JP2019014229A - Piezoelectric device, liquid jet head and liquid jet device - Google Patents

Abstract

A piezoelectric device, a liquid ejecting head, and a liquid ejecting apparatus that suppress the destruction of a film around a liquid supply port without hindering displacement of a piezoelectric element.
A piezoelectric device used in a liquid ejecting head for ejecting liquid from a nozzle, wherein individual liquid chambers are connected to the nozzle, and liquids are connected to the individual liquid chambers. A flow path forming substrate 10 in which a supply chamber 13 is formed, and a diaphragm 50 formed at a position corresponding to the individual liquid chambers 12, 14, 15 of the flow path forming substrate 10 and the liquid supply chamber 13. A plurality of liquid supply ports 16 formed in the liquid supply chamber 13, a first electrode 60, a piezoelectric layer 70, and a second electrode 80, and the individual liquid chambers 12, 14 of the diaphragm 50, 15 and the piezoelectric element 300 formed at a position corresponding to 15, the liquid supply port 16 is provided through the diaphragm 50, and the diaphragm 50 contains zirconium oxide.
[Selection] Figure 4

Description

  The present invention relates to a piezoelectric device having a piezoelectric element, a liquid ejecting head having a piezoelectric device, and a liquid ejecting apparatus including the liquid ejecting head.

  As a piezoelectric device used in an ink jet recording head which is a typical example of a liquid ejecting head, a flow path forming substrate provided with an individual flow path communicating with a nozzle and a liquid supply chamber communicating with the individual flow path, And a piezoelectric element provided on one side of the flow path forming substrate via a vibration plate.

  An ink jet recording head having such a piezoelectric device discloses a configuration in which a diaphragm is formed into a filter by providing the diaphragm with a plurality of liquid supply ports communicating with a liquid supply chamber (for example, Patent Documents). 1).

JP2013-993A

  However, when the liquid supply port is formed in the vibration plate, there is a problem that the ink supply pressure is applied to the vibration plate and thus the liquid supply port is easily broken.

  For this reason, in patent document 1, the internal stress of a diaphragm is adjusted by forming the diaphragm which forms a liquid supply port by laminating | stacking many layers, and the destruction of a diaphragm is suppressed. However, since a large number of layers are stacked and the diaphragm is thickened, there is a problem that the deformation of the piezoelectric element is hindered and the displacement characteristics are deteriorated.

  Such a problem exists not only in an ink jet recording head but also in a piezoelectric device used in a liquid ejecting head that ejects liquid other than ink.

  In view of such circumstances, it is an object of the present invention to provide a piezoelectric device, a liquid ejecting head, and a liquid ejecting apparatus that suppress the destruction of a film around a liquid supply port without inhibiting displacement of the piezoelectric element. .

  An aspect of the present invention that solves the above problem is a piezoelectric device used in a liquid ejecting head that ejects liquid from a nozzle, and includes an individual liquid chamber that communicates with the nozzle, a liquid supply chamber that communicates with the individual liquid chamber, , A flow path forming substrate, a diaphragm formed at a position corresponding to the individual liquid chamber and the liquid supply chamber of the flow path forming substrate, and a plurality of liquids formed in the liquid supply chamber A supply port; and a piezoelectric element that includes a first electrode, a piezoelectric layer, and a second electrode, and is formed at a position corresponding to the individual liquid chamber of the diaphragm, and the liquid supply port includes The piezoelectric device is provided to penetrate through the diaphragm, and the diaphragm includes zirconium oxide.

  According to another aspect of the invention, there is provided a liquid ejecting head including the piezoelectric device according to the above aspect.

  According to another aspect of the invention, there is provided a liquid ejecting apparatus including the liquid ejecting head according to the above aspect.

FIG. 3 is an exploded perspective view of the recording head. FIG. 2 is a plan view of a recording head. FIG. 3 is a cross-sectional view of a recording head. FIG. 3 is an enlarged cross-sectional view of a main part of the recording head. 1 is a diagram illustrating a schematic configuration of a recording apparatus.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the following description shows one embodiment of the present invention, and can be arbitrarily changed within the scope of the present invention. In the drawings, the same reference numerals denote the same members, and descriptions thereof are omitted as appropriate. In each figure, X, Y, and Z represent three spatial axes that are orthogonal to each other. In the present specification, directions along these axes will be described as a first direction X, a second direction Y, and a third direction Z.

(Embodiment)
FIG. 1 is an exploded perspective view of an ink jet recording head which is an example of a liquid jet head according to an embodiment of the present invention, FIG. 2 is a plan view of the ink jet recording head, and FIG. FIG. 4 is a cross-sectional view taken along line AA ′, and FIG. 4 is an enlarged view of a main part of FIG. 3.

As shown in the figure, the flow path forming substrate 10 constituting the ink jet recording head 1 (hereinafter also simply referred to as the recording head 1) is made of a metal such as stainless steel or Ni, a ceramic typified by ZrO ₂ or Al ₂ O _3. Materials, glass ceramic materials, oxides such as SiO ₂ , MgO, and LaAlO ₃ can be used. In the present embodiment, the flow path forming substrate 10 is made of a silicon single crystal substrate.

  The flow path forming substrate 10 is provided with a plurality of nozzles 21 in which pressure generating chambers 12 partitioned by a plurality of partition walls 11 discharge ink by performing anisotropic etching from one surface side. They are arranged along the direction X. Further, in the flow path forming substrate 10, an ink supply path 14 and a communication path 15 are partitioned by a partition wall 11 at one end side of the pressure generating chamber 12 in the second direction Y. That is, in the present embodiment, the flow path forming substrate 10 is provided with the pressure generation chamber 12, the ink supply path 14, and the communication path 15 as individual flow paths communicating with the nozzles 21.

  In addition, a communication portion 13 serving as a common liquid chamber for the pressure generation chambers 12 is formed at one end of the communication passage 15 in the second direction Y. In the present embodiment, the communication portion 13 is a liquid supply chamber that supplies ink to the individual flow paths. That is, the flow path forming substrate 10 is provided with a liquid flow path including a pressure generation chamber 12, a communication portion 13, an ink supply path 14, and a communication path 15.

  The ink supply path 14 is formed with a width narrower than that of the pressure generation chamber 12 in the first direction X, and maintains a constant flow path resistance of ink flowing into the pressure generation chamber 12 from the communication portion 13. Note that the ink supply path 14 is not limited to a configuration in which the width is reduced, and the height in the third direction Z may be reduced.

  On the surface of the flow path forming substrate 10 where the pressure generating chambers 12 are opened, there is a nozzle plate 20 in which nozzles 21 communicating with the vicinity of the end of each pressure generating chamber 12 on the side opposite to the ink supply path 14 are formed. It is fixed by an adhesive or a heat welding film. The nozzle plate 20 is made of glass ceramics, a silicon single crystal substrate, stainless steel, or the like.

  On the other hand, a diaphragm 50 is formed on the surface of the flow path forming substrate 10 opposite to the nozzle plate 20. The diaphragm 50 of this embodiment includes an elastic film 51 containing silicon oxide provided on the flow path forming substrate 10 side, and an insulator film 52 containing zirconium oxide provided on the elastic film 51. The liquid flow path such as the pressure generation chamber 12 is formed by anisotropically etching the flow path forming substrate 10 from the surface side where the nozzle plate 20 is joined. The opposite surface is defined by the elastic film 51.

The elastic film 51 containing silicon oxide (SiO ₂ ) can be formed, for example, by thermally oxidizing the flow path forming substrate 10 made of a silicon single crystal substrate. In the elastic film 51 containing silicon oxide formed in this way, the internal stress is a compressive stress. That is, in this embodiment, the elastic film 51 is a compressive stress film in which the internal stress has a compressive stress. The material of the elastic film 51 that is a compressive stress film is not limited to silicon oxide, and for example, silicon nitride (SiN), titanium oxide (TiO _x ), or the like may be used. That is, the elastic film 51 may be a single layer or a laminate of at least one material selected from silicon oxide (SiO ₂ ), silicon nitride (SiN), and titanium oxide (TiO _x ). Of course, the manufacturing method of the elastic film 51 is not limited to the above-described method, and can be formed by a gas phase method or a liquid phase method. The elastic film 51 is not limited to a film having internal stress having compressive stress, and may be a film having internal stress having tensile stress.

  The insulator film 52 containing zirconium oxide can be formed by a vapor phase method such as a sputtering method or a CVD method (chemical vapor deposition method), a liquid phase method such as a sol-gel method, or a MOD (Metal-Organic Decomposition) method. .

For example, by forming the insulator film 52 by a vapor phase method, a zirconium layer having a columnar shape or a crystal close to a column shape (in this case, the both are referred to as a columnar crystal) can be formed. Specifically, after forming a zirconium layer made of zirconium (Zr) by a vapor phase method, the zirconium layer can be thermally oxidized to form zirconium oxide (ZrO ₂ ). At this time, the stress of zirconium oxide can be adjusted by adjusting the temperature at which the zirconium layer is thermally oxidized, and the tensile stress increases as the firing temperature is increased. Further, zirconium oxide may be formed by a reactive sputtering method. In this case, compressive stress zirconium oxide is formed. Since the internal stress of the elastic film 51 containing silicon oxide is a compressive stress, the internal stress of the insulator film 52 is set as a tensile stress and the tensile stress is adjusted, so that vibration around the liquid supply port 16 described later will be described in detail. It is easy to suppress the breakage of the diaphragm 50 around the liquid supply port by neutralizing the internal stress of the plate 50.

  Note that the insulator film 52 formed by the vapor phase method has a crystal structure in which columnar particles are densely aggregated, and the diffusion of lead (Pb) from the piezoelectric layer 70 can be satisfactorily suppressed.

  Further, by forming the insulator film 52 by a liquid phase method, a zirconium oxide layer having granular crystals can be formed. Thus, the zirconium oxide insulator film 52 formed by the liquid phase method has a tensile stress as an internal stress. In addition, the zirconium oxide layer formed by the liquid phase method has a crystal structure in which small-diameter particles are loosely assembled, and can be a flexible film having a small Young's modulus. Therefore, the displacement amount of the insulator film 52, that is, the displacement amount of the diaphragm 50 can be increased. For this reason, it is preferable that the zirconium oxide which has a granular crystal | crystallization is included.

  Further, a zirconium oxide layer formed by a vapor phase method and a zirconium oxide layer formed by a liquid phase method may be combined. Thereby, adjustment of the internal stress of the insulator film 52 is facilitated. That is, it is also possible to adjust the internal stresses to cancel each other by laminating a zirconium oxide layer whose internal stress is tensile by the vapor phase method and a zirconium oxide layer whose internal stress is compressed by the liquid phase method. As a result, the internal stress of the diaphragm 50 around the liquid supply port, which will be described in detail later, is neutralized, and the breakage of the diaphragm 50 around the liquid supply port can be easily suppressed.

  The formation of the zirconium oxide layer having granular crystals is not limited to the liquid phase method, and may be formed by a vapor phase method. The formation of the zirconium oxide layer having columnar crystals is It is not limited to the phase method, and may be formed by a liquid phase method.

  The insulator film 52 containing zirconium oxide preferably has a tetragonal or cubic crystal structure. That is, it is preferable to use stabilized (partially stabilized) zirconia obtained by adding rare earth oxides such as yttrium oxide, calcium oxide, magnesium oxide and hafnium oxide to zirconium oxide, more preferably yttria stabilized zirconia (YSZ), The insulator film 52 containing zirconium oxide preferably contains yttrium. By using stabilized (partially stabilized) zirconia in this way, tetragonal crystals or cubic crystals can be stabilized even at room temperature, and the toughness of the insulator film 52 can be further increased, and the toughness of the diaphragm 50 can be increased. Specifically, it is possible to suppress the breakage of the diaphragm 50 around the liquid supply port 16 described later.

  In this embodiment, the elastic film 51 and the insulator film 52 are provided as the diaphragm 50. However, the present invention is not limited to this, and only the insulator film 52 may be provided as the diaphragm 50. . In addition to the elastic film 51 and the insulator film 52, another film may be provided as the diaphragm 50.

  In addition, the first electrode 60, the piezoelectric layer 70, and the second electrode 80 are laminated on the diaphragm 50 of the flow path forming substrate 10 by a film formation and lithography method to constitute the piezoelectric element 300. In the present embodiment, the piezoelectric element 300 is a pressure generating unit that causes a pressure change in the ink in the pressure generating chamber 12. Here, the piezoelectric element 300 is also referred to as a piezoelectric actuator, and refers to a portion including the first electrode 60, the piezoelectric layer 70, and the second electrode 80. In general, one of the electrodes of the piezoelectric element 300 is configured as a common electrode common to the plurality of piezoelectric elements 300, and the other electrode is configured as an individual electrode independent for each piezoelectric element 300. In the present embodiment, the first electrode 60 is a common electrode and the second electrode 80 is an individual electrode, but this may be reversed.

The first electrode 60 is a material that does not oxidize when the piezoelectric layer 70 is formed and can maintain conductivity. For example, a noble metal such as platinum (Pt) or iridium (Ir), or a lanthanum nickel oxide ( LNO), conductive oxides typified by iridium oxide (IrO ₂ ), and the like, and laminated films of these are preferably used.

  Further, as the first electrode 60, an adhesion layer for securing an adhesion force may be used between the above-described conductive material and the diaphragm 50. In this embodiment, although not particularly shown, titanium is used as the adhesion layer. As the adhesion layer, zirconium, titanium, titanium oxide, or the like can be used. That is, in the present embodiment, the first electrode 60 is formed of an adhesion layer made of titanium and at least one type of conductive layer selected from the above-described conductive materials.

The piezoelectric layer 70 is made of a piezoelectric material of the oxide having a polarization structure formed on the first electrode 60, for example, it may consist of a perovskite oxide represented by the general formula ABO _3, lead containing lead For example, a lead-based piezoelectric material or a lead-free piezoelectric material containing no lead can be used. The piezoelectric layer 70 is, for example, a liquid phase method such as a sol-gel method or a MOD (Metal-Organic Decomposition) method, or a PVD (Physical Vapor Deposition) method (gas phase method) such as a sputtering method or a laser ablation method. Can be formed.

  The second electrode 80 is preferably made of a material that can satisfactorily form an interface with the piezoelectric layer 70, and that can exhibit electrical conductivity and piezoelectric characteristics. Iridium (Ir), platinum (Pt), palladium (Pd), gold (Au) A conductive oxide represented by noble metal materials such as lanthanum nickel oxide (LNO) is preferably used. The second electrode 80 may be a stacked layer of a plurality of materials. In this embodiment, a laminated electrode of iridium and titanium (iridium is in contact with the piezoelectric layer 70) is used. The second electrode 80 is formed by a liquid phase method such as a PVD (Physical Vapor Deposition) method (gas phase method) such as a sputtering method or a laser ablation method, a sol-gel method, a MOD (Metal-Organic Decomposition) method, or a plating method. Can be formed. In addition, the characteristics of the piezoelectric layer 70 can be improved by performing a heat treatment after the formation of the second electrode 80.

  Such a second electrode 80 is formed only on the piezoelectric layer 70, that is, only on the surface of the piezoelectric layer 70 opposite to the flow path forming substrate 10.

  The piezoelectric element 300 is covered with a protective film 200. As the protective film 200, an insulating material having moisture resistance can be used. In the present embodiment, the protective film 200 is provided so as to cover the side surface of the piezoelectric layer 70, the side surface of the second electrode 80, and the peripheral edge of the upper surface. That is, the main part, which is a substantially central region on the upper surface of the second electrode 80, is not provided with the protective film 200, but is provided with an opening 201 that opens the main part of the second electrode 80.

  The opening 201 penetrates the protective film 200 in the third direction Z, which is the thickness direction, and opens in a rectangular shape along the second direction Y of the piezoelectric element 300. For example, the flow path forming substrate 10 can be formed by patterning after forming the protective film 200 over the entire surface.

  Thus, by covering the side surface of the piezoelectric layer 70 of the piezoelectric element 300 with the protective film 200, current leakage between the first electrode 60 and the second electrode 80 is suppressed, and the piezoelectric element 300 is destroyed. Can be suppressed. Further, by providing the opening 201, it is possible to suppress the displacement of the piezoelectric element 300 from being significantly reduced by the protective film 200. As a material of such a protective film 200, any material having moisture resistance may be used, and an inorganic insulating material, an organic insulating material, or the like can be used.

Examples of the inorganic insulating material that can be used as the protective film 200 include silicon oxide (SiO _X ), zirconium oxide (ZrO _X ), tantalum oxide (TaO _X ), aluminum oxide (AlO _X ), and titanium oxide (TiO _X ). At least one kind. As the inorganic insulating material for the protective film, it is particularly preferable to use aluminum oxide (AlO _x ), for example, alumina (Al ₂ O ₃ ), which is an inorganic amorphous material. The protective film 200 made of an inorganic insulating material can be formed by, for example, a MOD method, a sol-gel method, a sputtering method, a CVD method, or the like.

  Examples of the organic insulating material that can be used as the protective film 200 include at least one selected from an epoxy resin, a polyimide resin, a silicon resin, and a fluorine resin. The protective film 200 made of an organic insulating material can be formed by, for example, a spin coating method or a spray method.

  On the protective film 200, for example, a lead electrode 90 made of gold (Au) or the like is provided. The lead electrode 90 has one end connected to the second electrode 80 through a communication hole 202 provided in the protective film 200 and the other end opposite to the ink supply path 14 of the flow path forming substrate 10. The extended tip portion extends to the end portion, and is connected to a drive circuit 120 that drives a piezoelectric element 300 described later via a connection wiring 121.

  Further, a protective substrate 30 having a manifold portion 31 for supplying ink to the communication portion 13 is joined to the surface of the flow path forming substrate 10 on the piezoelectric element 300 side. In the present embodiment, the flow path forming substrate 10 and the protective substrate 30 are bonded using the adhesive 35. The manifold portion 31 of the protective substrate 30 is communicated with the communication portion 13 via a plurality of liquid supply ports 16, and ink from the manifold portion 31 is supplied to the communication portion 13 via the plurality of liquid supply ports 16.

  Such a diaphragm 50 is provided with a plurality of liquid supply ports 16 for supplying ink from the manifold portion 31 to the communication portion 13.

  The liquid supply port 16 has an opening smaller than the opening of the manifold portion 31 on the communication portion 13 side, and at least two or more liquid supply ports 16 are provided. Here, “provided with a plurality of liquid supply ports 16” means that two or more liquid supply ports 16 are provided for one communication portion 13. For example, when two or more communication portions 13 are provided on the flow path forming substrate 10, a plurality of liquid supply ports 16 may be provided for each of the communication portions 13. In other words, although the diaphragm 50 is provided with a plurality of liquid supply ports 16, the one provided with one liquid supply port 16 for one communicating portion 13 is the “multiple supply ports” of the present invention. Is not included. Further, by providing two or more liquid supply ports 16 for one communication portion 13, the diaphragm 50 is provided in a bowl shape in the opening on the protective substrate 30 side of the communication portion 13. Become.

  Such a liquid supply port 16 is provided through the diaphragm 50. Here, the liquid supply port 16 is provided so as to penetrate the diaphragm 50. The insulator film 52 containing zirconium oxide constituting the diaphragm 50 is provided on at least a part of the periphery of the liquid supply port 16. Say that it is. In other words, the fact that the insulator film 52 containing zirconium oxide that forms the diaphragm 50 is provided on at least a part of the periphery of the liquid supply port 16 means that the insulator film 52 that forms the diaphragm 50 has one insulator film 52. Even in the configuration in which the liquid supply port 16 is discontinuously provided in the circumferential direction, the insulating film 52 constituting the diaphragm 50 is continuously provided in the circumferential direction of one liquid supply port 16. The configuration is also included. Further, the fact that the insulator film 52 is provided on at least a part of the periphery of the liquid supply port 16 means that the insulator film 52 forms a part of the opening edge of the liquid supply port 16, the insulator A configuration in which the film 52 is formed in a part between the liquid supply ports 16 adjacent to each other, and a configuration in which the insulator film 52 is formed in a part between the liquid supply port 16 and the flow path wall. Including. In the present embodiment, the elastic film 51 and the insulator film 52 are continuously formed on the opening edge of the liquid supply port 16 in the circumferential direction.

  Thus, the diaphragm 50 provided with the plurality of liquid supply ports 16 functions as a filter that captures foreign matters such as bubbles and dust contained in the ink when supplying ink from the manifold portion 31 to the communication portion 13. . Since the diaphragm 50 provided with the plurality of liquid supply ports 16 functioning as a filter is provided in a bowl shape in the opening on the protective substrate 30 side of the communication portion 13, the manifold portion 31 moves to the communication portion 13. When pressure is applied by the supplied ink, it is not supported by the flow path forming substrate 10. However, by using the insulator film 52 containing zirconium oxide having high toughness as the diaphragm 50, even if the diaphragm 50 provided at the opening of the communication portion 13 is bent and deformed, the diaphragm 50 is broken such as cracks. Generation | occurrence | production can be suppressed. In particular, in this embodiment, the insulator film 52 containing zirconium oxide constituting the diaphragm 50 is formed continuously over the circumferential direction of the liquid supply port 16. Thus, by providing the insulator film 52 continuously over the circumferential direction of the liquid supply port 16, it is possible to further suppress cracks in the diaphragm 50 over the entire circumference of the liquid supply port 16. it can. Incidentally, when a vibration plate having low toughness is provided in a region where the communication portion 13 and the manifold portion 31 communicate with each other and the liquid supply port 16 is provided in the vibration plate 50, the vibration plate 50 is caused by the internal stress of the vibration plate 50 and the ink pressure. Breakage such as cracks occurs. In this embodiment, by using the insulator film 52 containing zirconium oxide having high toughness for the diaphragm 50 provided in the region where the communication portion 13 and the manifold portion 31 communicate with each other, the internal stress of the diaphragm 50 and the ink The occurrence of breakage such as cracks in the diaphragm 50 due to the pressure can be suppressed. Therefore, the recording head 1 with high reliability can be realized.

Here, the fracture toughness values of zirconium oxide, silicon nitride, and silicon oxide are shown in Table 1 below.

  As shown in Table 1, the toughness of zirconium oxide is greater than that of silicon nitride or silicon oxide. Therefore, by using the insulator film 52 containing zirconium oxide having high toughness for the diaphragm 50 provided in the region where the communication portion 13 and the manifold portion 31 communicate with each other, vibration is caused by internal stress of the diaphragm 50 and ink pressure. The occurrence of breakage such as cracks in the plate 50 can be suppressed.

  In this embodiment, since the insulator film 52 containing zirconium oxide is only used as the diaphragm 50, the diaphragm 50 does not need to be formed relatively thick with a multilayer structure of three to ten layers. In addition, it is possible to suppress the diaphragm 50 from inhibiting the variation of the piezoelectric element 300.

  Incidentally, the diaphragm 50 under the piezoelectric element 300 and the diaphragm 50 forming the liquid supply port 16 are made of different materials and different laminated structures, so that the diaphragm 50 of the portion where the liquid supply port 16 is formed is formed. Although destruction can be suppressed, a manufacturing process increases and cost will increase. In the present embodiment, the portion of the diaphragm 50 that overlaps the piezoelectric element 300 when viewed in plan from the third direction Z and the portion where the liquid supply port 16 is formed are provided in the same layer and continuously. Costs can be reduced by suppressing an increase in the number of steps.

  Further, since the diaphragm 50 has high toughness by using the insulator film 52 containing zirconium oxide, the diaphragm 50 around the liquid supply port 16 is cracked even if it is deformed by pressure fluctuation in the communication portion 13. Not likely to occur. Therefore, the diaphragm 50 around the liquid supply port 16 can be deformed by the pressure change in the communication portion 13 to absorb the pressure fluctuation in the communication portion 13. For this reason, it is possible to reduce or eliminate the compliance section described later in detail.

  In the present embodiment, the flow path forming substrate 10 provided with the pressure generation chamber 12 and the like, the diaphragm 50, and the piezoelectric element 300 are collectively referred to as a piezoelectric device.

  On the other hand, a piezoelectric element holding portion 32 is provided in a region of the protective substrate 30 facing the piezoelectric element 300. Since the piezoelectric element 300 is formed in the piezoelectric element holding portion 32, the piezoelectric element 300 is protected in a state hardly affected by the external environment. In addition, the piezoelectric element holding | maintenance part 32 may be sealed and does not need to be sealed.

  Examples of the material of the protective substrate 30 include glass, ceramic material, metal, resin, and the like, but it is preferable that the protective substrate 30 is formed of a material substantially the same as the coefficient of thermal expansion of the flow path forming substrate 10. In this embodiment, the silicon single crystal substrate made of the same material as the flow path forming substrate 10 is used.

  In addition, a drive circuit 120 for driving the piezoelectric element 300 is provided on the protective substrate 30. As the drive circuit 120, for example, a circuit board, a semiconductor integrated circuit (IC), or the like can be used. 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.

  Further, a compliance substrate 40 composed of a sealing film 41 and a fixing plate 42 is bonded on a region corresponding to the manifold portion 31 of the protective substrate 30. The sealing 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 surface of the manifold portion 31 is sealed by the sealing film 41. Yes. The fixing plate 42 is made of a hard material such as metal (for example, stainless steel (SUS) having a thickness of 30 μm). Since the region of the fixing plate 42 that faces the manifold portion 31 is an opening 43 that is completely removed in the thickness direction, one surface of the manifold portion 31 is formed of only a flexible sealing film 41. It is a sealed compliance section.

  In such an ink jet recording head 1 of this embodiment, ink is taken in from an external ink supply unit (not shown), filled with ink from the manifold portion 31 to the nozzle 21, and then in accordance with a recording signal from the drive circuit 120. By applying a voltage between each of the first electrode 60 and the second electrode 80 corresponding to the pressure generation chambers 12 to bend and deform the piezoelectric element 300 and the diaphragm 50, the pressure in each pressure generation chamber 12 is changed. Increases and ink is ejected from the nozzle 21.

  As described above, in the present embodiment, the piezoelectric device used in the recording head 1, which is an example of a liquid ejecting head that ejects liquid ink from the nozzle 21, includes the pressure generating chamber 12 that communicates with the nozzle 21. The flow path forming substrate 10 formed with the individual liquid chamber including the communication section 13 which is a liquid supply chamber communicating with the individual flow path, and the individual liquid chamber including the pressure generating chamber 12 of the flow path forming substrate 10 are communicated. Including a diaphragm 50 formed at a position corresponding to the portion 13, a plurality of liquid supply ports 16 formed in the communication portion 13, a first electrode 60, a piezoelectric layer 70, and a second electrode 80, A piezoelectric element 300 formed at a position corresponding to the individual liquid chamber including the pressure generating chamber 12 of the plate 50, and the liquid supply port 16 is provided through the vibration plate 50. Contains zirconium oxide.

  Thus, by providing the diaphragm 50 including zirconium oxide as the diaphragm 50 provided with the plurality of liquid supply ports 16, the toughness of the diaphragm 50 is improved, and the periphery of the plurality of liquid supply ports 16 is improved. The occurrence of breakage such as cracks in the diaphragm 50 can be suppressed. In addition, since the diaphragm 50 can be made thinner than when the diaphragm 50 is laminated in multiple layers such as three to ten layers, the diaphragm 50 is prevented from inhibiting the deformation of the piezoelectric element 300, A decrease in displacement of the piezoelectric element 300 can be suppressed.

  In the present embodiment, it is preferable that the crystal structure of zirconium oxide includes a tetragonal crystal or a cubic crystal at a position corresponding to the communication portion 13 of the diaphragm 50. In particular, it is preferable that the diaphragm 50 further contains yttrium at a position corresponding to the communication portion 13 of the diaphragm 50. That is, by using stabilized (partially stabilized) zirconia as the diaphragm 50, tetragonal crystals or cubic crystals can be stabilized even at room temperature, and the toughness of the diaphragm 50 can be further enhanced. The destruction of the surrounding diaphragm 50 can be suppressed.

  Further, the diaphragm 50 has an elastic film 51 that is a compressive stress film whose internal stress is a compressive stress at a position corresponding to the communication portion 13, and the liquid supply port 16 includes the diaphragm 50 having the elastic film 51. It is preferable to be provided through. According to this, by providing the diaphragm 50 with the elastic film 51 whose internal stress is compressive stress, it is possible to adjust the internal stress of the diaphragm 50 around the liquid supply port 16, such as cracks in the diaphragm 50. Destruction can be further suppressed.

  Moreover, it is preferable that a zirconium oxide contains a granular crystal. According to this, zirconium oxide can be made into a flexible film having a small Young's modulus, and the displacement amount of the diaphragm 50 can be increased.

  The diaphragm 50 includes an elastic film 51 that is a zirconium oxide film containing zirconium oxide, and the elastic film 51 is preferably formed continuously in the circumferential direction of the liquid supply port 16. That is, it is preferable that the elastic film 51 containing zirconium oxide constituting the diaphragm 50 is formed continuously over the circumferential direction of the liquid supply port 16. According to this, by providing the diaphragm 50, particularly the insulating film 52 continuously over the periphery of the liquid supply port 16, cracks in the diaphragm 50 around the liquid supply port 16 can be further suppressed. .

(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.

  Further, for example, in the above-described embodiment, the protective film 200 that covers the piezoelectric element 300 is exemplified as a configuration that is not provided in the region where the liquid supply port 16 is formed. However, the configuration is not particularly limited thereto. The film 200 may be provided in a region where the liquid supply port 16 is provided. That is, the diaphragm 50 and the protective film 200 may be laminated in the region between the manifold portion 31 and the communication portion 13, and the liquid supply port 16 may be provided through these.

  In the above-described embodiment, the communication portion 13 that is a liquid supply chamber is provided so as to communicate in common with all the individual flow paths, but is not particularly limited thereto, and the communication section 13 is not limited to this. It may be provided independently every time, and may be provided so that it may communicate for every group constituted by two or more individual flow paths. However, even if the communication portion 13 is provided for each individual flow path, it is sufficient that two or more liquid supply ports 16 are provided for one communication portion 13. In addition, when the communication portion 13 is communicated for each individual flow path or for each group composed of two or more individual flow paths, a flow path resistance is provided by the liquid supply port 16. 10 may not be provided with the ink supply path 14 or the communication path 15. Of course, in each of the above-described embodiments, at least one of the ink supply path 14 and the communication path 15 may not be provided.

  Furthermore, in the above-described embodiment, the configuration in which the diaphragm 50 is formed on the flow path forming substrate 10 is exemplified, but the present invention is not particularly limited thereto, and the diaphragm 50 may be bonded to the flow path forming substrate 10. Good.

  In the above-described embodiment, the pressure generation means for causing the pressure change in the pressure generation chamber 12 has been described using the thin film type piezoelectric element 300. However, the present invention is not particularly limited thereto, and, for example, a green sheet is pasted. It is possible to use a thick film type piezoelectric element formed by a method such as the above, a longitudinal vibration type piezoelectric element in which piezoelectric materials and electrode forming materials are alternately stacked and expanded and contracted in the axial direction.

  The ink jet recording head 1 described above constitutes a part of an ink jet recording head unit having an ink flow path communicating with an ink cartridge or the like, and is mounted on an ink jet recording apparatus. FIG. 5 is a schematic view showing an example of the ink jet recording apparatus.

  In the ink jet recording apparatus I shown in FIG. 5, a plurality of recording heads 1 are detachably provided with ink cartridges 2 constituting ink supply means, and a carriage 3 on which the recording heads 1 are mounted is attached to the apparatus main body 4. The carriage shaft 5 is provided so as to be movable in the axial direction.

  Then, the driving force of the driving motor 6 is transmitted to the carriage 3 via a plurality of gears and a timing belt 7 (not shown), so that the carriage 3 on which the recording head 1 is mounted is moved along the carriage shaft 5. On the other hand, the apparatus main body 4 is provided with a conveyance roller 8 as a conveyance means, and a recording sheet S which is a recording medium such as paper is conveyed by the conveyance roller 8. Note that the conveyance means for conveying the recording sheet S is not limited to the conveyance roller, and may be a belt, a drum, or the like.

  Note that the ink jet recording apparatus I described above has a configuration in which the ink cartridge 2 as the ink supply means is mounted on the carriage 3. However, the present invention is not particularly limited thereto, and for example, the ink supply means such as an ink tank is connected to the apparatus main body. The ink supply unit and the recording head 1 may be connected to each other via a supply pipe such as a tube. Further, the ink supply unit may not be mounted on the ink jet recording apparatus.

  In the ink jet recording apparatus I described above, the recording head 1 is mounted on the carriage 3 and moves in the main scanning direction. However, the present invention is not limited to this. For example, the recording head 1 is fixed, The present invention can also be applied to a so-called line type recording apparatus that performs printing only by moving a recording sheet S such as paper in the sub-scanning direction.

  Furthermore, the present invention is intended for a wide range of liquid jet heads in general, for example, for manufacturing recording heads such as various ink jet recording heads used in image recording apparatuses such as printers, and color filters such as liquid crystal displays. The present invention can also be applied to a coloring material ejecting head, an organic EL display, an electrode material ejecting head used for forming electrodes such as an FED (field emission display), a bioorganic matter ejecting head used for biochip manufacturing, and the like. Further, although the ink jet recording apparatus I has been described as an example of the liquid ejecting apparatus, the liquid ejecting apparatus using the other liquid ejecting heads described above can also be used.

I: Inkjet recording apparatus (liquid ejecting apparatus), 1 ... Inkjet recording head (
(Liquid ejecting head), 2 ... ink cartridge, 3 ... carriage, 4 ... main body, 5 ... carriage shaft, 6 ... drive motor, 7 ... timing belt, 8 ... transport roller, 10 ... flow path forming substrate, 11 ... partition wall, 12 ... Pressure generation chamber (individual flow path), 13 ... Communication part (liquid supply chamber), 14
... ink supply path (individual flow path), 15 ... communication path (individual flow path), 16 ... liquid supply port, 20 ... nozzle plate, 21 ... nozzle, 30 ... protective substrate, 31 ... manifold section, 32 ... piezoelectric element holding 35, adhesive, 40, compliance substrate, 41, sealing film, 42, fixing plate, 43
DESCRIPTION OF SYMBOLS ... Opening part, 50 ... Diaphragm, 51 ... Elastic film, 52 ... Insulator film, 60 ... 1st electrode, 70 ... Piezoelectric layer, 80 ... 2nd electrode, 90 ... Lead electrode, 120 ... Drive circuit, 121 ... Connection wiring, 20
DESCRIPTION OF SYMBOLS 0 ... Protective film, 201 ... Opening part, 202 ... Communication hole, 300 ... Piezoelectric element, S ... Recording sheet, X
... 1st direction, Y ... 2nd direction, Z ... 3rd direction

Claims (8)

A piezoelectric device used in a liquid ejecting head that ejects liquid from a nozzle,
A flow path forming substrate in which an individual liquid chamber communicating with the nozzle and a liquid supply chamber communicating with the individual liquid chamber are formed;
A diaphragm formed at a position corresponding to the individual liquid chamber and the liquid supply chamber of the flow path forming substrate;
A plurality of liquid supply ports formed in the liquid supply chamber;
A piezoelectric element including a first electrode, a piezoelectric layer, and a second electrode, and formed at a position corresponding to the individual liquid chamber of the diaphragm;
Comprising
The liquid supply port is provided through the diaphragm,
The diaphragm includes the zirconium oxide.   The piezoelectric device according to claim 1, wherein the crystal structure of the zirconium oxide includes a tetragonal crystal or a cubic crystal.   The piezoelectric device according to claim 2, wherein the diaphragm further includes yttrium. The diaphragm has a compressive stress film whose internal stress is compressive stress at a position corresponding to the liquid supply chamber,
The piezoelectric device according to claim 1, wherein the liquid supply port is provided so as to penetrate the diaphragm having the compressive stress film.   The piezoelectric device according to claim 1, wherein the zirconium oxide includes granular crystals.   2. The diaphragm includes a zirconium oxide film containing the zirconium oxide, and the zirconium oxide film is continuously formed in a circumferential direction of the liquid supply port. The piezoelectric device as described in any one of -5.   A liquid ejecting head comprising the piezoelectric device according to claim 1.   A liquid ejecting apparatus comprising the liquid ejecting head according to claim 7.

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