JPH10264384A - Ink-jet type recording head, its manufacture, and piezoelectric element thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrict deterioration of a piezoelectric characteristic due to a reduction action to platinum by titanate zirconate, etc., when the titanate zirconate, etc., is used for a piezoelectric layer, by layering to the piezoelectric layer an electrode film formed of a composition which obstructs the reduction action by hydrolysis of the piezoelectric layer, thereby forming a piezoelectric element. SOLUTION: An insulating film 31 and a lower electrode film 32 are layered as a diaphragm 3 on a substrate. A piezoelectric layer 41, a first and a second upper electrode films 42, 43 are layered as a piezoelectric element 4. In the thus-constituted recording head, the piezoelectric layer 41 is formed of a material changing a volume greatly when a voltage is impressed particularly titanate zirconate. The first upper electrode film 42 is set to act as a separation layer preventing a reduction action to the piezoelectric layer 41. A material of the first upper electrode film 42 is such that does not act as a catalyst to moisture and not generate hydrogen even if the moisture in the atmosphere is taken into the piezoelectric layer 41, for instance, titanium(Ti) is used when platinum(Pt) is used for the second upper electrode film 43.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an on-demand type ink jet recording head for printing on a recording medium by ejecting ink droplets from a nozzle, and more particularly, to a titanium zirconate which is applied to a piezoelectric material whose volume is changed by voltage application. Lead acid (P
The present invention relates to an invention for preventing a reduction action of an electrode caused when ZT) or the like is used.

[0002]

2. Description of the Related Art An on-demand type ink jet recording head is a type in which a voltage is applied to a piezoelectric element formed on a vibration plate to cause a volume change, thereby instantaneously increasing the pressure in a pressure chamber. This is to eject indoor ink droplets onto a recording medium.

A conventional piezoelectric element for an ink jet recording head has a piezoelectric layer in which lead zirconate titanate (P) is used.
ZT), and platinum (Pt)
Was used. Lead zirconate titanate is known as a piezoelectric material exhibiting suitable piezoelectric characteristics. Platinum itself is not easily oxidized and has excellent chemical and physical stability, so that it was excellent as an electrode material to be formed on a fine piezoelectric material.

However, since the upper electrode of the electrode film sandwiching the piezoelectric layer has a structure that is exposed to the atmosphere, when water vapor in the atmosphere enters the piezoelectric layer of lead zirconate titanate, In some cases, water is reduced by platinum to generate hydrogen, which may deteriorate the piezoelectric characteristics of the piezoelectric layer.
Due to the generation of hydrogen, the dielectric constant of the piezoelectric layer decreases, and the volume change rate due to the application of a voltage deteriorates.

[0005]

SUMMARY OF THE INVENTION In view of the above problems, the present invention provides a structure of a piezoelectric element in which piezoelectric characteristics are less likely to be degraded due to the reduction action of platinum. The purpose is to increase reliability.

That is, a first object of the present invention is to provide a piezoelectric element which does not cause reduction of water by platinum such as lead zirconate titanate when the piezoelectric layer is made of lead zirconate titanate or the like. The composition of the electrode is provided.

A second object of the present invention is to provide an electrode structure which does not cause a water reducing action on lead zirconate titanate or the like of a piezoelectric layer even when platinum is used as an electrode material. is there.

A third object of the present invention is to provide a method of manufacturing an ink jet recording head having a piezoelectric element which can solve the second object.

[0009]

According to a first aspect of the present invention, there is provided an ink jet recording head having a diaphragm provided with at least one piezoelectric element on at least one surface of a pressure chamber substrate filled with ink. In the piezoelectric element, the piezoelectric layer that changes in volume by applying a voltage,
The piezoelectric layer is formed by laminating electrode films each having a composition that prevents a reduction effect of the piezoelectric layer by hydrolysis.

According to the second aspect of the present invention, the electrode film has a first upper electrode film containing titanium (Ti) laminated on the piezoelectric layer side, and contains platinum (Pt) on the first upper electrode film. Second
2. The ink jet recording head according to claim 1, wherein an upper electrode film is laminated, and a thickness of the first upper electrode film is 3 nm or more and 30 nm or less.

According to the third aspect of the present invention, the piezoelectric layer includes:
Lead (Pb), zirconium (Zr) and titanium (T
i), and the electrode film is made of gold (A)
u), iridium (Ir), nickel (Ni), tungsten (W), aluminum (Al), ruthenium (R
u), iridium oxide (IrOx) or ruthenium oxide (RuOx).
Is an ink jet recording head.

[0012] In the invention described in claim 4, the electrode film includes the first upper electrode film laminated on the piezoelectric layer side and the second upper electrode film laminated on the first upper electrode film. When the composition of the second upper electrode film is gold (Au), chromium (Cr) is laminated as the first upper electrode film, and when the composition of the second upper electrode film is iridium (Ir). The ink jet recording head according to claim 3, wherein iridium oxide (IrOx) is laminated as the first upper electrode film.

According to a fifth aspect of the present invention, a piezoelectric layer composed of an oxide containing lead (Pb), zirconium (Zr) and titanium (Ti) is made of gold (Au), iridium (I
r), a layer sandwiched by an electrode film containing any one of nickel (Ni), tungsten (W), aluminum (Al), ruthenium (Ru), iridium oxide (IrOx), and ruthenium oxide (RuOx) A piezoelectric element having a structure.

In the invention according to claim 6, the electrode film includes the first upper electrode film laminated on the piezoelectric layer side and the second upper electrode film laminated on the first upper electrode film. When the composition of the second upper electrode film is gold (Au), chromium (Cr) is laminated as the first upper electrode film, and when the composition of the second upper electrode film is iridium (Ir). The piezoelectric element according to claim 5, wherein iridium oxide (IrOx) is laminated as the first upper electrode film.

According to a seventh aspect of the present invention, there is provided a method of manufacturing an ink jet recording head, wherein a diaphragm having one or more piezoelectric elements is provided on at least one surface of a pressure chamber substrate filled with ink. Forming a piezoelectric layer composed of an oxide containing lead (Pb), zirconium (Zr) and titanium (Ti) on the diaphragm via a lower electrode film; A method for manufacturing an ink jet recording head, comprising: a step of forming an upper electrode film; and a step of forming a second upper electrode film on the first upper electrode film.

According to an eighth aspect of the present invention, when the composition of the second upper electrode film is platinum (Pt), titanium (Ti) is laminated as the first upper electrode film, and the composition of the second upper electrode film is When gold (Au) is used, chromium (Cr) is laminated as the first upper electrode film, and when the composition of the second upper electrode film is iridium (Ir), iridium oxide (Ir) is used as the first upper electrode film. The method of manufacturing an ink jet recording head according to claim 7, wherein IrOx) is laminated.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a preferred embodiment of the present invention will be described with reference to the drawings.

<Embodiment 1> Embodiment 1 of the present invention prevents the characteristic deterioration of the piezoelectric element by laminating an upper electrode film.

(Description of Configuration) As shown in FIG. 1, an ink jet printer 100 according to the present embodiment includes an ink jet printer head 101, a main body 102, a tray 103 and the like of the present invention.

As shown in FIG. 1, when the paper 105 is fed, the ink jet printer head 101 is driven in the direction of the arrow in FIG.
It is configured to be able to print on the paper 105 with ink droplets ejected from the printer.

The main body 102 has a tray 103 in which the ink jet printer head 101 is drivably arranged. Further, when print information is transmitted from a computer (not shown), the ink jet printer head 1 is placed on the paper 105 supplied from the tray 103.
01, and the paper after printing can be discharged to the discharge port 104.

The tray 103 is a table on which the paper 105 is placed, and is configured to be able to supply the paper 105 into the main body 102 at the time of paper feeding.

As shown in FIGS. 2 and 3, the ink jet printer head 101 includes a nozzle plate 1, a pressure chamber substrate 2, a vibration plate 3, and a housing 5.

When the nozzle plate 1 is bonded to the pressure chamber substrate 2, the nozzle 11 is arranged at a position corresponding to each of a plurality of cavities (pressure chambers) 21 provided in the pressure chamber substrate 2. ing.

The pressure chamber substrate 2 includes a cavity 21 and a side wall 2.
2, a reservoir 23 and a supply port 24 are provided. The cavities 21 are formed by etching a substrate made of silicon or the like, the side walls 22 are configured to partition between the cavities 21, and the reservoirs 23 serve as a common flow path that can supply ink to each cavity 21 when ink is filled. It is configured. The supply port 24 is configured so that ink can be introduced into each cavity 21.

The housing 5 is formed of resin or metal, and is configured to be capable of housing the pressure chamber substrate 2 to which the nozzle plate 1 and the vibration plate 3 are attached. The housing 5 is configured to be supplied with ink from an ink tank (not shown) and to supply the ink into the pressure chamber substrate 2 via the ink tank port 33 shown in FIG.

As shown in FIG. 3, the diaphragm film 3 has a structure that can be bonded to one surface of the pressure chamber substrate 2 or is formed on the pressure chamber substrate by a thin film process. The piezoelectric element 4 is formed on the diaphragm 3 in a predetermined shape.

The layer structure of the vibrating plate film 3 and the piezoelectric element 4 (section AA in FIG. 3) is, as shown in FIG. An insulating film 31 and a lower electrode film 32 are laminated as a plate 3 and a piezoelectric element 4
The piezoelectric layer 41, the first upper electrode film 42, and the second
The upper electrode film 43 is formed by lamination.

The substrate 20 is composed of silicon or the like which is easy to process. The opposite side of the substrate corresponding to the position where the piezoelectric element 4 is formed is etched to form a cavity 21. The substrate 20 has an appropriate mechanical strength,
In order to provide an appropriate height as a pressure chamber substrate, for example, 2
It has a thickness of about 00 μm.

The insulating film 31 is made of a material having no conductivity, for example, silicon dioxide formed by thermally oxidizing a silicon substrate. The insulating film 31 is deformed by the volume change of the piezoelectric layer, and the pressure inside the cavity 21 is reduced. It is configured to be able to increase instantaneously. The insulating film 31 is formed with a thickness of, for example, about 1 μm so that appropriate strength and insulating properties can be maintained.

The lower electrode film 32 is the other electrode paired with the upper electrode film 40 for applying a voltage to the piezoelectric layer, and is made of a conductive material, for example, platinum (Pt).
It is formed by molding with a thickness of about 0 nm. Further, a stacked structure may be provided to improve the adhesion between platinum and the piezoelectric layer 41 or the insulating film 31. For example, on the insulating film 31, a titanium (Ti) layer, a titanium oxide layer, a titanium (Ti)
Layer, a platinum (Pt) layer, and a titanium (Ti) layer may be sequentially stacked.

The piezoelectric layer 41 is made of a material that undergoes a large volume change when a voltage is applied. Such materials include lead (Pb), zirconium (Zr), titanium (Ti), magnesium (Mg) and niobium (Nb).
And ceramics such as nickel (Ni) or tungsten (W). In particular, lead zirconate titanate (Pb (ZrTi) O ₃ ; PZ
T) and the like are typical. The piezoelectric layer 41 is preferably formed by applying and laminating the same material a plurality of times. If the thickness of the entire piezoelectric layer is too large, the thickness of the entire layer becomes too large, and a high drive voltage is required, and cracks are easily formed due to distortion due to internal stress, which causes defects. If the thickness is too small, the film thickness cannot be made uniform, the characteristics of each piezoelectric element separated after etching vary, or the number of manufacturing steps increases, and manufacturing cannot be performed at a reasonable cost. Further, if the thickness is too small, it cannot withstand the driving voltage, causing a problem of causing dielectric breakdown. Therefore, the number of layers in each piezoelectric layer is preferably from 4 to 36 layers, and particularly preferably about 8 layers.
1 The total film thickness is preferably set to about 600 nm to 3600 nm, particularly preferably about 800 nm to 2000 nm.

The first upper electrode film 42 is configured to function as an isolation layer for preventing the piezoelectric layer 41 from reducing. The first upper electrode film 42 is determined by what kind of material is used for the second upper electrode film 43. The material of the first upper electrode film is required to have the following properties.

A) The composition is such that, even if moisture in the air is taken into the piezoelectric layer 41, the composition acts so as not to generate hydrogen by acting on the moisture as a catalyst. B) The piezoelectric layer 41 and the second upper electrode film 43 When platinum (Pt) is used for the second upper electrode film as a material satisfying such requirements, it is preferable to use titanium (Ti) for the first upper electrode film. Titanium is water (H
_{This is because 2} O) is not reduced and has high adhesion to platinum. The thickness of the first upper electrode film 42 is preferably 3 nm or more and 30 nm or less. If the film thickness is too large, titanium takes in oxygen in the piezoelectric layer, and titanium oxide (TiOx) having a low dielectric constant is formed. For this reason, even if a voltage is applied, the substantial voltage applied to the piezoelectric layer is reduced, so that there is a disadvantage that a sufficient volume change cannot be generated. On the other hand, if the thickness is too small, titanium serving as an adhesion agent is formed in an island shape and does not completely cover the piezoelectric layer, so that the adhesion between platinum as the second upper electrode material and the piezoelectric layer is made. Power drops. Further, since a region where platinum directly contacts the piezoelectric layer appears, there is a disadvantage that hydrogen generated by reduction of water by platinum invades the piezoelectric layer, thereby deteriorating piezoelectric characteristics.

The second upper electrode film 43 is configured to function as an original electrode thin film. That is, it is desired that the material of the second upper electrode film 43 be a good conductive material and a chemically and physically stable material. As a material having such properties, gold (Au) or platinum (Pt) is preferable. The thickness of the second upper electrode film 43 is set to a thickness that can maintain uniformity as an electrode film, for example, about 0.1 μm.

When a reduction action of water taken in the piezoelectric layer occurs between the lower electrode film and the piezoelectric layer, the first upper electrode is disposed between the lower electrode and the piezoelectric layer. A corresponding intermediate layer may be provided. For example, when platinum is used as the lower electrode film, a titanium layer is provided as the intermediate layer.

(Operation) Conventionally, platinum as the upper electrode is
It was in direct contact with the piezoelectric layer. Since water vapor exists in the atmosphere, the water vapor is taken into the piezoelectric layer from the side wall of the piezoelectric layer exposed to the space. Platinum is water (H ₂
O) acts as a catalyst to reduce water and produce hydrogen (H ₂ )
Generate. When hydrogen was generated, the dielectric constant of the piezoelectric material decreased, and the piezoelectric characteristics were degraded.

In the present invention, since the first upper electrode film 42 made of a material that does not exert a water reducing action is interposed between the piezoelectric layer 41 and the second upper electrode film 43, the piezoelectric layer has moisture. Does not degrade the characteristics of the piezoelectric body.

Next, the principle of ink droplet ejection will be described. In the ink jet printer head of the present invention, in the piezoelectric element 4 having the layer structure of FIG.
And a lower electrode 32 are connected so that a drive voltage can be applied. Unless a voltage is applied between the second upper electrode film and the lower electrode film, the volume of the piezoelectric layer does not change. Therefore, in the cavity 21 (see FIG. 3) provided with the piezoelectric element 4 to which no voltage is applied, no volume change occurs, and no ink droplet is ejected.

On the other hand, when a constant voltage (for example, 15 V) is applied between the second upper electrode film and the lower electrode film, a change in volume occurs in the piezoelectric layer. For this reason, in the cavity 21 in which the piezoelectric element 4 to which a certain voltage is applied is provided, the diaphragm 3 is deformed by the volume change of the piezoelectric element 4, and the volume in the cavity 21 is reduced. For this reason, the cavity 21
The internal pressure of the ink inside increases instantaneously, and ink droplets are ejected from the nozzle 11.

(Description of Manufacturing Method) Next, a method of manufacturing the ink jet printer head of the present invention will be described.

Step of forming piezoelectric layer (FIG. 5A):
An insulating film 31 serving as the diaphragm film 3 and a lower electrode film 32 are formed on the silicon substrate 20. The insulating film 31 is, for example, 110
It is formed by flowing dry oxygen in a furnace at 0 ° C. and thermally oxidizing it for about 22 hours to form a thermal oxide film having a thickness of about 1 μm. Alternatively, a thermal oxide film having a thickness of about 1 μm may be formed by flowing oxygen containing water vapor in a furnace at 1100 ° C. and performing thermal oxidation for about 5 hours. The insulating film formed by these methods not only provides electrical insulation but also serves as a protective layer against etching.

As the lower electrode film 32, for example, the titanium layer is about 200 nm, the titanium oxide layer is about 200 nm, the titanium layer is about 5 nm, the platinum is about 500 nm, and the titanium layer is about 5 nm. The layers are formed by sequentially laminating the layers. Note that a platinum layer having a thickness of about 800 nm may be formed by a sputtering method or the like. However, a titanium layer below the platinum layer is required.

Next, a piezoelectric layer 41 is formed. Piezoelectric ceramic materials (for example, lead zirconate titanate: P
ZT) or a material mainly composed of a solid solution thereof,
The lower electrode film 32 is applied (formed) by spin coding. When eight layers are stacked as in this embodiment, the thickness of each layer is about 125 nm. In order to equalize the thickness of each layer, the rotation speed of the turntable for spin coating is set to a low rotation speed (for example, 500 rpm.
Starting at about 30 seconds), gradually increasing the rotation speed (for example, about 1500 seconds at 1500 rpm), and finally reducing the speed again (for example, about 10 seconds at 500 rpm).
Adjust the speed so that

Dry degreasing step (FIG. 9B): The piezoelectric layer 41b immediately after the application is a precursor of an amorphous piezoelectric film and is not crystallized. Therefore, after applying the material, the material is dried at a constant temperature (for example, 180 degrees) for a certain time (for example, about 10 minutes). After drying, the organic solvent is further degreased at a predetermined high temperature (for example, 400 ° C.) for a certain time (30 minutes) to evaporate the organic solvent.

When a plurality of layers are laminated, the application, drying and degreasing of the piezoelectric ceramic material are repeated to obtain a desired thickness.

After the piezoelectric body is laminated to a desired thickness, heat treatment is performed in a predetermined atmosphere to further promote the crystallization of the ceramic layer and improve the characteristics of the piezoelectric body. For example, rapid heat treatment (RTA: Rapid Th
Heat at 600 ° C. for 5 minutes and 725 ° C. for 1 minute for thermal annealing.

First Upper Electrode Forming Step (FIG. 4C): A first upper electrode film 42 is formed on the piezoelectric layer 41 by using a technique such as an electron beam evaporation method or a sputtering method. The material of the first upper electrode is titanium when platinum is used for the second upper electrode film 43. The film thickness is 3 nm or more and 3
Adjust so as to be 0 nm or less.

Second upper electrode forming step (FIG. 3D): A second upper electrode film 43 is formed on the first upper electrode film 42.
Is formed using techniques such as an electron beam evaporation method and a sputtering method. The material of the second upper electrode is platinum when titanium is used for the first upper electrode film 42. The film thickness is 100
The thickness is about nm.

Etching step (FIG. 7E): After each layer is formed, the laminated structure on the diaphragm film 3 is masked so as to have a shape conforming to the shape of each cavity, and the periphery thereof is etched to form a second layer. The upper electrode film, the first upper electrode, and the piezoelectric layer are removed. That is, a resist having a uniform thickness is applied by using a method such as a spinner method or a spray method, and is exposed and developed to form a resist on the second upper electrode film 43.
Unnecessary layer structure portions are removed by applying ion milling, dry etching, or the like that is usually used.

Further, a cavity 21 is formed on the other surface of the pressure chamber substrate 2. For example, the cavity space is etched using anisotropic etching using an active gas such as anisotropic etching and parallel plate type reactive ion etching. The portion left without being etched becomes the side wall 22. The nozzle plate 1 is attached to the pressure chamber substrate 2 after the etching using an epoxy resin or the like. At this time, the nozzles 11 are aligned so as to be arranged in the respective spaces of the cavity 21 of the pressure chamber substrate 2. When the pressure chamber substrate 2 to which the nozzle plate 1 is attached is attached to the housing 5, the ink jet printer head 101 is completed.

As described above, according to the first embodiment, since the first upper electrode film as an intermediate layer is interposed between the second upper electrode film and the piezoelectric layer, moisture is taken in the piezoelectric layer. Even if it is, the reduction effect does not work. Therefore, the piezoelectric characteristics of the piezoelectric element are not deteriorated.

<Embodiment 2> In Embodiment 2 of the present invention, the composition of the upper electrode film is different from that of conventional platinum,
This is to prevent the characteristic deterioration of the piezoelectric element.

As shown in FIG. 6, the piezoelectric element 4b according to the second embodiment does not include the first upper electrode
The second upper electrode film 43 is provided directly on the first upper electrode film 43.

The insulating film 31 forming the substrate 20 and the diaphragm 3
The compositions of the lower electrode 32 and the piezoelectric layer 41 are the same as in the first embodiment. However, the composition of the second upper electrode 43 is gold (Au), iridium (Ir), nickel (N
i), tungsten (W), aluminum (Al), ruthenium (Ru), iridium oxide (IrOx), or ruthenium oxide (RuOx).

When gold is used as the second upper electrode film, an intermediate layer 44 (shown by a broken line in FIG. 6) made of chromium (Cr) is provided at a position corresponding to the first upper electrode film of the first embodiment. Forming is preferred. When iridium (Ir) is used as the second upper electrode film, it is preferable to interpose an intermediate layer 44 made of iridium oxide (IrOx). These intermediate layers 44 function to enhance the adhesion between the piezoelectric layer 41 and gold or iridium as the second upper electrode film 43.

As described above, according to the second embodiment, since the composition of the second upper electrode film does not exert a reducing effect on the moisture taken in the piezoelectric layer, deterioration of the characteristics of the piezoelectric element can be prevented. .

<Other Modifications> The present invention can be variously modified irrespective of the above embodiment. For example,
Although the present invention is mainly applied to a piezoelectric element of an ink jet printer head, the piezoelectric layer formed by the present invention may be used as a piezoelectric element sandwiched between two electrode films. That is, if the laminated structure in which the piezoelectric layer 41, the first upper electrode film 42, and the second upper electrode film 43 are laminated from the lower electrode film 32 of the present invention is cut out so as to have a shape corresponding to the size of the application target. Thus, a high-performance piezoelectric element can be obtained. According to the piezoelectric layer of the present invention, since there is no deterioration in piezoelectric characteristics, a highly reliable piezoelectric element can be provided. Examples of applications of such a piezoelectric element include a piezoelectric accelerometer, a piezoelectric crystallite, a piezoelectric speaker, a piezoelectric pickup, and a piezoelectric microphone.

[0059]

According to the present invention, it is possible to provide a structure of a piezoelectric element in which deterioration of piezoelectric characteristics due to reduction action of platinum is small. Thereby, the reliability of the ink jet recording head and the piezoelectric element can be improved.

That is, according to the present invention, there is provided a piezoelectric element in which, for example, when lead zirconate titanate or the like is used in the piezoelectric layer, the action of reducing the moisture by platinum such as lead zirconate titanate does not occur. it can.

Further, according to the present invention, even when platinum is used as the electrode material, it is possible to provide an electrode structure which does not cause a water reducing action on lead zirconate titanate or the like of the piezoelectric layer.

Further, according to the present invention, it is possible to provide a method of manufacturing an ink jet recording head provided with a piezoelectric element having the above-described effects.

[Brief description of the drawings]

FIG. 1 is an overall perspective view of an ink jet printer of the present invention.

FIG. 2 is an exploded perspective view of the inkjet printer head of the present invention.

FIG. 3 is a perspective view and a partial cross-sectional view of a pressure chamber substrate of the ink jet printer head of the present invention.

FIG. 4 is a cross-sectional view illustrating a layer structure (first embodiment) of the piezoelectric element of the present invention, in which one piezoelectric element is observed from a cross section taken along line AA in FIG.

FIG. 5 is a manufacturing process sectional view for explaining the method for manufacturing the ink jet printer head of the present invention.

FIG. 6 is a cross-sectional view illustrating a layer structure (second embodiment) of another piezoelectric element of the present invention, in which one piezoelectric element is observed from an AA cross section in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Nozzle plate 2 ... Pressure chamber substrate 3 ... Vibration plate 4 ... Piezoelectric element 21 ... Cavity 31 ... Insulating film 32 ... Lower electrode film 41 ... Piezoelectric layer 42 ... First upper electrode film 43 ... Second upper electrode film 44 … Intermediate layer

Claims (8)

[Claims] 1. An ink jet recording head having a diaphragm provided with at least one piezoelectric element on at least one surface of a pressure chamber substrate filled with ink, wherein the piezoelectric element applies a voltage. An ink jet recording head comprising: a piezoelectric layer that changes in volume by performing the above operation; and an electrode film having a composition that prevents a reduction action of water mixed in the piezoelectric layer. 2. The electrode film, wherein a first upper electrode film containing titanium (Ti) is laminated on the piezoelectric layer side, and a second upper electrode film containing platinum (Pt) on the first upper electrode film. Are laminated, and the thickness of the first upper electrode film is 3 nm or more and 30 nm or more.
The ink jet recording head according to claim 1, wherein: 3. The piezoelectric layer is made of an oxide containing lead (Pb), zirconium (Zr) and titanium (Ti), and the electrode film is made of gold (Au), iridium (I).
2. The ink jet recording head according to claim 1, wherein the ink jet recording head is made of any one of r), nickel (Ni), tungsten (W), aluminum (Al), ruthenium (Ru), iridium oxide (IrOx), and ruthenium oxide (RuOx). . 4. An electrode film comprising: a first upper electrode film laminated on a piezoelectric layer side; and a second upper electrode film laminated on the first upper electrode film. When the composition of the electrode film is gold (Au), chromium (Cr) is laminated as the first upper electrode film, and when the composition of the second upper electrode film is iridium (Ir), the first upper electrode film is the first. 4. The ink jet recording head according to claim 3, wherein iridium oxide (IrOx) is laminated as the upper electrode film. 5. A piezoelectric layer comprising an oxide containing lead (Pb), zirconium (Zr) and titanium (Ti) is composed of gold (Au), iridium (Ir), nickel (N
i) having a layer structure sandwiched by an electrode film composed of any one of tungsten (W), aluminum (Al), ruthenium (Ru), iridium oxide (IrOx), and ruthenium oxide (RuOx) A piezoelectric element characterized by the above-mentioned. 6. An electrode film comprising: a first upper electrode film laminated on a piezoelectric layer side; and a second upper electrode film laminated on the first upper electrode film. When the composition of the electrode film is gold (Au), chromium (Cr) is laminated as the first upper electrode film, and when the composition of the second upper electrode film is iridium (Ir), the first upper electrode film is the first. The piezoelectric device according to claim 5, wherein iridium oxide (IrOx) is laminated as the upper electrode film. 7. A method for manufacturing an ink jet recording head, wherein a vibration plate having one or more piezoelectric elements is provided on at least one surface of a pressure chamber substrate filled with ink, wherein: Forming a piezoelectric layer having an oxide containing lead (Pb), zirconium (Zr) and titanium (Ti) via a lower electrode film; and forming a first upper electrode film on the piezoelectric layer. Forming a second upper electrode film on the first upper electrode film. A method for manufacturing an ink jet recording head, comprising: 8. The composition of the second upper electrode film is platinum (P).
t), titanium (Ti) is laminated as the first upper electrode film, and the composition of the second upper electrode film is gold (A).
u), chromium (Cr) is laminated as the first upper electrode film, and when the composition of the second upper electrode film is iridium (Ir), iridium oxide (Ir) is used as the first upper electrode film. The method for manufacturing an ink jet recording head according to claim 7, wherein IrOx) is laminated.