the Young's modulus Y is given by the following equation.

[0025]

[Equation 5]

According to this equation, N is hardly reduced by changes in v _c and v _p . Therefore, in the longitudinal vibration mode, it is difficult to reduce the size of the device by changing the volume fraction of the material.

As described above, the element can be made smaller by setting the volume fraction of the piezoelectric ceramic in the composite piezoelectric material having the radial vibration mode to 30 to 50%.

On the other hand, since the composite piezoelectric material has a low piezoelectric constant, it may be inferior as a sounding body to the bulk material of piezoelectric ceramics. For example, the volume fraction of ceramics is
At about 20%, the piezoelectric constant of the composite material is about half that of piezoelectric ceramics.

If the volume fraction of the piezoelectric ceramics increases, the piezoelectric constant tends to decrease further.

On the other hand, even if the volume fraction of the same piezoelectric ceramic is small, the cross-sectional size of the rod-shaped body is made smaller, and a structure in which a larger number of small-diameter rod-shaped bodies are distributed in the resin is realized, and thus the piezoelectric material of the composite material The constant can be increased. It is considered that this is because the smaller the cross-sectional size (for example, the diameter) of the rod-shaped body, the more uniform the material distribution.

For example, when a material in which a cylindrical or fiber-shaped piezoelectric ceramic is embedded in a resin is used for an element, the diameter of the piezoelectric ceramic is conventionally 100 to 200 μm.
Although it was about m, in the present invention, the diameter of the piezoelectric ceramic is preferably about 10 to 50 μm, more preferably 10 μm or less. By thus reducing the diameter, it is possible to obtain an element having a high piezoelectric constant while being downsized.

In order to prepare a piezoelectric material in which a piezoelectric ceramic having a small diameter is embedded in a resin as described above and obtain a piezoelectric element using the same, the following manufacturing method is preferable.

That is, there is provided a method for manufacturing a piezoelectric element according to the second aspect of the present invention, which comprises forming a resist layer and then subjecting the resist layer to lithography by synchrotron radiation to form a resist pattern. A step of manufacturing a structure having a plurality of holes using the resist pattern as a prototype, and introducing a raw material of the piezoelectric ceramic into the holes of the structure to form a plurality of piezoelectric ceramic rods according to the shape of the holes. And a step of solidifying a plurality of rod-shaped bodies thus obtained with a resin, and a step of providing electrodes on the rod-shaped body solidified with a resin and performing a polarization treatment.

In the second invention, when a structure having a plurality of holes is manufactured using a resist pattern as a prototype,
The structure may be formed from the resist pattern itself, or a mold may be prepared using the resist pattern as a mold, and the structure may be formed using this mold.

The above structure can be formed of metal, plastic, or the like. The structure made of metal is
For example, it can be formed by depositing a metal in the resist pattern by electroplating or the like. In this case, the base material on which the resist pattern is formed is used as one electrode for electroplating.

When it is desired to obtain a plastic structure, first, a metal structure is formed by electroplating according to a resist pattern, and then the plastic structure can be formed using this metal structure as a template.

Further, the plastic structure can be adhered to a conductive material and electroformed to form a metal structure having the plastic structure as a mold.

Whichever method is used, a structure having a plurality of holes of a predetermined size (for example, 10 μm to 50 μmφ) is finally obtained. Then, the raw material of the piezoelectric ceramic is introduced into the holes of the structure. A piezoelectric ceramic slurry or the like can be used as the raw material.

After filling the holes with the raw material, the packing is taken out to obtain a structure conforming to the shape of the holes. Further, if the raw material is extruded from this hole, a rod-shaped body or fiber having the cross-sectional shape of this hole can be obtained. The structure, rod-shaped body, or fiber thus obtained can be made into a piezoelectric ceramic while maintaining its shape by, for example, firing.

If a plurality of piezoelectric ceramics thus obtained are dispersed or arrayed and the resin is poured into the resin to solidify it, the composite piezoelectric ceramics in which the piezoelectric ceramics are dispersed and embedded. The material is obtained. By providing electrodes on this composite piezoelectric material and subjecting it to polarization treatment, an element can be obtained in which a large number of piezoelectric ceramic rod-shaped bodies each having a small cross section are dispersed in a resin.

The method described above is particularly suitable for forming a small piezoelectric element having a high piezoelectric constant.

On the other hand, the structure having holes can also be formed by electric discharge machining. That is, according to the third invention, a further method of manufacturing a piezoelectric element is provided, which comprises a step of forming a mold having a plurality of holes by electrical discharge machining, and introducing a ceramic piezoelectric material into the holes of the mold. Forming a plurality of piezoelectric ceramic rods according to the shape of the holes, and a step of solidifying the plurality of rods with resin,
In this way, the rod-shaped body is solidified with the resin, the electrodes are provided, and the polarization process is performed.

Also in the third invention, the structure can be formed of metal, plastic or the like. EDM has high machining accuracy and is suitable for fine machining. By electrical discharge machining, it is possible to form a structure having a plurality of holes of 10 to 50 μmφ, for example.

As described above, if the raw material is filled into such holes and then the filling material is taken out, a structure conforming to the shape of the holes can be obtained. Further, if the raw material is extruded from this hole, a rod-shaped body or fiber having the cross-sectional shape of this hole can be obtained. The thus obtained material can be made into a piezoelectric ceramic while maintaining its shape by, for example, firing as described above.

Further, the piezoelectric element can be manufactured according to the fourth invention. A method of manufacturing a piezoelectric element according to a fourth aspect of the present invention includes a step of forming a resist layer, and then forming a resist pattern having a plurality of holes in the resist layer by using lithography with synchrotron radiation. Introducing ceramic raw materials,
A step of forming a plurality of piezoelectric ceramic rods according to the shape of the holes, a step of solidifying the plurality of rods with a resin, and a step of performing polarization treatment by providing electrodes on the rods solidified with a resin. Equipped with.

In the fourth invention, various methods can be used for the step of introducing the piezoelectric ceramic material into the holes of the resist pattern to form a plurality of piezoelectric ceramic rod-shaped bodies in accordance with the shape of the holes. . For example, as such a method, a resist pattern having a plurality of holes is immersed in an electrolytic solution obtained by pulverizing and dispersing a piezoelectric ceramic material, and the piezoelectric ceramic material is deposited in the holes of the resist pattern by electrodeposition. After that, the resist may be removed, and a bundle of rod-shaped bodies in which the piezoelectric ceramics are solidified may be baked, or a slurry of piezoelectric ceramics may be directly poured into the holes of the resist pattern having a plurality of holes to form the resist together with the resist. The slurry of piezoelectric ceramics poured into the holes of the pattern is heat-treated to remove the solvent contained in the slurry of piezoelectric ceramics, the resist is burned off, and then the piezoelectric ceramics calcined body from which the solvent has been removed is main-baked. May be.

When a plurality of piezoelectric ceramics thus obtained are dispersed or arranged in a state where the resin is poured and solidified, a composite in which the piezoelectric ceramics are dispersed and embedded in the resin A piezoelectric material is obtained. By providing electrodes on this composite piezoelectric material and subjecting it to polarization treatment, an element can be obtained in which a large number of piezoelectric ceramic rod-shaped bodies each having a small cross section are dispersed in a resin.

[0048]

EXAMPLES Example 1 First, on the substrate 1, polymethylmethacrylate (PMM
A resist layer 2 made of A) is formed to a thickness of 100 to 500 μm (FIG. 1A). Next, using a mask having a pattern of a heavy metal absorbing material such as gold, a resist layer 2 is formed.
After lithographic irradiation with synchrotron radiation is performed, development is performed to obtain a resist pattern 2 '. The obtained resist pattern 2'has a structure in which a plurality of cylindrical bodies having a diameter of about 10 μm are arranged at a predetermined interval on the base material 1 (FIG. 1 (b)).

Next, the substrate 1 having the resist pattern 2'is dipped in a plating solution and a metal structure 3 is deposited by electroplating (FIG. 1 (c)). In this step, nickel, copper or gold etc. can be deposited. Then, the resist is removed to remove the metal structure 3 '.
Is obtained (FIG. 1 (d)). This structure 3'has a diameter of approximately 1
Cylindrical hole 3'a with 0 μm and depth of about 100-500 μm
, Are uniformly dispersed and are formed in large numbers.

Next, the gate plate 4 having a large number of holes is placed on the metal structure 3'obtained as described above, and the slurry 5 of piezoelectric ceramics is poured from above the gate plate 4 (FIG. 1 (e)). )). Next, when the gate plate 4 is separated from the metal structure 3 ', as shown in FIG. 1 (f), rod-shaped bodies 6 of ceramic raw material are collected in a bundle at a predetermined interval. By firing this as it is, a plurality of rod-shaped bodies of piezoelectric ceramics are bundled on the gate plate 4 with a predetermined interval.

Next, as shown in FIG. 1 (g), a resin 7 is poured into and solidified from a bundle of a plurality of piezoelectric ceramic rods 6 '. By the pouring of this resin, the volume fraction of the piezoelectric ceramic is 30 to 5
The shape of the resist pattern is predetermined so as to be 0%.

Then, the gate plate 4 is cut by cutting or the like.
By removing, the composite piezoelectric material 8 in which a large number of piezoelectric ceramic rods are uniformly dispersed in the resin is obtained (FIG. 1).
(H)).

Next, electrodes 9a and 9b are provided on both ends of the composite piezoelectric material 8 and polarization processing is performed to obtain the piezoelectric element 10.

FIG. 2 is a perspective view schematically showing the obtained piezoelectric element. As shown in the figure, the piezoelectric element 10 has a disk shape, and a plurality of rod-shaped bodies 6 ′ made of piezoelectric ceramics are uniformly dispersed in a resin 7. And 9b are formed. In this piezoelectric element, the thickness of the disk-shaped piezoelectric material 8 is about 100 to about 500 μm, and the diameter of each rod-shaped body 6 ′ made of piezoelectric ceramics is about 10 μm. The volume fraction of piezoelectric ceramics in the piezoelectric material 8 is 30 to 50%.

In the above embodiment, the metal structure having a plurality of holes was manufactured by using lithography with synchrotron radiation, but such a structure can also be manufactured by electric discharge machining. For example, as shown in FIG. 3A, a machining electrode 12 is opposed to a metal workpiece 11 having a predetermined size with an extremely small gap, and a pulsed arc discharge is repeated to form a hole 13. You can let it go. After forming holes with a predetermined depth in this manner, the process is repeated to form a plurality of holes 1.
The metal structure 14 in which 3 is formed can be obtained (FIG. 3B). By using the metal structure thus obtained as described above, a piezoelectric element can be formed in the same manner.

Example 2 First, as shown in FIG. 4A, a cylindrical metal body 21 having one end open and the other end closed is prepared. Next, a plurality of holes 22 are formed in the other closed end of the metal body 21 by electric discharge machining (FIG. 4B). The diameter of this hole is about 10
μm.

Next, as shown in FIG. 4C, a gel-like piezoelectric ceramic 23 is filled in the metal body 21 ′ in which the hole 22 is formed, and this is extruded from the hole 22 by the piston 24. . In this way, the rod-shaped body 25 in which the gel-like piezoelectric ceramic is hardened is pushed out from the hole 22. If the extruded rod-shaped body 25 is fired,
As a result, the rod-shaped ceramic piezoelectric bodies 26 are bundled at a predetermined interval (FIG. 4 (d)).

Next, a bundle of a plurality of rod-shaped bodies 26 is immersed in a molten resin 27 to be solidified (FIG. 4).
(E)). The resin 27 is contained in the mold 20 having an appropriate shape. After solidification, the solidified resin is used as the mold 20.
When the end surface is finished by taking it out from the machine and cutting it, a composite material 28 in which a plurality of rod-shaped bodies 26 made of piezoelectric ceramics are uniformly dispersed in a resin 27 is obtained (FIG. 4).
(F)). Electrodes 29a and 29 are provided on both ends of the composite material 28.
The piezoelectric element 3 is formed by forming b and performing polarization processing.
0 is obtained. The piezoelectric element 30 has the same shape as that shown in FIG. 2, the diameter of the rod-shaped body made of piezoelectric ceramics is about 10 μm, and the thickness of the disk-shaped composite piezoelectric material 28 is about 10 μm.
It is 0 to 500 μm. The volume fraction of piezoelectric ceramics in the composite piezoelectric material 28 is 30 to 50%.

In the second embodiment, the metal body used as the nozzle is formed by electric discharge machining, but it may be formed by lithography with synchrotron radiation as shown in the first embodiment.

Embodiment 3 First, in the same manner as in Embodiment 1, a resist pattern 32 having a plurality of holes is formed on a conductive substrate 31 by lithography using synchrotron radiation (FIG. 5).
(A)).

Next, as shown in FIG. 5B, the substrate 31 on which the resist pattern 32 is formed is put into an electrolytic solution 36 in which polarized PZT is pulverized and dispersed. This is used as a cathode, another electrode 33 is provided in the electrolytic solution 36,
Electrodeposition is performed by applying a predetermined voltage between the electrodes. As a result, the piezoelectric ceramics are deposited in the holes 32a of the resist pattern 32.

After that, when the resist pattern 32 is removed by a method such as melting, a bundle of rod-shaped bodies in which the piezoelectric ceramics are hardened is formed on the substrate 31. When this is baked as it is, a rod-shaped body made of piezoelectric ceramics is arranged on the substrate 31 at a predetermined interval.

Next, as shown in FIG. 5C, the rod-shaped body 3
The resin 38 is poured into the array of 7 to be solidified. Next, when the substrate 31 is removed, the composite piezoelectric material 40 in which the rod-shaped bodies made of piezoelectric ceramics are uniformly dispersed in the resin is obtained (FIG. 5D). Next, electrodes 41a and 41b are provided on both ends of the obtained composite piezoelectric material 40 and polarization processing is performed to obtain the piezoelectric element 50 (FIG. 5).
(E)). Such a piezoelectric element has, for example, a shape as shown in FIG.

In the third embodiment, the resist pattern was formed by using lithography with synchrotron radiation. However, a plurality of holes were formed in a metal body having a predetermined size by electric discharge machining, and the holes were used as a mold. By doing so, a plastic structure can be obtained and this can be used as a substitute for the resist pattern.

Embodiment 4 First, in the same manner as in Embodiment 1, a resist pattern 72 having a plurality of holes is formed on a conductive substrate 71 by lithography using synchrotron radiation (FIG. 6).
(A)). Next, a slurry 75 of piezoelectric ceramic is poured according to the resist pattern 72 (FIG. 6B). Next, after evaporating the solvent or the like contained in the piezoelectric ceramic slurry 75 poured into the holes of the resist pattern 72,
Heat treatment is performed at about 400 ° C. to about 500 ° C. to burn off the resist (FIG. 6C). In this step, a ceramic calcined body 77 having a fine structure in which rod-shaped bodies 76 of ceramic raw material are collected in a bundle at a predetermined interval is obtained. Further, by firing the calcined body of this ceramic at a temperature of around 1200 ° C., the ceramic structure 78 having a fine structure in which the rod-shaped bodies 76 ′ of the piezoelectric ceramic are gathered in a bundle at a predetermined interval. Is obtained (FIG. 6 (d)). Next, as shown in FIG. 6E, a resin 79 is poured from above the ceramic structure 78 to be solidified. Next, referring to FIG. 6F, by polishing the protruding portion 78r of the ceramic structure 78 and the protruding portion 79r of the resin 79, a large number of piezoelectric ceramic rod-shaped members are uniformly dispersed in the resin composite. A piezoelectric material 80 is obtained. Next, an electrode 81a and an electrode 81b are provided on both ends of the composite piezoelectric material 80, and polarization processing is performed to obtain a piezoelectric element 90 (FIG. 6 (g)).

Such a piezoelectric element has, for example, a shape as shown in FIG.

In Example 4, the resist pattern was formed by using lithography with synchrotron radiation, but a plurality of holes were formed in a metal body having a predetermined size by electric discharge machining, and the resulting pattern was used as a mold. By doing so, a plastic structure can be obtained and this can be used as a substitute for the resist pattern.

[0068]

As described above, according to the present invention,
It is possible to provide a smaller piezoelectric element having a high piezoelectric constant. The piezoelectric element obtained according to the present invention is
In particular, it is useful as an element used for communication of micromachines, which has recently come into the limelight.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a process for producing a piezoelectric element according to the present invention in Example 1.

FIG. 2 is a perspective view schematically showing the piezoelectric element manufactured in Example 1.

FIG. 3 is a cross-sectional view showing how a metal structure is formed by electrical discharge machining.

FIG. 4 is a cross-sectional view showing how a piezoelectric element is manufactured in Example 2.

5A to 5C are cross-sectional views showing a manner of manufacturing a piezoelectric element in Example 3.

FIG. 6 is a cross-sectional view showing how a piezoelectric element is manufactured in Example 4.

FIG. 7 is a perspective view showing a general form of a composite piezoelectric material.

[Explanation of symbols]

1, 31, 71 Substrate 2 Resist layer 2 ', 32, 72 Resist pattern 3 Metal structure 6', 26, 76 'Piezoelectric rod-shaped body 7, 27, 38, 79 Resin 8, 28, 40, 80 Composite Piezoelectric material 9a, 9b, 29a, 29b, 41a, 41b, 82
a, 82b electrode 10, 30, 50, 90 piezoelectric element

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[Procedure amendment]

[Submission date] May 18, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0003

[Correction method] Change

[Correction content]

This composite piezoelectric material is shown in FIG.
As shown in (a) and (b) respectively, it has a structure in which a cylindrical rod 60a and a prismatic rod 61a made of piezoelectric ceramic are arranged and embedded in the resins 60b and 61b, respectively. . An element using this composite material can have higher sensitivity to ultrasonic waves than piezoelectric ceramics. Such materials are used for receiving elements such as sonar.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0067

[Correction method] Change

[Correction content]

In Example 4, the resist pattern having a plurality of holes was formed by lithography with synchrotron radiation, and the pattern shown in FIGS. 1 (a) to 1 (d) was used.
Having multiple needle-like structures on the surface, created by the process
Using the metal structure 3 ′ as a mold, a plurality of molds
It is also possible to obtain a plastic structure having the above holes and use this as a substitute for the resist pattern. In addition,
For metal objects with noise, the surface is processed by electrical discharge machining.
Forming multiple needle-like structures and using them as a mold
The plastic structure is obtained by and the resist pattern is
It can also be used as a substitute for the cord.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical indication H01L 41/26

Claims (4)

[Claims] 1. A piezoelectric element in which an electrode is provided on a piezoelectric material having a vibration mode in a radial direction, wherein the piezoelectric material contains a plurality of rod-shaped bodies made of piezoelectric ceramic in a polymer in an amount of 30% to 50%. Piezoelectric elements that are dispersed and embedded at a volume fraction. 2. A step of forming a resist pattern on the resist layer by using lithography with synchrotron radiation after forming the resist layer, and forming a structure having a plurality of holes using the resist pattern as a prototype. Introducing a raw material of piezoelectric ceramics into the holes of the structure,
A step of forming a plurality of piezoelectric ceramic rods according to the shape of the hole; a step of solidifying the plurality of rods with resin; and an electrode provided on the rods solidified with resin to perform polarization processing. A method for manufacturing a piezoelectric element, comprising: 3. A step of forming a mold having a plurality of holes by electric discharge machining, and a step of introducing a raw material of piezoelectric ceramics into the holes of the mold to form a plurality of piezoelectric ceramic rods conforming to the shape of the holes. And a step of solidifying the plurality of rod-shaped bodies with a resin, and a step of providing electrodes on the rod-shaped bodies solidified with a resin and performing a polarization treatment. 4. A step of forming a resist pattern having a plurality of holes in the resist layer by using lithography with synchrotron radiation after forming the resist layer, and introducing a piezoelectric ceramic material into the holes of the resist pattern. Then, a step of forming a plurality of rod-shaped bodies of piezoelectric ceramics according to the shape of the holes, a step of solidifying the plurality of rod-shaped bodies with a resin, and an electrode provided on the rod-shaped body solidified with a resin. A method of manufacturing a piezoelectric element, comprising the step of performing a polarization treatment.