JP2003188432A - Piezo-electric device, its manufacturing method, ink jet head and ink jet recording device equipped therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly reliable piezo-electric device and its manufacturing method which has a high piezo-electric constant (d<SB>31</SB>) and good reproducibility of piezo-electric characteristics with minimum variations. <P>SOLUTION: An adhesion layer 2 made of oxidizing metal is laid on a board 1. A first electrode layer 3 made of non-oxidizing metal is laid on the layer 2. A seed 5 made of oxide of the element of the adhesion layer and distributed insularly on the first electrode layer is laid on the first electrode layer. An orientation control layer 6 made of oxide is laid on the first electrode on which the seed is formed. A piezo-electric layer 7 made of oxide is laid on the layer 6. A second electrode layer 8 is laid on the piezo-electric layer. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a microsensor,
The present invention relates to a piezoelectric element used for a microactuator, a micropump, a microspeaker, an ink jet head and the like, a method for manufacturing the same, and an ink jet recording apparatus having the ink jet head and the ink jet head as a printing means.

[0002]

2. Description of the Related Art In recent years, there has been a strong demand for miniaturization, power saving, and high speed driving of electronic devices equipped with piezoelectric elements. In order to meet the demand, a piezoelectric element that uses a piezoelectric thin film having a volume significantly smaller than that of a sintered body that has been widely used has been used. As a conventional piezoelectric element of this type, as shown in a partial cross-sectional view of FIG. 6, an electrode lower layer 101 made of titanium and platinum is provided on an insulating film 100, and an electrode upper layer made of platinum is provided thereon to form a lower electrode. 103, and a piezoelectric thin film layer on the lower electrode 103
There is one in which 104 is provided and the upper electrode 105 is provided on the piezoelectric thin film to prevent the occurrence of cracks in the piezoelectric thin film 104 (for example, Japanese Patent Laid-Open No. 2000-252544).

[0003]

However, when a piezoelectric thin film of an oxide such as lead zirconate titanate (hereinafter referred to as PZT) is formed on an electrode made of a non-oxidizing metal as in the above-mentioned conventional technique, High piezoelectric constant (d ₃₁ ) is obtained (00
There was a problem that the piezoelectric thin film in which the crystal plane of 1) was preferentially oriented could not be formed with good reproducibility. In addition, there is a problem that strong adhesion cannot be obtained between the electrode made of non-oxidizing metal and the piezoelectric thin film of oxide. Therefore, when mass-producing a piezoelectric element having a conventional configuration, there were problems that a high piezoelectric constant (d ₃₁ ) could not be obtained, the reproducibility of piezoelectric characteristics was poor, there was a large variation, and the reliability was low. Further, the ink jet head provided with the conventional piezoelectric element has a low ink ejection capability, and when mass-produced, there is a problem in that the reproducibility of the characteristics is lacking, the variation is large, and the reliability is low. Further, the conventional ink jet type recording apparatus provided with the ink jet head has a problem that the variation in recording on the recording medium is large and the reliability is low. The present invention solves the above-mentioned problems in the prior art, and has a high piezoelectric constant (d ₃₁ ), good reproducibility of piezoelectric characteristics, small variation, and high reliability, and a method for manufacturing the same. The purpose is to provide. It is another object of the present invention to provide a high performance ink jet head and an ink jet type recording apparatus.

[0004]

In order to achieve the above object, a piezoelectric element of the present invention is provided with an adhesion layer made of an oxidizing metal on a substrate and a non-oxidizing metal made on the adhesion layer.
A first electrode layer is provided, and a seed made of an oxide of the element of the adhesion layer distributed in an island shape is provided on the first electrode layer, and the seed is formed on the first electrode layer. An alignment control layer made of an oxide is provided, a piezoelectric layer made of an oxide is provided on the alignment control layer, and a second electrode layer is provided on the piezoelectric layer.

According to the structure of the piezoelectric element, by providing a seed made of an oxide, the adhesion between the first electrode layer and the orientation control layer made of an oxide is strengthened, and the orientation control layer and the oxide are made. It is possible to obtain strong adhesiveness also with the piezoelectric layer made of.

Further, the piezoelectric layer is made of (00
Since the crystal plane of 1) can be preferentially oriented, a piezoelectric element having a high piezoelectric constant (d ₃₁ ) and having high reproducibility, variation and reliability of piezoelectric characteristics can be realized.

The adhesion layer in the structure of the piezoelectric element is preferably at least one selected from the group consisting of titanium, iron, cobalt, nickel and manganese. The thickness of the adhesive layer is preferably 0.005 μm to 0.2 μm. Also,
The electrode layer of 1 is preferably one or more selected from the group consisting of platinum, iridium, rhodium and ruthenium. The seed is preferably one or more selected from the group consisting of titanium oxide, iron oxide, cobalt oxide, nickel oxide and manganese oxide. Then, the shield for the first electrode layer
It is preferable that the proportion of the metal is 0.1 atomic% to 15 atomic%. Further, the orientation control layer, lead lanthanum titanate or lead lanthanum titanate is added one or more selected from the group of magnesium or manganese, further lead is 5 atom% than the stoichiometric composition of lead lanthanum titanate. To 30 atomic% excess is preferable. The thickness of the orientation control layer is preferably 0.005 μm to 0.2 μm.
The piezoelectric layer is made of lead zirconate titanate, lead zirconate titanate, magnesium (Mg), niobium (N
It is preferable that one or more kinds selected from the group of b) and zinc (Zn) are added. And the thickness of the piezoelectric layer is 1 μm
To 10 μm is preferred.

In the method of manufacturing a piezoelectric element according to the present invention, an adhesion layer made of an oxidizing metal is formed on a substrate in a non-oxidizing atmosphere, and a first electrode layer made of a non-oxidizing metal is formed on the adhesion layer. Formed in a non-oxidizing atmosphere, the adhesion layer and the first
The electrode layer of 1 is annealed in an oxidizing atmosphere to diffuse the elements of the adhesion layer on the first electrode layer and distribute them in an island shape, and the elements of the adhesion layer are oxidized to form a seed. An orientation control layer made of an oxide is formed on the seed electrode-formed first electrode layer, a piezoelectric body layer made of an oxide is formed on the orientation control layer, and a first layer is formed on the piezoelectric body layer. It is characterized in that two electrode layers are formed.

According to the method for manufacturing a piezoelectric element of the present invention, the adhesion between the first electrode layer and the orientation control layer made of oxide is strengthened by forming the seed made of oxide,
It is possible to obtain strong adhesion between the orientation control layer and the piezoelectric layer, and the orientation control layer allows the piezoelectric layer to be preferentially oriented to the (001) crystal plane, so that a high piezoelectric constant (d ₃₁ ). It is possible to manufacture a piezoelectric element having the following characteristics, good reproducibility of piezoelectric characteristics, small variation, and good reliability.

In the ink jet head according to the present invention, a vibration plate is provided on one surface of a substrate, an adhesion layer made of an oxidizing metal is provided on the vibration plate, and a non-oxidizing metal is made on the adhesion layer. A first electrode layer is provided, and a seed made of an oxide of an element of the adhesion layer distributed in an island shape is provided on the first electrode layer, and the seed is formed on the first electrode layer. An orientation control layer made of an oxide is provided on the piezoelectric layer, an piezoelectric layer made of an oxide is provided on the orientation control layer, a second electrode layer is provided on the piezoelectric layer, and a partition is formed on the other surface of the substrate. It is characterized in that a piezoelectric element provided with an enclosed pressure chamber, a partition wall of the piezoelectric element, and an ink jet head main body having an ink ejection port and a pressure chamber are joined.

According to the constitution of the ink jet head of the present invention, the adhesion between the first electrode layer and the alignment control layer is strengthened by the oxide seed, and both the alignment control layer and the piezoelectric layer are formed. It becomes possible to obtain strong adhesiveness, and the orientation control layer allows the piezoelectric layer to be preferentially oriented to the (001) crystal plane, so that it has a high piezoelectric constant (d ₃₁ ).
It is possible to realize an ink jet head having good reproducibility of piezoelectric characteristics, small variation, and good reliability.

Further, since the piezoelectric layer having a high piezoelectric constant (d ₃₁ ) is provided, an ink jet head having a high ink ejection capability can be realized.

Further, since the ink jet head of the present invention has a high ink ejection capability, the margin for adjusting the power supply voltage can be made large, so that the variation in the ink ejection amount can be easily controlled.

Further, in the constitution of the ink jet head of the present invention, the adhesion layer made of an oxidizing metal is titanium.
1 selected from the group of iron, cobalt, nickel and manganese
It is preferably at least one species. And the thickness of the adhesion layer is 0.
It is preferably 005 μm to 0.2 μm. The first electrode layer made of a non-oxidizing metal is preferably one or more selected from the group consisting of platinum, iridium, rhodium and ruthenium. The seed is preferably one or more selected from the group consisting of titanium oxide, iron oxide, cobalt oxide, nickel oxide and manganese oxide. The ratio of the seed to the first electrode layer is preferably 0.1 atom% to 15 atom%. The orientation control layer is made of lead lanthanum titanate or lead lanthanum titanate to which one or more kinds selected from the group of magnesium and manganese are added, and the lead content is 5% or more than that of lead lanthanum titanate. It is preferable that the composition contains at least 30 atomic% in excess. The thickness of the orientation control layer is preferably 0.005 μm to 0.2 μm. The piezoelectric layer is selected from the group consisting of lead zirconate titanate or lead zirconate titanate, magnesium (Mg), niobium (Nb), and zinc (Zn).
It is preferable that one or more kinds are added. The thickness of the piezoelectric layer is preferably 1 μm to 10 μm.

In the method for producing an ink jet head of the present invention, a vibration plate is formed on one surface of a substrate, and an adhesion layer made of an oxidizing metal is formed on the vibration plate in a non-oxidizing atmosphere. A first electrode layer made of a non-oxidizing metal is formed on the adhesion layer in a non-oxidizing atmosphere, and the adhesion layer and the first electrode layer are formed.
The electrode layer of 1 is annealed in a non-oxidizing atmosphere to diffuse the elements of the adhesion layer on the first electrode layer and distribute them in an island shape, and the elements of the adhesion layer are oxidized in an oxidizing atmosphere. A seed is formed, an orientation control layer is formed on the first electrode layer on which the seed is formed, a piezoelectric layer is formed on the orientation control layer, and a second layer is formed on the piezoelectric layer. An ink jet head main body provided with an electrode layer, a pressure chamber surrounded by a partition wall on the other surface of the substrate to form a piezoelectric element, and the partition wall of the piezoelectric element, an ink ejection port and a pressure chamber. It is characterized by joining and.

According to the method for producing an ink jet head of the present invention, the adhesion between the first electrode layer and the orientation control layer is strengthened by the oxide seed, and both the orientation control layer and the piezoelectric layer are formed. Since it is possible to obtain a strong adhesiveness, it is possible to manufacture an ink jet head having good reproducibility of piezoelectric characteristics, small variation, and good reliability.

The structure of the ink jet recording apparatus according to the present invention comprises an ink jet head of the present invention, an ink jet head transfer means for moving the ink jet head in the width direction of a recording medium, and an ink jet head moving direction substantially in the transfer direction of the ink jet head. And a recording medium transfer means for transferring the recording medium in a vertical direction. According to this ink jet type recording apparatus, by using an ink jet head having high ink ejection capability and high reliability, it is possible to realize a highly reliable ink jet type recording apparatus with little variation in recording on the recording medium. can do.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a diagram showing a method of manufacturing a piezoelectric element of this embodiment. In the figure (a), 1 is silicon (Si) having a thickness of 0.2 mm, a width of 20 mm, and a length of 20 mm.
The adhesion layer 2 made of titanium (Ti) which is an oxidizing metal and has a thickness of 0.01 μm was formed on the substrate. The adhesion layer was formed by sputtering the substrate at 400 ° C. for 5 minutes in 1 Pa of argon gas in a non-oxidizing atmosphere. Next, a first electrode layer 3 made of non-oxidizing metal platinum (Pt) having a thickness of 0.2 μm was formed on the adhesion layer. This first electrode layer was formed by performing sputtering at room temperature in an argon gas of 1 Pa for 30 minutes. Next figure
As shown in 1 (b) and (c), the stack consisting of the substrate, the adhesion layer, and the first electrode layer was oxidized with 0.5 Pa of argon-oxygen gas (gas volume ratio Ar: O2 = 10: 2). 300 ℃ in the atmosphere
After annealing for 30 minutes, titanium was diffused in platinum and distributed in an island shape to form an island-shaped seed 5 composed of titanium oxide (TiOx). In this case, the seed ratio (Ti / Pt) on the surface of the first electrode layer was determined by the secondary ion mass spectrometry (S
It was 1.5 atom% when measured by IMS). Next, as shown in FIG. 1 (d), on the first electrode layer having a seed formed on the surface, a composition of 0.8 An orientation control layer 6 made of lead lanthanum titanate of Pb _0.9 La _0.1 ) TiO ₃ + 0.2PbO was formed. This orientation control layer was heated to 560 ° C and the substrate was heated to 560 ° C with 0.3 Pa argon-
In oxygen gas (gas volume ratio Ar: O2 = 19: 1), 0.7 (Pb
_0.9 La _{0. 1)} by using a target of the composition of TiO ₃ + 0.3PbO 10
It was formed by performing sputtering for minutes. This orientation control layer has a perovskite crystal structure in which the (001) plane is preferentially oriented. Next, on the orientation control layer, while heating the substrate to 600 ° C., 0.3 Pa of argon-oxygen gas (gas volume ratio Ar: O 2
= 19: 1) and the thickness is 2.5 after sputtering for 2 hours.
A piezoelectric layer 7 having a perovskite type crystal structure made of lead zirconate titanate (PbZr0.53Ti0.47O3) having a (001) plane with a preferential orientation of μm was formed. The degree of orientation of the (001) plane of this piezoelectric layer was 98% when measured by the X-ray diffraction method. Here, the degree of orientation is the ratio of the diffraction intensity of the (001) plane when the sum of the diffraction intensities of the (001) plane, the (110) plane and the (111) plane is 100. Next, a second electrode layer 7 made of platinum (Pt) having a thickness of 0.2 μm was formed on the piezoelectric layer. The width of each layer from 2 to 7 is 0.
100 pieces were formed on the substrate with a length of 2 mm and a length of 15 mm. In the piezoelectric element having the above structure, when an electric signal is applied between the first electrode layer and the second electrode layer, it is converted into a mechanical signal in the piezoelectric layer. The piezoelectric constant (d31) of the piezoelectric layer of this embodiment is −100.
The variation was pC / N in the range of ± 1.5%. The method for measuring the piezoelectric constant (d31) will be described later. Moreover, when an AC voltage of 100 V was applied to this piezoelectric element for 10 hours, 99% of the piezoelectric elements did not break down and showed high reliability. As described above, according to the piezoelectric element of the present embodiment, the adhesion of each layer is improved as compared with the comparative example described below, no crack is generated in the piezoelectric layer, and the (001) plane is Since the piezoelectric thin film with preferential orientation can be formed with good reproducibility, it has excellent reproducibility of characteristics even if it is mass-produced industrially, has less variation, and has improved reliability.

(Comparative Example 1) The same silicon (S
An adhesion layer made of titanium (Ti) having a thickness of 0.05 μm was formed on the substrate made of i). This adhesion layer was formed by sputtering the substrate at 400 ° C. in an argon gas of 1 Pa for 30 minutes for sputtering. Next, a first electrode layer made of platinum (Pt) having a thickness of 0.2 μm was formed on the adhesion layer. This first electrode layer was formed by performing sputtering at room temperature in an argon gas of 1 Pa for 30 minutes. Next, lead zirconate titanate (PbZr0.53Ti0.47) having a thickness of 2.5 μm was formed on the first electrode layer.
A piezoelectric layer made of O3) was formed. This piezoelectric layer was formed by sputtering the substrate in argon-oxygen gas (gas volume ratio Ar: O2 = 19: 1) of 0.3 Pa for 2 hours while heating the substrate to 600 ° C. Next, a second electrode layer made of platinum (Pt) having a thickness of 0.2 μm was formed on the piezoelectric layer. This first electrode layer was formed by performing sputtering at room temperature in an argon gas of 1 Pa for 30 minutes. The width of each layer is 0.2 mm,
The length was 15 mm and 100 pieces were formed on the substrate. The piezoelectric element of this comparative example is different from that of the first embodiment in that there is no seed made of an oxide on the first electrode and no alignment control layer is provided. The degree of orientation of the (001) plane of this piezoelectric layer is 30%,
In addition, it was a state in which a pyrochlore phase that did not exhibit piezoelectric characteristics was mixed, and the piezoelectric constant (d31) was in the range of -5 to -25 pC / N, resulting in large variation. In addition, this piezoelectric element
When an AC voltage of 0 V was applied, 95% was destroyed in 10 minutes.

(Comparative Example 2) The same silicon (S
An adhesion layer made of titanium (Ti) having a thickness of 0.05 μm was formed on the substrate made of i). This adhesion layer was formed by sputtering the substrate at 400 ° C. in an argon gas of 1 Pa for 30 minutes for sputtering. Next, a first electrode layer made of platinum (Pt) having a thickness of 0.2 μm was formed on the adhesion layer. This first electrode layer was formed by performing sputtering at room temperature in an argon gas of 1 Pa for 30 minutes. This substrate, adhesion layer, first
The laminated body consisting of the electrode layers of 0.5 to 300 ° C. in an oxidizing atmosphere of 0.5 Pa of argon-oxygen gas (gas volume ratio Ar: O ₂ = 10: 2).
After annealing for 30 minutes, titanium was diffused in platinum and distributed in an island shape to form an island-shaped seed 5 composed of titanium oxide (TiOx). In this case, the seed ratio (Ti / Pt) on the surface of the first electrode layer was determined by the secondary ion mass spectrometry (S
It was 1.7 atomic% when measured by IMS). Then on the surface
An orientation control layer made of lead lanthanum titanate having a composition (Pb _0.9 La _0.1 ) TiO ₃ with a lead content of stoichiometric composition was formed on the first electrode layer on which the lead was formed. This orientation control layer was heated to 560 ° C. while heating the substrate at 560 ° C. in argon-oxygen gas (gas volume ratio Ar: O2 = 19: 1) of 0.3 Pa (Pb _0.9
It was formed by performing sputtering for 10 minutes using a target having a composition of La _0.1 ) TiO ₃ . This orientation control layer is (00
1) The perovskite crystal structure had a low degree of orientation of 20%. Next, a piezoelectric layer made of lead zirconate titanate (PbZr0.53Ti0.47O3) having a thickness of 2.5 μm was formed on the orientation control layer. This piezoelectric layer was heated to 600 ℃ while the substrate was heated to 600 ℃.
It was formed by sputtering for 2 hours in 2 = 19: 1). Next, a second electrode layer made of platinum (Pt) having a thickness of 0.2 μm was formed on the piezoelectric layer. This first electrode layer was formed by performing sputtering at room temperature in an argon gas of 1 Pa for 30 minutes. Each layer had a width of 0.2 mm and a length of 15 mm, and 100 layers were formed on the substrate. The piezoelectric element of this comparative example is different from that of the first embodiment in that the orientation control layer does not have a lead-rich composition, and the orientation degree of the (001) plane of the orientation control film is as low as 20%. The degree of orientation of the (001) plane of this piezoelectric layer is 40%, and it is a state in which a pyrochlore phase that does not exhibit piezoelectric characteristics is mixed, and the piezoelectric constant (d31) is -10 to -45 pC / N, with large variations. It was the result. When 100V AC voltage was applied to this piezoelectric element, 75% of it was destroyed in 30 minutes.

(Embodiment 2) As shown in FIG. 2, the ink jet head of this embodiment is a diaphragm made of chromium having a thickness of 5 μm on one surface of the same silicon substrate 1 as used in Embodiment 1. 9 is formed by a sputtering method in an argon gas of 1 Pa at room temperature, then the same piezoelectric element as that of Embodiment 1 is formed on the diaphragm by the same manufacturing method, and then a silicon substrate is formed as shown in FIG. The other surface of the pressure chamber 11 is processed by the dry etching method and is surrounded by a partition wall 10 made of silicon.
By forming a, a piezoelectric element for an ink jet head was formed. Next, the partition wall of the piezoelectric element and the ink jet head main body 14 made of stainless steel having the ink ejection port 12 and the pressure chamber b13 were bonded with an adhesive (acrylic resin) 15. In such a configuration, when an electric signal is applied between the first electrode layer and the second electrode layer, a flexural vibration is generated by being converted into a mechanical signal by the piezoelectric element, and the flexural vibration causes ink in the pressure chamber to become ink. It is discharged from the discharge port. In the ink jet head of the present embodiment, 100 individual ink jet heads having the above-described structure are formed within an area of 20 mm × 20 mm. Even when the ink jet head was industrially mass-produced, the reproducibility and dispersion of the ejection performance were markedly improved as compared with the ink jet head provided with the piezoelectric element of the comparative example. In addition, there is no ink ejection failure even if an AC voltage of frequency 10 kHz and voltage 30 V is applied to each individual ink jet head for 10 days.
The discharge capacity also did not decrease.

(Embodiment 3) In the piezoelectric element of this embodiment, an adhesion layer made of nickel (Ni) and having a thickness of 0.01 μm is formed on the same substrate made of silicon as used in the first embodiment. This adhesion layer was formed by sputtering the substrate at 400 ° C. for 15 minutes in 1 Pa of argon gas in a non-oxidizing atmosphere. Next, a first electrode layer 3 made of iridium (Ir) which is a non-oxidizing metal and having a thickness of 0.15 μm was formed on the adhesion layer. This first electrode layer is 1 Pa at room temperature.
Was formed by performing sputtering for 30 minutes in Argon gas. Next, a laminated body composed of the substrate, the adhesion layer, and the first electrode layer was applied with 1.0 Pa of argon-oxygen gas (gas volume ratio Ar: O ₂ = 1.
0: 2) in an oxidizing atmosphere at 400 ° C for 30 minutes to diffuse nickel into iridium and distribute the islands to form islands of nickel oxide (NiOx). Formed. The seed ratio (Ni / Ir) in this case was 3 atomic%. Next, on the seed, the composition of 0.85 (Pb _0.9 L
An orientation control layer having a perovskite type crystal structure in which (001) plane was preferentially oriented was formed by adding 2 atom% of magnesium to lead lanthanum titanate of a _0.1 ) TiO ₃ + 0.15PbO. This orientation control layer was formed by performing sputtering for 20 minutes in an argon-oxygen gas (gas volume ratio Ar: O2 = 18: 2) of 0.3 Pa while heating the substrate at 600 ° C. A piezoelectric layer having a perovskite crystal structure of lead magnesium zirconium titanate niobate {0.6Pb (Mg1 / 3Nb2 / 3) O3 + 0.2PbZrO3 + 0.2PbTiO3} having a thickness of 3 μm was formed on the orientation control layer.
The degree of orientation of the (001) plane of this piezoelectric layer was 100% when measured by the X-ray diffraction method. Next, the thickness of 0.2μm on the piezoelectric layer
A second electrode layer made of platinum (Pt) was formed. Its sectional structure is the same as in Fig. 1 (d). The width of each layer above is 0.2m
100 pieces were formed on the substrate with m and length of 15 mm. In the piezoelectric element having the above structure, when an electric signal is applied between the first electrode layer and the second electrode layer, it is converted into a mechanical signal in the piezoelectric layer. The piezoelectric constant (d31) of this piezoelectric layer was −135 pC / N, and the variation was within ± 2.0%. An alternating voltage of 100 V was applied to this piezoelectric element for 10 hours.
Did not break down and showed high reliability. As described above, according to the piezoelectric element of the present embodiment, the adhesion of each layer is improved, no crack is generated in the piezoelectric layer, and the piezoelectric thin film in which the (001) plane is preferentially oriented has good reproducibility. Since it can be formed, it has excellent reproducibility of characteristics even if it is industrially mass-produced, and there is little variation,
Reliability has also improved.

(Embodiment 4) The ink jet head of the present embodiment is provided with the piezoelectric element of the third embodiment, and except that the diaphragm is made of aluminum oxide (Al2O3) having a thickness of 3 μm. It has the same structure as.
The diaphragm was formed by sputtering in argon-oxygen gas of 5 Pa while heating the substrate at 600 ° C. When an electric signal is applied between the first electrode layer and the second electrode layer of this ink jet head, the piezoelectric layer converts it into a mechanical signal to generate a flexural vibration, and the flexural vibration causes ink in the pressure chamber to ink. It is discharged from the discharge port. The ink jet head of the present embodiment has a piezoelectric layer having a large piezoelectric constant, and therefore has a higher ejection capability than the ink jet head of the second embodiment. In the ink jet head of this embodiment, 100 individual ink jet heads were formed within an area of 20 mm × 20 mm. Even when the ink jet head was industrially mass-produced, the reproducibility and dispersion of the ejection performance were markedly improved as compared with the ink jet head provided with the piezoelectric element of the comparative example. In addition, the frequency of 10kH is added to each individual ink jet head.
Even if an AC voltage of 30V was applied for 10 days, there was no ink ejection defect and the ejection performance was hardly reduced.

(Embodiment 5) The piezoelectric element of the present embodiment is
On a substrate made of stainless steel having a thickness of 0.5 mm, a width of 20 mm and a length of 20 mm, an adhesion layer made of manganese (Mn) which is an oxidizing metal and having a thickness of 0.1 μm was formed by a sputtering method.
This adhesion layer was formed by sputtering the substrate at 400 ° C. for 30 minutes in 1 Pa of argon gas in a non-oxidizing atmosphere. Next, a non-oxidizing metal of platinum-rhodium alloy (Pt-Rh) with a thickness of 0.2 μm was formed on the adhesion layer.
An electrode layer of 1 was formed. The first electrode layer was formed by performing sputtering for 40 minutes in argon gas of 1 Pa in a non-oxidizing atmosphere at room temperature. Next, the substrate, the adhesion layer, the
The laminated body consisting of 1 electrode layer was placed in an oxidizing atmosphere of 0.5 Pa of argon-oxygen gas (gas volume ratio Ar: O ₂ = 10: 2) at 300 ° C.
After annealing for 30 minutes, the manganese was diffused into the platinum-rhodium alloy and distributed in the form of islands to form island-shaped seeds of manganese oxide (MnOx). The seed ratio (Mn / Pt-Rh) in this case was 10 atomic%. Next, on the seed, the lead content of 0.05 μm in thickness was over the stoichiometric composition, and the composition of 0.7 (Pb _0.9 La _0.1 ) TiO ₃ +0.3 PbO in lead lanthanum titanate contained 5 atomic% An orientation control layer containing manganese (Mn) was formed. This orientation control layer was heated at 560 ° C. on the substrate and 0.3 Pa of argon-oxygen gas (gas volume ratio A
It was formed by performing sputtering for 20 minutes in r: O2 = 19: 1). This orientation control layer has a perovskite crystal structure in which the (001) plane is preferentially oriented. Then, on the orientation control layer, lead zirconium titanate zirconium titanate with a thickness of 3 μm {0.6P
A piezoelectric layer having a perovskite crystal structure made of b (Zn1 / 3Nb2 / 3) 0.2PbZrO3 + 0.2PbTiO3} was formed. The degree of orientation of the (001) plane of this piezoelectric layer was 95% when measured by the X-ray diffraction method. Next, on the piezoelectric layer, platinum (Pt) with a thickness of 0.2 μm
Was formed in argon gas at 1 Pa at room temperature. Its sectional structure is the same as in FIG. The width of each layer was 0.2 mm and the length was 15 mm, and 100 layers were formed on the substrate. In the piezoelectric element having the above structure, when an electric signal is applied between the first electrode layer and the second electrode layer, it is converted into a mechanical signal in the piezoelectric layer. The piezoelectric constant (d31) of this piezoelectric layer is -110pC.
/ N, and the variation was within ± 1.8%. Moreover, when an AC voltage of 100 V was applied to this piezoelectric element for 10 hours, 99% of the piezoelectric elements did not break down and showed high reliability. As described above, according to the piezoelectric element of the present embodiment, the adhesion of each layer is improved, no crack is generated in the piezoelectric layer, and (10
Since the piezoelectric layer in which the (0) plane is preferentially oriented can be formed with good reproducibility, the reproducibility of the characteristics is excellent, the variation is small, and the reliability is improved even when industrially mass-produced.

(Embodiment 6) The ink jet head of the present embodiment is provided with the piezoelectric element of the fifth embodiment, and except that the diaphragm is made of zirconium oxide (ZrO2) having a thickness of 3 μm. It has the same structure as. The diaphragm is 2 Pa of argon while heating the substrate to 600 ° C.
It was formed by a sputtering method in oxygen gas. In this configuration, when an electric signal is applied between the first electrode layer and the second electrode layer, the piezoelectric layer converts it into a mechanical signal to generate flexural vibration, and the flexural vibration causes ink in the pressure chamber to eject ink. It is discharged from the outlet. The ink jet head of the present embodiment is a single ink jet head having the above configuration.
100 pieces were formed within an area of 20 mm × 20 mm. Even if this ink jet head is industrially mass-produced, the reproducibility of discharge ability,
The variation was significantly improved as compared with the ink jet head provided with the piezoelectric element of the comparative example. In addition, even when an AC voltage having a frequency of 10 kHz and a voltage of 30 V was applied to each individual ink jet head for 10 days, there was no ink ejection failure and the ejection performance was hardly reduced.

(Embodiment 7) FIG. 4 is a schematic configuration diagram of an ink jet recording apparatus 16 provided with the ink jet head of the present invention. In the figure, 17 is an ink jet head, and ink droplets ejected from this ink jet head are made to land on a recording medium 18 such as paper for recording. The ink jet head is mounted on the ink jet head moving means 20 that moves in the main scanning direction X along the carriage axis 19, and the ink jet head moving means moves according to the reciprocating movement along the carriage axis 19. Reciprocates in the scanning direction X. Further, the ink jet type recording apparatus has a plurality of recording medium moving means 2 for moving the recording medium in the sub scanning direction Y which is substantially perpendicular to the main scanning direction X of the ink jet head.
With 1. The ink jet type recording apparatus of the present embodiment has a small variation in ejection ability, and even if it is driven for 10 days, there is no ejection failure of ink and high reliability is exhibited.

Next, the method for measuring the piezoelectric constant (d ₃₁ ) of the present invention will be described with reference to FIG.

In the figure, reference numeral 22 is a piezoelectric layer having a thickness of 2.5 μm for measuring the piezoelectric constant (d ₃₁ ), and a lower electrode 23 made of platinum having a thickness of 0.1 μm is provided on one surface thereof. ,
An upper electrode 24 made of aluminum having a thickness of 1.5 μm is provided on the other surface. The piezoelectric layer and the electrodes are processed into a T-shaped cantilever. The total length of the piezoelectric layer and the electrodes is 800 μm, and the wide part (width is 500 μm)
m) has a length of 300 μm and a narrow width (width is 50 μm).
The length of m) is 500 μm. The wide portion is fixed to a conductive support substrate (stainless steel substrate) 26 with a conductive adhesive (silver paste) 25.

A lead wire a27 is connected to the conductive support substrate which is electrically connected to the lower electrode. A lead wire b28 is connected to the upper electrode. When a voltage is applied between the lower electrode and the upper electrode via the lead wire a27 and the lead wire b28, the piezoelectric layer extends in the x direction in FIG. The amount of change ΔL (m) in the elongation of the piezoelectric layer is as follows: the applied voltage is E (V), the thickness of the piezoelectric layer is t (m), the length of the piezoelectric layer is L (m), The piezoelectric constant is d ₃₁ (pm / V)
Is expressed by the following (Equation 1).

[0031]

[Equation 1]

Here, the lower portion of the piezoelectric layer joined to the lower electrode having a small film thickness extends in the x direction, while the upper portion of the piezoelectric layer joined to the upper electrode having a large film thickness is The elongation displacement is suppressed by the thick upper electrode. As a result, the tip of the piezoelectric layer on the side opposite to the one end fixed to the conductive support substrate is displaced in the + z axis direction in FIG. Therefore,
When the application and removal of voltage is repeated at a constant frequency, the tip of the piezoelectric layer moves up and down in the z-axis direction with a predetermined displacement width. Then, the applied voltage and the displacement width of the tip of the piezoelectric layer were measured, and the piezoelectric constant (d ₃₁ ) was calculated from the above (Equation 1).

In the piezoelectric element and the ink jet head according to the present invention, the substrate has been described as silicon or stainless steel, but glass, crystallized glass or magnesium oxide may be used in place of these to obtain the same effect. Also, as the oxidizing metal, titanium, nickel,
Although manganese has been described, similar effects can be obtained by using iron or cobalt instead of manganese. Although titanium oxide, nickel oxide, and manganese oxide have been described as the seeds, the same effect can be obtained by using iron oxide or cobalt oxide instead of them. Although platinum, iridium and platinum rhodium have been described as non-oxidizing metals, the same effect can be obtained by using ruthenium instead of them.

Further, the ratio of the seed to the first electrode layer is limited to 0.1 atom% to 15 atom% by 0.1 atom%
If less than 15%, sufficient adhesion cannot be obtained and the (001) orientation of the crystal of the orientation control film formed on the seed deteriorates.If it exceeds 15 atom%, the adhesion decreases and the orientation formed on the seed. This is because the control film contains a pyrochlore phase other than the perovskite phase and the crystallinity deteriorates. In addition, the thickness of the adhesion layer was limited to 0.005 μm to 0.2 μm because when the thickness is less than 0.005 μm, sufficient adhesion cannot be obtained and the supply amount due to seed diffusion is insufficient, and when it exceeds 0.2 μm, the adhesion decreases. This is because the amount of seed supplied by the diffusion becomes excessive.

Further, the thickness of the orientation control film is changed from 0.005 μm to 0.
The limitation to 2 μm is that if it is less than 0.005 μm, an orientation control film having sufficient orientation of the (001) plane cannot be obtained, and if it exceeds 0.2 μm, it affects the crystal orientation of the (001) plane of the piezoelectric layer. This is because the difference is small and it is unnecessary in practice. Further, lead lanthanum titanate or lead lanthanum titanate for the orientation control film is selected from the group consisting of magnesium and manganese.
The composition limited to the composition containing 5% to 30 atomic% of lead in excess of the stoichiometric composition to the one containing more than one species is the orientation control when the excessive addition amount of lead is less than 5%. Of membrane
The degree of orientation of the (001) plane becomes low, the degree of orientation of the (001) plane of the piezoelectric layer becomes low, and the phase becomes a phase in which pyrochlore is mixed, and the piezoelectric constant decreases. This is because the degree of orientation of the (001) plane of the film becomes low, the degree of orientation of the (001) plane of the piezoelectric layer becomes low, and the phase becomes a phase in which lead oxide is mixed, and the piezoelectric constant decreases.

Further, the ratio of lanthanum in the orientation control film is
The ratio of lead / lanthanum excluding excess lead is atomic%
The case where the ratio is 90/10 has been described, but the same effect can be obtained if the composition has a lead / lanthanum ratio of 99.9 / 0.1 to 70/30 instead.

Further, the reason why the thickness of the piezoelectric layer is limited to 1 μm to 10 μm is that a large displacement amount cannot be obtained if the thickness is less than 1 μm. This is because it is difficult to form the second electrode layer flat, and as a result, it is difficult to stably manufacture a piezoelectric element with a small variation in displacement amount. When lead zirconate titanate is used for the piezoelectric layer, Zr / Ti
I explained that the ratio of is 53/47 in atomic% ratio,
Instead, if the composition has a Zr / Ti ratio between 30/70 and 70/30, the same effect can be obtained.

[0038]

According to the present invention, an adhesive layer made of an oxidizing metal is provided on a substrate, a first electrode layer made of a non-oxidizing metal is provided on the adhesive layer, and the first electrode layer is formed on the first electrode layer. Is provided with an island-shaped seed consisting of the oxide of the oxidizing metal,
An orientation control layer is provided on the first electrode layer on which the seed is formed, a piezoelectric layer is provided on the orientation control layer, and a second electrode layer is provided on the piezoelectric layer. Since the adhesion of each layer, the crystal structure of the piezoelectric layer and the preferentially oriented surface can be controlled, a piezoelectric element having good reproducibility, variation and reliability of piezoelectric characteristics even in industrial mass production and an ink jet head having the same Can be provided. Further, it is possible to provide a highly reliable ink jet type recording apparatus with little variation in ejection ability.

[Brief description of drawings]

1] Manufacturing process diagram of piezoelectric element

FIG. 2 is a sectional view of a piezoelectric element.

FIG. 3 is a sectional view of an ink jet head.

FIG. 4 is a schematic configuration diagram of an ink jet head type recording apparatus.

FIG. 5: Element for measuring piezoelectric constant (d ₃₁ ).

FIG. 6 is a sectional view of a conventional piezoelectric element.

[Explanation of symbols]

1 substrate 2 Adhesion layer 3 First electrode layer 4 Elements of adhesion layer 5 seeds 6 Alignment control layer 7 Piezoelectric layer 8 Second electrode layer 9 diaphragm 10 partitions 11 Pressure chamber a 12 Ink outlet 13 Pressure chamber b 14 Inkjet body 15 Adhesive 16 Inkjet recording device 17 Ink Jet Head 18 recording media 19 Carriage axis 20 Ink jet head moving means 21 recording medium moving means 22 Piezoelectric layer 23 Lower electrode 24 Upper electrode 25 Conductive adhesive (silver paste) 26 Conductive support substrate (stainless steel substrate) 27 Lead wire a 28 Lead wire b 100 insulating film 101 electrode lower layer 102 upper electrode layer 103 Lower electrode 104 Piezoelectric thin film layer 105 upper electrode

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01L 41/18 H01L 41/22 Z 41/22 41/08 L (72) Inventor Hideo Torii Kadoma City, Osaka Prefecture Daiji Kadoma 1006 Matsushita Electric Industrial Co., Ltd. (72) Inventor Akiko Kubo Osaka Kadoma City Kadoma 1006 Matsushita Electric Industrial Co., Ltd. F term (reference) 2C057 AF93 AG42 AG44 AP14 AP52 AP56 BA04 BA14

Claims (23)

[Claims] 1. An adhesion layer made of an oxidizing metal is provided on a substrate, a first electrode layer made of a non-oxidizing metal is provided on the adhesion layer, and the first electrode layer is distributed like islands on the first electrode layer. A seed made of an oxide of the element of the adhesion layer is provided, an orientation control layer made of an oxide is provided on the first electrode layer on which the seed is formed, and an orientation control layer made of an oxide is provided on the orientation control layer. A piezoelectric element in which a piezoelectric layer is provided and a second electrode layer is provided on the piezoelectric layer. 2. A step of forming an adhesion layer made of an oxidizing metal on a substrate in a non-oxidizing atmosphere, and a first electrode layer made of a non-oxidizing metal on the adhesion layer in a non-oxidizing atmosphere. The step of forming, the adhesion layer and the first electrode layer is annealed in an oxidizing atmosphere to distribute the elements of the adhesion layer in an island shape on the first electrode layer, and the elements of the adhesion layer are Oxidize and see
A step of forming an oxide, a step of forming an orientation control layer made of an oxide on the first electrode layer having the seed formed thereon, and a piezoelectric layer made of an oxide on the orientation control layer. 1. A method for manufacturing a piezoelectric element, comprising: a step; and a step of forming a second electrode layer on the piezoelectric layer. 3. A vibration plate is provided on one surface of a substrate, an adhesion layer made of an oxidizing metal is provided on the vibration plate, and a first electrode layer made of a non-oxidizing metal is provided on the adhesion layer. A seed comprising an oxide of the element of the adhesion layer distributed in an island shape is provided on the first electrode layer, and the seed is formed.
An orientation control layer made of an oxide is provided on the electrode layer of, a piezoelectric layer made of an oxide is provided on the orientation control layer, and a second electrode layer is provided on the piezoelectric layer. An ink jet head comprising a piezoelectric element having a pressure chamber surrounded by a partition wall, a partition wall of the piezoelectric element, and an ink jet head main body having an ink ejection port and a pressure chamber. 4. A step of forming a vibration plate on one surface of a substrate, a step of forming an adhesion layer made of an oxidizing metal on the vibration plate in a non-oxidizing atmosphere, and a step of forming the adhesion layer on the adhesion layer. A step of forming a first electrode layer made of a non-oxidizing metal in a non-oxidizing atmosphere, and annealing the adhesion layer and the first electrode layer in an oxidizing atmosphere to remove the elements of the adhesion layer 1 step of diffusing on the electrode layer to distribute in an island shape, oxidizing the elements of the adhesion layer to form a seed, and forming an orientation control layer made of an oxide on the seed And a step of forming a piezoelectric layer made of an oxide on the orientation control layer, a step of forming a second electrode layer on the piezoelectric layer, and surrounded by a partition wall on the other surface of the substrate. A step of forming a pressure chamber to form a piezoelectric element, a partition of the piezoelectric element, an ink discharge port, and an pressure chamber Ink jet head manufacturing method having a step of joining the Jietsutohetsudo body. 5. The inkjet head according to claim 3, inkjet head moving means for moving the inkjet head in the width direction of the recording medium, and moving the recording medium in a direction substantially perpendicular to the moving direction of the inkjet head. And an ink jet recording apparatus including a recording medium moving unit. 6. The adhesion layer made of an oxidizing metal is titanium,
1 selected from the group of iron, cobalt, nickel and manganese
2. The piezoelectric element according to claim 1, which is one or more kinds. 7. The adhesion layer made of an oxidizing metal is titanium,
1 selected from the group of iron, cobalt, nickel and manganese
4. The ink jet head according to claim 3, wherein the ink jet head is one or more kinds. 8. The first electrode layer made of a non-oxidizing metal,
2. The piezoelectric element according to claim 1, which is at least one selected from the group consisting of platinum, iridium, rhodium, and ruthenium. 9. The first electrode layer made of a non-oxidizing metal,
4. The ink jet head according to claim 3, which is at least one selected from the group consisting of platinum, iridium, rhodium and ruthenium. 10. The piezoelectric element according to claim 1, wherein the seed is one or more selected from the group consisting of titanium oxide, iron oxide, cobalt oxide, nickel oxide, and manganese oxide. 11. The ink jet head according to claim 3, wherein the seed is one or more selected from the group consisting of titanium oxide, iron oxide, cobalt oxide, nickel oxide and manganese oxide. 12. The orientation control layer comprises lead lanthanum titanate or lead lanthanum titanate to which one or more members selected from the group of magnesium and manganese are added, and the lead content is 5 atomic% to 30 atomic% more than the stoichiometric composition. The piezoelectric element according to claim 1, wherein the piezoelectric element has a composition that is contained in an excess of atomic%. 13. The orientation control layer comprises lead lanthanum titanate or lead lanthanum titanate to which one or more members selected from the group of magnesium and manganese are added, and lead is more than stoichiometric lead lanthanum titanate. 4. The ink jet head according to claim 3, wherein the composition also contains 5 atomic% to 30 atomic% in excess. 14. The ratio of the seed to the first electrode layer is
The piezoelectric element according to claim 1, wherein the content is 0.1 atom% to 15 atom%. 15. The ratio of the seed to the first electrode layer is
4. The ink jet head according to claim 3, which is 0.1 atom% to 15 atom%. 16. The piezoelectric element according to claim 1, wherein the adhesion layer has a thickness of 0.005 μm to 0.2 μm. 17. The ink jet head according to claim 3, wherein the adhesion layer has a thickness of 0.005 μm to 0.2 μm. 18. The orientation control layer has a thickness of 0.005 μm to 0.2.
2. The piezoelectric element according to claim 1, which has a thickness of μm. 19. The thickness of the orientation control layer is from 0.005 μm to 0.2.
The ink jet head according to claim 3, wherein the ink jet head has a thickness of μm. 20. The piezoelectric layer is formed by adding lead zirconate titanate or lead zirconate titanate with at least one member selected from the group consisting of magnesium (Mg), niobium (Nb) and zinc (Zn). 2. The piezoelectric element according to claim 1. 21. A piezoelectric layer comprising lead zirconate titanate or lead zirconate titanate to which at least one selected from the group consisting of magnesium (Mg), niobium (Nb) and zinc (Zn) is added. 4. The ink jet head according to claim 3. 22. The piezoelectric element according to claim 1, wherein the piezoelectric layer has a thickness of 1 μm to 10 μm. 23. The ink jet head according to claim 3, wherein the piezoelectric layer has a thickness of 1 μm to 10 μm.