JP2012018994A - Manufacturing method of liquid injection head, liquid injection device, manufacturing method of piezoelectric element, and manufacturing method of composition for piezoelectric material film formation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a liquid injection head which is small in environmental load and has a piezoelectric material layer with preferred (100) face orientation.SOLUTION: A manufacturing method of a liquid injection head, which includes: a pressure generation chamber communicating with a nozzle opening to inject liquid; and a piezoelectric element causing pressure change in the pressure generation chamber, includes the steps of: forming a platinum film consisting of platinum in preferred (111) face orientation; and forming a piezoelectric material precursor film by using a composition for piezoelectric material film formation obtained by mixing a xylene solution of an organometallic compound containing Bi, La, Fe and Mn and containing at least La and a xylene solution of an organometallic compound containing Fe, on the platinum film. The method further includes the steps of: forming a piezoelectric material layer by calcining the piezoelectric material precursor film; and forming an electrode on the piezoelectric material layer.

Description

  The present invention relates to a manufacturing method of a liquid ejecting head having a piezoelectric element provided with a piezoelectric layer and an electrode, a liquid ejecting apparatus, a manufacturing method of a piezoelectric element, and a manufacturing method of a composition for forming a piezoelectric film.

  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 ink in the pressure generation chamber is discharged. There is an ink jet recording head that pressurizes and ejects ink droplets from nozzle openings. In the piezoelectric element mounted on such an ink jet recording head, for example, a uniform piezoelectric material layer is formed over the entire surface of the diaphragm by a film forming technique, and this piezoelectric material layer is formed into a pressure generating chamber by a lithography method. There is one in which piezoelectric elements are formed so as to be separated into corresponding shapes and independent for each pressure generating chamber.

  As a piezoelectric material used for such a piezoelectric element, lead zirconate titanate (PZT) is cited (see Patent Document 1).

JP 2001-223404 A

However, since the lead zirconate titanate described above contains a large amount of lead, a piezoelectric material in which the lead content is suppressed is required from the viewpoint of environmental problems. As a piezoelectric material not containing lead, for example, there is BiFeO ₃ having a perovskite structure represented by ABO ₃ .

Here, the orientation of the crystal of the piezoelectric layer, is believed to affect the liquid jet characteristics such as displacement and stability, it is desired that the piezoelectric layer to the desired orientation, BiFeO ₃ based This piezoelectric material has a problem that it is difficult to form an alignment film on a noble metal such as platinum or iridium used as an electrode material. Such a problem is not limited to a liquid jet head typified by an ink jet recording head, and similarly exists in a piezoelectric element such as an actuator device mounted in another device.

  In view of such circumstances, the present invention provides a method for manufacturing a liquid ejecting head, a liquid ejecting apparatus, a method for manufacturing a piezoelectric element, and a method for forming a piezoelectric film having a piezoelectric layer with a small environmental load and preferentially oriented in the (100) plane. It aims at providing the manufacturing method of a composition.

An aspect of the present invention that solves the above-described problem is a method of manufacturing a liquid ejecting head having a pressure generating chamber that communicates with a nozzle opening that ejects liquid and a piezoelectric element that causes a pressure change in the pressure generating chamber. A step of forming a platinum film made of platinum preferentially oriented on the (111) plane; and an xylene solution of an organometallic compound containing Fe, Bi, La, Fe, and Mn and containing at least La and Fe on the platinum film. A step of forming a piezoelectric precursor film with a composition for forming a piezoelectric film obtained by mixing a xylene solution of an organometallic compound contained therein, and a piezoelectric layer is formed by firing the piezoelectric precursor film And a step of forming an electrode on the piezoelectric layer.
In such an embodiment, a piezoelectric film forming composition obtained by mixing a xylene solution of an organometallic compound containing Bi, La, Fe, and Mn and containing at least La and a xylene solution of an organometallic compound containing Fe is provided. The piezoelectric layer can be preferentially oriented to the (100) plane by forming a piezoelectric layer on the platinum film made of platinum preferentially oriented to the (111) plane. Moreover, since the lead content in the piezoelectric layer can be suppressed, the load on the environment can be reduced. “Preferentially oriented in the (100) plane” means that all the crystals are oriented in the (100) plane and most crystals (for example, 90% or more) are oriented in the (100) plane. Including the case where Similarly, “preferentially oriented in the (111) plane” means that all the crystals are oriented in the (111) plane and that most crystals (for example, 90% or more) are in the (111) plane. And the case where it is oriented.

  In the step of forming a platinum film made of platinum preferentially oriented on the (111) plane, the platinum film is formed on a titanium film made of titanium, and the piezoelectric precursor film is baked to form a piezoelectric film. The step of forming the body layer is preferably performed in an inert gas atmosphere. According to this, it is possible to easily manufacture a liquid jet head having a piezoelectric layer with reduced environmental load and preferentially oriented in the (100) plane.

  The piezoelectric film-forming composition is obtained by mixing an octane solution or xylene solution of an organometallic compound containing Bi and an octane solution or xylene solution of an organometallic compound containing Mn. It is preferable. According to this, by using a composition for forming a piezoelectric film in which an octane solution or xylene solution of an organometallic compound containing Bi or Mn is mixed, the environmental load is reduced and the (100) plane is preferentially oriented. A piezoelectric layer can be manufactured. For example, by using a composition for forming a piezoelectric film in which an octane solution of an organometallic compound containing Bi and an octane solution of an organometallic compound containing Mn are mixed, the burden on the environment is reduced and the (100) plane In addition, the piezoelectric layer preferentially oriented can be formed, the storage stability and wettability of the piezoelectric film-forming composition are improved, and uneven coating of the piezoelectric precursor film can be suppressed.

  The piezoelectric precursor film forming composition may contain diethanolamine. For example, the xylene solution of the organometallic compound containing La may contain diethanolamine. According to this, it is possible to form a piezoelectric layer preferentially oriented in the (100) plane with reduced environmental load, and the formed piezoelectric precursor film can be thickened, thereby suppressing the manufacturing cost. be able to.

  According to another aspect of the invention, there is provided a liquid ejecting apparatus including the liquid ejecting head manufactured by the method of manufacturing a liquid ejecting head according to the above aspect. According to this, a liquid ejecting apparatus having a piezoelectric layer with reduced environmental load and preferentially oriented in the (100) plane is obtained.

  Another aspect of the present invention includes a step of forming a platinum film made of platinum preferentially oriented in the (111) plane, and Bi, La, Fe, and Mn are included on the platinum film, and at least La is contained. A step of forming a piezoelectric precursor film by a composition for forming a piezoelectric film obtained by mixing a xylene solution of an organometallic compound containing and a xylene solution of an organometallic compound containing Fe, and the piezoelectric precursor film There is provided a method for manufacturing a piezoelectric element, comprising: a step of forming a piezoelectric layer by firing the substrate; and a step of forming an electrode on the piezoelectric layer. According to this, a composition for forming a piezoelectric film obtained by mixing a xylene solution of an organometallic compound containing Bi, La, Fe, Mn and containing at least La and a xylene solution of an organometallic compound containing Fe is obtained. The piezoelectric layer can be preferentially oriented to the (100) plane by forming a piezoelectric layer on the platinum film made of platinum preferentially oriented to the (111) plane. Moreover, since the lead content in the piezoelectric layer can be suppressed, the load on the environment can be reduced.

  In another embodiment of the present invention, a xylene solution of an organometallic compound containing La, a xylene solution of an organometallic compound containing Fe, a solution of an organometallic compound containing Bi, and a solution of an organometallic compound containing Fe are provided. It is in the manufacturing method of the composition for piezoelectric film formation characterized by mixing. By using the composition for forming a piezoelectric film manufactured by this manufacturing method, a piezoelectric layer preferentially oriented in the (100) plane can be formed. Moreover, since the lead content can be suppressed, the burden on the environment can be reduced.

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. 3 is a cross-sectional view of the recording head according to the first embodiment. It is a figure showing the PV curve of the sample 1. FIG. It is a figure showing the PV curve of the sample 2. FIG. 5 is a diagram illustrating a PV curve of Sample 3. FIG. 5 is a diagram illustrating a PV curve of Sample 4. FIG. 6 is a diagram illustrating a PV curve of Sample 5. FIG. 10 is a diagram illustrating a PV curve of Sample 6. FIG. It is a figure showing the PV curve of the sample 7. FIG. 5 is a diagram illustrating a PV curve of Sample 8. FIG. It is a figure showing the PV curve of the sample 9. FIG. 4 is a diagram illustrating a PV curve of Sample 10. FIG. 5 is a diagram illustrating a PV curve of Sample 11. FIG. 5 is a diagram illustrating a PV curve of Sample 12. FIG. It is a figure showing the PV curve of the sample 13. FIG. 5 is a diagram illustrating a PV curve of Sample 14. FIG. 5 is a diagram illustrating a PV curve of Sample 15. 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. 5 is a cross-sectional view illustrating a manufacturing process of the recording head according to Embodiment 1. FIG. It is a figure which shows the X-ray-diffraction pattern of Examples 1-2 and Comparative Examples 1-2. It is a figure which shows the X-ray-diffraction pattern of Examples 1-2 and Comparative Examples 3-4. It is a figure which shows the X-ray-diffraction pattern of Example 4 and Example 5. FIG. It is the SEM photograph which observed the cross section and surface of Examples 1-2 and Comparative Examples 1-2. It is the SEM photograph which observed the cross section and surface of Example 1 and Comparative Example 3. It is the SEM photograph which observed the section and surface of Example 4 and Example 5. It is a figure which shows the TG measurement result of Examples 1-2 and Comparative Examples 1-2. It is a figure which shows the TG measurement result of Example 1 and Comparative Example 3. It is a figure which shows the PV curve of Examples 1-2 and the comparative example 1. FIG. It is a figure which shows the PV curve of Example 1 and Comparative Example 3. It is a figure which shows the PV curve of Example 4 and Example 5. 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 manufactured by a manufacturing method according to Embodiment 1 of the present invention, and FIG. 2 is a plan view of FIG. 3 is a cross-sectional view taken along the line AA ′ of FIG. 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, the elastic film 50 is formed on the side opposite to the opening surface of the flow path forming substrate 10 as described above, and the insulator film 55 made of zirconium oxide is formed on the elastic film 50. ing.

  Further, on the insulator film 55, a first electrode 60, a piezoelectric layer 70 which is a thin film having a thickness of 2 μm or less, preferably 0.3 to 1 μm, and a second electrode 80 are laminated. Thus, the piezoelectric element 300 is configured. 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 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. Also, here, the piezoelectric element 300 and the diaphragm that is displaced by driving the piezoelectric element 300 are collectively referred to as an actuator device. In the above-described example, the elastic film 50, the insulator film 55, and the first electrode 60 function as a vibration plate. However, the present invention is not limited to this, and for example, the elastic film 50 and the insulator film 55 are provided. It does not have to be. Further, the piezoelectric element 300 itself may substantially serve as a diaphragm.

In the present embodiment, the first electrode 60 includes platinum preferentially oriented in the (111) plane. In the present embodiment, the piezoelectric layer 70 is formed using a predetermined piezoelectric film forming composition, which will be described in detail later, and includes bismuth (Bi), lanthanum (La), iron (Fe ) And manganese (Mn), that is, a composite oxide having a perovskite structure containing bismuth lanthanum iron manganate. Note that the A site of the perovskite structure, that is, the ABO ₃ type structure is 12-coordinated with oxygen, and the B site is 6-coordinated with oxygen to form an octahedron. Bi and La are located at the site, and Fe and Mn are located at the B site.

  In addition, since the piezoelectric layer 70 is formed using a predetermined piezoelectric film forming composition described later, as shown in a test example described later, the crystal is preferentially oriented in the (100) plane, The piezoelectric element 300 has a good hysteresis characteristic and is a good pressure generating means for an ink jet recording head.

The piezoelectric layer 70 containing bismuth (Bi), lanthanum (La), iron (Fe), and manganese (Mn) preferably has a composition ratio represented by the following general formula (1). By setting the composition ratio represented by the following general formula (1), the piezoelectric layer 70 can be made a ferroelectric substance. As described above, if the piezoelectric layer is the piezoelectric layer 70, the amount of strain can be easily controlled. For example, when a piezoelectric element is used in a liquid ejecting head or the like, the size of the ink droplets to be discharged can be easily set. Can be controlled. Note that the composite oxide having a perovskite structure including Bi, La, Fe, and Mn exhibited different characteristics such as a ferroelectric, an antiferroelectric, and a paraelectric depending on the composition ratio. Results of creating piezoelectric elements (samples 1 to 18) with different composition ratios of the following general formula (1), applying a 25 V or 30 V triangular wave, and determining the relationship of P (polarization amount) −V (voltage) Are shown in FIGS. 4 to 18 and the composition is shown in Table 1. Samples 16 to 18 were too leaky to be measured and could not be used as piezoelectric materials. As shown in FIGS. 4 to 14, in samples 1 to 11 in the ranges of 0.10 ≦ x ≦ 0.20 and 0.01 ≦ y ≦ 0.09, the hysteresis loop shape characteristic of the ferroelectric has Observed. Therefore, in the samples 1 to 11, since the distortion amount linearly changes with respect to the applied voltage, the distortion amount can be easily controlled. On the other hand, samples 12 to 14 outside the range of 0.10 ≦ x ≦ 0.20 and 0.01 ≦ y ≦ 0.09 in the following general formula (1) are antiferroelectric as shown in FIGS. Since the double hysteresis having two hysteresis loop shapes in the positive electric field direction and the negative electric field direction characteristic of the body was observed, it is an antiferroelectric material, and the sample 15 is a paraelectric material as shown in FIG. In addition, as described above, samples 16 to 18 were too leaky to be used as a piezoelectric material, and none of samples 12 to 18 was a ferroelectric material.
_{(Bi 1-x, La x} ) (Fe 1-y, Mn y) O 3 (1)
(0.10 ≦ x ≦ 0.20, 0.01 ≦ y ≦ 0.09)

  Here, when an antiferroelectric material, which is a substance in which spontaneous polarization is arranged in a staggered manner, that is, a material that exhibits an electric field induced phase transition is used as a piezoelectric layer, it exhibits an electric field induced phase transition at a certain applied voltage or more and a large distortion Therefore, it is possible to obtain a large strain exceeding that of the ferroelectric material, but it is not driven below a certain voltage, and the amount of strain does not change linearly with respect to the voltage. The electric field induced phase transition is a phase transition caused by an electric field, and means a phase transition from an antiferroelectric phase to a ferroelectric phase or a phase transition from a ferroelectric phase to an antiferroelectric phase. The ferroelectric phase is a state where the polarization axes are aligned in the same direction, and the anti-ferroelectric phase is a state where the polarization axes are aligned alternately. For example, the phase transition from the antiferroelectric phase to the ferroelectric phase is caused by the fact that the polarization axes arranged in a staggered manner in the antiferroelectric phase rotate 180 degrees, so that the polarization axes become the same direction and become a ferroelectric phase. A strain generated by expansion or expansion / contraction of the lattice due to the electric field induced phase transition is a phase transition strain generated by the electric field induced phase transition. Antiferroelectric materials exhibit such an electric field-induced phase transition, in other words, the polarization axes are staggered in the absence of an electric field, and the polarization axes are rotated in the same direction by the electric field. It is a ferroelectric material. Such an antiferroelectric material has a double hysteresis having two hysteresis loop shapes in a positive electric field direction and a negative electric field direction in a PV curve indicating a relationship between the polarization amount P and the voltage V of the antiferroelectric material. Become. A region where the amount of polarization changes abruptly is a portion where the phase transition from the ferroelectric phase to the antiferroelectric phase or the phase transition from the antiferroelectric phase to the ferroelectric phase occurs.

  On the other hand, in the ferroelectric material, the PV curve does not become double hysteresis unlike the antiferroelectric material, and the strain amount changes linearly with respect to the applied voltage by aligning the polarization direction in one direction. Therefore, since it is easy to control the amount of distortion, it is easy to control the size of droplets to be ejected, and a single piezoelectric element generates both small amplitude vibrations that generate fine vibrations and large amplitude vibrations that generate large excluded volumes. be able to.

  When the piezoelectric layer 70 is measured by powder X-ray diffraction, in the diffraction pattern, a diffraction peak attributed to a phase exhibiting ferroelectricity (ferroelectric phase) and a phase exhibiting antiferroelectricity (antiferroelectric) It is preferred that the diffraction peaks attributed to the (dielectric phase) are observed simultaneously. Thus, a diffraction peak attributed to a phase exhibiting ferroelectricity and a diffraction peak attributed to a phase exhibiting antiferroelectricity are simultaneously observed, that is, a composition phase of an antiferroelectric phase and a ferroelectric phase. When the piezoelectric layer 70 is the boundary (MPB), a piezoelectric element with a large amount of strain can be obtained. In the general formula (1), the piezoelectric layer 70 preferably satisfies 0.17 ≦ x ≦ 0.20, and more preferably 0.19 ≦ x ≦ 0.20. In this range, when powder X-ray diffraction measurement is performed, a diffraction peak attributed to a phase exhibiting ferroelectricity (ferroelectric phase) and a diffraction attributed to a phase exhibiting antiferroelectricity (antiferroelectric phase) Peaks are observed at the same time, indicating both antiferroelectric and ferroelectric phases. Therefore, M. of antiferroelectric phase and ferroelectric phase. P. B. Therefore, a piezoelectric element with a large amount of strain can be obtained.

  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 and the lead electrode 90, the protective substrate 30 having the manifold portion 31 constituting at least a part of the manifold 100 is bonded. It is joined via the agent 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 a manifold and 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 are provided. 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 first electrode 60, and the piezoelectric film are applied. By flexing and deforming the body layer 70, the pressure in each pressure generating chamber 12 increases and ink droplets are ejected from the nozzle openings 21.

  Next, an example of a method for manufacturing the ink jet recording head of this embodiment will be described with reference to FIGS. 19 to 23 are cross-sectional views in the longitudinal direction of the pressure generating chamber.

First, as shown in FIG. 19A, a silicon dioxide film made of silicon dioxide (SiO ₂ ) constituting the elastic film 50 is formed by thermal oxidation or the like on the surface of a flow path forming substrate wafer 110 that is a silicon wafer. To do. Next, as shown in FIG. 19B, an insulator film 55 made of zirconium oxide is formed on the elastic film 50 by a reactive sputtering method, thermal oxidation, or the like. Next, an adhesion layer 56 made of titanium or the like is formed on the insulator film 55 by a DC sputtering method, an ion sputtering method, or the like.

  Next, as shown in FIG. 20A, a platinum film 57 made of platinum preferentially oriented on the (111) plane is formed on the entire surface of the adhesion layer 56 by sputtering or the like. This platinum film 57 becomes the first electrode 60.

  Next, the piezoelectric layer 70 is laminated on the platinum film 57. 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. Specifically, a piezoelectric precursor film is formed with a predetermined piezoelectric film forming composition (precursor solution), and the piezoelectric precursor film is baked and crystallized to form the piezoelectric layer 70. it can.

  In the present invention, the piezoelectric film-forming composition contains Bi, La, Fe, and Mn, and is an xylene solution of an organometallic compound containing at least La and an organometallic compound containing Fe. It is obtained by mixing a xylene solution. Specifically, a solution in which an organometallic compound containing La is dissolved or dispersed in a solvent containing xylene, a solution in which an organometallic compound containing Fe is dissolved or dispersed in a solvent containing xylene, and an organic containing Bi A solution obtained by dissolving or dispersing a metal compound in an organic solvent and a solution obtained by dissolving or dispersing an organometallic compound containing Mn in an organic solvent are used as a raw material solution, and a sol or MOD obtained by mixing these raw material solutions. A solution (precursor solution).

  Thus, by setting the solvent of the La raw material solution and the Fe raw material solution to contain xylene (for example, 60% by mass or more of xylene), crystals are preferentially oriented on the (100) plane, and Bi, La, Fe And a piezoelectric layer 70 made of a piezoelectric material having a perovskite structure containing Mn. On the other hand, when the solvent of the La raw material solution and the Fe raw material solution does not contain xylene, the piezoelectric layer cannot be preferentially oriented to the (100) plane. For example, the La raw material solution and the Fe raw material solution When the solvent is octane, butanol or the like, a random piezoelectric layer in which crystals are oriented on the (100) plane and the (111) plane is formed, and a piezoelectric element having no good hysteresis characteristics is obtained. What is important here is that the solvent of the La raw material solution and the Fe raw material solution contains xylene. For example, xylene is used as the solvent of the Bi raw material solution or the Mn raw material solution, and the raw material solutions of the respective elements are mixed. Even if the mixed solution as a whole contains xylene, when the solvent of the La raw material solution and the Fe raw material solution does not contain xylene, the piezoelectric layer (100 ) It cannot be preferentially oriented on the surface. Thus, although the mechanism by which the orientation of the piezoelectric layer produced by the solvent of the La raw material solution or the Fe raw material solution differs is unknown, La and Fe are different depending on whether the solvent contains xylene or not. This is presumed to be due to the different forms. In addition, although the metal concentration of each raw material solution of Bi, La, Fe, and Mn is not specifically limited, For example, what is necessary is just to be about 2-20 mass%. Further, the mixing ratio of the Bi raw material solution, the La raw material solution, the Fe raw material solution, and the Mn raw material solution is not particularly limited, and Bi, La, Fe, and Mn may be mixed so as to have a desired molar ratio. For example, Bi raw material solution: La raw material solution: Fe raw material solution: Mn raw material solution = 30 to 45: 5 to 20:45 to 55: 0.5 to 4 (volume ratio, moles with the same raw material) (If it is a concentration)

  Examples of the solvent of the organometallic compound solution containing Bi and Mn, that is, the solvent of the Bi raw material solution and the solvent of the Mn raw material solution include, for example, octane, xylene and a mixed solvent thereof. Preferably it contains octane. When octane is used as the solvent for the Bi or Mn raw material solution, the storage stability of the composition for forming a piezoelectric film is improved, and there is no uneven coating of the formed piezoelectric precursor film. This is because the piezoelectric layer 70 can be formed.

  Further, the composition for forming a piezoelectric film may contain diethanolamine. When diethanolamine is contained, the formed piezoelectric precursor film can be thickened. Therefore, when the piezoelectric layer 70 is formed by laminating a plurality of piezoelectric precursor films, the relatively thick piezoelectric layer 70 can be manufactured even if the number of times of lamination of the piezoelectric precursor films is small. Manufacturing cost can be suppressed.

  In addition, the composition for forming a piezoelectric film may contain polyethylene glycol. When polyethylene glycol is contained, the occurrence of cracks in the formed piezoelectric layer 70 can be suppressed.

  Diethanolamine or polyethylene glycol may be contained in a raw material solution, for example, a xylene solution of an organometallic compound containing La, or added to a mixed solution obtained by mixing Bi, La, Fe, and Mn raw material solutions. You may make it do. The mixing ratio of diethanolamine or polyethylene glycol is not particularly limited, but when it is contained in a La raw material solution or a Fe raw material solution, that is, a xylene solution of an organometallic compound containing La or a xylene solution of an organometallic compound containing Fe Preferably, the xylene content is 60% by mass or more based on the solvent of each raw material solution. Moreover, when adding diethanolamine and polyethylene glycol to the mixed solution obtained by mixing the raw material solutions of Bi, La, Fe, and Mn, the mixed solution: diethanolamine or polyethylene glycol = 100: 1 to 10 (volume ratio) And it is sufficient. Even if diethanolamine or polyethylene glycol is included in the composition for forming a piezoelectric film, the (100) plane preferential orientation and denseness of the crystals of the piezoelectric layer 70 can be maintained. Further, the diethanolamine or polyethylene glycol disappears upon firing and does not remain in the piezoelectric layer 70, like the solvent of the raw material solution.

  As the organometallic compound containing Bi, La, Fe, and Mn, for example, metal alkoxide, organic acid salt, 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 La include lanthanum 2-ethylhexanoate. Examples of the organometallic compound containing Fe include iron 2-ethylhexanoate. Examples of the organometallic compound containing Mn include manganese 2-ethylhexanoate. Of course, an organometallic compound containing two or more of Bi, La, Fe and Mn may be used.

  As a specific example of the procedure for forming the piezoelectric layer 70, first, as shown in FIG. 20B, the piezoelectric film forming composition (precursor solution) is applied onto the platinum film 57 by spin coating. The piezoelectric precursor film 71 is formed by coating using a dip coating method, an ink jet method, or the like (coating step).

Next, the piezoelectric precursor film 71 is heated to a predetermined temperature and dried for a predetermined time (drying step). Next, the dried piezoelectric precursor film 71 is degreased by heating it to a predetermined temperature and holding it for a predetermined 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. 20 (c), the piezoelectric precursor film 71 is heated to a predetermined temperature, for example, about 600 to 800 ° C. and held for a certain period of time in an inert gas atmosphere. The piezoelectric film 72 is formed (firing process). Here, the inert gas atmosphere is a rare gas such as helium or argon, an inert gas such as nitrogen gas, or a mixed gas atmosphere thereof. It may be in a state where the inside of the heating apparatus is replaced with an inert gas or in a state where an inert gas is allowed to flow in the heating apparatus. Further, the inert gas concentration may not be 100%, for example, the oxygen concentration is less than 20%. If this firing step is not performed in an inert gas atmosphere, the piezoelectric layer 70 cannot be preferentially oriented in the (100) plane.

  In addition, as a heating apparatus used by a drying process, a degreasing process, and a baking process, the RTA (Rapid Thermal Annealing) apparatus, a hotplate, etc. which heat by irradiation of an infrared lamp are mentioned, for example.

  Next, as shown in FIG. 21A, the side surfaces of 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. As shown in FIG. 21B, the piezoelectric layer 70 having a predetermined thickness composed of a plurality of layers of piezoelectric films 72 is formed. 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.

  Note that when passing through the step of crystallizing the piezoelectric precursor film 71, depending on the firing conditions, the platinum film 57 made of platinum contains platinum, and depending on the degree of titanium diffusion, platinum also contains titanium and titanium oxide. Become a layer. In addition, a layer containing titanium oxide may be formed between the platinum layer and the piezoelectric layer 70 by the diffused titanium. Moreover, a layer containing titanium oxide may be formed on the flow path forming substrate 10 side of the platinum layer by titanium that has not diffused. The layer containing titanium oxide is not limited to a complete layer shape, and may have an island shape, for example.

  After the piezoelectric layer 70 is formed in this way, as shown in FIG. 22A, 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 700 ° 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. 22B, a lead electrode 90 made of, for example, gold (Au) or the like is formed over the entire surface of the wafer 110 for flow path forming substrate, 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. 22 (c), a protective substrate wafer 130 that is a silicon wafer and serves as a plurality of protective substrates 30 is disposed 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. 23A, 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. 23B, the flow path forming substrate wafer 110 is anisotropically etched (wet etching) using an alkaline solution such as KOH through the mask film 52, whereby the piezoelectric element 300 is formed. 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
(Preparation of composition for forming piezoelectric film)
12% by weight octane solution of bismuth 2-ethylhexanoate, 2% by weight xylene solution of lanthanum 2-ethylhexanoate, 5% by weight xylene solution of iron 2-ethylhexanoate, 5% by weight octane of manganese 2-ethylhexanoate The solution was mixed at a volume ratio of 29: 35: 35: 1 to prepare a piezoelectric film forming composition (precursor solution).

(Creation of piezoelectric element)
First, a silicon dioxide film was formed on the surface of a single crystal silicon substrate by thermal oxidation. Next, a 400-nm-thick zirconium oxide film was formed on the silicon dioxide film by sputtering. Next, a 20 nm-thick titanium film was formed on the zirconium oxide film by sputtering. Next, a platinum film having a thickness of 130 nm was formed on the titanium film by sputtering.

  Next, a piezoelectric layer was formed on the platinum film by spin coating. The method is as follows. First, the piezoelectric film-forming composition (precursor solution) is dropped onto the substrate on which the platinum film is formed, and the piezoelectric body is first rotated at 500 rpm for 5 seconds and then at 1500 rpm for 30 seconds. A precursor film was formed (application process). Next, drying and degreasing were performed in air at 150 ° C. for 2 minutes and at 350 ° C. for 4 minutes (drying and degreasing process). After repeating this coating process, drying, and degreasing process three times, firing was performed at 650 ° C. for 2 minutes using Rapid Thermal Annealing (RTA) in which the inside of the heating apparatus was flowed with nitrogen at a flow rate of 5 L / min (baking process). This coating process, drying and degreasing process are repeated 3 times, and then the process of performing a baking process is performed 4 times, and then the heating apparatus is 650 ° C. with RTA flowed with nitrogen at a flow rate of 5 L / min. By baking for 5 minutes, a piezoelectric layer was formed by a total of 12 coatings. The piezoelectric layer as a whole had a thickness of 480 nm.

  Thereafter, a platinum film having a film thickness of 100 nm is formed as a second electrode on the piezoelectric layer by sputtering, and then baked at 650 ° C. for 5 minutes in an RTA flowed with nitrogen at a flow rate of 5 L / min. Thus, a piezoelectric element having a piezoelectric layer made of a composite oxide having a perovskite structure represented by the above general formula (1) where x = 0.19 and y = 0.03 was formed.

(Example 2)
Instead of a 2% by weight xylene solution of lanthanum 2-ethylhexanoate, a mixed solvent solution of 5% by weight xylene of lanthanum 2-ethylhexanoate, amyl alcohol and diethanolamine (xylene: amyl alcohol: diethanolamine = 70: 25: 5 A composition for forming a piezoelectric film (precursor solution) was prepared in the same manner as in Example 1 except that (mass ratio) was used. In the same manner as in Example 1, a silicon dioxide film, a zirconium oxide film, a titanium film, and a platinum film were sequentially formed on a single crystal silicon substrate. Next, a piezoelectric layer was formed on the platinum film by spin coating. The method is as follows. First, the piezoelectric film-forming composition (precursor solution) is dropped onto the substrate on which the platinum film is formed, and the piezoelectric body is first rotated at 500 rpm for 5 seconds and then at 1500 rpm for 30 seconds. A precursor film was formed (application process). Next, drying and degreasing were performed in air at 150 ° C. for 2 minutes and at 350 ° C. for 4 minutes (drying and degreasing process). After repeating this coating process, drying, and degreasing process twice, baking was performed at 650 ° C. for 2 minutes using Rapid Thermal Annealing (RTA) in which the inside of the heating apparatus was flowed with nitrogen at a flow rate of 5 L / min (baking process). This coating process, drying and degreasing process are repeated twice, and then the process of performing a baking process is performed three times. Thereafter, the inside of the heating apparatus is 650 ° C. with RTA flowed with nitrogen at a flow rate of 5 L / min. By baking for 5 minutes, a piezoelectric layer was formed by a total of 6 coatings. The thickness of the piezoelectric layer was 450 nm.

(Example 3)
A 12% by weight xylene solution of bismuth 2-ethylhexanoate was used instead of the 12% by weight octane solution of bismuth 2-ethylhexanoate, and 2-ethylhexanoic acid was used instead of the 5% by weight octane solution of manganese 2-ethylhexanoate. A piezoelectric element was formed in the same manner as in Example 1 except that a 5 mass% xylene solution of manganese was used. The thickness of the piezoelectric layer was 480 nm.

Example 4
To the composition for forming a piezoelectric film of Example 1, diethanolamine was added so that the composition for forming a piezoelectric film of Example 1: diethanolamine = 95: 5 (volume ratio), and the piezoelectric material of Example 4 was added. A film-forming composition (precursor solution) was obtained. And the piezoelectric element was formed by the method similar to Example 1 using this composition for piezoelectric film formation. The thickness of the piezoelectric layer was 570 nm.

(Example 5)
Polyethylene glycol (molecular weight 400) is added to the piezoelectric film forming composition of Example 1 so that the piezoelectric film forming composition of Example 1: polyethylene glycol = 97.5: 2.5 (volume ratio). To obtain a composition for forming a piezoelectric film (precursor solution) of Example 5. And the piezoelectric element was formed by the method similar to Example 1 using this composition for piezoelectric film formation. The thickness of the piezoelectric layer was 480 nm.

(Comparative Example 1)
A piezoelectric element was formed in the same manner as in Example 1 except that a 2% by mass octane solution of lanthanum 2-ethylhexanoate was used instead of the 2% by mass xylene solution of lanthanum 2-ethylhexanoate. The thickness of the piezoelectric layer was 600 nm.

(Comparative Example 2)
A piezoelectric element was formed in the same manner as in Example 1 except that a 3% by weight butanol solution of lanthanum 2-ethylhexanoate was used instead of the 2% by weight xylene solution of lanthanum 2-ethylhexanoate. The thickness of the piezoelectric layer was 630 nm.

(Comparative Example 3)
Instead of a 5 mass% xylene solution of iron 2-ethylhexanoate, an octane solution of 10 mass% (Bi: Fe = 1: 1 (mass ratio)) of iron 2-ethylhexanoate and bismuth 2-ethylhexanoate was used. A piezoelectric element was formed in the same manner as in Example 1 except that it was used. The thickness of the piezoelectric layer was 450 nm.

(Comparative Example 4)
Instead of a 12% by weight octane solution of bismuth 2-ethylhexanoate and a 5% by weight xylene solution of iron 2-ethylhexanoate, 10% by weight of iron 2-ethylhexanoate and bismuth 2-ethylhexanoate (Bi: Fe = 1: 1 (mass ratio)) A piezoelectric element was formed in the same manner as in Example 2 except that an octane solution was used. The thickness of the piezoelectric layer was 390 nm.

(Comparative Example 5)
A piezoelectric element was formed in the same manner as in Example 3 except that a 2% by mass octane solution of lanthanum 2-ethylhexanoate was used instead of the 2% by mass xylene solution of lanthanum 2-ethylhexanoate. The thickness of the piezoelectric layer was 600 nm.

(Test Example 1)
For the piezoelectric elements of Examples 1 to 5 and Comparative Examples 1 to 5, “D8 Discover” manufactured by Bruker AXS was used, CuKα ray was used as the X-ray source, and the powder X-ray diffraction pattern of the piezoelectric layer at room temperature Asked. Table 2 shows the results of evaluating the orientation, where ◯ indicates that the (100) plane is preferentially oriented, and x indicates that the (100) plane is not preferentially oriented. Moreover, the X-ray diffraction pattern which is a figure which shows the correlation of diffraction intensity-diffraction angle 2 (theta), Examples 1-2 and Comparative Examples 1-2 are shown in FIG. 24, Examples 1-2 and Comparative Example 3 are shown in FIG. To 4 and FIG. 26 shows Example 4 and Example 5 as an example of the results. In all of Examples 1 to 5 and Comparative Examples 1 to 5, diffraction peaks derived from the perovskite structure (ABO ₃ type structure) were observed, and the piezoelectric layers of Examples 1 to 5 and Comparative Examples 1 to 5 were perovskite. A mold structure was formed.

As shown in Table 2 and FIG. 24, the powder X-ray diffraction patterns differ depending on the solvent of the La raw material solution, and in Examples 1 to 3 in which the solvent of the La raw material solution contains xylene, the (100) plane is preferentially oriented. It can be seen that the alignment film is formed. Specifically, Examples 1-3, 20 ° <2θ <intensity of a diffraction peak derived from ABO ₃ observed at 25 °, 20 ° <2θ <diffraction peaks derived from ABO ₃ observed at 50 ° It was 90% or more of the sum of the area strengths, and the alignment film was preferentially oriented on the (100) plane. On the other hand, in Comparative Example 1 and Comparative Example 5 in which the solvent of the La raw material solution was octane and Comparative Example 2 in which butanol was used, the orientation was random. As shown in FIG. 24, Example 1 shows a peak in which a diffraction peak near 2θ = 46.1 ° indicating a ferroelectric phase and a diffraction peak near 2θ = 46.5 ° indicating an antiferroelectric phase are mixed. Therefore, it can be seen that Example 1 is a composition phase boundary (MPB) in which both the structure caused by the ferroelectric substance and the structure caused by the antiferroelectric substance coexist.

Also, as shown in Table 2 and FIG. 25, the powder X-ray diffraction pattern differs depending on the solvent of the Fe raw material solution, and in Examples 1 to 3 in which the solvent of the Fe raw material solution contains xylene, It can be seen that the orientation film is preferentially oriented. Specifically, Examples 1-3, 20 ° <2θ <intensity of a diffraction peak derived from ABO ₃ observed at 25 °, 20 ° <2θ <diffraction peaks derived from ABO ₃ observed at 50 ° In Comparative Example 3 and Comparative Example 4 in which the solvent of the Fe raw material solution is octane, the orientation film was 90% or more of the total area strength of No. 1 and was preferentially oriented on the (100) plane. Was random.

  Here, in Example 1 preferentially oriented in the (100) plane, as in Comparative Example 5 in which the orientation is random, the piezoelectric film forming composition, that is, the solvent of the mixed solution in which the raw material solutions of each element are mixed However, it is xylene: octane = 7: 3 (volume ratio). Therefore, the solvent of the entire mixed solution is not important, and the solvent of the raw material solution of La and Fe is xylene in order to preferentially orient the crystals of the piezoelectric layer 70 in the (100) plane. I can say that.

  As shown in FIG. 26, Example 4 in which diethanolamine is added to the composition for forming a piezoelectric film of Example 1 and Example 5 in which polyethylene glycol is added are similar to the powder X-ray diffraction pattern of Example 1. It was confirmed that (100) plane orientation can be maintained even when diethanolamine or polyethylene glycol is added to the mixed solution.

(Test Example 2)
In Examples 1 to 5 and Comparative Examples 1 to 5, before forming the second electrode, the cross section and the surface of the piezoelectric layer were observed with a scanning electron microscope (SEM) at 50000 times. Table 2 shows the results of evaluation of film roughness, where the surface of the piezoelectric layer and the cross section are not rough and are dense, and the case where the piezoelectric layer is rough is x. 27 (a) (cross section), FIG. 27 (b) (surface), FIG. 28 (a) (cross section) and FIG. 28 (b) (surface), Example 1 is shown in FIG. 27 (c) (cross section). ) And FIG. 27 (d) (surface), Example 2 in FIG. 27 (e) (cross section) and FIG. 27 (f) (surface), Comparative Example 1, FIG. 27 (g) (cross section) and FIG. Comparative example 2 is shown in (h) (surface), Comparative example 3 is shown in FIG. 28 (c) (cross section) and FIG. 28 (d) (surface), and FIG. 29 (a) (cross section) and FIG. Example 4 is shown on the surface), and Example 5 is shown in FIG. 29 (c) (cross section) and FIG. 29 (d) (surface).

  As shown in Table 2 and FIG. 27, in Examples 1 to 3 in which the solvent of the La raw material solution contains xylene, the solvent of the La raw material solution is octane, whereas it has a very dense film structure. In Comparative Example 1 and Comparative Example 5 and Comparative Example 2 which is butanol, many vacancies were observed in the film, and the surface morphology was greatly roughened.

  In addition, as shown in FIG. 28, in Examples 1 to 3 in which the solvent of the Fe raw material solution contains xylene, the comparative example in which the solvent of the Fe raw material solution is octane is a very dense film structure. In No. 3 and Comparative Example 4, many vacancies were observed in the film, and the surface morphology was greatly roughened.

  As shown in FIG. 29, Example 4 in which diethanolamine was added to the composition for forming a piezoelectric film of Example 1 and Example 5 in which polyethylene glycol was added were very dense films as in Example 1. It was a structure.

(Test Example 3)
For each of the piezoelectric film forming compositions of Examples 1 to 5 and Comparative Examples 1 to 5, the weight reduction rate was measured by thermogravimetry (TG measurement). The mass change with respect to temperature was measured. As an example of the results, Example 1 is shown in FIGS. 30 (a) and 31 (a), Example 2 is shown in FIG. 30 (b), Comparative Example 1 is shown in FIG. 30 (c), and FIG. Comparative example 2 is shown in FIG. 31 (b). As shown in FIG.30 and FIG.31, all of Examples 1-5 and Comparative Examples 1-5 are 350-400 degreeC or more, and the weight is constant, In Examples 1-5 and Comparative Examples 1-5, The temperature of 350 ° C. in the drying and degreasing process was confirmed to be a sufficient temperature. As a cause of rough orientation difference and morphology of the piezoelectric layer, it is generally considered that the temperature in the drying and degreasing process is low. From the result of Test Example 3, the difference in orientation of Test Example 1, It is considered that the roughness of the morphology of the piezoelectric layer of Test Example 2 is not caused by the low temperature in the drying and degreasing processes.

(Test Example 4)
When the pH of each of the piezoelectric film forming compositions of Examples 1 and 2 and Comparative Examples 1 and 2 was measured, Example 1 was 5.4, Example 2 was 8.0, Comparative Example 1 and The comparative example 2 was 4.9. From the results of Test Example 4, there was no particular correlation between the pH of the composition for forming a piezoelectric film, the difference in the orientation of the piezoelectric layer, and the roughness of the morphology.

(Test Example 5)
For each of the piezoelectric elements of Examples 1 to 5 and Comparative Examples 1 to 5, “FCE-1A” manufactured by Toyo Technica Co., Ltd., using an electrode pattern of φ = 400 μm, applying a triangular wave with a frequency of 1 kHz at room temperature, and polarization The relationship between the amount and voltage (P-V curve) was determined. Table 2 shows the results of the evaluation of the hysteresis characteristics, where ◯ indicates that the hysteresis was good, and x indicates that the hysteresis was not good. Also, as an example of the results, Example 1 is shown in FIGS. 32 (a) and 33 (a), Example 2 is shown in FIG. 32 (b), Comparative Example 1 is shown in FIG. 32 (c), and FIG. ) Shows Comparative Example 3, FIG. 34 (a) shows Example 4, and FIG. 34 (b) shows Example 5. In Comparative Example 2, measurement was not possible due to a short circuit.

  As shown in FIG. 32, in Examples 1 to 3 in which the solvent of the La raw material solution contains xylene, good hysteresis was obtained, whereas Comparative Example 1 and Comparative Example in which the solvent of the La raw material solution was octane. In No. 5, the hysteresis tends to close and the amount of displacement is small, and in Comparative Example 2 where the solvent is butanol, a short circuit occurs and the hysteresis is not good. In addition, as shown in FIG. 33, in Examples 1 to 3 in which the solvent of the Fe raw material solution contains xylene, good hysteresis was obtained, while in Comparative Example 3 in which the solvent of the Fe raw material solution was octane, In Comparative Example 4, the hysteresis tends to close and the amount of displacement is small, and the hysteresis is not good. The reason why Comparative Examples 1 to 5 did not exhibit good hysteresis is considered to be due to random orientation or morphological roughness as shown in Test Example 1 and Test Example 2.

  As shown in FIG. 34, Example 4 in which diethanolamine is added to the composition for forming a piezoelectric film of Example 1 and Example 5 in which polyethylene glycol is added have very good hysteresis as in Example 1. Met.

(Test Example 6)
The piezoelectric film forming compositions of Examples 1 to 5 and Comparative Examples 1 to 5 were left for 7 days. Table 2 shows the results of evaluating the storage stability of the composition for forming a piezoelectric film, with ◯ indicating that no precipitate was produced even after 7 days, and x indicating that the precipitate was formed. As a result, in the compositions for forming piezoelectric films of Examples 1, 2, 4, 5 and Comparative Examples 1 to 4, in which the solvent of the Bi raw material solution and the solvent of the Mn raw material solution are octane, no precipitate is generated. However, in Example 3 and Comparative Example 5 where the solvent of the Bi raw material solution and the solvent of the Mn raw material solution were xylene, solids were precipitated after 1 day from the production of the piezoelectric film forming composition. did. In each of the piezoelectric film forming compositions of Examples 1 to 5 and Comparative Examples 1 to 5, no precipitation occurred immediately after the production.

(Test Example 7)
For each of the piezoelectric precursor films of Examples 1 to 5 and Comparative Examples 1 to 5, the case where no striation (radial striped pattern) occurred was observed by visual observation, and the striation (radial striped pattern) was The resulting case was evaluated as x. Moreover, the case where application | coating nonuniformity did not arise in a piezoelectric material precursor film | membrane evaluated as (circle), and the case where application | coating nonuniformity (those resulting from foreign materials, such as a precipitate) produced, was evaluated as x. The results are shown in Table 2. As a result, in the piezoelectric precursor films of Examples 1, 2, 4, 5 and Comparative Examples 1 to 4 in which the solvent of the Bi raw material solution and the solvent of the Mn raw material solution are octane, striation and coating unevenness occur. This was a uniform piezoelectric precursor film. On the other hand, in Example 3 and Comparative Example 5 where the solvent of the Bi raw material solution and the solvent of the Mn raw material solution were xylene, striation did not occur, but coating unevenness occurred because of poor wettability.

  As described above, in Examples 1 to 5 where the solvent of the raw material solution of La and Fe is xylene, the piezoelectric layer is preferentially oriented in the (100) plane and dense, and the piezoelectric element has good hysteresis. It was something to draw. In Examples 2 and 4 in which diethanolamine was added to the solvent or mixed solution of the La raw material solution, a thicker film could be formed than in the case where no diethanolamine was added. In Examples 1, 2, 4 and 5 in which the raw material solutions of Bi and Mn are octane, the storage stability and wettability of the piezoelectric film forming composition are good, and the piezoelectric precursor film There was no coating unevenness, and a piezoelectric layer having a uniform thickness could be formed.

(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.

  Furthermore, in the above-described embodiment, the piezoelectric element 300 in which the first electrode 60, the piezoelectric layer 70, and the second electrode 80 are sequentially stacked on the substrate (the flow path forming substrate 10) is illustrated, but the present invention is not particularly limited thereto. For example, the present invention can also be applied to a longitudinal vibration type piezoelectric element in which piezoelectric materials and electrode forming materials are alternately stacked to expand and contract in the axial direction.

  In addition, the ink jet recording head of these embodiments constitutes a part of a recording head unit including an ink flow path communicating with an ink cartridge or the like, and is mounted on the ink jet recording apparatus. FIG. 35 is a schematic view showing an example of the ink jet recording apparatus.

  In the ink jet recording apparatus II shown in FIG. 35, the recording head units 1A and 1B having the ink jet recording head I are detachably provided with cartridges 2A and 2B constituting the 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 includes an ultrasonic device such as an ultrasonic transmitter, an ultrasonic motor, a piezoelectric transformer, an infrared sensor, and an ultrasonic wave. It can be applied to piezoelectric elements such as various sensors such as sensors, thermal sensors, pressure sensors, and pyroelectric sensors. Further, 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, 60 first electrode, 70 piezoelectric layer, 80 second electrode, 90 lead electrode, 100 manifold, 120 drive circuit, 300 piezoelectric element

Claims (8)

A method of manufacturing a liquid ejecting head having a pressure generating chamber communicating with a nozzle opening for ejecting liquid and a piezoelectric element for causing a pressure change in the pressure generating chamber,
Forming a platinum film made of platinum preferentially oriented in the (111) plane;
A composition for forming a piezoelectric film obtained by mixing a xylene solution of an organometallic compound containing Bi, La, Fe, and Mn and containing at least La and a xylene solution of an organometallic compound containing Fe on the platinum film. Forming a piezoelectric precursor film with a material;
Forming a piezoelectric layer by firing the piezoelectric precursor film;
And a step of forming an electrode on the piezoelectric layer. In the step of forming a platinum film made of platinum preferentially oriented on the (111) plane, the platinum film is formed on a titanium film made of titanium,
The method of manufacturing a liquid jet head according to claim 1, wherein the step of forming the piezoelectric layer by firing the piezoelectric precursor film is performed in an inert gas atmosphere.   The piezoelectric film forming composition is obtained by mixing an octane solution or xylene solution of an organometallic compound containing Bi and an octane solution or xylene solution of an organometallic compound containing Mn. The method for manufacturing a liquid jet head according to claim 1, wherein the liquid jet head is a liquid jet head.   The method for manufacturing a liquid ejecting head according to claim 1, wherein the composition for forming a piezoelectric precursor film includes diethanolamine.   The method for manufacturing a liquid jet head according to claim 4, wherein the xylene solution of the organometallic compound containing La contains diethanolamine.   A liquid ejecting apparatus comprising the liquid ejecting head manufactured by the method of manufacturing a liquid ejecting head according to claim 1. Forming a platinum film made of platinum preferentially oriented in the (111) plane;
A composition for forming a piezoelectric film obtained by mixing a xylene solution of an organometallic compound containing Bi, La, Fe, and Mn and containing at least La and a xylene solution of an organometallic compound containing Fe on the platinum film. Forming a piezoelectric precursor film with a material;
Forming a piezoelectric layer by firing the piezoelectric precursor film;
And a step of forming an electrode on the piezoelectric layer.   A piezoelectric comprising mixing a xylene solution of an organometallic compound containing La, a xylene solution of an organometallic compound containing Fe, a solution of an organometallic compound containing Bi, and a solution of an organometallic compound containing Fe The manufacturing method of the composition for body film formation.