JP4516166B2 - Method for manufacturing ink jet recording head - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a ferroelectric element suitable for high-speed operation, and more particularly to a piezoelectric element suitable for high-frequency driving and a nonvolatile ferroelectric memory element suitable for high-frequency reading / writing.
[0002]
[Prior art]
Ferroelectric composite oxide crystalline materials, such as lead zirconate titanate, barium titanate, lithium niobate, etc., spontaneous polarization, high dielectric constant, electro-optic effect, piezoelectric effect, pyroelectric effect And so on, it has been applied to a wide range of device development. For example, as a piezoelectric element using the piezoelectricity, pyroelectricity is used for a non-volatile ferroelectric memory element such as a FRAM (Ferroelectric Random Access Memory) that reads / writes data using polarization characteristics. It is used in various fields such as an infrared linear array sensor and a waveguide type optical modulator utilizing its electro-optic effect. Since the ferroelectric element using the ferroelectric material has various functions, it is also called a functional element.
[0003]
For example, ferroelectric materials for piezoelectric elements generally contain lead, zirconium, titanium, etc., the A site is composed of divalent ions such as lead, and the B site is composed of tetravalent ions such as Zr, Ti. A PZT material having an ABO ₃ type perovskite type crystal structure is used. Specifically, Pb (Ni _1/2 W _1/2 ) O ₃ , Pb (Co _1/3 Nb _2/3 ) O ₃ , Pb (Ni _1/3 Nb) having an average tetravalent B site. _2/3 ) A solid solution of a complex perovskite compound such as O ₃ and PZT is known.
[0004]
[Problems to be solved by the invention]
By the way, selection of such a ferroelectric material is performed by searching for a composition having a large dielectric displacement, an electromechanical coupling coefficient, a piezoelectric strain constant, and a mechanical displacement induced by an electric field. The present inventor considered the influence of the crystal structure of the ferroelectric material on the piezoelectric characteristics, and in Japanese Patent Laid-Open No. 10-81016, the rhombohedral whose preferred orientation direction is the (111) plane orientation or the (100) plane orientation. It was proposed that the crystalline PZT piezoelectric material exhibits good piezoelectric properties.
[0005]
However, in general, in the PZT-based material, the dielectric constant, electromechanical coupling coefficient, piezoelectric strain constant, and electric field-induced mechanical displacement show the maximum values because of rhombohedral and tetragonal ( It has been found that a plurality of crystal systems such as tetragonal (morphotropic phase boundary: hereinafter referred to as MPB) are mixed, or pseudo cubic (psudocubic). For example, when a piezoelectric element is formed using a composition in the vicinity of MPB in a crystal structure with a plane orientation (111) preferential orientation, there is a case where a domain is rotated by voltage application when the element is driven by the orientation orientation of crystal grains. Arise.
[0006]
When such domain rotation is used as an actuator, it takes time for the domain rotation to return, which causes a disadvantage that high-speed driving cannot be performed. In particular, when a piezoelectric element is used as an ink discharge drive source for an ink jet recording head, there arises a disadvantage that high displacement characteristics cannot be obtained at a drive frequency of about 14 kHz to 28 kHz.
[0007]
In addition to the above crystal structure, the present inventor has a crystal structure in which the crystal system is tetragonal and is preferentially oriented to (001), a crystal structure in which the crystal system is tetragonal and is preferentially oriented to (111), Experiments were also conducted on each of the crystal structures in which the crystal system is rhombohedral and preferentially oriented to (111). When the composition near the MPB is used in any of these crystal structures, domain rotation occurs, resulting in high-speed driving. Turned out to be unsuitable.
[0008]
PZT-based materials are also applied to nonvolatile ferroelectric memory elements by utilizing their polarization characteristics, but the above-described problems also occur in high-frequency reading / writing of the memory elements.
[0009]
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method for manufacturing an ink jet recording head using a ferroelectric element capable of high-speed operation without rotation of a domain as an ink discharge drive source in order to solve the above-described problems. And
[0010]
An ink jet recording head manufacturing method according to the present invention includes a pressurizing chamber whose internal volume changes due to mechanical displacement of a piezoelectric element that functions as an ink ejection drive source, and ejects ink droplets in communication with the pressurizing chamber. In a method of manufacturing an ink jet recording head having an ejection port, Ir and Ti 2 are formed on a substrate on which the pressurizing chamber is processed using a single crystal substrate having a (110) plane orientation through a diaphragm film. A step of forming a lower electrode of the piezoelectric element made of a layer, a step of forming a layer made of Ti having a thickness of 30 nm on the lower electrode, and a composition of Pb (Zr _0.56 Ti _0.44 on the layer made of Ti. And a step of epitaxially growing a piezoelectric layer of the piezoelectric element having a perovskite crystal structure in the vicinity of MPB (crystal phase boundary) and a preferential orientation of (110) with O ₃ .
[0011]
By adopting such a configuration of the ferroelectric element, it is possible to drive the ferroelectric element without rotating the domain. For example, when the ferroelectric film is a tetragonal crystal, if the preferred orientation plane of the ferroelectric element is selected as the (110) plane, two of the six polarization axes are parallel to the (110) plane. The two polarization axes are not displaced by the voltage applied to the ferroelectric element. Also, two of the remaining four polarization axes form an angle of 45 ° upward with respect to the (110) plane, and two form an angle of 45 ° downward with respect to the (110) plane. Therefore, by reversing the latter two polarization axes by 180 ° by polarization processing, both are symmetric with respect to the normal line of the (110) plane, so that the rotation of the domain occurs even when a voltage is applied to the ferroelectric element. Not accompanied.
[0012]
Similarly, when the ferroelectric film is rhombohedral, when the preferential orientation plane of the ferroelectric element is selected as the (110) plane, four of the eight polarization axes are parallel to the (110) plane. Thus, the two polarization axes are not displaced by the voltage applied to the ferroelectric element. Of the remaining four polarization axes, two form an angle of approximately 35 ° upward with respect to the (110) plane, and two form an angle of approximately 35 ° downward with respect to the (110) plane. Therefore, by inverting the latter two polarization axes by 180 ° by polarization processing, both are symmetric with respect to the normal line of the (110) plane, so that the domain can be applied even if a voltage is applied to the ferroelectric element. Without rotation. Therefore, it is possible to provide a ferroelectric element that can be driven at a high speed by the above configuration.
[0013]
The ferroelectric film is preferably a thin film epitaxially grown in the (110) plane orientation. The degree of orientation in the (110) plane orientation can be increased by epitaxial growth.
[0014]
As the ferroelectric film, for example, a composite oxide crystalline material having an ABO ₃ type perovskite crystal structure is preferable. In this case, an additive may be included such as (A ₁ A ₂ ) BO ₃ or a multicomponent system such as A (B ₁ B ₂ ) O ₃ may be used. As a specific example of the ferroelectric film, lead zirconate titanate is suitable.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present embodiment will be described with reference to the drawings.
[0021]
FIG. 1 is a configuration diagram of an ink jet printer. The ink jet printer mainly includes an ink jet recording head 100, a main body 102, a tray 103, and a head driving mechanism 106. The ink jet recording head 100 includes a total of four ink cartridges 101 of yellow, magenta, cyan, and black, and is configured to be capable of full color printing. In addition, this ink jet printer includes a dedicated controller board and the like, and controls ink ejection timing of the ink jet recording head 100 and scanning of the head driving mechanism 106 to perform highly accurate ink dot control, halftone processing, and the like. Is realized. In addition, the main body 102 includes a tray 103 on the back surface and an auto seed feeder (automatic continuous paper feeding mechanism) 105 inside the main body 102 to automatically feed the recording paper 107 and eject the recording paper 107 from the front discharge port 104. Make paper. As the recording paper 107, plain paper, exclusive paper, recommended OHP sheet, glossy paper, glossy film, level sheet, government postcard, and the like can be used.
[0022]
FIG. 2 is an exploded perspective view of the ink jet recording head. Here, a type in which a common ink flow path is provided in the pressurizing chamber substrate is shown. As shown in the figure, the ink jet recording head includes a pressurizing chamber substrate 1, a nozzle plate 2, and a base 3. The pressurizing chamber substrate 1 is separated into each after a silicon single crystal substrate having a (110) plane orientation is etched. The pressurizing chamber substrate 1 is provided with a plurality of strip-shaped pressurizing chambers 10 and includes a common flow path 12 for supplying ink to all the pressurizing chambers (cavities) 10. The pressurizing chambers 10 are separated by side walls 11. A piezoelectric element is attached to the base 3 side of the pressurizing chamber substrate 1 as an ink discharge drive source. The wiring from each piezoelectric element is converged on the wiring board 4 which is a flexible cable, and is controlled by the print engine unit.
[0023]
The nozzle plate 2 is bonded to the pressurizing chamber substrate 1. A nozzle (ejection port) 21 for ejecting ink droplets is formed at a position corresponding to the pressurizing chamber 10 in the nozzle plate 2. The nozzles 21 are arranged in a line in a direction substantially parallel to the main scanning direction of the ink jet recording head at the time of printing, and the pitch between the nozzles is appropriately set according to the printing accuracy. For example, if a resolution of 1440 dpi × 720 dpi is set, the nozzle diameter becomes extremely fine, and therefore high-definition printing is possible with ultra-fine ink dots. The number of nozzles for each color is determined according to the color printing accuracy. For example, 32 nozzles for black and 32 nozzles for each color are set. The base 3 is made of plastic or the like and serves as a mounting base for the pressurizing chamber substrate 1.
[0024]
FIG. 3F is a cross-sectional view of the main part of the ink jet recording head. A pressurizing chamber 10 is formed on the pressurizing chamber substrate 1 by etching. An underlayer 5 that functions as a diaphragm film is formed on the upper surface of the pressurizing chamber 10, and a piezoelectric element 9 is formed on the underlayer 5. The piezoelectric element 9 is an example of a ferroelectric element of the present invention. The mechanical displacement of the element changes the internal volume in the pressurizing chamber 10 and ejects ink filled in the pressurizing chamber 10 from the nozzle 21. As shown in FIG. 2C, the piezoelectric element 9 includes a lower electrode 6, a piezoelectric film 7, and an upper electrode 8. The piezoelectric element 9 is also called a piezoelectric actuator, a microactuator, an electromechanical conversion element, or a minute displacement control element.
[0025]
The piezoelectric film 7 is one which is formed from _{PZT (PbZr X Ti 1-X} O 3) based material MPB vicinity preferential orientation treatment is made on (110) plane orientation. When a PZT film is adopted as the piezoelectric film 7, a film mainly composed of a two-component system or a film composed mainly of a three-component system obtained by adding a third component to the two-component system is suitable. Preferred specific examples of the binary PZT include
Pb (Zr _x Ti _1-x ) O ₃ + YPbO
Those having a composition represented by the chemical formula: Here, X and Y are
0.40 ≦ X ≦ 0.60, 0 ≦ Y ≦ 0.30
Those having the following relationship are preferable.
[0026]
Further, preferred specific examples of the ternary PZT include those having a composition represented by the following chemical formula in which, for example, a third component is added to the two-component PZT.
[0027]
_{PbTi a Zr b (A g B} h) c O 3 + ePbO + (fMgO) n
Here, A is selected from a divalent metal selected from the group consisting of Mg, Co, Zn, Cd, Mn and Ni or a group consisting of Sb, Y, Fe, Sc, Yb, Lu, In and Cr. Represents a trivalent metal. B represents a pentavalent metal selected from the group consisting of Nb, Ta and Sb, or a hexavalent metal selected from the group consisting of W and Te. Also,
a + b + c = 1,
0.35 ≦ a ≦ 0.55, 0.25 ≦ b ≦ 0.55
0.1 ≦ c ≦ 0.40, 0 ≦ e ≦ 0.30, 0 ≦ f ≦ 0.15
g = f = 0.5, n = 0
Where A is a trivalent metal, B is not a hexavalent metal, A is a divalent metal, and B is a pentavalent metal, g is 1/3 And h is 2/3. Further, n represents 1 only when A is Mg and B is Nb.
[0028]
More preferable specific examples of the ternary system include lead magnesium niobate, that is, A is Mg, B is Nb, g is 1/3, and h is 2/3.
[0029]
Further, in any of these two-component PZT and three-component PZT, in order to improve the piezoelectric characteristics, a small amount of Ba, Sr, La, Nd, Nb, Ta, Sb, Bi, W, Mo and Ca etc. may be added. In particular, in a three-component system, addition of 0.1 mol% or less of Sr and Ba is more preferable for improving the piezoelectric characteristics. Further, in the case of a ternary system, addition of 0.10 mol% or less of Mn and Ni is preferable because the sinterability is improved.
[0030]
Other specific examples of the piezoelectric film 7 include, for example, a solid solution of Pb (Zn, Nb) O ₃ and PbTiO ₃ (PMN-PT), a solid solution of Pb (Mg, Nb) O ₃ and PbTiO ₃ (PZN-PT), Examples thereof include barium titanate (BaTiO ₃ ) and strontium barium titanate (Sr _X Ba _1-X TiO ₃ ).
[0031]
Next, the manufacturing process of the piezoelectric element will be described together with the manufacturing process of the ink jet recording head with reference to FIGS.
Example 1
As shown in FIG. 3A, the rear layer (CeO ₂ ) is formed as an underlayer 5 on the pressurizing chamber substrate 1 made of a silicon single crystal substrate having a surface orientation (110) having a diameter of 100 mm and a thickness of 220 μm. A film was formed by epitaxial growth to a thickness of 0.5 μm by vapor deposition. Subsequently, platinum serving as the lower electrode 6 was epitaxially grown on the underlayer 2 to form a film having a thickness of about 100 nm, and then the organometallic raw material constituting the ferroelectric material was vaporized as shown in FIG. While appropriately adjusting the supply amounts of the source gas, the oxygen-containing gas, the carrier gas, etc., the piezoelectric film 7 was epitaxially grown by the CVD method to a thickness of about 1 μm.
[0032]
In general, in the case of bulk PZT, as a result of crystal phase identification by X-ray diffraction measurement for a crystal system near room temperature, the constituent element ratio of the B site in the perovskite structure, that is, the molar ratio of Zr / Ti is 0/1 or more and 0. When it is in the range of less than 53 / 0.47, it constitutes a tetragonal system, and when it is in the range of more than 0.53 / 0.47 and not more than 0.90 / 0.10, it constitutes a rhombohedral system. It has been found crystallographically that a tetragonal / rhombohedral crystal phase boundary, that is, MPB exists when the molar ratio of Zr / Ti is around 0.53 / 0.47. Therefore, in this example, the Zr / Ti molar ratio was 0.56 / 0.44, and the piezoelectric film 7 had a crystal structure near the MPB. Since the underlayer 5 and the lower electrode 6 are preferentially oriented in the (110) plane orientation, the piezoelectric film 7 epitaxially grown on the lower electrode 6 is also preferentially oriented in the (110) plane orientation.
[0033]
Further, as shown in FIG. 3C, platinum was deposited on the piezoelectric film 7 as the upper electrode 8 to a thickness of 100 nm by DC sputtering. Through the above steps, the piezoelectric element 9 including the upper electrode 8, the piezoelectric film 7, and the lower electrode 6 is obtained.
[0034]
When manufacturing an ink jet recording head using the piezoelectric element 9 as an ink discharge drive source, the following manufacturing process is further executed.
[0035]
A resist is spin-coated on the upper electrode 8, and exposure and development are performed and patterned in accordance with the position where the pressurizing chamber is to be formed. Using the remaining resist as a mask, the upper electrode 8, the piezoelectric film 7 and the lower electrode 6 were etched to separate the piezoelectric element 9 corresponding to the position where the pressurizing chamber was to be formed ((D) in the figure). The underlayer 5 functions as a diaphragm for pressurizing the pressurizing chamber. Subsequently, an etching mask is applied in accordance with the position where the pressurizing chamber is to be formed, and the pressurizing chamber substrate 1 is moved to a predetermined depth by dry etching using an active gas such as parallel plate type reactive ion etching. Etching was performed to form the pressurizing chamber 10 ((E) in the figure). The portion that remains without being etched becomes the side wall 11. In addition to dry etching, the pressure chamber substrate 1 can be anisotropically wet etched using, for example, a 10% potassium hydroxide aqueous solution kept at 80 ° C. In this case, a high-density array of the pressure chambers 10 can be easily formed by anisotropic wet etching.
[0036]
Finally, as shown in FIG. 5F, the nozzle plate 2 was joined to the pressurizing chamber substrate 1 using a resin or the like. The nozzle 21 can be formed by opening at a predetermined position of the nozzle plate 2 using a lithography method, laser processing, FIB processing, electric discharge processing, or the like. When the nozzle plate 2 is bonded to the pressurizing chamber substrate 1, the nozzles 21 are aligned so as to be arranged corresponding to the respective spaces of the pressurizing chamber 10. When the pressurizing chamber substrate 1 to which the nozzle plate 2 is bonded is attached to the base 3, an ink jet recording head is completed.
[0037]
According to the present embodiment, the piezoelectric film 7 is strongly oriented in the (110) plane orientation by epitaxial growth and has a crystal structure in the vicinity of the MPB. Therefore, when the piezoelectric element 9 is used as an actuator, It can be driven without rotation. Therefore, the piezoelectric element 9 suitable for high-speed driving can be manufactured.
[0038]
In the above example, ceria is formed as the underlayer 5, but ceria / ceria zirconia (CeO ₂ / CeZrO ₂ ) may be formed instead. In addition, a (110) plane silicon single crystal substrate was used as the pressurizing chamber substrate 1, but in addition to this, a (110) plane single crystal strontium titanate substrate (SrTiO ₃ : STO) and a (110) plane single crystal were used. A magnesium oxide substrate (MgO) may be used.
[0039]
Further, an arbitrary diaphragm film (for example, an epitaxially grown insulating film) may be interposed between the single crystal substrate and the lower electrode. The lower electrode is not particularly limited as long as it is a conductive material that can be epitaxially grown. In addition to platinum, a single layer made of iridium, an iridium layer / platinum layer, a platinum layer / iridium layer, an iridium layer / platinum layer / iridium A layered structure of layers may be used.
(Example 2)
As shown in FIG. 4A, a silicon dioxide film having a thickness of 1 μm is formed on a pressurized chamber substrate 1 made of a silicon single crystal substrate by thermal oxidation, and zirconium is used as a target and oxygen gas is introduced. A zirconium oxide film (ZrO ₂ ) was formed to a thickness of about 400 nm by reactive sputtering. The diaphragm film 51 is composed of the silicon dioxide film and the zirconium oxide film.
[0040]
Subsequently, a lower electrode 52 was formed on the diaphragm film 51 ((B) in the same figure). The lower electrode 52 has a laminated structure of a plurality of thin films such as iridium, titanium, platinum, etc., and its configuration is determined as appropriate in order to adjust the {110} preferential orientation degree of the piezoelectric film 54 to be formed in the next process. Is done. Further, a titanium layer 53 serving as a PZT seed layer was formed on the lower electrode 52 (FIG. (C)), and a piezoelectric film 54 was formed by a sol-gel method (FIG. (D)).
[0041]
In this embodiment, the composition of the piezoelectric film 54 is Pb (Zr _0.56 Ti _0.44 ) O ₃ , and a two-component PZT in which the molar mixing ratio of lead zirconate and lead titanate is 56:44. . The crystal of the piezoelectric film 54 is in the vicinity of the MPB. In order to form the piezoelectric film 54, a hydrated complex of metal component hydroxide constituting the PZT, that is, a sol was prepared. In order to prepare this sol, 2-n-butoxyethanol was used as a main solvent, and titanium tetraisopropoxide and tetra-n-propoxyzirconium were mixed therein and stirred at room temperature for 20 minutes. Next, diethanolamine was added, and the mixture was further stirred at room temperature for 20 minutes. Further, lead acetate was added and heated to 80 ° C. The mixture was stirred for 20 minutes in the heated state, and then naturally cooled to room temperature.
[0042]
The sol thus obtained was spin-coated for coating on the titanium layer 53. At this time, in order to make the film thickness uniform, spin coating was first performed at 500 rpm for 30 seconds, then at 1500 rpm for 30 seconds, and finally at 500 rpm for 10 seconds. In this step, each metal atom constituting PZT is dispersed as an organometallic complex. The sol was applied on the titanium layer 53, dried at 180 ° C. for 30 minutes, and degreased in air at 330 ° C. for 10 minutes using a hot plate. The steps from spin coating to degreasing were repeated twice, and thereafter, a crystallization heat treatment was performed in an annular atmosphere at 700 ° C. for 30 minutes. This process was further repeated 7 times to form a 1.6 μm-thick piezoelectric film 54 having a total of 14 layers.
[0043]
At this time, the {110} preferential orientation degree of the piezoelectric film 54 can be adjusted by appropriately adjusting the thickness of the titanium layer 53 and the configuration of the lower electrode 52. For example, when the thickness of the titanium layer 53 is set to 5 nm to 15 nm and the lower electrode 52 is Ir (film thickness 20 nm) / Pt (film thickness 60 nm) / Ir (film thickness 20 nm) / Ti (film thickness 20 nm), The {110} preferential orientation degree of the piezoelectric film 54 is about 30%, the film thickness of the titanium layer 53 is set to 30 nm, and the configuration of the lower electrode 52 is Ir (film thickness 200 nm to 300 nm) / Ti (film thickness 20 nm). ), The {110} preferred orientation degree of the piezoelectric film 54 was confirmed to be about 60%.
The orientation degree is, for example, when the reflection intensity of the plane orientation {XYZ} plane of the piezoelectric film is expressed by I (XYZ) by the wide angle XRD method.
I (XYZ) / {I (100) + I (110) + I (111)}
It shall be expressed as
[0044]
Finally, platinum was deposited on the piezoelectric film 54 by a sputtering method to form the upper electrode 55 ((E) in the figure). Through the above steps, a piezoelectric element 56 including the upper electrode 55, the piezoelectric film 54, the titanium layer 53, and the lower electrode 52 is obtained. In the case of manufacturing an ink jet recording head using the piezoelectric element 56 as an ink discharge drive source, a desired processing can be performed according to the steps shown in FIGS. 3D to 3F described in the first embodiment. Good.
[0045]
FIG. 5 shows the piezoelectric constant d ₃₁ when the {110} preferential orientation degree of the piezoelectric film 54 is changed. As shown in the figure, it can be confirmed that the piezoelectric property improves as the {110} priority orientation degree increases. The higher the {110} preferential orientation degree of the piezoelectric film 54, the less the domain rotation occurs when the piezoelectric element 56 is used as an actuator, so that an ink jet recording head suitable for high frequency driving can be provided. .
Other Embodiments The ferroelectric element of the present invention can be used as a charge storage capacitor of a nonvolatile ferroelectric memory element in addition to the piezoelectric element described above. Since the nonvolatile ferroelectric memory element reads / writes information using inversion of the polarization of the ferroelectric film, it has a crystal structure near the MPB and has a (110) preferential orientation PZT type ferroelectric A nonvolatile ferroelectric memory element suitable for high-frequency reading / writing can be provided by using a thin body film as a capacitor insulating film of a storage capacitor. Further, if such a ferroelectric film is used, the amount of remanent polarization can be increased more effectively than before, so that the size of the memory cell can be reduced and the degree of integration of the nonvolatile ferroelectric memory element can be increased. it can.
[0046]
In addition to the above, the ferroelectric element of the present invention includes a filter, a delay line, a lead selector, a tuning fork oscillator, a tuning fork clock, a transceiver, a piezoelectric pickup, a piezoelectric earphone, a piezoelectric microphone, a SAW filter, an RF modulator, a resonator, Can be applied to delay elements, multi-strip couplers, piezoelectric accelerometers, piezoelectric speakers, etc.
According to the present invention, it is possible to provide a ferroelectric element capable of operating at high speed without causing domain rotation. In particular, by using the ferroelectric element of the present invention as an ink ejection drive source for an ink jet recording head, an ink jet recording head excellent in high frequency characteristics can be provided.
[0047]
In addition, according to the present invention, a high-frequency read / write nonvolatile ferroelectric memory element can be provided.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of an ink jet printer.
FIG. 2 is an exploded perspective view of an ink jet recording head.
FIG. 3 is a cross-sectional view of an ink jet recording head manufacturing process.
FIG. 4 is a cross-sectional view of a manufacturing process of a piezoelectric element.
FIG. 5 is a graph of the piezoelectric constant d ₃₁ with respect to the {110} preferred orientation degree of the piezoelectric film.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Pressurization chamber board | substrate, 2 ... Nozzle plate, 3 ... Base | substrate, 4 ... Wiring board, 5 ... Underlayer, 6 ... Lower electrode, 7 ... Piezoelectric film, 8 ... Upper electrode, 9 ... Piezoelectric element, 10 ... Pressurizing chamber, 11 ... sidewall, 12 ... common flow path, 21 ... nozzle, 51 ... diaphragm film, 52 ... lower electrode, 53 ... titanium layer, 54 ... piezoelectric film, 55 ... upper electrode, 56 ... piezoelectric element DESCRIPTION OF SYMBOLS 100 ... Inkjet recording head 101 ... Ink cartridge 102 ... Main body 103 ... Tray 104 ... Discharge port 105 ... Auto sheet feeder 106 ... Head drive mechanism 107 ... Recording paper

Claims (2)

Manufacture of an ink jet recording head having a pressure chamber whose internal volume changes due to mechanical displacement of a piezoelectric element that functions as an ink discharge drive source, and a discharge port that communicates with the pressure chamber and discharges ink droplets In the method
Forming a lower electrode of the piezoelectric element composed of two layers of Ir and Ti on a substrate on which the pressurizing chamber is processed using a (110) plane single crystal substrate; ,
Forming a layer of Ti having a thickness of 30 nm on the lower electrode;
The composition on the layer is _{Pb (Zr 0.56 Ti 0.44) O} 3 made of the Ti, MPB perovskite crystal structure (crystalline phase boundary) and near (110) preferentially oriented epitaxial growth of the piezoelectric layer of the piezoelectric element with the And an ink jet recording head manufacturing method.   2. The method of manufacturing an ink jet recording head according to claim 1, wherein the lower electrode has a thickness of Ir of 200 to 300 nm and Ti of 20 nm.

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