JP3567977B2 - Piezoelectric element, ink jet recording head, printer, and method of manufacturing piezoelectric element - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a piezoelectric element having an electromechanical conversion function, and particularly to a piezoelectric element, an ink jet recording head, a printer, and a piezoelectric element that can obtain excellent piezoelectric characteristics when used in an ink jet recording head. It relates to a manufacturing method.
[0002]
[Prior art]
The ink jet recording head uses a piezoelectric element as a driving source for ink ejection of a printer. This piezoelectric element generally includes a piezoelectric thin film and an upper electrode and a lower electrode which are arranged to sandwich the piezoelectric thin film.
[0003]
2. Description of the Related Art Conventionally, piezoelectric elements having improved characteristics by defining the crystal structure of a thin film made of lead zirconate titanate (PZT) or forming a Ti nucleus on a lower electrode have been developed. For example, JP-A-10-81016 discloses a PZT thin film having a rhombohedral crystal structure and a predetermined degree of orientation. Japanese Patent Application Laid-Open No. 8-335676 discloses a piezoelectric element in which a titanium nucleus is formed on an Ir lower electrode.
[0004]
However, the conventional piezoelectric element has a problem that it is difficult to stably obtain a predetermined degree of orientation of the piezoelectric thin film with good reproducibility. With such a piezoelectric element, it is difficult to obtain stable and high piezoelectric characteristics, and this is a factor that makes it difficult to obtain sufficient printing performance of an ink jet recording head or a printer.
[0005]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION It is an object of the present invention to provide a piezoelectric element having stable and high piezoelectric characteristics by solving the above problems and obtaining a predetermined orientation degree of a piezoelectric thin film with good reproducibility and an ink jet using the same. An object of the present invention is to provide a method of manufacturing a recording head, a printer, and a piezoelectric element.
[0006]
[Means for Solving the Problems]
A piezoelectric element according to an embodiment of the present invention includes a piezoelectric element including: a lower electrode formed on a ZrO ₂ film; a piezoelectric film formed on the lower electrode; and an upper electrode formed on the piezoelectric film. An element, wherein the piezoelectric film has a degree of 100-plane orientation measured by an X-ray diffraction wide angle method of 40% or more and 70% or less.
[0007]
It is preferable that the degree of orientation in the 110 plane is 10% or less, and the degree of orientation in the 111 plane is the remainder.
[0008]
In particular, the lower electrode is
(1) At least a first layer containing Ir and located on the uppermost layer, and a second layer containing Pt and located on the next layer, and the thickness of the second layer is smaller than the thickness of the entire lower electrode. A Ti layer having a thickness of 4 nm to 6 nm is formed on the lower electrode, and a piezoelectric film is formed on the Ti layer. Also,
(1) -1 It may include a third layer that is the next layer of the second layer and is located at the lowermost layer of the lower electrode and contains Ir.
{Circle around (1)} Among the lower electrodes, the second layer containing Pt may be a lowermost layer.
[0009]
Further, the lower electrode includes:
(2) At least a first layer containing Pt located on the uppermost layer and a second layer containing Ir located on the next layer, and the thickness of the first layer is smaller than the thickness of the entire lower electrode. 20% or more and 40% or less, a Ti core layer having a thickness of 4 nm or more and 6 nm or less is formed on the lower electrode, and a piezoelectric film is formed on the Ti layer. Also,
{Circle around (2)}-1 Among the lower electrodes, the second layer containing Ir may be the lowermost layer.
[0010]
Further, the present invention is an ink jet recording head, wherein the above-described piezoelectric element is provided as a piezoelectric actuator on a diaphragm which is an installation surface.
[0011]
Further, the present invention is a printer comprising the ink jet recording head as a printing unit.
[0012]
Further, the present invention provides a step of forming a ZrO ₂ film on a substrate, a step of forming a lower electrode on the ZrO ₂ film, and a step of forming a Ti nucleus layer having a thickness of 4 nm or more and 6 nm or less on the lower electrode. Forming, a step of forming a piezoelectric precursor film on the Ti layer, and a firing step, a method for manufacturing a piezoelectric element,
{Circle around (1)} The lower electrode includes at least a first layer located on the uppermost layer and containing Ir, and a second layer located on the next layer and containing Pt, and the thickness of the second layer is the entire lower electrode. Forming the lower electrode, comprising: forming the second layer including Pt; and forming the first layer including Ir on the second layer. And at least a step of forming, or,
{Circle around (2)} The lower electrode includes at least a first layer containing Pt located on the uppermost layer, and a second layer containing Ir located on the next layer, and the thickness of the first layer is the entire lower electrode. 20% or more and 40% or less with respect to the thickness of the first layer. The step of forming the lower electrode includes the step of forming the second layer containing Ir and the step of forming the first layer containing Pt on the second layer. At least a step of forming
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
(Explanation of principle)
FIG. 9 shows a lower electrode laminated on a ZrO ₂ film in the order of Ir layer / Pt layer / Ir layer, a Ti nucleus, and a piezoelectric precursor film formed and crystallized. The figure which measured the relationship between the degree of 100 plane orientation of a piezoelectric thin film and the thickness of Ti nucleus about an element is shown. In FIG. 9, the symbol (A) indicates a case where the thickness of the lower electrode second layer including Pt is about 10% of the entire thickness of the lower electrode. In this case, when the thickness of the Ti nucleus is 4 nm or more and 6 nm or less, the degree of 100-plane orientation can be increased to about 90%. However, when trying to adjust the degree of 100-plane orientation to a value different from this, the fluctuation of the degree of 100-plane orientation with respect to the change in the thickness of the Ti nucleus is too large, and a desired degree of 100-plane orientation can be stably obtained with good reproducibility. I can't.
[0014]
On the other hand, the symbol (a) in FIG. 9 indicates a case where the ratio of the thickness of the second layer of the lower electrode including Pt to the thickness of the entire lower electrode is increased from the case (a). In this case, under the influence of Pt, the degree of orientation of the 111 plane of the piezoelectric thin film increases, the degree of orientation of the 100 plane becomes lower than in the case of (A), and the thickness of the Ti nucleus is 4 nm or more and 6 nm or less. , 100 plane orientation degree shows a stable value.
[0015]
As described above, by controlling the thickness of the Ti nucleus to 4 to 6 nm and adjusting the ratio of the thickness of the Pt layer to the total thickness of the lower electrode, the degree of 100 plane orientation (100 plane orientation and 111 plane orientation) is obtained. Ratio with the degree) can be adjusted to a desired ratio with good reproducibility.
[0016]
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
[0017]
(Embodiment 1)
FIG. 1 is a sectional view of the layer structure in which the piezoelectric element portion of the ink jet recording head according to the present embodiment is enlarged.
[0018]
As shown in FIG. 1, the piezoelectric element 40 is configured by sequentially laminating a ZrO ₂ film 32, a lower electrode 42, a piezoelectric thin film 43, and an upper electrode 44 on an oxide film 31.
[0019]
Oxide film 31 is formed on pressure chamber substrate 20 made of, for example, single-crystal silicon having a thickness of 220 μm. Preferably, a film made of silicon oxide (SiO ₂ ) is formed to a thickness of 1.0 μm.
[0020]
The ZrO ₂ film 32 is a layer having elasticity, and constitutes the diaphragm 30 integrally with the oxide film 31. Since the ZrO ₂ film 32 has a function of giving elasticity, it preferably has a thickness of 200 nm or more and 800 nm or less.
[0021]
Between the ZrO ₂ film 32 and the lower electrode 42, an adhesion layer (not shown) made of metal, preferably titanium or chromium, for adhering both layers may be provided. The adhesion layer is formed to improve the adhesion to the installation surface of the piezoelectric element, and may not be formed if the adhesion can be ensured. In the case where an adhesion layer is provided, the thickness is preferably 10 nm or more to ensure the minimum adhesion.
[0022]
The lower electrode 42 includes a third layer 423 located at the lowermost layer and containing Ir, a second layer 424 having a thickness of 30% or more and 50% or less of the thickness of the lower electrode 42 and containing Pt, And a first layer 425 containing Ir and located on the uppermost layer. The overall thickness of the lower electrode 42 is not particularly limited, and is, for example, 100 nm. When the thickness of the adhesion layer before firing is d0, the thickness of the third layer 423 is d1, the thickness of the second layer is d2, the thickness of the first layer is d3, and the thickness of the entire lower electrode after firing is dT. ,
dT = 3.6 × d0 + 2.4 × d1 + 0.8 × d2 + 2.3 × d3
Is preferably satisfied.
[0023]
A Ti nucleus layer (not shown) is formed on the lower electrode 42. The Ti nucleus has a thickness of 4 nm or more and 6 nm or less.
[0024]
The piezoelectric thin film 43 is a ferroelectric material composed of ordinary piezoelectric ceramic crystals, and is preferably a ferroelectric piezoelectric material such as lead zirconate titanate (PZT) or a niobium oxide or an oxide thereof. It is formed by adding a metal oxide such as nickel or magnesium oxide. The composition of the piezoelectric thin film 43 is appropriately selected in consideration of the characteristics, application, and the like of the piezoelectric element. Specifically, lead titanate (PbTiO ₃ ), lead zirconate titanate (Pb (Zr, Ti) O ₃ ), lead zirconate (PbZrO ₃ ), lanthanum lead titanate ((Pb, La), TiO ₃ ), Lanthanum lead zirconate titanate ((Pb, La) (Zr, Ti) O ₃ ), or lead zirconium titanate magnesium niobate (Pb (Zr, Ti) (Mg, Nb) O ₃ ) is preferred. Used. In addition, a film having excellent piezoelectric characteristics can be obtained by appropriately adding niobium (Nb) to lead titanate or lead zirconate.
[0025]
The degree of 100-plane orientation of the piezoelectric thin film 43 measured by the X-ray diffraction wide-angle method is 40% or more and 70% or less. The degree of orientation in the 110 plane is 10% or less, and the degree of orientation in the 111 plane is the remainder.
[0026]
The thickness of the piezoelectric thin film 43 needs to be suppressed to a level that does not cause cracks in the manufacturing process, and on the other hand, must be large enough to exhibit sufficient displacement characteristics, for example, 1500 nm.
[0027]
The upper electrode 44 is an electrode paired with the lower electrode 42, and is preferably made of Pt or Ir. The thickness of the upper electrode 44 is preferably about 50 nm.
[0028]
FIG. 4 is a perspective partial cross-sectional view showing a structure of a main part of the ink jet recording head of the present invention.
[0029]
As shown in FIG. 4, the ink jet recording head includes a nozzle plate 10, a pressure chamber substrate 20, a vibration plate 30, and a piezoelectric element 40.
[0030]
The pressure chamber substrate 20 includes a pressure chamber (cavity) 21, a side wall 22, a reservoir 23, and a supply port 24. The pressure chamber 21 is formed as a space for storing ink or the like by discharging a substrate such as silicon by etching. The side wall 22 is formed to partition the pressure chamber 21. The reservoir 23 is a flow path for filling the pressure chambers 21 with ink in common. The supply port 24 is formed so that ink can be introduced from the reservoir 23 into each of the pressure chambers 21.
[0031]
The nozzle plate 10 is bonded to one surface of the pressure chamber substrate 20 such that the nozzles 11 are arranged at positions corresponding to the respective pressure chambers 21 provided on the pressure chamber substrate 20.
[0032]
The vibration plate 30 is formed by laminating the oxide film 31 and the ZrO ₂ film 32 as described above. The piezoelectric element 40 of the present invention is provided on the diaphragm 30 as a piezoelectric actuator. A piezoelectric element 40 having the layer structure shown in FIG. 1 is provided at a position on the vibration plate 30 corresponding to each pressure chamber 21. The vibration plate 30 is provided with an ink tank port 35 so that ink stored in an ink tank (not shown) can be supplied into the pressure chamber substrate 20.
[0033]
The pressure chamber substrate 20 provided with the nozzle plate 10 and the vibration plate 30 is further housed in a casing (not shown) to form an ink jet recording head.
[0034]
In the above configuration, when a voltage is applied between the lower electrode 42 and the upper electrode 44 of the piezoelectric element 40 and the piezoelectric element 40 is distorted, the diaphragm 30 is deformed in response to the distortion. Due to the deformation, pressure is applied to the ink in the pressure chamber 21, and ink droplets are ejected from the nozzle 11.
[0035]
FIG. 5 is a perspective view illustrating the structure of the printer 100 according to the present embodiment. As shown in FIG. 5, in the printer 100, an ink jet recording head 1, a tray 3, a discharge port 4, a paper feed mechanism 6, a control circuit 8, an operation panel 9, and the like of the present invention, which are printing means, are provided in a printer main body 2. Is provided.
[0036]
The tray 3 is configured so that the paper 5 before printing can be supplied to the paper feed mechanism 6. The control circuit 8 causes the paper feed mechanism 6 to convey the paper 5 and prints the ink jet recording head 1 based on control from the operation panel 9 or print information supplied from the outside. The print signal Sh is output. The paper feed mechanism 6 includes rollers 601 and 602 that take in the paper 5, a motor 600 that drives them, and the like, and can take in the paper 5 into the main body 2 based on a paper feed signal Sd. The ink jet recording head 1 is configured to be able to move across the paper 5 supplied by the paper feeding mechanism 6, and when a print signal Sh is supplied from the control circuit 8, the piezoelectric element 40 is deformed. The ink is ejected and printing can be performed on the paper 5. The discharge port 4 is an outlet from which the printed paper 5 can be discharged.
[0037]
(Embodiment 2)
FIG. 2 is an enlarged sectional view of a layer structure of a piezoelectric element portion of an ink jet recording head according to a second embodiment of the present invention.
[0038]
In the present embodiment, the lower electrode 42 has a thickness of 30% or more and 50% or less with respect to the thickness of the lower electrode 42, and includes a second layer (lowest layer) 426 containing Pt and a first layer 426 containing Ir. The second embodiment differs from the first embodiment in that the second embodiment includes a layer (uppermost layer) 427.
[0039]
(Embodiment 3)
FIG. 3 is a sectional view of a layer structure in which a piezoelectric element portion of an ink jet recording head according to a third embodiment of the present invention is enlarged.
[0040]
In the present embodiment, the lower electrode 42 has a second layer (lowermost layer) 428 containing Ir and a first layer containing Pt having a thickness of 20% or more and 40% or less with respect to the thickness of the lower electrode 42. The second embodiment differs from the first embodiment in that the second embodiment includes a layer (uppermost layer) 429.
[0041]
(Production method)
Next, a method for manufacturing the piezoelectric element of the present invention will be described. 6 and 7 are schematic sectional views illustrating a method for manufacturing the piezoelectric element and the ink jet recording head of the present invention.
[0042]
Oxide film forming step (S1)
In this step, high-temperature treatment is performed in an oxidizing atmosphere containing oxygen or water vapor to form an oxide film 31 made of silicon oxide (SiO ₂ ). In this step, a CVD method can be used in addition to a commonly used thermal oxidation method.
[0043]
Step of forming ZrO ₂ film (S2)
In this step, a ZrO ₂ film 32 is formed on the oxide film 31 on the pressure chamber substrate 20. The ZrO ₂ film 32 is obtained by subjecting a Zr layer formed by a sputtering method or a vacuum evaporation method to a high temperature treatment in an oxygen atmosphere.
[0044]
Step of forming lower electrode (S3)
In the lower electrode according to the first embodiment, the step of forming the third layer 423 containing Ir on the ZrO ₂ film 32 and the step of forming 30% on the third layer with respect to the thickness of the lower electrode 42 The method includes a step of forming a second layer 424 having a thickness of 50% or less and containing Pt, and a step of forming a first layer 425 containing Ir on the second layer.
[0045]
In the lower electrode according to the second embodiment, a second layer 426 including Pt, having a thickness of 30% or more and 50% or less with respect to the thickness of the lower electrode 42, is formed on the ZrO ₂ film 32. And forming a first layer 424 containing Ir on the second layer.
[0046]
In the lower electrode according to the third embodiment, a step of forming a second layer 428 containing Ir on the ZrO ₂ film 32 and a step of forming 20% on the second layer with respect to the thickness of the lower electrode 42 Forming a first layer 429 having a thickness of not less than 40% and containing Pt.
[0047]
Each of the layers 423 to 429 is formed by depositing Ir or Pt on the ZrO ₂ film 32 by a sputtering method or the like. Prior to the formation of the lower electrode 42, an adhesion layer (not shown) made of titanium or chromium may be formed by a sputtering method or a vacuum evaporation method.
[0048]
Step of forming Ti nucleus (layer) This step is a step of forming a titanium crystal (not shown) in an island shape on the lower electrode 42 by a sputtering method or the like. The Ti nucleus (layer) is formed because, by growing PZT with a titanium crystal as a nucleus, crystal growth occurs from the lower electrode side, and a dense columnar crystal is obtained.
[0049]
Step of Forming Piezoelectric Precursor Film (S4)
This step is a step of forming the piezoelectric precursor film 43 'by the sol-gel method.
[0050]
First, a sol composed of an organic metal alkoxide solution is applied onto a Ti nucleus by an application method such as spin coating. Next, drying is performed at a constant temperature for a predetermined time, and the solvent is evaporated. After drying, degreasing is further performed at a predetermined high temperature in an air atmosphere for a certain period of time, and an organic ligand coordinated to the metal is thermally decomposed to obtain a metal oxide. These steps of coating, drying and degreasing are repeated a predetermined number of times, for example, four times or more, and four or more piezoelectric precursor films are laminated. By these drying and degreasing treatments, the metal alkoxide and the acetate in the solution form a metal, oxygen and metal network through thermal decomposition of the ligand.
[0051]
Firing step (S5)
In this step, the piezoelectric precursor film 43 'is formed and then fired to crystallize the piezoelectric precursor film. By this baking, the piezoelectric precursor film 43 ′ has a perovskite crystal structure formed from the precursor in an amorphous state, and changes to a thin film exhibiting an electromechanical conversion effect. It becomes a piezoelectric thin film of 40% or more and 70% or less.
[0052]
Upper electrode forming step (S6)
Finally, an upper electrode 44 is formed on the piezoelectric thin film 43 by an electron beam evaporation method or a sputtering method.
[0053]
If the piezoelectric element 40 obtained in the above steps is etched and shaped into a shape suitable for the place of use and manufactured so that a voltage can be applied between the upper and lower electrodes, the piezoelectric element 40 can be operated as the piezoelectric element of the present invention. It is possible.
[0054]
The process of etching the obtained piezoelectric element 40 so as to be compatible with the ink jet recording head and forming it into a shape as a piezoelectric element will be described below with reference to FIG.
[0055]
Piezoelectric element forming step (S7)
First, the piezoelectric element 40 is masked into a shape adapted to each pressure chamber 21, and the periphery thereof is etched. Specifically, first, a resist material having a uniform thickness is applied on the upper electrode using a method such as a spinner method or a spray method. Next, a mask is formed in the shape of the piezoelectric element, and then exposed and developed to form a resist pattern on the upper electrode 44. The upper electrode 44, the piezoelectric thin film 43, and the lower electrode 42 are removed by etching by applying ion milling or dry etching method or the like which is generally used, and each piezoelectric element 40 is formed.
[0056]
Pressure chamber forming step (S8)
Next, the other surface of the pressure chamber substrate 20 on which the piezoelectric element 40 is formed is subjected to anisotropic etching using an active gas such as anisotropic etching or parallel plate type reactive ion etching. To form The portion left without being etched becomes the side wall 22.
[0057]
Nozzle plate bonding process (S9)
Finally, the nozzle plate 10 is attached to the etched pressure chamber substrate 20 with an adhesive. At the time of bonding, the nozzles 11 are aligned so as to be arranged in the respective spaces of the pressure chambers 21. The pressure chamber substrate 20 to which the nozzle plate 10 is attached is attached to a housing (not shown), and the ink jet recording head 1 is completed.
[0058]
(Example)
Some piezoelectric elements according to the manufacturing method of the first embodiment are manufactured by variously changing the ratio of the thickness of the Pt layer to the total thickness of the lower electrode, and as a comparative example, a ratio other than that shown in the above embodiment is used. Some piezoelectric elements were also manufactured depending on the ratio.
[0059]
FIG. 8 is a graph showing the relationship between the degree of 100-plane orientation and the piezoelectric constant d31 of the resultant piezoelectric element. In particular, the piezoelectric constant d31 is measured at both a high frequency (14 kHz, measured using an inkjet head) and a low frequency (DC drive, measured using a cantilever). In FIG. 8, when the degree of orientation in the 100 plane is small, it indicates that the degree of orientation in the 111 plane is large.
[0060]
As shown in FIG. 8, the piezoelectric multiplier d31 increases as the 111-plane orientation increases in low-frequency driving, but the 100-plane orientation increases from 40% to 70% in high-frequency driving such as used in an inkjet head. At times, it can be seen that suitable piezoelectric characteristics can be obtained. The piezoelectric element having such a degree of orientation was manufactured when the thickness of the Pt layer was 30 to 50% of the total thickness of the lower electrode.
[0061]
The measurement of the piezoelectric constant d31 was obtained from the displacement at the time of applying a voltage. In addition, the “degree of 100-plane orientation” referred to in the present application means that when the diffraction intensity of the peak (2θ) corresponding to the XYZ plane when CuKα rays are used in the X-ray diffraction wide-angle method is I (XYZ), I (XYZ) 100) to the sum of I (100), I (110) and I (111).
[0062]
(Other modifications)
The present invention can be applied in various modifications without depending on the above embodiment. For example, the piezoelectric element manufactured by the present invention is not limited to the piezoelectric element of the above-mentioned ink jet recording head, but also includes a nonvolatile semiconductor memory device, a thin film capacitor, a pyroelectric detector, a sensor, a surface acoustic wave optical waveguide, and an optical memory. It can be applied to the manufacture of ferroelectric devices, such as devices, spatial light modulators, frequency doublers for diode lasers, dielectric devices, pyroelectric devices, piezoelectric devices, and electro-optical devices.
[0063]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, the 100-plane orientation degree of a piezoelectric thin film can be obtained stably with good reproducibility. As a result, it is possible to obtain the ratio between the degree of 100-plane orientation and the degree of 111-plane orientation of the piezoelectric thin film with good reproducibility. Accordingly, it is possible to provide a piezoelectric element having stable and high piezoelectric characteristics at both high frequency and low frequency, and an ink jet recording head, a printer and a method of manufacturing the piezoelectric element using the same.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a piezoelectric element according to a first embodiment. FIG. 2 is a cross-sectional view of a piezoelectric element according to a second embodiment. FIG. 3 is a cross-sectional view of a piezoelectric element according to a third embodiment. FIG. 5 is a perspective view showing the structure of a main part of the printer. FIG. 5 is a perspective view showing the structure of a printer using the ink jet recording head of the present invention. FIG. 6 shows the method of manufacturing the ink jet recording head of the present invention. FIG. 7 is a schematic cross-sectional view showing a method of manufacturing the ink jet recording head of the present invention. FIG. 8 is a diagram showing the relationship between the degree of 100 plane orientation and the piezoelectric constant d31. Diagram showing the relationship with the thickness of the nucleus
Reference Signs List 20 pressure chamber substrate 30 diaphragm 31 oxide film 32 ZrO ₂ film 40 piezoelectric element 42 lower electrode 423 third layer (Ir)
424 Second layer (Pt)
425 First layer (Ir)
426 Second layer (Pt)
427 First layer (Ir)
428 Second layer (Ir)
429 First layer (Pt)
43 piezoelectric thin film 44 upper electrode

Claims (11)

A lower electrode formed on the ZrO ₂ film, a Ti layer formed on the lower electrode, a piezoelectric film formed on the Ti layer, and an upper electrode formed on the piezoelectric film. A piezoelectric element comprising:
A piezoelectric element, wherein the piezoelectric film has a degree of 100 plane orientation measured by an X-ray diffraction wide angle method of 40% or more and 70% or less. The piezoelectric element according to claim 1,
The piezoelectric element is characterized in that the piezoelectric film has a 110-plane orientation measured by an X-ray diffraction wide-angle method of 10% or less and a 111-plane orientation remaining. The piezoelectric element according to claim 1,
The lower electrode includes at least a first layer located on the uppermost layer and containing Ir, and a second layer located on the next layer and containing Pt, and the thickness of the second layer is the thickness of the entire lower electrode. 30% or more and 50% or less,
A piezoelectric element, wherein a Ti layer having a thickness of 4 nm or more and 6 nm or less is formed on the lower electrode, and a piezoelectric film is formed on the Ti layer. The piezoelectric element according to claim 3, wherein
The piezoelectric element according to claim 1, wherein the lower electrode includes a third layer that is located next to the second layer and is the lowermost layer of the lower electrode and contains Ir. The piezoelectric element according to claim 3, wherein
The piezoelectric element, wherein the second layer containing Pt is the lowermost layer among the lower electrodes. The piezoelectric element according to claim 1,
The lower electrode includes at least a first layer containing Pt located on the uppermost layer and a second layer containing Ir on the next layer, and the thickness of the first layer is the thickness of the entire lower electrode. 20% or more and 40% or less,
A piezoelectric element, wherein a Ti layer having a thickness of 4 nm or more and 6 nm or less is formed on the lower electrode, and a piezoelectric film is formed on the Ti layer. The piezoelectric element according to claim 6,
The piezoelectric element, wherein the second layer containing Ir is the lowermost layer among the lower electrodes. 8. An ink jet recording head, wherein the piezoelectric element according to claim 1 is provided as a piezoelectric actuator on a vibration plate on which the piezoelectric element is mounted. A printer comprising the ink jet recording head according to claim 8 as printing means. Forming a ZrO ₂ film on the substrate;
Forming a lower electrode on the ZrO ₂ film;
Forming a Ti layer having a thickness of 4 nm or more and 6 nm or less on the lower electrode;
Forming a piezoelectric precursor film on the Ti layer;
And a firing step, comprising:
The lower electrode includes at least a first layer located on the uppermost layer and containing Ir, and a second layer located on the next layer and containing Pt, and the thickness of the second layer is the thickness of the entire lower electrode. 30% or more and 50% or less,
The step of forming the lower electrode,
Forming the second layer containing Pt;
Forming the first layer containing Ir on the second layer. Forming a ZrO ₂ film on the substrate;
Forming a lower electrode on the ZrO ₂ film;
Forming a Ti layer having a thickness of 4 nm or more and 6 nm or less on the lower electrode;
Forming a piezoelectric precursor film on the Ti layer;
And a firing step, comprising:
The lower electrode includes at least a first layer containing Pt located on the uppermost layer and a second layer containing Ir on the next layer, and the thickness of the first layer is the thickness of the entire lower electrode. 20% or more and 40% or less,
The step of forming the lower electrode,
Forming the second layer containing Ir;
Forming the first layer containing Pt on the second layer.

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