KR100816169B1 - Method for manufacturing actuator device and actuator device and liquid spray head and liquid ejection device - Google Patents

Abstract

Provided are a method of manufacturing an actuator device, an actuator device, a liquid jet head, and a liquid jet device that can maintain a piezoelectric property of a piezoelectric layer well and can prevent peeling of an upper electrode.

Forming a vibrating plate on the substrate; and forming a piezoelectric element comprising a lower electrode, a piezoelectric layer, and an upper electrode on the vibrating plate; and forming a piezoelectric element in the sputtering method on the piezoelectric layer. A phase electrode was formed, the temperature at this time was 25 to 250 (° C.), the pressure was 0.4 to 1.5 (Pa), the thickness was 30 to 100 (nm), the stress was 0.3 to 2.0 (GPa), In addition, a phase electrode having a specific resistance of 2.0 (x10 ^-7 Pa.m) or less is formed.

Description

METHOD FOR PRODUCING ACTUATOR DEVICE, ACTUATOR DEVICE, LIQUID-JET HEAD AND LIQUID-JET APPARATUS}

1 is an exploded perspective view showing a schematic configuration of a recording head according to Embodiment 1 of the present invention.

2 is a plan view and a sectional view of a recording head according to Embodiment 1 of the present invention.

3 is a cross-sectional view showing a manufacturing method of a recording head according to Embodiment 1 of the present invention.

4 is a cross-sectional view showing a manufacturing method of a recording head according to Embodiment 1 of the present invention.

Fig. 5 is a sectional view showing the method of manufacturing the recording head according to the first embodiment of the present invention.

6 is a cross-sectional view showing a manufacturing method of a recording head according to Embodiment 1 of the present invention.

7 is a hysteresis curve of PZT thin films according to Examples and Comparative Examples.

8 is a schematic diagram of a recording apparatus according to an embodiment of the present invention.

<Description of simple symbols for main parts of the drawing>

10: flow path forming substrate 12: pressure generating chamber

13: communication part 14: ink supply path

20: nozzle plate 21: nozzle opening

30 protective substrate 31 piezoelectric element holding portion

32: reservoir part

40: compliance substrate 60: lower electrode film

65: seed titanium layer 70: piezoelectric layer

80: upper electrode film 90: lead electrode

95: insulating film 100: reservoir

300: piezoelectric element

The present invention relates to a method for manufacturing an actuator device having a piezoelectric element composed of a lower electrode, a piezoelectric layer made of a piezoelectric material, and an upper electrode on a vibration plate, and an actuator device, and a liquid jet head and a liquid jet device using the actuator device. .

As a piezoelectric element used in an actuator device, a piezoelectric material having an electromechanical conversion function, for example, a piezoelectric layer made of crystallized piezoelectric ceramics or the like, is provided between two electrodes, a lower electrode and an upper electrode. Such an actuator device is generally called an actuator device of a flexural vibration mode, and is used, for example, mounted on a liquid jet head or the like. As a representative example of the liquid jet head, for example, a part of the pressure generating chamber communicating with the nozzle opening for discharging ink droplets is composed of a diaphragm, and the diaphragm is deformed by a piezoelectric element to pressurize the ink in the pressure generating chamber. And an ink-jet recording head for ejecting ink droplets from the nozzle opening. As the actuator device mounted on the inkjet recording head, for example, the entire piezoelectric material layer is formed on the entire surface of the diaphragm to form a uniform piezoelectric material layer by a film forming technique, and the piezoelectric material layer corresponds to the pressure generating chamber by the lithography method. Some piezoelectric elements are formed independently by dividing | segmenting into shape and for every pressure generation chamber (for example, refer patent document 1).

The actuator device having such a piezoelectric element has the advantage that the piezoelectric element can be manufactured at high density by a precise and simple method called a lithography method, the thickness of the piezoelectric element can be made thin, and high speed driving can be performed. . However, the piezoelectric element formed in this way has a problem that film peeling due to the film quality or film stress of each film constituting the piezoelectric element occurs. In particular, there is a problem that the upper electrode, which is the uppermost layer of the piezoelectric element, is easily peeled from the piezoelectric layer.

Moreover, in order to adjust the stress of the film | membrane which comprises a piezoelectric element, there exist some which provided the stress relaxation layer between piezoelectric layers (piezoelectric layer), for example (refer patent document 2). With such a structure, peeling of the film | membrane which comprises a piezoelectric element may be prevented to some extent. However, since the piezoelectric characteristics of the piezoelectric layer are deteriorated, there is a fear that a problem that the desired displacement cannot be obtained when the piezoelectric element is driven.

Of course, such a problem exists not only in the actuator device mounted in the liquid jet head such as an inkjet recording head, but also in the actuator device mounted in all other devices.

 [Patent Document 1] Japanese Patent Laid-Open No. 5-286131 (FIG. 3, paragraph [0013], etc.)

 [Patent Document 2] Japanese Patent Application Laid-Open No. 2004-128492 (claims, etc.)

SUMMARY OF THE INVENTION The present invention has been made in view of such a point, and it is possible to maintain the piezoelectric properties of the piezoelectric layer well and to prevent the peeling of the upper electrode, the actuator device, the liquid jet head and the liquid jet device. The task is to provide.

A first aspect of the present invention for solving the above problems has a step of forming a vibration plate on a substrate, and a step of forming a piezoelectric element consisting of a lower electrode, a piezoelectric layer and an upper electrode on the vibration plate, and further forms the piezoelectric element. In the step of forming the phase electrode on the piezoelectric layer by sputtering, the temperature is 25 to 250 (C), the pressure is 0.4 to 1.5 (Pa), and the thickness is 30 to 100 (nm). And a phase electrode having a stress of 0.3 to 2.0 (GPa) and a specific resistance of 2.0 (x10 ^-7 Pa.m) or less.

In the first aspect of the present invention, since the adhesion of the upper electrode to the piezoelectric layer is ensured, the film quality of the upper electrode can be improved while maintaining the piezoelectric characteristics of the piezoelectric layer. Therefore, the actuator device excellent in the displacement characteristic and durability can be realized.

A second aspect of the present invention is a method for manufacturing the actuator device according to the first aspect, wherein the power density at the time of forming the phase electrode is 3 to 30 (kW / m 2). In the second aspect according to the present invention, a phase electrode having a desired stress can be formed more reliably.

A third aspect of the present invention is a method for manufacturing the actuator device according to the first or second aspect, wherein iridium (Ir) is used as a material of the phase electrode.

In the third aspect according to the present invention, by using a predetermined material as the upper electrode, the film quality of the upper electrode is more surely improved.

A fourth aspect of the present invention is an actuator device, which is manufactured according to the manufacturing method of any one of the first to third aspects.

In the fourth aspect according to the present invention, an actuator device with remarkably improved displacement characteristics and durability is realized.

A fifth aspect of the present invention is a liquid ejection head, comprising the actuator device of the fourth aspect.

 In the fifth aspect according to the present invention, a liquid ejecting head is obtained in which good ejection characteristics are obtained and the durability is greatly improved.

A sixth aspect of the present invention is a liquid injection device comprising the liquid jet head of the fifth aspect.

In the sixth aspect according to the present invention, the ejection characteristics, the durability, and the like are improved, whereby a liquid ejecting apparatus having a large improvement in reliability can be realized.

EMBODIMENT OF THE INVENTION Below, this invention is demonstrated in detail based on embodiment.

(Embodiment 1)

1 is an exploded perspective view showing a schematic configuration of an inkjet recording head according to Embodiment 1 of the present invention, and FIG. 2 is a plan view of FIG. 1 and a cross-sectional view taken along line A-A 'thereof. As shown in the drawing, the flow path forming substrate 10 is made of a silicon single crystal substrate having a surface orientation 110 in this embodiment, and one surface is made of silicon dioxide previously formed by thermal oxidation. An elastic film 50 having a thickness of 0.5 to 2 µm is formed. In the flow path formation substrate 10, a plurality of pressure generating chambers 12 partitioned by a partition wall 11 are arranged in the width direction thereof. Moreover, the communication part 13 is formed in the area | region of the outer side of the pressure generation chamber 12 of the flow path formation board 10 in the longitudinal direction, and the communication part 13 and each pressure generation chamber 12 are each pressure generation chamber. It communicates with the ink supply path 14 provided in every 12. In addition, the communication part 13 communicates with the reservoir part of the protection board mentioned later, and comprises a part of the reservoir used as the common ink chamber of each pressure generation chamber 12. As shown in FIG. The ink supply passage 14 is formed to have a narrower width than the pressure generating chamber 12, and maintains a constant flow path resistance of ink flowing from the communicating portion 13 into the pressure generating chamber 12.

Moreover, the nozzle plate 20 in which the nozzle opening 21 which communicates in the vicinity of the edge part on the opposite side to the ink supply path 14 of each pressure generation chamber 12 at the opening surface side of the flow path formation board | substrate 10 is installed. ) Is adhered to each other by an adhesive agent, a heat welding film, or the like through a mask film 52 described later. The nozzle plate 20 is made of, for example, glass ceramics, silicon single crystal substrate, stainless steel, or the like.

On the other hand, an elastic film 50 having a thickness of, for example, about 1.0 μm, made of silicon dioxide, as described above, is formed on the side opposite to the opening surface of the flow path forming substrate 10, and on the elastic film 50, For example, an insulator film 55 made of zirconium oxide (ZrO ₂ ) or the like and having a thickness of, for example, about 0.4 μm is laminated. On the insulator film 55, the thickness is, for example, about 0.1 to 0.2 탆 lower electrode film 60, the thickness of the piezoelectric layer 70 is, for example, about 0.5 to 5 탆, and the thickness is, for example. A piezoelectric element 300 made of a phase electrode film 80 having a thickness of about 0.05 μm is formed. That is, in the present invention, the diaphragm has an oxide film, and the piezoelectric element 300 is formed on this oxide film. 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 lower electrode film 60 is used as the common electrode of the piezoelectric element 300 and the upper electrode film 80 is used as the individual electrode of the piezoelectric element 300. There is no problem. In addition, here, the piezoelectric element 300 and the diaphragm which a displacement generate | occur | produces by the drive of the said piezoelectric element 300 are combined, and it is called an actuator apparatus.

In addition, lead electrodes 90 made of, for example, gold (Au) and the like are connected to the upper electrode films 80 of the respective piezoelectric elements 300, and the respective piezoelectric elements are connected through the lead electrodes 90. Voltage 300 is selectively applied.

In the present embodiment, each layer of the piezoelectric element 300 and the pattern region of the lead electrode 90 are regions facing the connection portion 60a of the lower electrode film 60 and the connection portion 90a of the lead electrode 90. Except for the above, it is covered with an insulating film 95 made of an insulating material. That is, except for the connection portions 60a and 90a, the surfaces of the lower electrode film 60, the piezoelectric layer 70, the upper electrode film 80, and the lead electrode 90 are covered with the insulating film 95. For this reason, destruction by moisture (moisture) of the piezoelectric layer 70 is prevented. In addition, the material of the insulating film 95 is not particularly limited as long as it is an inorganic insulating material, and examples thereof include aluminum oxide (Al ₂ O ₃ ), tantalum pentoxide (Ta ₂ O ₅ ), and the like. ₂ O ₃ ) is preferably used.

A protective substrate 30 having a piezoelectric element holding part 31 for protecting the piezoelectric element 300 in a region facing the piezoelectric element 300 in the flow path forming substrate 10 on which the piezoelectric element 300 is formed. It is bonded by this adhesive agent. In addition, the piezoelectric element holding part 31 should just be able to ensure the space which does not impair the motion of the piezoelectric element 300, and even if the space is sealed, it does not need to be sealed. Moreover, the reservoir part 32 is provided in the area | region which opposes the communication part 13 in the protection board 30, and this reservoir part 32 is the communication part 13 of the flow path formation board 10 as mentioned above. ), Which constitutes a reservoir 100 which is a common ink chamber of each of the pressure generating chambers 12. In the region between the piezoelectric element holding portion 31 and the reservoir portion 32 of the protective substrate 30, a through hole 33 penetrating the protective substrate 30 in the thickness direction is provided. A part of the lower electrode film 60 and the leading end of the lead electrode 90 are exposed in 33, and the connection wirings extending from the driving IC although not shown in the lower electrode film 60 and the lead electrode 90 are shown. One end of is connected.

As the protective substrate 30, it is preferable to use a material substantially the same as the thermal expansion rate of the flow path formation substrate 10, for example, glass, ceramic material, and the like. In this embodiment, the silicon single crystal of the same material as the flow path formation substrate 10 is used. It formed using the board | substrate.

The compliance substrate 40 which becomes the sealing film 41 and the fixed plate 42 is bonded on the protective substrate 30. Here, the encapsulation film 41 is made of a material having low rigidity and flexibility (for example, a polyphenylene sulfide (PPS) film having a thickness of 6 μm). One side of the reservoir portion 32 is sealed. In addition, the fixing plate 42 is formed of a hard material such as metal (for example, stainless steel (SUS) having a thickness of 30 µm). Since the area | region which faces the reservoir 100 of this fixing plate 42 is the opening part 43 removed completely in the thickness direction, one side of the reservoir 100 is sealed only by the flexible sealing film 41 which is flexible. It is.

In the inkjet recording head of this embodiment as described above, ink is blown from an external ink supply means (not shown), filled with ink from the reservoir 100 to the nozzle opening 21, and then recorded from the drive IC. According to the signal, a voltage is applied between each of the lower electrode film 60 and the upper electrode film 80 corresponding to the pressure generating chamber 12, and the elastic film 50, the lower electrode film 60, and By bending the piezoelectric layer 70, the pressure in each pressure generating chamber 12 becomes high, and ink droplets are ejected from the nozzle opening 21. FIG.

Hereinafter, the manufacturing method of the inkjet recording head is demonstrated with reference to FIGS. 3 to 6 are cross-sectional views in the longitudinal direction of the pressure generating chamber 12. First, as shown in FIG. 3A, the silicon dioxide film 51 which thermally oxidizes the flow path forming substrate wafer 110, which is a silicon wafer, in a diffusion furnace at about 1100 ° C, and constitutes an elastic film 50 on its surface. ). In this embodiment, a silicon wafer having a relatively high rigidity with a film thickness of about 625 µm is used as the wafer-forming substrate wafer 110.

Next, as shown in FIG. 3B, an insulator film 55 made of zirconium oxide is formed on the elastic film 50 (silicon dioxide film 51). Specifically, after forming a zirconium (Zr) layer on the elastic film 50 (silicon dioxide film 51) by, for example, sputtering or the like, the zirconium layer is diffused, for example, 500 to 1200 ° C. By thermal oxidation in the furnace, an insulator film 55 made of zirconium oxide (ZrO ₂ ) is formed.

Next, as shown in Fig. 3C, a lower electrode film 60 made of platinum (Pt), iridium (Ir) or the like is formed on the entire surface of the insulator film 55, and then a predetermined shape is formed. Pattern with. For example, in this embodiment, the film | membrane which consists of iridium and the film | membrane which consists of platinum are laminated | stacked by the sputtering method, and the several laminated | multilayer film was patterned to predetermined shape, and it was set as the lower electrode film 60. FIG.

Next, as shown in FIG. 3D, titanium (Ti) is applied onto the lower electrode film 60 and the insulator film 55 by, for example, a sputtering method or the like, thereby depositing the seed titanium layer 65 having a predetermined thickness. Form. Next, on this seed titanium layer 65, a piezoelectric material, in this embodiment, a piezoelectric layer 70 made of lead zirconate titanate (PZT) is formed. In the present embodiment, a so-called sol obtained by dissolving and dispersing a metal organic substance in a catalyst is applied to dry, gelled, and fired at a high temperature to obtain a piezoelectric layer 70 made of a metal oxide. The piezoelectric layer 70 was formed using a so-called sol-gel method. In addition, the manufacturing method of the piezoelectric layer 70 is not limited to the sol-gel method, For example, you may use the metal-organic decomposition (MOD) method.

As an example of the formation procedure of the piezoelectric layer 70, first, as shown in FIG. 4A, the piezoelectric precursor film 71 which is a PZT precursor film is formed on the seed titanium layer 65. FIG. That is, a sol (solution) containing a metal organic compound is applied onto the wafer-forming substrate wafer 110. Next, the piezoelectric precursor film 71 is heated to a predetermined temperature and dried for a certain time, and the piezoelectric precursor film 71 is dried by evaporating the solvent of the sol. In addition, the piezoelectric precursor film 71 is degreased at a constant temperature in an air atmosphere. In addition, the organic component is to say degreasing of jolmak where, for example, is to escape to the _{NO 2, CO 2, H 2} O and the like.

The process of coating, drying, and degreasing is repeated a predetermined number of times, for example, twice, to form the piezoelectric precursor film 71 at a predetermined thickness as shown in Fig. 4B, and the piezoelectric precursor film 71 is formed. ) Is heat-treated in a diffusion furnace or the like to crystallize to form the piezoelectric film 72. That is, by firing the piezoelectric precursor film 71, crystals grow using the seed titanium layer 65 as a nucleus to form the piezoelectric film 72. In addition, it is preferable that the baking temperature is about 650-850 degreeC. For example, in this embodiment, the piezoelectric precursor film 71 was baked at about 700 degreeC for 30 minutes, and the piezoelectric film 72 was formed. In addition, the crystal of the piezoelectric film 72 formed under such conditions is first oriented to the (100) plane.

In addition, by repeating the above-described application, drying, degreasing and firing processes a plurality of times, as shown in Fig. 4C, for example, a piezoelectric layer 70 having a predetermined thickness composed of five layers of piezoelectric films 72 is formed. Form.

As the material of the piezoelectric layer 70, for example, a relaxer ferroelectric in which a metal such as niobium, nickel, magnesium, bismuth, or yttrium is added to a ferroelectric piezoelectric material such as lead zirconate titanate (PZT) or the like. You can also use The composition may be appropriately selected in consideration of the characteristics, uses, and the like of the piezoelectric element. For example, PbTiO ₃ (PT), PbZrO ₃ (PZ), Pb (Zr _x Ti _{l- x} ) O ₃ (PZT), Pb ( _{Mg l / 3 Nb 2/3} ) O 3 -PbTiO 3 (PMN-PT), Pb (Zn l / 3 Nb 2/3) O 3 -PbTiO 3 (PZN-PT), Pb (Ni l / 3 Nb 2 _{/ 3) O 3 -PbTiO 3 (} PNN-PT), Pb (In l / 2 Nb l / 2) O 3 -PbTiO 3 (PIN-PT), Pb (Sc l / 3 Ta 2/3) O 3 - _{PbTiO 3 (PST-PT),} Pb (Sc l / 3 Nb 2/3) O 3 -PbTiO 3 (PSN-PT), BiScO 3 -PbTiO 3 (BS- PT), BiYbO 3 -PbTiO 3 (BY-PT ), And the like.

After the piezoelectric layer 70 is formed in this manner, as shown in FIG. 5A, for example, an upper electrode film 80 made of iridium (Ir) is formed on the entire surface of the wafer-forming substrate 110. At this time, in the present invention, the upper electrode film 80 has a thickness of 30 to 100 nm, a stress of 0.3 to 2.0 GPa, and a specific resistance by sputtering, for example, DC or RF sputtering. It formed so that it might be 2.0 (x10 <^-7> Pa * m) or less. In this case, the stress in the tensile direction is represented by a positive value, and the stress in the compression direction is represented by a negative value.

In order to ensure that the stress and specific resistance of the upper electrode film 80 are as described above, the sputtering pressure when forming the upper electrode film 80 is set to 0.4 to 1.5 (Pa), and the upper electrode film 80 is formed. The temperature at that time, that is, the heating temperature of the flow path forming substrate wafer 110 is in the range of 25 ° C (room temperature) to 250 ° C. For this reason, by forming the upper electrode film 80 to a thickness of 30 to 100 (nm), the stress of the upper electrode film 80 can be set to a desired value, and the specific resistance can also be made to a desired value. In addition, the temperature at the time of forming the upper electrode film 80 is in the range of 25 ° C. (room temperature) to 250 ° C. to damage the piezoelectric layer 70 due to heat when forming the upper electrode film 80. The piezoelectric properties of the piezoelectric layer 70 can be maintained satisfactorily.

Moreover, although the power density at the time of forming an upper electrode film into a film by sputtering method is not specifically limited, It is preferable to set it as the range of 3-30 (kW / m <2>). For this reason, the upper electrode film 80 whose stress and non-resistance are the above values can be formed more reliably.

In addition, by forming the upper electrode film 80 under the above conditions, the specific resistance of the upper electrode film 80 can be set to 2.0 (x10 ^-7 Pa · m) or less, but the specific resistance of the upper electrode film 80 is reduced. Silver can also be adjusted by changing the gas pressure of argon (Ar) or the like introduced when forming the upper electrode film 80 by the sputtering method.

After the upper electrode film 80 is formed in this manner, as shown in FIG. 5B, the piezoelectric layer 70 and the upper electrode film 80 are patterned in regions facing the pressure generating chambers 12 to form a piezoelectric element ( 300). After the piezoelectric element 300 is formed, as illustrated in FIG. 5C, the piezoelectric element 300 is formed on the entire surface of the wafer-forming substrate wafer 110, and a metal layer 91 made of, for example, gold (Au) or the like is formed. Subsequently, the lead electrode 90 is formed by patterning the metal layer 91 for each piezoelectric element 300 through a mask pattern (not shown) made of, for example, a resist.

Next, as shown in FIG. 5D, an insulating film 95 made of, for example, aluminum oxide (Al ₂ O ₃ ) is formed. That is, the insulating film 95 is formed on the entire surface of the flow path forming substrate 10, and then the insulating film 95 is patterned by dry etching such as ion milling to connect the lower electrode film 60 to the connection portion ( The area | region which consists of the connection part 90a of 60a) and the lead electrode 90, etc. are exposed.

Next, as shown in FIG. 6A, the protective substrate wafer 130 made of a plurality of protective substrates 30 is bonded to the piezoelectric element 300 side of the flow path forming substrate wafer 110. Since the protective substrate wafer 130 has a thickness of, for example, about 400 μm, the rigidity of the flow path forming substrate wafer 110 is remarkably improved by joining the protective substrate wafer 130. .

Subsequently, as shown in FIG. 6B, the flow path forming substrate wafer 110 is polished to a certain thickness and then wet-etched again by hook nitric acid, whereby the flow path forming substrate wafer 110 is predetermined. Let thickness be. For example, in this embodiment, the flow path formation substrate wafer 110 was etched to have a thickness of about 70 µm. Subsequently, as shown in FIG. 6C, a mask film 52 made of, for example, silicon nitride (SiN) is newly formed on the flow path forming substrate wafer 110, and patterned into a predetermined shape. Then, by anisotropically etching the flow path forming substrate wafer 110 through the mask film 52, the pressure generating chamber 12 and the communication portion 13 are connected to the flow path forming substrate wafer 110 as shown in FIG. 6D. And an ink supply passage 14 and the like.

After that, unnecessary portions of the outer periphery of the flow path forming substrate wafer 110 and the protective substrate wafer 130 are removed by, for example, dicing or the like. The nozzle plate 20 on which the nozzle opening 21 is formed is bonded to the surface on the side opposite to the protective substrate wafer 130 of the flow path forming substrate wafer 110, and is also compliant with the protective substrate wafer 130. The inkjet recording head of this embodiment is formed by bonding the substrate 40 and dividing the wafer-forming substrate wafer 110 and the like into the one-chip sized channel forming substrate 10 and the like shown in FIG.

As described above, in the present invention, the upper electrode film 80 constituting the piezoelectric element 300 has a thickness of 30 to 100 nm, a stress of 0.3 to 2.0 GPa, and a resistivity of 2.0 (× 10). ^{It was} formed so as to be ^-7 Pa · m) or less. As a result, the adhesion between the upper electrode film 80 and the piezoelectric layer 70 is improved to prevent peeling of the upper electrode film 80, and the electrical characteristics of the piezoelectric layer 70 are not deteriorated. That is, the upper electrode film 80 is easily peeled off when the stress in the compressive direction is strong, and hardly peeled off when the stress in the tensile direction is strong, but the polarization characteristic of the piezoelectric layer 70 tends to be lowered. By forming the electrode film 80, the piezoelectric element 300 having both excellent electrical characteristics of the piezoelectric layer 70 and adhesion of the upper electrode film 80 can be obtained. The lower limit is not particularly limited as long as the specific resistance is 2.0 (× 10 ⁻⁷ Pa · m) or less, but preferably 1.59 (× 10 ⁻⁷ Pa · m) or more.

In addition, since the film quality of the upper electrode film 80 is improved and the surface becomes a smooth surface substantially free of irregularities, the insulating film 95 also has a uniform thickness on the upper electrode film 80. Is formed satisfactorily, and as a result, peeling of the insulating film 95 is also prevented. Therefore, an actuator device excellent in displacement characteristics and durability can be obtained, and an inkjet recording head capable of maintaining good print quality for long-term operation can be realized.

Here, the actuator device of Examples 1-8 and Comparative Examples 1-15 which produced the Ir film which is an upper electrode film on the film-forming conditions shown in following Table 1 was produced, The upper electrode in the actuator apparatus of each of these Examples and Comparative Examples was produced. The stress in the direction in which the film was deflected to the maximum was measured, and the displacement amount of the actuator device and the adhesion to the piezoelectric layer of the upper electrode film TE were evaluated. The results are shown in Table 1 below.

In addition, when the displacement amount of the actuator device is almost 210 (nm) or less, the ejection characteristics of the ink are affected in the structure of the liquid ejection head. For this reason, when the displacement amount of the actuator was 210 (nm) or more, it evaluated as "good", and when smaller than 210 (nm), it evaluated as "low" (defect). In addition, the adhesion between the upper electrode film TE and the piezoelectric layer is observed at the stage in which the actuator device is manufactured, and the space between the upper electrode film and the upper electrode film with the piezoelectric layer is observed. Rated by the presence or absence. That is, when the said peeling and space existed, it evaluated as "deterioration" (defect), and if not, it evaluated as "good".

TABLE 1

Ir deposition conditions Ir resistivity (× 10 ^-7 Ωm) Stress in maximum bending direction (GPa) Displacement TE adhesion Example 1 25 ℃, 0.4Pa, 30kW / ㎡ 2.0 1.997 Good Good Example 2 100 ℃, 0.4Pa, 30kW / ㎡ 2.0 1.828 Good Good Example 3 250 ℃, 0.4Pa, 30kW / ㎡ 1.8 1.435 Good Good Example 4 250 ° C, 0.4Pa, 3kW / ㎡ 1.6 0.396 Good Good Example 5 250 ° C, 0.4Pa, 7.5kW / ㎡ 1.7 0.911 Good Good Example 6 250 ℃, 0.4Pa, 15kW / ㎡ 1.7 1.349 Good Good Example 7 250 ℃, 0.8Pa, 30kW / ㎡ 1.8 1.504 Good Good Example 8 250 ℃, 1.5Pa, 30kW / ㎡ 1.8 1.483 Good Good Comparative Example 1 350 ℃, 0.4Pa, 3kW / ㎡ 1.3 -0.100 Lowering Good Comparative Example 2 350 ℃, 0.4Pa, 7.5kW / ㎡ 1.4 0.156 Lowering Good Comparative Example 3 350 ℃, 0.4Pa, 15kW / ㎡ 1.6 0.233 Lowering Good Comparative Example 4 350 ℃, 0.4Pa, 30kW / ㎡ 1.6 0.631 Lowering Good Comparative Example 5 350 ° C, .4Pa ,, 60kW / ㎡ 1.7 0.732 Lowering Good Comparative Example 6 250 ℃, 3.0Pa, 30kW / ㎡ 1.9 1.362 Good Lowering Comparative Example 7 25 ℃, 4.0Pa, 3kW / ㎡ 3.9 -0.105 Good Lowering Comparative Example 8 100 ℃, 4.0Pa, 3kW / ㎡ 2.8 -0.549 Good Lowering Comparative Example 9 150 ℃, 4.0Pa, 3kW / ㎡ 2.7 -0.526 Good Lowering Comparative Example 10 250 ℃, 4.0Pa, 3kW / ㎡ 1.3 -0.738 Good Lowering Comparative Example 11 350 ℃, 4.0Pa, 3kW / ㎡ 1.1 -0.208 Lowering Lowering Comparative Example 12 25 ℃, 4.0Pa, 30kW / ㎡ 2.1 2.232 Good Lowering Comparative Example 13 150 ℃, 4.0Pa, 30kW / ㎡ 1.9 1.689 Good Lowering Comparative Example 14 250 ℃, 4.0Pa, 30kW / ㎡ 1.8 1.277 Good Lowering Comparative Example 15 350 ℃, 4.0Pa, 30kW / ㎡ 1.6 0.662 Lowering Lowering

As shown in Table 1, in the actuator devices of Examples 1 to 8, both the displacement amount and the TE adhesion force were evaluated as "good", but in the actuator devices of Comparative Examples 1 to 15, at least one of the displacement amount and the TE adhesion force was "lower". It is evaluated. As is apparent from this result, according to the present invention, the adhesion between the upper electrode film 80 and the piezoelectric layer 70 can be improved to prevent peeling of the upper electrode film 80, and the piezoelectric body can be prevented. The electrical properties of layer 70 can also be maintained well.

In addition, the results of investigating the residual polarization (2Pr) of the PZT thin film which is the piezoelectric layer in the actuator device (actuator device of Example 4 and Comparative Example 2) selected arbitrarily from the actuators of the above Examples and Comparative Examples are shown in Table 2 below. Indicates. In addition, Table 2 below shows Ir film formation conditions, Ir stress, Ir resistivity, and displacement of the actuator device. 7, the hysteresis curve of the PZT thin film (piezoelectric layer) in the actuator apparatus of an Example and a comparative example is shown.

TABLE 2

Ir deposition conditions Ir stress (GPa) Ir resistivity (m 2Pr (μC / ㎠) of PZT membrane Displacement Example 250 ° C, 0.4Pa, 3kW / ㎡ 0.396 1.592 × 10 ^-7 30 Good (221 nm) Comparative example 350 ℃, 0.4Pa, 7.5kW / ㎡ 0.156 1.449 × 10 ^-7 7 Drop (200nm)

As shown in Table 2 above, in the actuator device of the example, both the residual polarization (2Pr) of the PZT thin film and the displacement amount of the actuator showed good values, but in the actuator device of the comparative example, these values were all lower than those of the actuator device of the example. . In addition, it can be seen from the hysteresis curve of the PZT thin film shown in FIG. 7 that the actuator device of the example has a larger polarization strength than the comparative example.

In addition, although the sputter | spatter pressure Pa was 0.4 (Pa) in the Example shown in the said Table 2, of course, a sputter | spatter pressure should just be 0.4-1.5 (Pa). Moreover, although temperature is 250 degreeC, what is necessary is just 25-250 degreeC. For this reason, the residual polarization 2Pr of a PZT thin film becomes a numerical value certainly higher than the said comparative example.

In addition, iridium (Ir) may be used as the material of the upper electrode film 80. The specific shape of the upper electrode film 80 is not limited to a single layer of iridium (Ir), but may be formed of an alloy layer containing iridium (Ir) as a main component. Alternatively, the upper electrode film 80 may be formed by laminating another layer on a surface on the side opposite to the surface of the alloy layer containing iridium (Ir) or an alloy layer containing iridium (Ir) as the main component.

(Other embodiment)

As mentioned above, although embodiment of this invention was described, this invention is not limited to embodiment mentioned above.

The inkjet recording heads of each of these embodiments constitute a part of the recording head unit including an ink flow passage communicating with an ink cartridge or the like, and are mounted on the inkjet recording apparatus. 8 is a schematic view showing an example of the inkjet recording apparatus. As shown in Fig. 8, the recording head units 1A and 1B having the inkjet recording heads are detachably provided with cartridges 2A and 2B constituting ink supply means, and the recording head units 1A and 1B are detached. The mounted carriage 3 is freely moved in the axial direction on the carriage shaft 5 attached to the apparatus main body 4. The recording head units 1A and 1B respectively discharge the black ink composition and the color ink composition, for example.

Then, the driving force of the drive motor 6 is transmitted to the carriage 3 via a plurality of gears and timing belts 7 not shown, so that the carriage 3 on which the recording head units 1A and 1B are mounted is provided. It moves along the carriage shaft 5. On the other hand, the apparatus main body 4 is provided with a platen 8 along the carriage shaft 5, and the recording sheet S, which is a recording medium such as paper fed by a paper feeding roller or the like, is platen ( 8) The stomach is supposed to be returned.

In addition, in Embodiment 1 mentioned above, although the inkjet recording head was mentioned and demonstrated as an example of a liquid jet head, this invention is wide and covers the whole liquid jet head, and of course applies also to the liquid jet head which injects liquid other than ink. can do. As other liquid jet heads, for example, various recording heads used for image recording apparatuses such as printers, color material jet heads used for the production of color filters such as liquid crystal displays, organic EL desk play FED (field emission display) The electrode material injection head used for electrode formation, etc., the bioorganic material injection head used for biochip manufacture, etc. are mentioned. Moreover, it goes without saying that the present invention can be applied not only to the actuator device used for the liquid jet head, but also to the actuator device mounted on all other devices such as a sensor.

According to the present invention, there is provided a method and method for manufacturing an actuator device having a piezoelectric element composed of a lower electrode, a piezoelectric layer made of a piezoelectric material, and an upper electrode on a vibration plate, and a liquid ejecting head and a liquid ejecting device using the actuator device. Can provide.

Claims (6)

Forming a diaphragm on the substrate, Forming a piezoelectric element consisting of a lower electrode, a piezoelectric layer, and an upper electrode on the vibrating plate, In the step of forming the piezoelectric element, the phase electrode is formed on the piezoelectric layer by sputtering, the temperature at this time is 25 to 250 (° C) and the pressure is 0.4 to 1.5 (Pa). A method of manufacturing an actuator device, wherein the phase electrode is formed with a thickness of 30 to 100 nm, a stress of 0.3 to 2.0 GPa, and a resistivity of 2.0 (x10 ^-7 Pa.m) or less. The method of claim 1, A method for manufacturing an actuator device, wherein the power density at the time of forming the phase electrode is set to 3 to 30 (kW / m 2). The method of claim 1, Iridium (Ir) was used as a material of the said phase electrode, The manufacturing method of the actuator apparatus characterized by the above-mentioned. And a piezoelectric element formed on the substrate, and a lower electrode, a piezoelectric layer, and an upper electrode formed on the vibration plate, And said phase electrode has a thickness of 30 to 100 nm, a stress of 0.3 to 2.0 GPa, and a resistivity of 2.0 (x10 ^-7 Pa.m) or less. A liquid jet head comprising the actuator device according to claim 4. A liquid ejecting apparatus, comprising the liquid ejecting head according to claim 5.

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