JP2012006182A - Liquid jet head, liquid jet apparatus, piezoelectric element, and actuator apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid jet head which has a high insulation level to prevent leakage current from occurring, and also has less environmental load, and to provide a liquid jet apparatus.SOLUTION: The liquid jet head includes: a flow passage forming substrate 10 having a pressure generation chamber 12 communicated with a nozzle opening 21 that jets liquid; and a piezoelectric element 300 provided above the flow passage forming substrate 10, for causing pressure changes in the pressure generation chamber 12. The piezoelectric element 300 is provided with: a first electrode 60 which is preferentially oriented at a (100) surface, and has an orientation control layer 62 consisting mainly of a lantern nickel oxide having a perovskite structure; a piezoelectric layer 70 which is formed above the first electrode 60, consists of a composite oxide of iron, manganese, bismuth, titanium, and potassium, and is preferentially oriented at the (100) surface; and a second electrode 80 provided above the piezoelectric layer 70.

Description

  The present invention relates to a piezoelectric element in which a piezoelectric layer and electrodes are provided on both sides thereof, an actuator device having the piezoelectric element, a liquid ejecting head having the actuator device, and a liquid ejecting apparatus.

  As a piezoelectric element used in a liquid ejecting head, there is a piezoelectric material that exhibits an electromechanical conversion function, for example, a piezoelectric layer made of a crystallized dielectric material and sandwiched between two electrodes. Such a piezoelectric element is mounted on the liquid ejecting head as an actuator device in a flexural vibration mode, for example. As a typical example of a liquid ejecting head, for example, a part of a pressure generation chamber communicating with a nozzle opening for ejecting ink droplets is configured by a vibration plate, and the vibration plate is deformed by a piezoelectric element so that the ink in the pressure generation chamber is There is an ink jet recording head that pressurizes and ejects ink droplets from nozzle openings.

  A piezoelectric material used as a piezoelectric layer (piezoelectric ceramics) constituting such a piezoelectric element is required to have high piezoelectric characteristics, and a typical example is lead zirconate titanate (PZT) (Patent Document 1). reference).

However, from the viewpoint of environmental problems, there is a demand for a piezoelectric material with a reduced lead content. The piezoelectric material not containing lead, for example, chemical composition _{x [(Bi a K 1-} a) TiO 3] - (1-x) [BiFeO 3] ( where, 0.3 ≦ x ≦ 0.8, A piezoelectric ceramic represented by 0.4 <a <0.6) is disclosed (see Patent Document 2).

JP 2001-223404 A JP 2008-069051 A

  The piezoelectric ceramic described in Patent Document 2 is a so-called bulk material with a large film thickness. If this material is made into a thin film, insulation is low and leakage current is generated, so that it is difficult to use for piezoelectric elements. There is a problem.

  Such a problem exists not only in the ink jet recording head, but of course in other liquid ejecting heads that eject droplets other than ink as well. The same applies to piezoelectric actuators.

  In view of such circumstances, it is an object of the present invention to provide a liquid ejecting head, a liquid ejecting apparatus, a piezoelectric element, and an actuator device that have high insulating properties and can suppress generation of a leakage current and have a low environmental load. .

An aspect of the present invention that solves the above problems includes a flow path forming substrate having a pressure generating chamber communicating with a nozzle opening for ejecting liquid, and a pressure change in the pressure generating chamber provided above the flow path forming substrate. A first electrode having an orientation control layer mainly composed of a lanthanum nickel oxide having a perovskite structure and preferentially oriented in the (100) plane. A piezoelectric layer formed above the electrode and made of a complex oxide containing iron, manganese, bismuth, titanium, and potassium, preferentially oriented in the (100) plane, and a second electrode provided above the piezoelectric layer; A liquid ejecting head comprising:
In such an embodiment, by using a piezoelectric layer made of a composite oxide having a perovskite structure containing iron, manganese, bismuth, titanium, and potassium as the piezoelectric layer, it is possible to suppress the occurrence of leakage current with high insulation. Moreover, since the lead content can be suppressed, the burden on the environment can be reduced. Furthermore, by providing a piezoelectric layer on an orientation control layer made of lanthanum nickel oxide and preferentially oriented in the (100) plane, the piezoelectric layer can be preferentially oriented in the (100) plane and the (100) plane. By using a piezoelectric layer that is preferentially oriented, the durability and strain can be improved.

  Here, the orientation control layer preferably has a thickness of 10 nm or more. According to this, the piezoelectric layer preferentially oriented in the (100) plane can be easily formed on the orientation control layer.

  Further, the piezoelectric layer contains bismuth ferrate manganate and potassium bismuth titanate, and the bismuth ferrate manganate / bismuth potassium titanate which is the molar ratio of the bismuth ferrate manganate and the bismuth potassium titanate, It is preferable that it is 0.42 or more and 1.5 or less. According to this, generation | occurrence | production of leak current can be suppressed reliably.

  The piezoelectric layer is preferably a thin film having a thickness of 2 μm or less. According to this, a liquid ejecting head having a thin film piezoelectric layer can be provided.

  According to another aspect of the invention, there is provided a liquid ejecting apparatus including the liquid ejecting head according to the above aspect. In this aspect, the liquid ejecting head that has high insulation and can suppress the occurrence of leakage current is provided, so that the liquid ejecting apparatus is prevented from being broken down and having excellent reliability.

In another aspect of the present invention, a first electrode having an orientation control layer mainly composed of lanthanum nickel oxide having a perovskite structure and preferentially oriented in the (100) plane is formed above the first electrode. A piezoelectric layer made of a composite oxide containing iron, manganese, bismuth, titanium and potassium, and having a (100) plane preferentially oriented, and a second electrode provided above the piezoelectric layer. The piezoelectric element is characterized.
In such an embodiment, by using a piezoelectric layer made of a composite oxide having a perovskite structure containing iron, manganese, bismuth, titanium, and potassium as the piezoelectric layer, it is possible to suppress the occurrence of leakage current with high insulation. Moreover, since the lead content can be suppressed, the burden on the environment can be reduced. Furthermore, by providing a piezoelectric layer on an orientation control layer made of lanthanum nickel oxide and preferentially oriented in the (100) plane, the piezoelectric layer can be preferentially oriented in the (100) plane and the (100) plane. By using a piezoelectric layer that is preferentially oriented, the durability and strain can be improved.

Furthermore, another aspect of the present invention resides in an actuator device characterized in that the piezoelectric element of the above aspect is displaceably provided.
In this aspect, an actuator device with improved durability and amount of distortion due to repeated driving can be realized.

FIG. 2 is an exploded perspective view illustrating a schematic configuration of the recording head according to the first embodiment. FIG. 3 is a plan view of the recording head according to the first embodiment. FIG. 2 is a cross-sectional view of the recording head according to Embodiment 1 and an enlarged view thereof. 5 is a cross-sectional view illustrating a manufacturing process of the recording head according to Embodiment 1. FIG. 5 is a cross-sectional view illustrating a manufacturing process of the recording head according to Embodiment 1. FIG. 5 is a cross-sectional view illustrating a manufacturing process of the recording head according to Embodiment 1. FIG. 5 is a cross-sectional view illustrating a manufacturing process of the recording head according to Embodiment 1. FIG. 5 is a cross-sectional view illustrating a manufacturing process of the recording head according to Embodiment 1. FIG. It is a graph which shows the XRD measurement result of Examples 1, 2 and Comparative Example 1. It is a SEM image of Examples 3 and 4. It is a figure which shows JE Curve of Example 3 and 4. FIG. It is a figure which shows JE Curve of the samples 1, 3 and 5. It is a figure which shows the PE curve of the samples 1, 3, and 5. FIG. It is a coercive electric field-composition plot of samples 1-6. It is a dielectric constant-composition plot of samples 1-6. It is a figure which shows the SV curve of the samples 1-6. It is a piezoelectric constant-composition plot of samples 1-6. 7 is a ΔS / L ₁₂ −ΔV ₇₀ plot of Sample 7. It is a figure which shows the PE curve of the comparative sample 1. FIG. 1 is a diagram illustrating a schematic configuration of a recording apparatus according to an embodiment of the present invention.

(Embodiment 1)
FIG. 1 is an exploded perspective view showing a schematic configuration of an ink jet recording head which is an example of a liquid ejecting head according to Embodiment 1 of the invention, FIG. 2 is a plan view of FIG. 1, and FIG. FIG. 2 is a cross-sectional view taken along line AA ′ and an enlarged view of a main part thereof. As shown in FIGS. 1 to 3, the flow path forming substrate 10 of the present embodiment is made of a silicon single crystal substrate, and an elastic film 50 made of silicon dioxide is formed on one surface thereof.

  A plurality of pressure generating chambers 12 are arranged in parallel in the width direction of the flow path forming substrate 10. In addition, a communication portion 13 is formed in a region outside the longitudinal direction of the pressure generation chamber 12 of the flow path forming substrate 10, and the communication portion 13 and each pressure generation chamber 12 are provided for each pressure generation chamber 12. Communication is made via a supply path 14 and a communication path 15. The communication part 13 communicates with a manifold part 31 of a protective substrate, which will be described later, and constitutes a part of a manifold that becomes a common ink chamber for each pressure generating chamber 12. The ink supply path 14 is formed with a narrower width than the pressure generation chamber 12, and maintains a constant flow path resistance of ink flowing into the pressure generation chamber 12 from the communication portion 13. In this embodiment, the ink supply path 14 is formed by narrowing the width of the flow path from one side. However, the ink supply path may be formed by narrowing the width of the flow path from both sides. Further, the ink supply path may be formed by narrowing from the thickness direction instead of narrowing the width of the flow path. In the present embodiment, the flow path forming substrate 10 is provided with a liquid flow path including the pressure generation chamber 12, the communication portion 13, the ink supply path 14, and the communication path 15.

  Further, on the opening surface side of the flow path forming substrate 10, a nozzle plate 20 having a nozzle opening 21 communicating with the vicinity of the end of each pressure generating chamber 12 on the side opposite to the ink supply path 14 is provided with an adhesive. Or a heat-welded film or the like. The nozzle plate 20 is made of, for example, glass ceramics, a silicon single crystal substrate, stainless steel, or the like.

  On the other hand, an elastic film 50 made of silicon dioxide is formed on the side opposite to the opening surface of the flow path forming substrate 10, and an insulator film 55 made of zirconium oxide is formed on the elastic film 50. ing. On the insulator film 55, an adhesion layer 56 made of titanium oxide or the like and for improving the adhesion between the insulator film 55 and the first electrode 60 is provided.

  Further, on the adhesion layer 56, a first electrode 60, a piezoelectric layer 70 which is provided above the first electrode 60 and has a thickness of 2 μm or less, preferably 1 to 0.3 μm, and a piezoelectric layer The second electrode 80 provided above the 70 is laminated to form the piezoelectric element 300. Here, the term “above” includes not only directly above but also a state in which other members are interposed therebetween. Here, the piezoelectric element 300 refers to a portion including the first electrode 60, the piezoelectric layer 70, and the second electrode 80. In general, one electrode of the piezoelectric element 300 is used as a common electrode, and the other electrode and the piezoelectric layer 70 are patterned for each pressure generating chamber 12. In this case, a portion that is configured by any one of the patterned electrodes and the piezoelectric layer 70 and in which piezoelectric distortion is generated by applying a voltage to both electrodes is referred to as a piezoelectric active portion 320. In the present embodiment, the first electrode 60 is a common electrode of the piezoelectric element 300, and the second electrode 80 is an individual electrode of the piezoelectric element 300. However, there is no problem even if this is reversed for the convenience of the drive circuit and wiring. Here, the piezoelectric element 300 provided so as to be displaceable is referred to as an actuator device. In the above-described example, the elastic film 50, the insulator film 55, the adhesion layer 56, the first electrode 60, and the insulator film provided as necessary function as a diaphragm, but of course not limited thereto. For example, the elastic film 50 and the adhesion layer 56 may not be provided. Further, the piezoelectric element 300 itself may substantially serve as a diaphragm. Such a piezoelectric element 300 may be covered with a protective film made of an insulating material having moisture resistance of aluminum oxide.

  As shown in FIG. 3B, the first electrode 60 includes a conductive layer 61 made of platinum provided on the adhesion layer 56 and a perovskite made of lanthanum nickel oxide (LNO) provided on the conductive layer 61. An orientation control layer 62 having a structure.

  In the orientation control layer 62, the crystal orientation plane is preferentially oriented to the (100) plane in a pseudo cubic display. In the present invention, “crystals are preferentially oriented in the (100) plane” means that all crystals are oriented in the (100) plane and most crystals (for example, 90% or more) are ( 100) plane is preferentially oriented. As a result of performing an X-ray diffraction test, the orientation control layer of this embodiment has an orientation rate of (100) plane of 97% or more.

  Such an orientation control layer 62 is for preferentially orienting crystals of the piezoelectric layer 70 in the (100) plane when the piezoelectric layer 70 is formed on the orientation control layer 62 by epitaxial growth.

The piezoelectric layer 70 is made of a composite oxide having a perovskite structure including bismuth ferrate manganate (for example, Bi (Fe, Mn) O ₃ ) and bismuth potassium titanate (for example, (Bi, K) TiO ₃ ). In the A site of the perovskite structure, that is, the ABO ₃ type structure, oxygen is 12-coordinated, and the B site is 6-coordinated of oxygen to form an octahedron. Bi and K are located at the A site, and Fe, Mn, and Ti are located at the B site. In other words, the composite oxide having a perovskite structure containing bismuth ferrate manganate and potassium bismuth titanate can be said to be a solid solution in which bismuth ferrate manganate and bismuth potassium titanate are uniformly dissolved. The ratio of bismuth ferrate manganate (BFM) to potassium bismuth titanate (BKT) is such that BFM / BKT (molar ratio) is 0.42 or more and 1.5 or less, more preferably 0. .82 or more and 1.5 or less.

  As described above, when the piezoelectric material constituting the piezoelectric layer 70 is a complex oxide having a perovskite structure including bismuth ferrate manganate and potassium bismuth titanate, as shown in the examples described later, the insulation properties are as follows. This increases the leakage current.

  In addition, the piezoelectric layer 70 containing bismuth iron manganate and potassium bismuth titanate has a crystal orientation plane preferentially oriented in the (100) plane in a pseudo cubic display. In the present invention, “crystals are preferentially oriented in the (100) plane” means that all crystals are oriented in the (100) plane and most crystals (for example, 90% or more) are ( 100) plane is preferentially oriented. As a result of conducting an X-ray diffraction test, the (100) plane orientation rate of the piezoelectric layer 70 of this embodiment was 97% or more.

  Thus, by preferentially orienting the piezoelectric layer 70 in the (100) plane, the durability and piezoelectric characteristics (distortion amount) of the piezoelectric layer 70 can be improved. In addition, in lead zirconate titanate (PZT) that has been conventionally used as a piezoelectric layer, durability and strain can be improved by preferentially orienting crystals. Therefore, even if it is a complex oxide containing bismuth iron manganate and potassium bismuth titanate, which is a new piezoelectric material of the present invention, the durability and the amount of strain can be similarly improved.

  Such a piezoelectric layer 70 can have a relative dielectric constant at 25 ° C. of 300 or more, and more preferably 500 or more, as shown in examples described later. Therefore, the piezoelectric characteristics (distortion amount) are good.

  Each second electrode 80 that is an individual electrode of the piezoelectric element 300 is drawn from the vicinity of the end on the ink supply path 14 side and extended to the insulator film 55, for example, gold (Au). The lead electrode 90 which consists of etc. is connected.

  On the flow path forming substrate 10 on which such a piezoelectric element 300 is formed, that is, on the first electrode 60, the insulator film 55, and the lead electrode 90, a manifold portion 31 constituting at least a part of the manifold 100 is provided. The protective substrate 30 is bonded via an adhesive 35. In this embodiment, the manifold portion 31 penetrates the protective substrate 30 in the thickness direction and is formed across the width direction of the pressure generating chamber 12. As described above, the communication portion 13 of the flow path forming substrate 10. The manifold 100 is configured as a common ink chamber for the pressure generation chambers 12. Alternatively, the communication portion 13 of the flow path forming substrate 10 may be divided into a plurality of pressure generation chambers 12 and only the manifold portion 31 may be used as a manifold. Further, for example, only the pressure generation chamber 12 is provided in the flow path forming substrate 10, and the manifold 100 is attached to a member (for example, the elastic film 50, the insulator film 55, etc.) interposed between the flow path forming substrate 10 and the protective substrate 30. An ink supply path 14 that communicates with each pressure generating chamber 12 may be provided.

  A piezoelectric element holding portion 32 having a space that does not hinder the movement of the piezoelectric element 300 is provided in a region of the protective substrate 30 that faces the piezoelectric element 300. The piezoelectric element holding part 32 only needs to have a space that does not hinder the movement of the piezoelectric element 300, and the space may be sealed or unsealed.

  As such a protective substrate 30, it is preferable to use substantially the same material as the coefficient of thermal expansion of the flow path forming substrate 10, for example, glass, ceramic material, etc. In this embodiment, the same material as the flow path forming substrate 10 is used. The silicon single crystal substrate was used.

  The protective substrate 30 is provided with a through hole 33 that penetrates the protective substrate 30 in the thickness direction. The vicinity of the end portion of the lead electrode 90 drawn from each piezoelectric element 300 is provided so as to be exposed in the through hole 33.

  A drive circuit 120 for driving the piezoelectric elements 300 arranged in parallel is fixed on the protective substrate 30. For example, a circuit board or a semiconductor integrated circuit (IC) can be used as the drive circuit 120. The drive circuit 120 and the lead electrode 90 are electrically connected via a connection wiring 121 made of a conductive wire such as a bonding wire.

  In addition, a compliance substrate 40 including a sealing film 41 and a fixing plate 42 is bonded onto the protective substrate 30. Here, the sealing film 41 is made of a material having low rigidity and flexibility, and one surface of the manifold portion 31 is sealed by the sealing film 41. The fixing plate 42 is formed of a relatively hard material. Since the area of the fixing plate 42 facing the manifold 100 is an opening 43 that is completely removed in the thickness direction, one surface of the manifold 100 is sealed only with a flexible sealing film 41. Has been.

  In such an ink jet recording head I of this embodiment, ink is taken in from an ink introduction port connected to an external ink supply means (not shown), and the interior from the manifold 100 to the nozzle opening 21 is filled with ink, and then driven. In accordance with a recording signal from the circuit 120, a voltage is applied between each of the first electrode 60 and the second electrode 80 corresponding to the pressure generating chamber 12, and the elastic film 50, the insulator film 55, the adhesion layer 56, the first electrode By bending and deforming the electrode 60 and the piezoelectric layer 70, the pressure in each pressure generating chamber 12 is increased and ink droplets are ejected from the nozzle openings 21.

  Next, an example of a method for manufacturing the ink jet recording head of the present embodiment will be described with reference to FIGS. 4 to 8 are cross-sectional views in the longitudinal direction of the pressure generating chamber.

First, as shown in FIG. 4A, a silicon dioxide film 51 made of silicon dioxide (SiO ₂ ) or the like constituting the elastic film 50 is formed on the surface of a flow path forming substrate wafer 110, which is a silicon wafer, by thermal oxidation or the like. Form. Next, as shown in FIG. 4B, an insulator film 55 made of zirconium oxide is formed on the elastic film 50.

  Next, as shown in FIG. 5A, the adhesion layer 56 made of titanium oxide is formed on the insulator film 55, and the first electrode 60 is formed on the adhesion layer 56. Specifically, after an adhesion layer 56 made of titanium oxide or the like is formed on the insulator film 55, a conductive layer 61 made of platinum (Pt) and an orientation made of lanthanum nickel oxide (LNO) are formed on the adhesion layer 56. The first electrode 60 is formed by sequentially stacking the control layer 62. Note that the adhesion layer 56 and the conductive layer 61 can be formed by a sputtering method or an evaporation method. The orientation control layer 62 can be formed by a sputtering method.

  Next, the piezoelectric layer 70 is stacked on the first electrode 60. The method for manufacturing the piezoelectric layer 70 is not particularly limited. For example, a solution obtained by dissolving and dispersing an organometallic compound in a solvent is applied and dried, and further fired at a high temperature to obtain the piezoelectric layer 70 made of a metal oxide. The piezoelectric layer 70 can be formed using a chemical solution method such as a MOD (Metal-Organic Decomposition) method or a sol-gel method. The manufacturing method of the piezoelectric layer 70 is not limited to the MOD method or the sol-gel method. For example, the laser ablation method, the sputtering method, the pulse laser deposition method (PLD method), the CVD method, the aerosol deposition method. Etc.

  As a specific example of the formation procedure of the piezoelectric layer 70, first, as shown in FIG. 5B, an organometallic compound, specifically, Bi, Fe, Mn, Ti, A sol or MOD solution (precursor solution) containing an organometallic compound containing K at a ratio of the target composition ratio is applied by using a spin coating method or the like to form the piezoelectric precursor film 71 ( Application process).

  The precursor solution to be coated is prepared by mixing organometallic compounds containing Bi, Fe, Mn, Ti and K so that each metal has a desired molar ratio, and dissolving the mixture using an organic solvent such as alcohol. Or they are dispersed. As an organometallic compound containing Bi, Fe, Mn, Ti, and K, for example, a metal alkoxide, an organic acid salt, a β-diketone complex, and the like can be used. Examples of the organometallic compound containing Bi include bismuth 2-ethylhexanoate. Examples of the organometallic compound containing Fe include iron 2-ethylhexanoate. Examples of the organometallic compound containing Mn include manganese 2-ethylhexanoate. Examples of the organometallic compound containing Ti include titanium isopropoxide, titanium 2-ethylhexanoate, titanium (di-i-propoxide) bis (acetylacetonate), and the like. Examples of the organometallic compound containing K include potassium 2-ethylhexanoate, potassium acetate, potassium acetylacetonate, and the like.

Next, the piezoelectric precursor film 71 is heated to a predetermined temperature (for example, 100 to 200 ° C.) and dried for a predetermined time (drying process). Next, the dried piezoelectric precursor film 71 is degreased by heating it to a predetermined temperature (for example, 350 to 450 ° C.) and holding it for a certain time (degreasing step). The degreasing referred to here is to release the organic component contained in the piezoelectric precursor film 71 as, for example, NO ₂ , CO ₂ , H ₂ O or the like. The atmosphere in the drying process or the degreasing process is not limited, and it may be in the air or in an inert gas.

  Next, as shown in FIG. 5C, the piezoelectric precursor film 71 is crystallized by heating to a predetermined temperature, for example, about 600 to 800 ° C., and holding it for a certain period of time, thereby forming the piezoelectric film 72. (Baking process). Also in this firing step, the atmosphere is not limited, and may be in the air or in an inert gas.

  Examples of the heating apparatus used in the drying process, the degreasing process, and the baking process include an RTA (Rapid Thermal Annealing) apparatus and a hot plate that are heated by irradiation with an infrared lamp.

  Thus, since the piezoelectric film 72 formed on the first electrode 60 is formed by epitaxial growth on the orientation control layer 62 preferentially oriented on the (100) plane, the same (100) plane as the orientation control layer 62 is formed. Is preferentially oriented.

  Next, as shown in FIG. 6A, for example, the first electrode 60 and the first layer of the piezoelectric film 72 are inclined on the piezoelectric film 72 using a resist (not shown) having a predetermined shape as a mask. Pattern simultaneously.

  Next, after peeling off the resist, the above-described coating process, drying process, degreasing process, coating process, drying process, degreasing process, and baking process are repeated a plurality of times according to the desired film thickness, etc. By forming the piezoelectric layer 70 made of the material, a piezoelectric layer 70 having a predetermined thickness composed of a plurality of layers of piezoelectric films 72 is formed as shown in FIG. 6B. For example, when the film thickness of the coating solution per one time is about 0.1 μm, for example, the entire film thickness of the piezoelectric layer 70 composed of the ten piezoelectric films 72 is about 1.1 μm. In the present embodiment, the piezoelectric film 72 is provided by being laminated, but only one layer may be provided.

  After the piezoelectric layer 70 is formed in this way, as shown in FIG. 7A, a second electrode 80 made of platinum or the like is formed on the piezoelectric layer 70 by sputtering or the like, and each pressure generating chamber 12 is formed. Then, the piezoelectric layer 70 and the second electrode 80 are simultaneously patterned in a region opposite to each other to form the piezoelectric element 300 including the first electrode 60, the piezoelectric layer 70, and the second electrode 80. The patterning of the piezoelectric layer 70 and the second electrode 80 can be performed collectively by dry etching via a resist (not shown) formed in a predetermined shape. Thereafter, post-annealing may be performed in a temperature range of 600 ° C. to 800 ° C. as necessary. Thereby, a good interface between the piezoelectric layer 70 and the first electrode 60 or the second electrode 80 can be formed, and the crystallinity of the piezoelectric layer 70 can be improved.

  Next, as shown in FIG. 7B, a lead electrode 90 made of, for example, gold (Au) or the like is formed over the entire surface of the flow path forming substrate wafer 110, and then a mask pattern made of, for example, a resist or the like. Patterning is performed for each piezoelectric element 300 via (not shown).

  Next, as shown in FIG. 7C, a protective substrate wafer 130 that is a silicon wafer and serves as a plurality of protective substrates 30 is placed on the piezoelectric element 300 side of the flow path forming substrate wafer 110 via an adhesive 35. After the bonding, the flow path forming substrate wafer 110 is thinned to a predetermined thickness.

  Next, as shown in FIG. 8A, a mask film 52 is newly formed on the flow path forming substrate wafer 110 and patterned into a predetermined shape.

  Then, as shown in FIG. 8B, the flow path forming substrate wafer 110 is anisotropically etched (wet etching) using an alkaline solution such as KOH through the mask film 52 to form the piezoelectric element 300. Corresponding pressure generating chambers 12, communication portions 13, ink supply passages 14, communication passages 15 and the like are formed.

  Thereafter, unnecessary portions of the outer peripheral edge portions of the flow path forming substrate wafer 110 and the protective substrate wafer 130 are removed by cutting, for example, by dicing. Then, after removing the mask film 52 on the surface opposite to the protective substrate wafer 130 of the flow path forming substrate wafer 110, the nozzle plate 20 having the nozzle openings 21 formed therein is bonded, and the protective substrate wafer 130 is also formed. The compliance substrate 40 is bonded to the substrate, and the flow path forming substrate wafer 110 or the like is divided into a single chip size flow path forming substrate 10 or the like as shown in FIG. To do.

  Hereinafter, the present invention will be described more specifically with reference to examples. In addition, this invention is not limited to a following example.

(Example 1)
An elastic film made of silicon dioxide having a thickness of 1070 nm was formed on the surface of the silicon substrate oriented in (100) by thermal oxidation. Next, an insulator film made of zirconium oxide having a thickness of 400 nm was formed on the elastic film. Next, a titanium film having a thickness of 40 nm was formed on the insulator film by RF sputtering, and an adhesion layer made of titanium oxide was formed by thermal oxidation.

  Next, a conductive layer made of platinum having a thickness of 130 nm was formed on the adhesion layer by DC sputtering. Next, an orientation control layer made of lanthanum nickel oxide having a thickness of 10 nm was formed on the conductive layer to obtain the first electrode.

  A piezoelectric layer was formed on the first electrode. The method is as follows. First, Bi, K, Fe, Mn, Ti xylene, octane and butanol solutions were mixed at a predetermined ratio to prepare a precursor solution.

  The precursor solution was dropped onto the substrate on which the first electrode was formed, and the substrate was rotated at 3000 rpm to form a piezoelectric precursor film (application process). Next, drying and degreasing were performed at 150 ° C. for 2 minutes and at 350 ° C. for 4 minutes (drying and degreasing process). After repeating this application | coating process, drying, and a degreasing process 3 times, it baked at 700 degreeC for 5 minute (s) by Rapid Thermal Annealing (RTA) (baking process). This coating process, drying and degreasing process was repeated 3 times, and then the process of performing a baking process in which baking was performed in a lump was repeated 3 times, and a total of 900 nm thick piezoelectric layers were formed by a total of 9 applications.

After that, a platinum film having a film thickness of 100 nm is formed as a second electrode by a DC sputtering method on the piezoelectric layer, and then fired at 650 ° C. for 5 minutes using RTA, whereby Bi (Fe _0.97 , Mn _0.03 ) O ₃ and (Bi _0.5 , K _0.5 ) TiO ₃ composite oxide having a perovskite structure, which is bismuth iron manganate / potassium bismuth titanate, ie Bi (Fe _0.97 , Mn _0.03 ) O ₃ / (Bi _0.5 , K _0.5 ) TiO ₃ having a molar ratio of 1.50 was formed as a piezoelectric element. In addition, as above-mentioned, the molar ratio of BF-BKT and BM is BF-BKT: BM = 100: 3.

(Example 2)
A piezoelectric element of Example 2 was formed by the same material and manufacturing method as Example 1 described above except that the first electrode having an orientation control layer made of lanthanum nickel oxide having a thickness of 50 nm was formed.

(Comparative Example 1)
For comparison, the first electrode without the lanthanum nickel oxide was used. That is, the piezoelectric element of Comparative Example 1 was formed by the same material and manufacturing method as Example 1 described above, except that an adhesion layer made of titanium oxide and a conductive layer made of platinum were provided as the first electrode.

(Test Example 1)
For the piezoelectric elements of Examples 1 and 2 and Comparative Example 1, a piezoelectric layer was used at room temperature by X-ray diffraction wide angle method (XRD) using “D8 DISCOVER” manufactured by Bruker AKS and using CuKα rays as an X-ray source. The X-ray diffraction chart was obtained. The result is shown in FIG.

  As shown in FIG. 9, in the piezoelectric layers of Examples 1 and 2, the diffraction intensity peaks (2θ) derived from the (100) plane and the (200) plane were detected, and other orientations, for example, (110) The peak of diffraction intensity on the surface was hardly detected. In contrast, in the piezoelectric layer of Comparative Example 1, diffraction intensity peaks derived from the (100) plane, (200) plane, and (110) plane were detected. From this result, an alignment control layer made of lanthanum nickel oxide of 10 nm or more is provided as in Examples 1 and 2, and the piezoelectric layer formed on this alignment control layer can be preferentially aligned on the (100) plane. Even if the orientation control layer is thicker than 50 nm, the piezoelectric layer on the orientation control layer can be preferentially oriented in the (100) plane. However, if the orientation control layer is too thick, the thickness of the entire first electrode is increased. The first electrode may be a factor that hinders the displacement of the piezoelectric element, and if the conductive layer is thinned to keep the thickness of the first electrode the same, problems such as a decrease in conductivity occur. There is a risk of doing. Therefore, the thickness of the orientation control layer is preferably 50 nm or less. Incidentally, in Examples 1 and 2, a peak of diffraction intensity of the (200) plane is detected, but the (200) plane is equivalent to the (100) plane.

In addition, by providing the orientation control layer, the orientation of the piezoelectric layer can be controlled, as described above, with bismuth ferrate manganate (for example, Bi (Fe, Mn) O ₃ ) as the piezoelectric layer. This is because a material containing bismuth potassium titanate (for example, (Bi, K) TiO ₃ ) is used. That is, when a material containing bismuth iron manganate (for example, Bi (Fe, Mn) O ₃ ) and bismuth titanate (for example, BiTiO ₃ ) is used as the piezoelectric layer, the orientation control is made of lanthanum nickel oxide. Even if the layer is provided as a base, the piezoelectric layer formed on the orientation control layer is not preferentially oriented.

In Examples 1 and 2 described above, a piezoelectric layer in which Bi (Fe _0.97 , Mn _0.03 ) O ₃ / (Bi _0.5 , K _0.5 ) TiO ₃ is 1.50 in molar ratio. In the same manner, even when the piezoelectric layer has a molar ratio other than this, it can be preferentially oriented in the (100) plane by being formed on the orientation control layer made of preferentially oriented lanthanum nickel oxide. .

(Example 3)
Using the same material as in Example 1 described above, the piezoelectric element of Example 3 was formed by the following procedure.

  As a method of forming the piezoelectric element of Example 3, an elastic film, an insulator film, an adhesion layer, a first electrode having a conductive layer and an orientation control layer were sequentially stacked on a silicon substrate.

  Next, a step of performing a firing step of firing all at once after repeating the coating step, drying and degreasing step three times on the first electrode is repeated three times, and the total thickness of the piezoelectric body is 900 nm by applying nine times. A layer was formed. At this time, after each firing step, a washing step of washing the surface of the fired piezoelectric layer with pure water was performed. That is, the cleaning process is performed between the baking process and the next coating process. Note that the cleaning step may be performed after the final baking step, or the cleaning step may not be performed. In this embodiment, the cleaning process is not performed after the final baking process.

Example 4
The piezoelectric element of Example 4 was formed by the same manufacturing process except that the cleaning process was not performed using the same material as that of Example 3 described above.

(Test Example 2)
The piezoelectric elements of Examples 3 and 4 were observed with a scanning electron microscope (SEM). The result is shown in FIG. FIG. 10A is an SEM of Example 3, and FIG. 10B is an SEM image of Example 4.

  As shown in FIG. 10 (b), the altered layer 501 is formed in the piezoelectric layer of Example 4 formed without performing the cleaning step for each firing step, whereas FIG. 10 (a) shows. As described above, it was confirmed that the deteriorated layer 500 formed in each firing process could be suppressed in the piezoelectric layer of Example 3 that had undergone the cleaning process.

  For the piezoelectric elements of Examples 3 and 4, J-E Curve was measured at room temperature (25 ° C.) using “4140B” manufactured by Hewlett-Packard Company. The measurement used an electrode pattern with φ = 300 μm. The result is shown in FIG. As shown in FIG. 11, in the piezoelectric layer of Example 4 formed without performing the cleaning process, the leakage current (current density) increases rapidly as the applied voltage increases (or decreases), and the applied voltage It was confirmed that dielectric breakdown occurred at a temperature exceeding −20V. In contrast, the piezoelectric layer of Example 3 formed by performing the cleaning process has a lower rate of increase in current density with respect to the applied voltage than that of Example 4, and dielectric breakdown until the applied voltage reaches close to −40V. Was not confirmed. Therefore, the piezoelectric element of Example 3 has a reduced leakage current and improved withstand voltage compared to the piezoelectric element of Example 4.

Here, other examples of the piezoelectric layer will be described below.
(Sample 1)
An elastic film made of silicon dioxide having a thickness of 1070 nm was formed on the surface of the silicon substrate oriented in (100) by thermal oxidation. Next, a titanium film having a film thickness of 40 nm was formed on the elastic film by RF sputtering, and an adhesion layer made of titanium oxide was formed by thermal oxidation. Next, a conductive layer made of platinum having a film thickness of 130 nm was formed on the adhesion layer by DC sputtering to form a first electrode oriented in (111).

  Next, a piezoelectric layer was formed on the first electrode by spin coating. The method is as follows. First, Bi, K, Fe, Mn, Ti xylene, octane and butanol solutions were mixed at a predetermined ratio to prepare a precursor solution. And this precursor solution was dripped on the said board | substrate with which the titanium oxide film and the 1st electrode were formed, the board | substrate was rotated at 3000 rpm, and the piezoelectric precursor film | membrane was formed (application | coating process). Next, drying and degreasing were performed at 150 ° C. for 2 minutes and at 400 ° C. for 4 minutes (drying and degreasing process). After repeating this application | coating process, drying, and a degreasing process 3 times, it baked at 650 degreeC for 5 minutes by Rapid Thermal Annealing (RTA) (baking process). This coating process, drying and degreasing process was repeated 3 times, and then the process of performing a baking process in which baking was performed in a lump was repeated 3 times, and a total of 900 nm thick piezoelectric layers were formed by a total of 9 applications.

After that, a platinum film having a film thickness of 100 nm is formed as a second electrode by a DC sputtering method on the piezoelectric layer, and then fired at 650 ° C. for 5 minutes using RTA, whereby Bi (Fe _0.97 , Mn _0.03 ) O ₃ and (Bi _0.5 , K _0.5 ) TiO ₃ composite oxide having a perovskite structure, which is bismuth iron manganate / potassium bismuth titanate, ie Bi (Fe _0.97 , Mn _0.03 ) O ₃ / (Bi _0.5 , K _0.5 ) TiO ₃ having a molar ratio of 1.50 was formed as a piezoelectric element.

(Samples 2-6)
The mixing ratio of Bi, K, Fe, Mn and Ti in xylene, octane and butanol solutions was changed, and bismuth ferrate manganate and titanate of bismuth ferrate manganate / potassium titanate (molar ratio) shown in Table 1 A piezoelectric element 300 was formed in the same manner as in Sample 1 except that the composite oxide having a perovskite structure containing bismuth potassium was used as the piezoelectric layer 70.

(Sample 7)
First, a silicon dioxide film having a thickness of 1070 nm was formed on the surface of a silicon substrate oriented in (100) by thermal oxidation. Next, a zirconium film was formed on the silicon dioxide film by sputtering, and thermally oxidized to form a 400 nm zirconium oxide film. Next, a titanium film with a thickness of 40 nm was formed on the zirconium oxide film by RF sputtering, and the titanium oxide film was formed by thermal oxidation. Next, a platinum film having a thickness of 130 nm oriented in (111) was formed on the titanium oxide film by DC sputtering. Next, a photoresist having a predetermined shape was formed on the platinum film, and patterning was performed by dry etching to form a first electrode.

  Next, a piezoelectric layer was formed on the first electrode by spin coating. The method is as follows. First, Bi, K, Fe, Mn, Ti xylene, octane and butanol solutions were mixed at a predetermined ratio to prepare a precursor solution. And this precursor solution was dripped on the said board | substrate with which the titanium oxide film and the 1st electrode were formed, the board | substrate was rotated at 3000 rpm, and the piezoelectric precursor film | membrane was formed (application | coating process). Next, drying and degreasing were performed at 150 ° C. for 2 minutes and at 400 ° C. for 4 minutes (drying and degreasing process). After repeating this application | coating process, drying, and a degreasing process 3 times, it baked at 750 degreeC for 5 minute (s) by Rapid Thermal Annealing (RTA) (baking process). This coating process, drying and degreasing process was repeated 3 times, and then the process of performing a baking process in which baking was performed in a lump was repeated 3 times, and a total of 900 nm thick piezoelectric layers were formed by a total of 9 applications.

  Thereafter, a platinum film having a thickness of 100 nm was formed on the piezoelectric layer by DC sputtering. Next, heat treatment was performed by RTA at 750 ° C. for 5 minutes. Next, a photoresist having a predetermined shape was formed on the platinum film, and platinum and the piezoelectric layer were patterned by dry etching. Thereafter, an aluminum oxide film was produced by sputtering. Next, a photoresist having a predetermined shape was formed and patterned twice by dry etching to process the aluminum oxide film into a predetermined shape.

Then, after protecting the upper part of this processed material with an organic film, the lower part was processed to a predetermined thickness with a grinder, and then the ground surface was polished. Next, an alkali resistant hard mask was formed and patterned into a predetermined shape. Next, silicon was processed into a predetermined shape by wet etching. Thereafter, the organic film was peeled off to produce a piezoelectric actuator having a piezoelectric element and a pressure generating chamber. The piezoelectric layer is a complex oxide having a perovskite structure containing Bi (Fe _0.97 , Mn _0.03 ) O ₃ and (Bi _0.5 , K _0.5 ) TiO ₃ , Bismuth manganate / potassium bismuth titanate, that is, Bi (Fe _0.97 , Mn _0.03 ) O ₃ / (Bi _0.5 , K _0.5 ) TiO ₃ has a molar ratio of 1.22.

(Comparative sample 1)
Ceramics were prepared by a solid phase method using bismuth oxide, iron oxide, potassium carbonate, and titanium oxide solid powders as raw materials. This method is as follows. First, the above-mentioned raw materials are mixed so that the molar ratio is Bi: Fe: K: Ti = 70: 40: 30: 60, and then the above-mentioned mixed powder and an equivalent amount of ethanol and four times the amount of zirconia of the raw materials. Balls were added and mixed and ground for 24 hours. Then, after removing the zirconia balls, drying was performed to obtain a mixed powder. This mixed powder was heated to 700 ° C. with an electric furnace to obtain a temporarily fired powder. After adding 2.5% by weight of polyvinyl alcohol (PVA) as a binder to the calcined powder and mixing, pellets having a diameter of 1 mm were produced by press molding. The pellet was covered with pre-fired powder, subjected to binder removal treatment at 700 ° C., and then fired at 1060 ° C. to obtain ceramic pellets. After this pellet was polished, a silver electrode was applied by screen printing and baked at 700 ° C. to obtain a ceramic provided with the electrode.

(Test Example 2)
For the piezoelectric elements of Samples 1 to 6, the powder X-ray diffraction pattern of the piezoelectric layer was obtained at room temperature (25 ° C.) using “D8 Discover” manufactured by Bruker AXS, using CuKα rays as the X-ray source. . As a result, in all the samples 1 to 6, only the peak derived from the ABO ₃ type structure and the peak derived from the substrate were observed, and no heterogeneous phase was observed.

(Test Example 3)
For each of the piezoelectric elements of Samples 1 to 6, J-E Curve was measured at room temperature (25 ° C.) using “4140B” manufactured by Hewlett-Packard Company. The measurement used an electrode pattern with φ = 300 μm. As a result, in all the examples, it can be seen that the current density is small and the leakage is suppressed. As an example of the results, the results of Sample 1, Sample 3, and Sample 5 are shown in FIG.

(Test Example 4)
Regarding the piezoelectric elements of Samples 1 to 6, “FCE-1A” manufactured by Toyo Technica Co., Ltd., using an electrode pattern of φ = 400 μm, and the relationship between the amount of polarization and the electric field (PE curve) at a frequency of 1 kHz at room temperature. Asked. As a result, all samples showed good hysteresis derived from ferroelectricity. As an example of the results, sample 1 is shown in FIG. 13 (a), sample 3 is shown in FIG. 13 (b), and sample 5 is shown in FIG. 13 (c).

For the piezoelectric elements of Samples 1 to 6, the coercive electric field E _C was obtained from the relationship between the polarization amount and the electric field (P-E curve) in Test Example 4. The diagram plots the coercive field E _C with respect to bismuth ferrate manganate / bismuth potassium titanate (molar ratio), shown in Figure 14. As shown in FIG. 14, since the coercive electric field E _C is less than 164 kVcm ^{−1 in} all the samples 1 to 6, the ink jet recording head can be driven by applying a voltage with an electric field of 164 kVcm ⁻¹ or more. It can be said. For example, since the coercive electric field E _C is less than 200 kVcm ⁻¹ , it can be seen that a thin film having a thickness of 1 μm can be polarized with a voltage (intermediate potential) of 20 V and can drive an ink jet recording head. Also, since the sample 3 and sample 4 is _{E C} has become less than 100KVcm ^-1, even in a thin film of 2μm thick in this composition vicinity is found to be polarizable in an intermediate potential of 20V. The coercive electric field of the sample is larger than that of the comparative sample 1 described later. This is a phenomenon unique to a thin film in which the coercive electric field is increased in the thin film due to factors such as the interface, stress, and crystallinity.

(Test Example 5)
For each of the piezoelectric elements of samples 1 to 6, the relative dielectric constant of the piezoelectric layer was measured at a frequency of 1 kHz at room temperature (25 ° C.) using an electrode pattern of φ = 500 μm using “4294A” manufactured by Hewlett-Packard. did. FIG. 15 shows a plot of relative dielectric constant ε _r against bismuth iron manganate / potassium bismuth titanate (molar ratio). As a result, as shown in FIG. 15, the relative dielectric constant was as high as 300 or more, and in samples 1 to 4, it was 500 or more. The relative dielectric constant has a maximum with respect to the composition ratio. When BFM / BKT = 1.11 (sample 2), ε _r = 616, and when BFM / BKT = 1.00 (sample 3), ε _r = It showed a high value of 628. These have a dielectric constant more than three times that of bismuth ferrate (BFO).

(Test Example 6)
For the piezoelectric elements of Samples 1 to 6, an electric field induced strain was applied by applying a voltage of 1 kHz using an electrode pattern of φ = 500 μm at room temperature (25 ° C.) using a displacement measuring device (DBLI) manufactured by Axact. -The voltage relationship was determined. 16 (a), Sample 2 in FIG. 16 (b), Sample 3 in FIG. 16 (c), Sample 4 in FIG. 16 (d), Sample 5 in FIG. 16 (e), Sample 6 is shown in FIG. As a result, as shown in FIG. 16, all the samples were favorably displaced.

From the measurement results shown in FIG. 16, the piezoelectric constant d ₃₃ was determined by dividing the maximum piezoelectric strain S _max by the maximum applied electric field E _max (S _max / E _max ). The diagram plots the d ₃₃ with respect to bismuth ferrate manganate / bismuth potassium titanate (molar ratio), shown in Figure 17. From FIG. 17, d ₃₃ has a maximum with respect to the composition. When BFM / BKT = 1.11 (sample 2), d ₃₃ = 55 pmV ⁻¹ , and when BFM / BKT = 1.00 (sample 3), d ₃₃ A tendency similar to ₃₃ = 40 pmV ⁻¹ and the maximum dielectric constant of Test Example 5 was exhibited. From this, it can be seen that an increase in dielectric constant corresponds to an improvement in piezoelectricity.

(Test Example 7)
The elastic film 50, the insulator film 55, the adhesion layer 56, the first electrode 60, the piezoelectric layer 70, the second electrode 80, and the protective film (which are generated when the potential difference ΔV ₇₀ is applied to the piezoelectric layer 70 of the sample 7) The maximum change width ΔS of the relative position of the (aluminum oxide film) was measured at room temperature (25 ° C.) using a laser Doppler displacement meter. FIG. 18 shows the measurement results when the applied voltage is changed. The vertical axis is a value (ΔS / L ₁₂ ) obtained by dividing ΔS by the length L ₁₂ in the longitudinal direction of the pressure generating chamber 12, which is per unit length of the pressure generating chamber 12 generated when a voltage is applied. Means the amount of deformation. That is, it corresponds to the liquid ejection capability of the head. Moreover, since it is a dimensionless number, U is used formally as a unit system.

From FIG. 18, it was found that Sample 7 has good actuator characteristics of about 100 μU at ΔV ₇₀ = 20V and about 200 μU at 40V. In addition, in the region of ΔV ₇₀ = 20 to 50 V, a good linear response was exhibited with respect to the applied voltage, and it was found that ejection droplet diameter control (MSDT) by the applied voltage waveform was easy.

(Test Example 8)
The ceramic of Comparative Sample 1 was measured using “FCE-1A” manufactured by Toyo Technica Co., Ltd. in silicon oil at room temperature at 10 kHz, and the relationship between the amount of polarization and the electric field (PE curve) was determined. The results are shown in FIG. As shown in FIG. 19, good hysteresis derived from ferroelectricity was observed. The coercive electric field E _C was 14 kVcm ⁻¹ .

Further, the ceramic of Comparative Sample 1 was subjected to polarization treatment by applying a DC electric field of 50 kVcm ⁻¹ for 3 minutes in silicon oil at room temperature. In addition, the electric field used for the polarization process is a sufficient electric field for the polarization process from the PE curve in FIG.

The piezoelectric characteristics of the ceramic of Comparative Sample 1 subjected to the polarization treatment were evaluated by the piezoelectric constant (d ₃₃ ) in the polarization direction using “Piezo d ₃₃ Meter” manufactured by Chinese Academy of Sciences. The measurement was performed at room temperature. The “Piezo d ₃₃ Meter” manufactured by the Chinese Academy of Sciences measures the piezoelectric constant by measuring the amount of polarization induced by pressure. As a result, the piezoelectric constant of Comparative Sample 1 was d ₃₃ = 36 pCN ⁻¹ . This is a value of about 1/5 of the piezoelectric constant obtained from the strain induced by voltage application in Patent Document 2, indicating that the ceramic of Comparative Sample 1 cannot maintain polarization by a general polarization process. Yes. Therefore, it turned out that it is difficult to use for an ink jet recording head.

(Other embodiments)
As mentioned above, although one Embodiment of this invention was described, the basic composition of this invention is not limited to what was mentioned above. For example, in the above-described embodiment, the silicon single crystal substrate is exemplified as the flow path forming substrate 10, but the present invention is not particularly limited thereto, and for example, a material such as an SOI substrate or glass may be used.

  For example, in the above-described embodiment, the piezoelectric element 300 includes the first electrode 60, the piezoelectric layer 70, and the second electrode 80 on the flow path forming substrate 10 via the elastic film 50 and the insulator film 55. However, the present invention is not particularly limited thereto, and for example, an intermediate electrode may be provided in the middle of the thickness of the piezoelectric layer between the lower electrode and the upper electrode. In such a configuration, an orientation control layer may be provided at the interface with the piezoelectric layer of the lower electrode, and an orientation control layer may be provided at the interface with the piezoelectric layer on the upper electrode side of the intermediate electrode. In both cases, an orientation control layer may be provided. Incidentally, when the orientation control layer is provided at the interface between the lower electrode and the piezoelectric layer, the lower electrode corresponds to the first electrode described in the claims, and the intermediate electrode corresponds to the first electrode described in the claims. It corresponds to two electrodes. Further, when the orientation control layer is provided at the interface with the piezoelectric layer on the upper electrode side of the intermediate electrode, the intermediate electrode corresponds to the first electrode recited in the claims, and the upper electrode is claimed. It corresponds to the second electrode described in the range.

  Furthermore, the ink jet recording heads of these embodiments constitute a part of a recording head unit including an ink flow path communicating with an ink cartridge and the like, and are mounted on the ink jet recording apparatus. FIG. 20 is a schematic view showing an example of the ink jet recording apparatus.

  In the ink jet recording apparatus II shown in FIG. 20, the recording head units 1A and 1B having the ink jet recording head I are detachably provided with cartridges 2A and 2B constituting ink supply means, and the recording head units 1A and 1B. Is mounted on a carriage shaft 5 attached to the apparatus main body 4 so as to be movable in the axial direction. The recording head units 1A and 1B, for example, are configured to eject a black ink composition and a color ink composition, respectively.

  The driving force of the driving motor 6 is transmitted to the carriage 3 via a plurality of gears and timing belt 7 (not shown), so that the carriage 3 on which the recording head units 1A and 1B are mounted is moved along the carriage shaft 5. The On the other hand, the apparatus body 4 is provided with a platen 8 along the carriage shaft 5, and a recording sheet S that is a recording medium such as paper fed by a paper feed roller (not shown) is wound around the platen 8. It is designed to be transported.

  In the above-described embodiment, the ink jet recording head has been described as an example of the liquid ejecting head. However, the present invention is widely applied to all liquid ejecting heads, and the liquid ejecting ejects a liquid other than ink. Of course, it can also be applied to the head. Other liquid ejecting heads include, for example, various recording heads used in image recording apparatuses such as printers, color material ejecting heads used in the manufacture of color filters such as liquid crystal displays, organic EL displays, and FEDs (field emission displays). Examples thereof include an electrode material ejection head used for electrode formation, a bioorganic matter ejection head used for biochip production, and the like.

  The present invention is not limited to a piezoelectric element mounted on a liquid jet head typified by an ink jet recording head, but may be an ultrasonic device such as an ultrasonic transmitter, an ultrasonic motor, a pressure sensor, a pyroelectric sensor, or the like. The present invention can also be applied to a piezoelectric element mounted on the apparatus. The present invention can be similarly applied to a ferroelectric element such as a ferroelectric memory.

  I ink jet recording head (liquid ejecting head), II ink jet recording apparatus (liquid ejecting apparatus), 10 flow path forming substrate, 12 pressure generating chamber, 13 communicating portion, 14 ink supply path, 20 nozzle plate, 21 nozzle opening, 30 protective substrate, 31 manifold portion, 32 piezoelectric element holding portion, 40 compliance substrate, 50 elastic film, 55 insulator film, 56 adhesion layer, 60 first electrode, 61 conductive layer, 62 orientation control layer, 70 piezoelectric layer, 80 Second electrode, 90 Lead electrode, 100 Manifold, 120 Drive circuit, 300 Piezoelectric element

Claims (7)

A flow path forming substrate having a pressure generating chamber communicating with a nozzle opening for ejecting liquid, and a piezoelectric element provided above the flow path forming substrate and causing a pressure change in the pressure generating chamber,
The piezoelectric element has a first electrode having an orientation control layer mainly composed of lanthanum nickel oxide having a perovskite structure preferentially oriented in the (100) plane;
A piezoelectric layer formed above the first electrode, made of a composite oxide containing iron, manganese, bismuth, titanium and potassium, and preferentially oriented in the (100) plane;
A liquid ejecting head comprising: a second electrode provided above the piezoelectric layer.   The liquid ejecting head according to claim 1, wherein the orientation control layer has a thickness of 10 nm or more.   The piezoelectric layer contains bismuth ferrate manganate and potassium bismuth titanate, and the molar ratio of the bismuth ferrate manganate to the bismuth potassium titanate is bismuth ferrate manganate / bismuth potassium titanate is 0.00. The liquid ejecting head according to claim 1, wherein the liquid ejecting head is 42 or more and 1.5 or less.   The liquid ejecting head according to claim 1, wherein the piezoelectric layer is a thin film having a thickness of 2 μm or less.   A liquid ejecting apparatus comprising the liquid ejecting head according to claim 1. A first electrode having an orientation control layer predominately oriented in the (100) plane and comprising a lanthanum nickel oxide having a perovskite structure as a main component;
A piezoelectric layer formed above the first electrode, made of a composite oxide containing iron, manganese, bismuth, titanium and potassium, and preferentially oriented in the (100) plane;
A piezoelectric element comprising: a second electrode provided above the piezoelectric layer.   An actuator device comprising the piezoelectric element according to claim 6 so as to be displaceable.