JP2010199508A - Method of manufacturing piezoelectric actuator, and method of manufacturing liquid transfer apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily manufacture a piezoelectric actuator having a thin vibrating membrane as a single element. <P>SOLUTION: A separating membrane 81 (a base) formed of lead at a lower temperature than a predetermined temperature in an annealing treatment process is formed on a stage 80. Then, a piezoelectric layer 32 is formed by depositing particles of piezoelectric material on a surface of the separating membrane 81. The vibrating membrane 31 is formed by depositing particles of stainless steel on a surface of the piezoelectric layer 32 by an AD method. The separating membrane 81, vibrating membrane 31, and piezoelectric layer 32 are heated to a predetermined temperature, and heat treatment is carried out on the piezoelectric layer 32. At that time, the separating membrane 81 is molten in the annealing treatment process, the vibrating membrane 31 and piezoelectric layer 32 are removed from the stage 80, and are tilted to remove molten lead. After that, a plurality of individual electrodes 33 are respectively formed in regions opposite to a plurality of pressure chambers 14 on the piezoelectric layer 32. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a piezoelectric actuator and a method for manufacturing a liquid transfer device.

  2. Description of the Related Art Conventionally, there is a piezoelectric actuator that has a diaphragm and a piezoelectric layer formed on the diaphragm and drives an object using deformation (piezoelectric strain) of the piezoelectric layer when an electric field is applied. As an example of use of such a piezoelectric actuator, it is used to apply pressure to liquid in a pressure chamber by being joined to a flow path unit in which a liquid flow path including a pressure chamber is formed to constitute an ink jet head. It has been known. As described above, the piezoelectric actuator is used by being connected to the drive target.

  For example, Patent Literature 1 and Patent Literature 2 disclose examples in which a piezoelectric actuator is used for liquid ejection of an inkjet head. In the method of manufacturing an ink jet head described in Patent Document 1 and Patent Document 2, a diaphragm is first formed on a metal plate that is a part of a flow path unit and in which a pressure chamber is to be formed. A piezoelectric layer is formed on the surface opposite to the metal plate. A pressure chamber is formed by etching in the metal plate on which the vibration plate and the piezoelectric layer are formed.

Japanese Patent Laying-Open No. 2006-006096 (FIG. 14) JP 2006-175600 A (FIG. 4)

  However, in the inkjet head manufacturing method described in Patent Document 1 and Patent Document 2, the diaphragm and the piezoelectric layer are formed on the metal plate that is a part of the flow path unit that is driven by the piezoelectric actuator. The piezoelectric actuator is manufactured by, and the piezoelectric actuator composed of the diaphragm and the piezoelectric layer is not manufactured alone. That is, at least a part of the drive target is integrated during the manufacturing process of the piezoelectric actuator. Therefore, it is necessary to manufacture the piezoelectric actuator while taking into consideration the shape material and manufacturing method of the flow path unit, and the degree of freedom in designing the inkjet head is reduced. In addition, the shape material and manufacturing method of the piezoelectric actuator itself are affected, and the degree of freedom in designing the ink jet head is reduced.

  For example, if a pressure chamber is formed in a metal plate by etching after forming the vibration plate and the piezoelectric layer on the metal plate, the vibration plate and the piezoelectric layer may also be etched. Forming such that it is not etched makes it very difficult to control the etching. In addition, it is conceivable that the material of the diaphragm and the piezoelectric layer is a material that is not etched, but in this case, the materials that can form the diaphragm and the piezoelectric layer are limited. In addition, when a pressure chamber is formed on the metal plate by a method other than etching, the method for forming the pressure chamber on the metal plate is limited.

  Accordingly, an object of the present invention is to provide a method for manufacturing a piezoelectric actuator and a method for manufacturing a liquid transfer device, in which a piezoelectric actuator having a thin vibration film can be easily manufactured as a single unit, and a highly flexible design is possible. .

  The method for manufacturing a piezoelectric actuator of the present invention includes a film forming step of forming a vibration film and a piezoelectric layer on one surface of a base material with a material having a melting point higher than the melting point or thermal decomposition temperature of the base material, After the film forming step, a removing step of removing the substrate by heating to a predetermined temperature lower than the melting point of the vibrating membrane and the piezoelectric layer and higher than the melting point or thermal decomposition temperature of the substrate. I have.

  According to the method for manufacturing a piezoelectric actuator of the present invention, the formed vibration film and piezoelectric layer can be easily detached from the base material, and a piezoelectric actuator having a thin vibration film can be manufactured alone. In this way, by using a piezoelectric actuator manufactured as a single unit, it is possible to design with a high degree of freedom without depending on the shape material or manufacturing method of the driving target connected to the piezoelectric actuator and driven.

  In the film formation step, the piezoelectric layer is formed by an aerosol deposition method, and after the film formation step, the piezoelectric layer is heated at the predetermined temperature at which the piezoelectric layer can be annealed. The heating step also serves as the removal step, and it is preferable that both the base material be heated and removed. When the piezoelectric layer is formed by the aerosol deposition method in the film forming step, a step of heating the piezoelectric layer is necessary as an annealing process in order to improve the piezoelectric characteristics of the piezoelectric layer. According to this, since the heating process also serves as the removal process, the manufacturing process can be simplified.

  Further, in the film formation step, the piezoelectric layer is formed by a sol-gel method, and after the film formation step, a heating step of heating the piezoelectric layer at the predetermined temperature capable of removing the solvent in the gel is further included. The heating step also serves as the removing step, and both the substrate may be heated and removed. When the piezoelectric layer is formed by the sol-gel method in the film forming step, a step of heating the piezoelectric layer is required in order to volatilize and remove the solvent in the gel. According to this, since the heating process also serves as the removal process, the manufacturing process can be simplified.

  In the film forming step, it is preferable that the piezoelectric film is formed on the one surface of the base material, and then the vibration film is formed on a surface of the piezoelectric layer opposite to the base material. According to this, if the surface of the substrate is smooth, the surface of the piezoelectric layer facing the substrate can be formed smoothly, and the film thickness of the piezoelectric layer can be made uniform over the entire surface.

  Furthermore, the base material is formed of a lead-containing material, and in the film forming step, the piezoelectric layer is preferably formed of a piezoelectric material containing lead on the one surface of the base material. When the base material and the piezoelectric layer are heated, the material forming the base material diffuses and reaches the piezoelectric layer. According to this, since the base material is also made of a material containing lead in contrast to the piezoelectric layer made of a material containing lead, even if lead diffused from this base material reaches the piezoelectric layer. Compared with the case where other materials diffuse, the piezoelectric layer is hardly adversely affected. Moreover, it is possible to prevent lead from diffusing from the piezoelectric layer to the base material.

  The liquid transfer device manufacturing method of the present invention includes a flow path unit in which a liquid flow path including a pressure chamber is formed, a vibration film disposed on the flow path unit so as to cover at least the pressure chamber, and the vibration film. A piezoelectric actuator including a piezoelectric layer disposed on the opposite side of the pressure chamber, and a method of manufacturing a liquid transfer device, wherein one surface of the substrate has a melting point or thermal decomposition temperature higher than that of the substrate. A film forming step of forming the vibration film and the piezoelectric layer with a material having a high melting point; and after the film forming step, the melting point of the base material is lower than the melting point of the vibration film and the piezoelectric layer and A removal step of heating and removing the base material at a predetermined temperature higher than a thermal decomposition temperature; and after the removal step, on the opposite side of the surface on which the piezoelectric layer of the vibrating membrane is disposed on the flow path unit The vibrating membrane makes the pressure chamber face to face The Migihitsuji, and a, a bonding step of bonding the flow path unit and the vibrating membrane.

  According to the method for manufacturing a liquid transfer device of the present invention, the formed vibration film and piezoelectric layer can be easily detached from the substrate, and a piezoelectric actuator having a thin vibration film can be manufactured alone. Further, since the piezoelectric actuator is joined to the flow path unit after manufacturing, the flow path unit can be designed with a high degree of freedom without depending on its shape, material, manufacturing method, and the like.

  In the film formation step, it is preferable that the bonding step is performed after the piezoelectric layer is formed by an aerosol deposition method. According to this, there is no possibility that particles of the piezoelectric material that were sprayed on the vibration film in the film formation process but did not deposit on the vibration film enter the liquid flow path formed in the flow path unit. A step of removing particles in the liquid flow path, such as a cleaning process performed when particles enter the flow path, becomes unnecessary.

  The formed vibration film and piezoelectric layer can be easily detached from the substrate, and a piezoelectric actuator having a thin vibration film can be manufactured alone. Thus, by using a piezoelectric actuator manufactured as a single unit, it is possible to design with a high degree of freedom without depending on the shape material or manufacturing method of the target connected to the piezoelectric actuator and driven.

1 is a schematic configuration diagram of an inkjet printer according to an embodiment. It is a top view of an inkjet head. FIG. 3 is a partially enlarged view of FIG. 2. FIG. 4 is a cross-sectional view taken along line AA in FIG. 3. It is process drawing which shows the manufacturing process of an inkjet head, (a) is a separation membrane formation process, (b) is a piezoelectric layer formation process, (c) is a vibration film formation process, (d) is a removal process, (e) is a process It is a joining process. It is a schematic block diagram in the chamber at the time of a piezoelectric layer formation process.

  Next, a preferred embodiment of the present invention will be described. The present embodiment is an example in which the present invention is applied to an inkjet head as a liquid transfer device that discharges ink from a nozzle while transferring ink to the nozzle in an ink flow path.

  First, an ink jet printer having this ink jet head will be described. FIG. 1 is a schematic configuration diagram of an ink jet printer according to the present embodiment. As shown in FIG. 1, an inkjet printer 100 includes a carriage 2 that can reciprocate in the left-right direction (scanning direction) in FIG. 1, and a serial that is provided on the lower surface of the carriage 2 and that ejects ink onto recording paper P. The ink jet head 1 of a type | mold and the conveyance roller 3 etc. which convey the recording paper P to the front of FIG.

  The ink jet printer 100 ejects ink onto the recording paper P from the nozzles 20 (see FIGS. 2 to 4) of the ink jet head 1 while reciprocating the ink jet head 1 together with the carriage 2 in the scanning direction. The recording paper P on which the image and the like are recorded is discharged forward by the conveying roller 3.

  Next, the inkjet head 1 will be described. FIG. 2 is a plan view of the inkjet head. FIG. 3 is a partially enlarged view of FIG. 4 is a cross-sectional view taken along line AA in FIG. As shown in FIGS. 2 to 4, the inkjet head 1 is disposed on the upper surface of the flow path unit 4 in which an ink flow path including a number of nozzles 20 and pressure chambers 14 is formed, And a piezoelectric actuator 5 that applies pressure to the ink in the chamber 14.

  First, the flow path unit 4 will be described. The flow path unit 4 has the same outer shape in plan view of the cavity plate 41, the base plate 42, the aperture plate 43, the two manifold plates 44 and 45, the damper plate 46, the cover plate 47, and the nozzle plate 48 in order from the upper layer. A total of eight plates 41 to 48 are joined in a laminated state.

  Of the eight plates 41 to 48, the lowermost nozzle plate 48 is formed of a synthetic resin material such as polyimide, and the remaining seven plates 41 to 47 are each a metal plate such as a stainless steel plate. . The seven plates 41 to 47 are joined to each other by an adhesive or metal diffusion. Further, the plates 47 and 48 are joined to each other by an adhesive.

  Among the eight plates 41 to 48, a plurality of pressure chambers 14 are formed penetrating in the thickness direction in the cavity plate 41 located in the uppermost layer. Each pressure chamber 14 has a substantially elliptical planar shape with the scanning direction as a longitudinal direction, and the pressure chamber 14 is formed when a vibration film 31 (to be described later) and a base plate 42 are stacked on the upper side. Is done. The plurality of pressure chambers 14 are arranged in two rows in the paper feeding direction (vertical direction in FIG. 2).

  The base plate 42 is formed with through holes 15 and 16 communicating with both end portions of the pressure chamber 14 in the longitudinal direction. The aperture plate 43 communicates with the through hole 15 of the base plate 42 and extends along the longitudinal direction of the pressure chamber 14, and is a throttle channel 52 formed by half etching at a position overlapping a manifold channel 17 described later in plan view. And a through hole 58 communicating with the through hole 16 is formed.

  In the two manifold plates 44 and 45, manifold forming holes 17 a and 17 b that extend in the paper feeding direction and respectively form part of the manifold channel 17 are formed corresponding to the rows of the pressure chambers 14. . Then, in a state where these two manifold forming holes 17a and 17b are vertically overlapped, the manifold plate 17 is formed in two rows in the paper feed direction by being blocked from the upper and lower sides by the aperture plate 43 and the damper plate 46. Yes.

  These two rows of manifold channels 17 extend in the paper feed direction so as to overlap the manifold forming holes 17a, 17b side portions of the pressure chambers 14 arranged in two rows in plan view. These two rows of manifold channels 17 communicate with ink supply ports 18 formed in the cavity plate 41, and ink is supplied from an ink tank (not shown) to the manifold channels 17 via the ink supply ports 18. The ink supplied to the manifold channel 17 is supplied to the plurality of pressure chambers 14. That is, the manifold channel 17 is a common ink chamber that supplies ink to the plurality of pressure chambers 14 in common. Further, the two manifold plates 44 and 45 are formed with through holes 59 and 60 that are continuous with the through hole 58 of the aperture plate 43, respectively.

  A recess 61 is formed by half-etching at a position on the lower surface of the damper plate 46 that overlaps the manifold channel 17 in plan view. That is, the damper plate 46 is locally thin at the portion where the recess 61 is formed, and this thin portion functions as a damper portion that attenuates ink pressure fluctuations in the manifold channel 17. Further, the damper plate 46 is formed with a through hole 62 that is continuous with the through hole 60 of the manifold plate 45. The cover plate 47 is formed with a through hole 63 communicating with the through hole 62 of the damper plate 46.

  Of the eight plates 41 to 48, the nozzle 20 that communicates with the through hole 63 of the cover plate 47 is formed in the nozzle plate 48 that is positioned at the lowest layer. As shown in FIG. 2, the plurality of nozzles 20 are disposed so as to overlap with the ends of the plurality of pressure chambers 14 arranged in two rows in the paper feeding direction on the opposite side to the manifold channel 17, respectively. Two nozzle rows are configured.

  When the eight plates 41 to 48 described above are joined in a stacked state, the flow path unit 4 branches from the manifold flow path 17 communicating with the ink supply port 18 and passes through the pressure chamber 14. An ink flow path reaching the nozzle 20 is formed.

  Next, the piezoelectric actuator 5 will be described. As shown in FIG. 4, the piezoelectric actuator 5 includes a vibration film 31, a piezoelectric layer 32, and a plurality of individual electrodes 33.

  The vibration film 31 is a thin metal film made of stainless steel. The vibration film 31 is disposed on the upper surface of the cavity plate 41, and is grounded at a position not shown and held at the ground potential.

  The piezoelectric layer 32 is a layer containing a piezoelectric material mainly composed of lead zirconate titanate, which is a mixed crystal of lead titanate and lead zirconate, and is formed on the upper surface (opposite to the pressure chamber 14) of the vibration film 31. , And are continuously arranged across the plurality of pressure chambers 14. The piezoelectric layer 32 is previously polarized in the thickness direction.

  The plurality of individual electrodes 33 have a substantially elliptical planar shape that is slightly smaller than the pressure chamber 14, and are arranged on the upper surface of the piezoelectric layer 32 so as to overlap with substantially central portions of the plurality of pressure chambers 14 in plan view. Has been. The individual electrode 33 is made of a conductive material such as platinum, palladium, gold, or silver. The end of the individual electrode 33 on the opposite side to the nozzle 20 in the longitudinal direction extends to a portion not facing the pressure chamber 14 in the scanning direction, and the tip thereof serves as a connection terminal connected to an FPC (not shown). . A driving potential is applied to the individual electrode 33 via an FPC by a driver IC (not shown).

  Here, the operation of the piezoelectric actuator 5 during ink ejection will be described. When ink is ejected from a certain nozzle 20, a driving potential is applied from the driver IC to the individual electrode 33 corresponding to the pressure chamber 14 communicating with the nozzle 20. Then, a potential difference is generated between the individual electrode 33 to which the driving potential is applied and the vibration film 31 held at the ground potential, and an electric field parallel to the thickness direction is generated in the piezoelectric layer 32 sandwiched between the two. Since the direction of the electric field coincides with the polarization direction of the piezoelectric layer 32, the piezoelectric layer 32 polarized in the thickness direction contracts in a horizontal direction perpendicular to the direction of the electric field (piezoelectric lateral effect). As a result, the portion of the vibrating membrane 31 facing the pressure chamber 14 is deformed so as to protrude toward the pressure chamber 14 (unimorph deformation). At this time, the volume of the pressure chamber 14 decreases, the pressure of the ink inside the pressure chamber 14 increases, and ink is ejected from the nozzle 20 communicating with the pressure chamber 14.

  Next, a method for manufacturing the inkjet head 1 will be described. 5A and 5B are process diagrams showing the manufacturing process of the inkjet head, in which FIG. 5A is a separation film forming process, FIG. 5B is a piezoelectric layer forming process, FIG. 5C is a vibration film forming process, FIG. e) is a joining process. FIG. 6 is a schematic configuration diagram in the chamber during the piezoelectric layer forming step. The inkjet head 1 according to the present embodiment is manufactured by first manufacturing the piezoelectric actuator 5 alone and then joining the flow path unit 4.

  First, as shown in FIG. 5 (a), a predetermined temperature (for example, 800 ° C .: below, annealing treatment temperature) having a melting point on the surface of a stage 80 in a chamber in which an AD method described later is performed will be described later. A flat plate-like separation membrane 81 (base material) made of lead lower than the above is formed by sputtering. The formation of the separation film 81 on the stage 80 may be performed in a chamber where the AD method is performed, or if the chamber where the AD method and the sputtering method are separate chambers, the stage is placed in the chamber used for the sputtering method. After 80 is attached to form the separation membrane 81, the stage 80 may be removed and attached to the chamber in which the AD method is performed.

  Next, as shown in FIG. 5B, an aerosol deposition method (AD method) using a piezoelectric material mainly composed of lead zirconate titanate which is a mixed crystal of lead titanate and lead zirconate. Thus, the piezoelectric layer 32 is formed by depositing particles of the piezoelectric material on the surface of the separation film 81 (piezoelectric layer forming step).

  In the AD method, as shown in FIG. 6, the inside of the chamber 70 is evacuated, and an aerosol chamber (not shown) in which a mixture (aerosol) of particles and gas (carrier gas) forming the chamber and the piezoelectric layer 32 is enclosed. Due to the pressure difference between them, the aerosol is sprayed onto the vibrating membrane 31 from the spray nozzle 73 communicating with the aerosol chamber, the particles collide with the separation membrane 81 at a high speed, and the stage is reciprocated in the horizontal direction to separate the separation membrane 81. This is a film forming method in which particles of piezoelectric material are deposited.

  Subsequently, as shown in FIG. 5C, the vibration film 31 is formed by depositing stainless particles on the surface of the piezoelectric layer 32 by the AD method (vibration film forming step). The piezoelectric layer forming step and the vibration film forming step in the present embodiment correspond to the film forming step in the present invention.

  The aerosol of piezoelectric material particles and gas sealed in the aerosol chamber is replaced with an aerosol of stainless steel particles and gas, or the spray nozzle 73 is connected to the aerosol of piezoelectric material particles and gas. By switching from the aerosol chamber in which is encapsulated to the aerosol chamber in which the aerosol of stainless particles and gas is encapsulated, the piezoelectric layer forming step and the vibration film forming step can be performed by the AD method in the same chamber. Further, after the stage 80 in the chamber 70 is made detachable, the stage 80 is attached in a chamber having an aerosol chamber in which aerosol of piezoelectric material particles and gas is sealed, and the piezoelectric layer forming step is performed. Alternatively, the stage 80 may be removed, and the stage 80 may be attached to a chamber having an aerosol chamber in which an aerosol of stainless particles and gas is sealed, and the vibration film forming process may be performed.

  When the piezoelectric layer 32 is formed by the AD method, the piezoelectric characteristics necessary for deforming the vibration film 31 cannot be obtained if particle miniaturization or lattice defects occur in the piezoelectric layer 32. Therefore, in order to grow the particle crystal of the piezoelectric material and repair the lattice defects in the crystal to improve the piezoelectric characteristics, the separation film 81, the vibration film 31 and the piezoelectric layer 32 are heated to the annealing temperature to thereby reduce the piezoelectricity. A heat treatment is performed on the layer 32 (annealing process).

  At this time, as shown in FIG. 5D, since the melting point of the separation film 81 made of lead is about 327 ° C. and lower than the annealing temperature, it melts in the annealing process, and the vibration film 31 and the piezoelectric layer 32 are melted. Is removed from the stage 80 and the dissolved lead is removed by tilting the vibration film 31 and the piezoelectric layer 32. At this time, since the diaphragm 31 is thin, it is difficult to carry. In addition, the piezoelectric layer 32 made of lead zirconate titanate is fragile and easily broken. However, since the vibration film 31 and the piezoelectric layer 32 are laminated and integrated, it is easy to carry. That is, since the vibrating membrane 31 is not carried alone, a desired thin vibrating membrane 31 can be formed without considering the portable thickness, and the vibrating membrane 31 reinforces the piezoelectric layer 32. The piezoelectric layer 32 can be made difficult to break. Further, if the vibration film 31 is thin, it easily deforms, and the amount of deformation of the pressure chamber 14 increases. Therefore, a high pressure can be applied to the ink in the pressure chamber 14, and the drive voltage applied from the driver IC is set to a low voltage. can do. Moreover, since the annealing process also serves as a removal process for heating and removing the separation membrane 81, the manufacturing process can be simplified.

  Thereafter, a plurality of individual electrodes 33 are formed in regions facing the plurality of pressure chambers 14 on the piezoelectric layer 32. The plurality of individual electrodes 33 are formed at a time by screen printing, vapor deposition, sputtering, or the like. Thereby, the piezoelectric actuator 5 is completed.

  Next, the pressure chamber 14 is added to the cavity plate 41, the base plate 42, the aperture plate 43, the two manifold plates 44 and 45, the damper plate 46, and the cover plate 47, which are metal plates among the plates constituting the flow path unit 4. And a hole penetrating in the thickness direction constituting the ink flow path such as the manifold flow path 17 is formed. Since these plates 41 to 47 are made of a metal material, holes penetrating in the thickness direction constituting the ink flow path can be easily formed by etching. In addition, a throttle channel 52 is formed in the aperture plate 43 and a recess 61 is formed in the damper plate 46 by half etching. A plurality of nozzles 20 are formed on a synthetic resin nozzle plate 48 by laser processing or the like.

  Then, as shown in FIG. 5E, the piezoelectric actuator 5 and the eight plates 41 to 48 constituting the flow path unit 4 are laminated and bonded with an adhesive or the like (bonding step), and the inkjet head 1 is completed. It should be noted that metal plates such as a cavity plate 41, a base plate 42, an aperture plate 43, two manifold plates 44 and 45, a damper plate 46, and a cover plate 47 are laminated in advance to form metal diffusion bonding. Alternatively, the seven plates 41 to 47 and the nozzle plate 48 that are already bonded to the vibration film 31 on which the piezoelectric layer 32 is formed may be laminated and bonded with an adhesive. Further, the nozzle plate 48 may be formed of a metal material such as stainless steel in the same manner as the other seven plates 41 to 47 constituting the flow path unit 4, and in that case, the nozzle plate 48 is also formed of seven pieces. These plates 41 to 47 may be laminated simultaneously and joined by metal diffusion bonding.

  As described above, according to the manufacturing method of the ink jet head 1 described above, the vibration film 31 and the piezoelectric layer 32 formed from the separation film 81 can be easily removed, and the piezoelectric actuator 5 having the thin vibration film 31 is manufactured alone. be able to. Thus, by using the piezoelectric actuator 5 manufactured as a single unit for manufacturing the inkjet head 1, a highly flexible design that does not depend on the shape material of the flow path unit, the manufacturing method, or the like is possible.

  Further, since the eight plates 41 to 48 constituting the flow path unit 4 are joined in the joining step performed after the piezoelectric layer forming step, the eight plates 41 to 48 do not exist in the chamber. Therefore, there is a possibility that particles of the piezoelectric material that have been sprayed on the separation film 81 in the piezoelectric layer forming step but not deposited on the separation film 81 may enter the ink flow paths formed on the eight plates 41 to 48. In other words, a step of removing particles in the ink flow path such as a cleaning process that is performed when the particles enter the ink flow path is not necessary.

  Further, since the separation film 81 is formed by the sputtering method, the surface of the separation film 81 is a smooth surface. Then, in the piezoelectric layer forming step, the surface of the piezoelectric layer 32 facing the separation film 81 can be formed smoothly, and the film thickness of the piezoelectric layer 32 can be made uniform over the entire surface. As a result, the amount of contraction of each polarized region of the piezoelectric layer 32 becomes uniform, and there is no variation in the pressure applied to the ink in each pressure chamber 14 of the flow path unit 4. Further, the smooth surface of the piezoelectric layer 32 is a surface on which the plurality of individual electrodes 33 are formed, and the plurality of individual electrodes 33 can be easily formed.

  Further, when the separation film 81 is formed of a metal material, the metal material diffused from the separation film 81 reaches the piezoelectric layer 32 until it is melted by heating in the annealing process. Therefore, in the present embodiment, since the separation film 81 is formed of lead with respect to the piezoelectric layer 32 formed of a material containing lead, the lead diffused from the separation film 81 reaches the piezoelectric layer 32. Even if other metal materials are diffused, the piezoelectric layer 32 is less likely to be adversely affected. Further, it is possible to prevent lead from diffusing from the piezoelectric layer 32 to the separation membrane 81.

  Next, modified examples in which various changes are made to the present embodiment will be described. However, components having the same configuration as in the above embodiment are given the same reference numerals and description thereof is omitted as appropriate.

  In this embodiment, after the piezoelectric layer 32 is formed on the separation film 81, the vibration film 31 is formed on the piezoelectric layer 32. However, after the vibration film 31 is formed on the separation film 81, the vibration film 31 is formed. A piezoelectric layer 32 may be formed on the film 31. In the film formation process of the piezoelectric layer 32 and the vibration film 31 by the AD method, the piezoelectric layer 32 or the vibration film formed next on the piezoelectric layer 32 or the vibration film 31 previously formed on the surface of the separation film 81. Since the aerosol that is the material of the material 31 collides at high speed, after the piezoelectric layer 32 or the vibrating membrane 31 is formed first on the surface of the separation membrane 81, the piezoelectric layer 32 or the vibrating membrane is formed. It is preferable to form the thinner one of the remaining piezoelectric layer 32 or vibration film 31 on the surface of 31.

  In the present embodiment, the piezoelectric layer 32 is formed by the AD method, but may be formed by a sol-gel method. At this time, in order to volatilize the solvent in the gel, a step of heating at 600 to 700 ° C. is necessary, and this step corresponds to the heating step in the present invention. That is, the separation membrane 81 can be removed in this heating step. Further, the piezoelectric layer 32 may be formed by other film forming methods such as a sputtering method other than the AD method or the sol-gel method, a chemical vapor deposition method, or a hydrothermal synthesis method. At this time, the step of heating and removing the separation film 81 is performed after the step of forming the piezoelectric layer 32 and the vibration film 31.

  Further, although the piezoelectric layer 32 is continuously disposed across the plurality of pressure chambers 14, it may be disposed individually in each of the plurality of pressure chambers 14. According to this, in the case where there are a plurality of piezoelectric layers 32, it is possible to prevent so-called crosstalk in which the piezoelectric strain generated when a potential is applied to one piezoelectric layer 32 affects the other piezoelectric layers 32. At this time, after forming the plurality of piezoelectric layers 32, it is not necessary to arrange the piezoelectric layers 32 on the vibration film 31 at positions corresponding to the plurality of pressure chambers 14, respectively, and can be easily manufactured in the same film forming process. .

  Furthermore, in the present embodiment, the thin vibration film 31 is formed by the AD method, but may be formed by a film forming method such as a method of forming from electroless plating or a method of vapor deposition such as CVD or PVD. . The vibration film 31 is not limited to stainless steel, and may be formed of any material such as ceramics as long as it does not melt in the annealing process.

  Further, the separation membrane 81 is not limited to lead, and may be formed of a metal material that melts at an annealing temperature such as aluminum or duralumin. Further, the material is not limited to a metal material, and may be formed of any material, such as ceramics or resin, as long as it has a hardness that can withstand film formation by the AD method. Furthermore, it is not limited to a material that melts at an annealing temperature such as lead, but may be a material that thermally decomposes in an annealing process, such as a resin. In addition, although the annealing temperature is 800 ° C., any temperature may be used as long as the annealing for improving the piezoelectric characteristics of the piezoelectric layer 32 is possible. In this case, the separation film 81 has a temperature higher than the annealing temperature. Any material that melts or thermally decomposes may be used.

  In addition, in the present embodiment, the separation film 81 is formed by the sputtering method, but may be formed by the AD method. In this case, the separation membrane forming process and the film forming process can be performed in the same chamber only by switching the aerosol chamber communicating with the spray nozzle 73. Moreover, you may form by other film-forming methods (sol-gel method, vapor deposition, etc.). Further, a plate member that melts in the annealing process may be attached to the stage 80, and the piezoelectric layer 32 and the vibration film 31 may be formed on the plate member.

  Further, the present invention is not limited to a method for manufacturing a piezoelectric actuator having a plurality of individual electrodes (active parts), such as a piezoelectric actuator that is bonded to a flow path unit and applies pressure to a liquid in a pressure chamber. It is also possible to apply the present invention to a method of manufacturing a piezoelectric actuator that has only one active part and is joined to a driving target having a predetermined moving part and drives the driving target.

  Furthermore, the present invention relates to a method for manufacturing a liquid transfer device that transfers liquid in a liquid transfer channel including a pressure chamber by applying pressure to the liquid in the pressure chamber, such as a liquid discharge head that discharges liquid other than ink from a nozzle. It is also possible to apply.

DESCRIPTION OF SYMBOLS 1 Inkjet head 4 Flow path unit 5 Piezoelectric actuator 31 Vibrating membrane 32 Piezoelectric layer 81 Separation membrane 100 Inkjet printer

Claims (7)

A film forming step of forming a vibration film and a piezoelectric layer on one surface of the substrate with a material having a melting point higher than the melting point or thermal decomposition temperature of the substrate;
After the film forming step, a removing step of removing the substrate by heating to a predetermined temperature lower than the melting point of the vibration film and the piezoelectric layer and higher than the melting point or thermal decomposition temperature of the substrate; A method of manufacturing a piezoelectric actuator comprising: In the film formation step, the piezoelectric layer is formed by an aerosol deposition method,
A heating step of heating the piezoelectric layer at the predetermined temperature at which the piezoelectric layer can be annealed after the film-forming step;
The method for manufacturing a piezoelectric actuator according to claim 1, wherein the heating step also serves as the removing step, and the base material is also heated to be removed. In the film forming step, the piezoelectric layer is formed by a sol-gel method,
A heating step of heating the piezoelectric layer at the predetermined temperature capable of removing the solvent in the gel after the film-forming step;
The method for manufacturing a piezoelectric actuator according to claim 1, wherein the heating step also serves as the removing step, and the base material is also heated to be removed.   In the film forming step, after the piezoelectric layer is formed on the one surface of the base material, the vibration film is formed on a surface of the piezoelectric layer opposite to the base material. Item 4. The method for manufacturing a piezoelectric actuator according to any one of Items 1 to 3. The base material is formed of a material containing lead,
5. The method of manufacturing a piezoelectric actuator according to claim 4, wherein in the film forming step, the piezoelectric layer is formed of a piezoelectric material containing lead on the one surface of the base material. A flow path unit in which a liquid flow path including a pressure chamber is formed; a vibration film disposed on the flow path unit so as to cover at least the pressure chamber; and a vibration film disposed on a side opposite to the pressure chamber. A method of manufacturing a liquid transfer device comprising a piezoelectric actuator including a piezoelectric layer,
A film forming step of forming a vibration film and a piezoelectric layer on one surface of the substrate with a material having a melting point higher than the melting point or thermal decomposition temperature of the substrate;
After the film forming step, a removing step of removing the substrate by heating at a predetermined temperature lower than the melting point of the vibration film and the piezoelectric layer and higher than the melting point or thermal decomposition temperature of the substrate;
After the removing step, the vibrating membrane and the vibrating membrane cover the pressure chamber so that the surface of the vibrating membrane opposite to the surface on which the piezoelectric layer is disposed is opposed to the flow path unit. And a joining step for joining the flow path units. The method of manufacturing a liquid transfer device according to claim 6, wherein, in the film forming step, the bonding step is performed after the piezoelectric layer is formed by an aerosol deposition method.

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