JP2009208411A - Method for manufacturing liquid injection head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a liquid injection head, having an improved yield. <P>SOLUTION: An insulator film 55 is formed on a temporary substrate 400 made of a material other than metal, and a piezoelectric layer 70 is formed on the insulator film 55. The piezoelectric layer 70 is patterned, and a lower electrode film 60 is formed on the piezoelectric layer 70. An elastic film 56 and a protective film 57 constituting a vibration plate are sequentially laminated on the lower electrode film 60. The temporary plate 400 is bonded to a flow path forming substrate 10 formed with a pressure generating chamber 12, in such manner that the piezoelectric layer 70 faces the pressure generating chamber 20 via the vibration plate. The temporary substrate 400 is removed to expose the insulator film 55, the area of the insulator film 55 facing the pressure generating chamber 12 is removed to form an opening, and an upper electrode film is formed which is connected to the exposed piezoelectric layer 70 via the opening. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a method for manufacturing a liquid ejecting head that ejects droplets from nozzles, and more particularly, to a method for manufacturing an ink jet recording head that ejects ink droplets as droplets.

  As a typical example of a liquid ejecting head, for example, a part of a pressure generation chamber communicating with a nozzle opening for ejecting ink droplets is configured by a vibration plate, and the vibration plate is deformed by a piezoelectric element so that ink in the pressure generation chamber is discharged. There are ink jet recording heads that pressurize and eject ink droplets from nozzle openings.

  As such a piezoelectric element, a piezoelectric material exhibiting an electromechanical conversion function, for example, a piezoelectric layer made of crystallized dielectric material lead zirconate titanate is sandwiched between two electrodes, a lower electrode and an upper electrode. There is something composed of.

  This piezoelectric layer (piezoelectric film) is formed as follows, for example. First, a first-layer piezoelectric precursor film is formed on the lower electrode by a sol-gel method, and the piezoelectric precursor film is fired and crystallized to form a piezoelectric film. Then, a piezoelectric layer having a predetermined thickness is formed by sequentially stacking the piezoelectric films (see, for example, Patent Document 1).

JP 2006-306709 A

  However, in the firing step for crystallizing the piezoelectric precursor film made of a ferroelectric material, the metal constituting the lower electrode diffuses into the piezoelectric layer on the lower electrode, thereby cracking the piezoelectric layer. And cracks may occur. For this reason, in the manufacture of an ink jet recording head, there is a problem that the yield decreases due to the occurrence of defects due to cracks and cracks generated in the piezoelectric layer.

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

  SUMMARY An advantage of some aspects of the invention is that it provides a method for manufacturing a liquid jet head capable of improving yield.

An aspect of the present invention that achieves the above object includes a flow path forming substrate in which a pressure generating chamber communicating with a nozzle opening for discharging a liquid is formed, and a vibration in a region facing the pressure generating chamber of the flow path forming substrate. A method of manufacturing a liquid jet head comprising a lower electrode, a piezoelectric layer, and a piezoelectric element comprising an upper electrode provided via a plate, wherein a ferroelectric material is formed on a temporary substrate made of a material other than metal. Forming a piezoelectric precursor film and performing a heat treatment step for crystallizing the piezoelectric precursor film to form a piezoelectric layer; patterning the piezoelectric layer into a predetermined shape; Forming a lower electrode on the piezoelectric layer, forming a diaphragm on the lower electrode; and patterning the piezoelectric layer on the flow path forming substrate on which the pressure generating chamber is formed. Through the pressure generation chamber The step of bonding the temporary substrate, the step of exposing the piezoelectric layer by removing the temporary substrate, and the step of forming an upper electrode on the exposed piezoelectric layer are provided. And a manufacturing method of the liquid jet head.
In this aspect, in the step of forming the piezoelectric layer, the piezoelectric layer is formed on the temporary substrate made of a material other than the metal, so that the metal diffuses into the piezoelectric layer and cracks and cracks are generated in the piezoelectric layer. Can be prevented. As a result, the yield of the liquid jet head can be improved.

  Here, prior to the step of forming the piezoelectric layer, a step of forming an insulator film on the temporary substrate is provided, and in the step of exposing the piezoelectric layer, the temporary substrate is removed by removing the temporary substrate. In the step of exposing the insulator film and forming the upper electrode, the exposed portion of the insulator film is removed from the region facing the piezoelectric layer to form an opening, and the opening exposed through the opening is formed. It is preferable to form an upper electrode connected to the piezoelectric layer. According to this, the upper electrode and the lower electrode constituting the piezoelectric layer can be reliably insulated by the insulator film.

  In the step of forming the insulator film, an insulator film made of zirconium oxide is preferably formed on the temporary substrate made of a silicon single crystal substrate. This prevents the components of the piezoelectric layer from diffusing into the silicon single crystal substrate in the piezoelectric layer forming step.

  In the step of forming the piezoelectric film, the piezoelectric film is preferably formed by baking the piezoelectric precursor film at 700 ° C. to 1000 ° C. According to this, a piezoelectric layer having the best piezoelectric characteristics can be formed. As a result, a liquid ejecting head having excellent liquid ejection characteristics can be manufactured.

  Further, in the step of forming the diaphragm, an elastic film is formed on the lower electrode, and a protective film having resistance to the liquid is formed on the elastic film, thereby removing the protective film and the elastic film. It is preferable to form a diaphragm. According to this, since the protective film having resistance to the liquid is formed, it is possible to prevent the elastic film from being eroded by the liquid in the pressure generating chamber.

  In the step of bonding the temporary substrate, it is preferable that the temporary substrate is bonded to the flow path forming substrate formed of a silicon single crystal substrate in which the pressure generation chamber and the nozzle opening are integrally formed. According to this, since the silicon single crystal substrate in which the pressure generating chamber and the nozzle opening are integrally formed in advance is used, the manufacturing process of the liquid jet head can be simplified.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is an exploded perspective view showing a schematic configuration of an ink jet recording head which is an example of a liquid ejecting head according to the present embodiment, and FIG. 2 is a plan view of FIG. 1 and a sectional view taken along line AA ′.

  As shown in these drawings, the flow path forming substrate 10 is composed of a silicon single crystal substrate whose crystal plane orientation in the plate thickness direction is the (110) plane in this embodiment. On the flow path forming substrate 10, a pressure generating chamber 12, a communication portion 13, an ink supply path 14, a communication path 15, and a nozzle opening 21 that form a liquid flow path are integrally formed. Specifically, by performing anisotropic etching from one side of the flow path forming substrate 10, the pressure generating chambers 12 partitioned by the plurality of partition walls 11 are arranged in parallel in the width direction (short direction). In the vicinity of the end of each pressure generating chamber 12 opposite to the ink supply path 14, a nozzle opening 21 that opens to the other surface of the flow path forming substrate 10 is provided. In addition, a communication portion 13 is formed in a region outside the longitudinal direction of the pressure generation chambers 12 in each row, and the communication portion 13 and each pressure generation chamber 12 are provided for each pressure generation chamber 12. The communication path 15 communicates with each other. That is, in the present embodiment, the pressure generation chamber 12, the communication part 13, the ink supply path 14, and the communication path 15 are formed as liquid flow paths in the flow path forming substrate 10.

  The communication portion 13 communicates with a reservoir portion 31 of the protective substrate 30 described later and constitutes a part of the reservoir 100 that becomes a common ink chamber for each row of the pressure generation chambers 12. The ink supply path 14 is formed with a narrower width than the pressure generation chamber 12, and maintains a constant flow path resistance of ink flowing into the pressure generation chamber 12 from the communication portion 13. In the present embodiment, the ink supply path 14 is formed by narrowing one of the widths of the pressure generation chamber 12 and the communication path 15, but is not particularly limited to this, for example, the pressure generation chamber 12 and the communication path 15. The ink supply path 14 may be formed by narrowing the width on both sides, or the ink supply path 14 may be formed by narrowing in the thickness direction.

On the other hand, a protective film 57, an elastic film 56, a lower electrode film 60, a piezoelectric layer 70, an upper electrode film, which are laminated in advance by a process described later, are formed on the surface of the flow path forming substrate 10 opposite to the nozzle openings 21. 80 and an insulator film 55 are provided. The protective film 57 is a film that is resistant to a liquid, for example, ink, and is used to prevent the substrate or film covered by the protective film 57 from being eroded by the liquid. An elastic film 56 made of silicon dioxide (SiO ₂ ) or the like is formed on the protective film 57. Further, a lower electrode film 60 patterned in a predetermined shape is formed on the elastic film 56, and titanic acid which is an example of a piezoelectric film is provided on the lower electrode film 60 so as to face each pressure generating chamber 12. A piezoelectric layer 70 made of lead zirconate (PZT) or the like is formed. Further, on the elastic film 56, the lower electrode film 60, and the piezoelectric layer 70, an insulating film 55 having an opening 55a is formed in a region facing each piezoelectric layer 70, and the piezoelectric film exposed to the opening 55a is formed. An upper electrode film 80 is formed on the body layer 70. Then, the surface of the flow path forming substrate 10 opposite to the nozzle opening 21 is bonded to the protective film 57 via the adhesive 16, so that the protective film 57, the elastic film 56, the lower electrode film 60, the piezoelectric body. The layer 70, the upper electrode film 80, and the insulator film 55 are fixed to the flow path forming substrate 10.

The protective film 57 is to prevent the elastic film 56 from being eroded by the ink in the pressure generation chamber 12. Specifically, the protective film 57 is made of aluminum oxide, but other than that, tantalum oxide is also used. It may consist of (TaO _x ) and this specific example is merely an exemplary listing. The insulator film 55 prevents a short circuit between the lower electrode film 60 and the upper electrode film 80.

  Here, the piezoelectric element 300 refers to a portion including the lower electrode film 60, the piezoelectric layer 70, and the upper electrode film 80. In general, one electrode of the piezoelectric element 300 is used as a common electrode, and the other electrode and the piezoelectric layer 70 are patterned for each pressure generating chamber 12. In the present embodiment, the lower electrode film 60 is used as a common electrode of the piezoelectric element 300 and the upper electrode film 80 is used as an individual electrode of the piezoelectric element 300. However, there is no problem even if this is reversed for convenience of a drive circuit and wiring.

  In addition, here, the piezoelectric element 300 and the diaphragm that is displaced by driving the piezoelectric element 300 are collectively referred to as an actuator device. In the example described above, the protective film 57 and the elastic film 56 function as a diaphragm.

The piezoelectric layer 70 is made of a piezoelectric material having an electromechanical conversion effect formed on the lower electrode film 60, particularly a ferroelectric material having a perovskite structure among the piezoelectric materials. The piezoelectric layer 70 is preferably a crystal film having a perovskite structure. For example, a ferroelectric material such as lead zirconate titanate (PZT) or a metal oxide such as niobium oxide, nickel oxide, or magnesium oxide is used. Those to which is added are suitable. Specifically, lead titanate (PbTiO ₃ ), lead zirconate titanate (Pb (Zr, Ti) O ₃ ), lead zirconate (PbZrO ₃ ), lead lanthanum titanate ((Pb, La), TiO ₃ ) ), Lead lanthanum zirconate titanate ((Pb, La) (Zr, Ti) O ₃ ) or lead magnesium titanate zirconate titanate (Pb (Zr, Ti) (Mg, Nb) O ₃ ), etc. However, it is added that the materials that are the subject of this issue are not limited to these materials.

  Further, each upper electrode film 80 that is an individual electrode of the piezoelectric element 300 is drawn from the vicinity of the end on the ink supply path 14 side and extended to the insulator film 55, for example, aluminum (Al) or the like. The lead electrode 90 which consists of is connected. The insulating film 55 is also provided with an opening 55b in a region facing a part of the lower electrode film 60, and the opening 55b is formed in a part of the lower electrode film 60 exposed to the opening 55b. A lead electrode 90 that is drawn out from the electrode and extends to the insulator film 55 is connected.

  On the flow path forming substrate 10 on which such a piezoelectric element 300 is formed, that is, on the insulator film 55 and the lead electrode 90, the protective substrate 30 having the reservoir portion 31 constituting at least a part of the reservoir 100 is bonded. It is joined via the agent 35. In the present embodiment, the reservoir portion 31 is formed through the protective substrate 30 in the thickness direction and across the width direction of the pressure generation chamber 12. As described above, the communication portion 13 of the flow path forming substrate 10. The reservoir 100 is configured as a common ink chamber for the pressure generation chambers 12. Alternatively, the communication portion 13 of the flow path forming substrate 10 may be divided into a plurality of pressure generation chambers 12 and only the reservoir portion 31 may be used as the reservoir. Further, for example, a member (for example, a protective film 57, an elastic film 56, an insulator film 55) provided between the flow path forming substrate 10 and the protective substrate 30 by providing only the pressure generating chamber 12 in the flow path forming substrate 10. An ink supply path 14 that communicates the reservoir and each pressure generating chamber 12 may be provided.

  The protective substrate 30 is provided with a piezoelectric element holding portion 32 having a space that does not hinder the movement of the piezoelectric element 300 in a region facing the piezoelectric element 300. In addition, the piezoelectric element holding part 32 should just have a space of the grade which does not inhibit the motion of the piezoelectric element 300, and the said space may be sealed or may not be sealed.

  The protective substrate 30 is provided with a through hole 33 that penetrates the protective substrate 30 in the thickness direction. The vicinity of the end portion of the lead electrode 90 drawn from each piezoelectric element 300 is provided so as to be exposed in the through hole 33.

  A drive circuit 120 for driving the piezoelectric elements 300 arranged in parallel is fixed on the protective substrate 30. 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 inserted through the through hole 33.

  As the protective substrate 30, it is preferable to use a material substantially the same as the coefficient of thermal expansion of the flow path forming substrate 10, for example, glass, a ceramic material, etc. In this embodiment, the surface orientation of the same material as the flow path forming substrate 10 is used. It was formed using a (110) silicon single crystal substrate.

  A compliance substrate 40 including a sealing film 41 and a fixing plate 42 is bonded onto the protective substrate 30. Here, the sealing film 41 is made of a material having low rigidity and flexibility, for example, a polyphenylene sulfide (PPS) film, and one surface of the reservoir portion 31 is sealed by the sealing film 41. The fixing plate 42 is made of a hard material such as metal, for example, stainless steel (SUS). Since the region of the fixing plate 42 facing the reservoir 100 is an opening 43 that is completely removed in the thickness direction, one surface of the reservoir 100 is sealed only with a flexible sealing film 41. Has been.

  In such an ink jet recording head of this embodiment, ink is taken in from an external ink supply means (not shown), filled with ink from the reservoir 100 to the nozzle opening 21, and then in accordance with a recording signal from the drive circuit 120. By applying a voltage between each of the lower electrode film 60 and the upper electrode film 80 corresponding to the pressure generation chamber 12 to bend and deform the protective film 57 and the elastic film 56, the pressure in each pressure generation chamber 12 is changed. Ink droplets are ejected from the nozzle opening 21.

  Here, a method of manufacturing the ink jet recording head will be described with reference to FIGS. 3 to 6 are cross-sectional views in the longitudinal direction of the pressure generating chamber showing the method of manufacturing the ink jet recording head.

First, as shown in FIG. 3A, an insulator film 55 made of zirconium oxide is formed on the surface of a temporary substrate 400 made of a silicon wafer. Specifically, after forming a zirconium (Zr) layer on the temporary substrate 400 by, for example, a sputtering method or the like, the zirconium film is thermally oxidized to form an insulator film 55 made of zirconium oxide (ZrO ₂ ). . By forming zirconium oxide, the components of the piezoelectric layer formed in the next step are prevented from diffusing into the temporary substrate 400.

  Next, as shown in FIG. 3B, a piezoelectric layer 70 is formed and patterned into a predetermined shape. Here, in this embodiment, a so-called sol in which an organometallic compound is dissolved and dispersed in a solvent is applied, dried, gelled, and further fired at a high temperature to obtain a piezoelectric layer 70 made of a metal oxide. The piezoelectric layer 70 is formed using a gel method. In addition, the manufacturing method of the piezoelectric layer 70 is not limited to the sol-gel method, for example, using a PVD (Physical Vapor Deposition) method such as a MOD (Metal-Organic Decomposition) method, a sputtering method, or a laser ablation method. Also good.

As a specific procedure for forming the piezoelectric layer 70 using the sol-gel method or the MOD method, first, a piezoelectric precursor film is formed on the insulator film 55. That is, a sol (solution) containing a ferroelectric material having a perovskite structure is applied on the insulator film 55 (application process). Next, the piezoelectric precursor film is heated to a predetermined temperature and dried for a predetermined time (drying step). Next, the dried piezoelectric precursor film is degreased by heating to a predetermined temperature and holding for a certain time (degreasing step). Here, degreasing refers, the organic components contained in the piezoelectric precursor film, for example, is to be detached as _{NO 2, CO 2, H 2} O or the like.

  Then, the piezoelectric precursor film is crystallized by heating to a predetermined temperature and holding for a predetermined time to form a first piezoelectric film (firing step). In the firing step of the present embodiment, the piezoelectric precursor film is fired at 700 ° C. to 1000 ° C. A firing temperature in this range can form a piezoelectric layer having the best piezoelectric characteristics. Thereafter, the application process, the drying process, the degreasing process, and the baking process are repeated a plurality of times to form the piezoelectric layer 70 having a desired thickness. In addition, as a heating apparatus used in such a drying process, a degreasing process, and a baking process, for example, a hot plate, an RTP (Rapid Thermal Processing) apparatus that heats by irradiation with an infrared lamp, or the like can be used.

  As described above, in the ink jet recording head manufacturing method according to the present invention, the piezoelectric layer 70 is formed on the temporary substrate 400 made of a material other than metal and not having the lower electrode film formed thereon. Metal does not diffuse from the electrode film into the piezoelectric layer. Thereby, it is possible to prevent the piezoelectric layer 70 from being cracked or cracked due to metal diffusion.

  Next, as shown in FIG. 3C, the lower electrode film 60 is formed on the insulator film 55 and the piezoelectric layer 70 by stacking, for example, platinum (Pt) and iridium (Ir). Thereafter, the lower electrode film 60 is patterned into a predetermined shape. The lower electrode film 60 can be formed by, for example, a sputtering method. The lower electrode film 60 is not limited to a laminate of platinum and iridium, and an alloy of these may be used. Further, the lower electrode film 60 may be used as a single layer of either platinum or iridium. Furthermore, metals or metal oxides other than these materials may be used. For example, titanium (Ti) can be used.

Next, as shown in FIG. 4A, the elastic film 56 and the protective film 57 are sequentially stacked on the lower electrode film 60. The elastic film 56 is made of, for example, silicon dioxide (SiO ₂ ) and can be formed by a CVD method. The protective film 57 is made of, for example, aluminum oxide (AlO _x ) and can be formed by a CVD method, a sputtering method, or the like. The protective film 57 only needs to be formed of a material that is resistant to the ink in the pressure generating chamber 12, and may be tantalum oxide (TaO _x ).

  Next, a flow path formed of a silicon single crystal substrate in which the pressure generation chamber 12, the ink supply path 14, the communication path 15, the communication section 13, and the nozzle opening 21 constituting the fluid flow path are integrally formed in advance is formed. The substrate wafer 110 and the temporary substrate 400 are bonded.

  More specifically, as shown in FIG. 4B, the piezoelectric layer 70 formed on the temporary substrate 400 is opposed to the pressure generating chamber 12 provided on one side of the flow path forming substrate wafer 110. 4C, the flow path forming substrate wafer 110 is bonded to the protective film 57 side of the temporary substrate 400 via the adhesive 16. As shown in FIG. As a result, the piezoelectric layer 70 is disposed opposite to the pressure generating chamber 12 via the protective film 57 and the elastic film 56 (vibrating plate). At this time, the region of the protective film 57 facing the piezoelectric layer 70 protrudes closer to the pressure generating chamber 12 than the upper surface of the flow path forming substrate 10 on the protective film 57 side.

  Next, as shown in FIG. 5A, the temporary substrate 400 is removed. For example, the temporary substrate 400 is removed by performing wet etching using a KOH solution. Thereby, the insulator film 55 is exposed.

  Next, as shown in FIG. 5B, a mask pattern (not shown) such as a resist having a predetermined shape is formed on the insulator film 55, and a region of the insulator film 55 facing the piezoelectric layer 70 is formed. Remove by dry etching. By this dry etching, an opening 55a is formed in the insulator film 55, and the piezoelectric layer 70 is exposed in the opening 55a. At this time, a region facing a part of the lower electrode film 60 is also removed by dry etching. By this dry etching, an opening 55b is formed in the insulator film 55, and a part of the lower electrode film 60 is exposed in the opening 55b.

  Next, as shown in FIG. 5C, an upper electrode film 80 made of, for example, iridium (Ir) is formed on the piezoelectric layer 70 exposed in the opening 55a by a sputtering method, and the lower electrode film 60, A piezoelectric element 300 including the piezoelectric layer 70 and the upper electrode film 80 is formed. The upper electrode film 80 is not limited to iridium, and, for example, titanium (Ti) can be used.

  Next, as shown in FIG. 6A, lead electrodes 90 are formed. Specifically, an aluminum film is formed over the entire surface of the flow path forming substrate wafer 110 by, for example, sputtering, and thereafter, for each piezoelectric element 300 through a mask pattern (not shown) made of, for example, a resist or the like. It is formed by patterning. At this time, patterning is performed so that the lead electrode 90 extends from the lower electrode film 60 exposed in the opening 55b. The lead electrode 90 is not limited to aluminum, and may be nickel, chromium, gold, copper, platinum, or iridium, or may be a plurality of types of metals.

  Next, as shown in FIG. 6B, the protective substrate wafer 130 is bonded onto the flow path forming substrate wafer 110 via an adhesive 35. Here, the protective substrate wafer 130 is formed by integrally forming a plurality of protective substrates 30, and a reservoir portion 31 and a piezoelectric element holding portion 32 are formed in advance on the protective substrate wafer 130.

  Thereafter, the protective film 57, the elastic film 56, and the insulator film 55 interposed between the communication portion 13 of the flow path forming substrate 10 and the reservoir portion 31 of the protective substrate wafer 130 are removed to form the reservoir 100. Further, unnecessary portions of the outer peripheral edge portions of the flow path forming substrate wafer 110 and the protective substrate wafer 130 are removed by cutting, for example, by dicing. The compliance substrate 40 is bonded to the protective substrate wafer 130, and the flow path forming substrate wafer 110 or the like is divided into a single chip size flow path forming substrate 10 or the like as shown in FIG. A recording head is used.

  As described above, according to the method of manufacturing the ink jet recording head according to the present embodiment, in the heat treatment step for crystallizing the piezoelectric layer 70, the piezoelectric body is formed on the temporary substrate 400 made of a material other than metal. Since the layer 70 is formed, it is possible to prevent cracks and cracks from being generated in the piezoelectric layer 70 due to the metal diffusing into the piezoelectric layer 70. Thereby, the yield of the ink jet recording head can be improved.

  In the ink jet recording head manufacturing method according to the present embodiment, the piezoelectric layer is formed on the insulator film, not on the metal such as the lower electrode film, at a firing temperature of 700 ° C. to 1000 ° C. A piezoelectric layer having the best piezoelectric characteristics can be formed without deteriorating the piezoelectric characteristics by diffusion. Thereby, an ink jet recording head excellent in ink ejection characteristics can be manufactured.

  Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment. In the above-described embodiment, after the insulator film 55 is formed on the temporary substrate 400, the piezoelectric layer 70 is formed on the insulator film 55. However, the present invention is not limited to this. For example, an insulator film may be formed before forming the upper electrode film on the piezoelectric layer. That is, first, a piezoelectric layer is formed on a temporary substrate and patterned into a predetermined shape, a lower electrode film and a diaphragm are sequentially stacked on the piezoelectric layer, and the temporary substrate is bonded to the flow path forming substrate. The insulating film is formed on the piezoelectric layer exposed by removing the temporary substrate, the region facing the piezoelectric layer of the insulating film is removed to form the opening, and the piezoelectric exposed to the opening An upper electrode film connected to the body layer may be formed. Furthermore, if the lower electrode film and the upper electrode film are appropriately patterned so that the lower electrode film and the upper electrode film are not short-circuited, it is not always necessary to provide the insulator film.

  In addition, for example, a silicon single crystal substrate is exemplified as the flow path forming substrate, but the present invention is not particularly limited thereto, and the present invention is also effective in, for example, an SOI substrate, a glass substrate, an MgO substrate, and the like. Similarly, although a silicon single crystal substrate has been exemplified as the protective substrate wafer, the present invention is not particularly limited thereto, and may be, for example, an SOI substrate, a glass substrate, an MgO substrate, or the like.

  Further, in the above-described embodiment, the flow path forming substrate 10 includes the pressure generating chamber 12, the communication portion 13, the ink supply path 14, the communication path 15, and the nozzle opening 21, which are liquid flow paths, as a single silicon single crystal. Although formed on the substrate, these may be formed on separate members. For example, a nozzle plate provided with a nozzle opening communicating with the pressure generation chamber may be joined to one surface of a flow path forming substrate provided with a liquid flow path such as a pressure generation chamber.

  In the above-described embodiment, the ink jet recording head has been described as an example of the liquid ejecting head. However, the present invention is widely applied to all liquid ejecting heads, and the liquid ejecting ejects a liquid other than ink. Of course, the present invention can also be applied to a head manufacturing method. Other liquid ejecting heads include, for example, various recording heads used in image recording apparatuses such as printers, color material ejecting heads used in the manufacture of color filters such as liquid crystal displays, organic EL displays, and FEDs (field emission displays). Examples thereof include an electrode material ejection head used for electrode formation, a bioorganic matter ejection head used for biochip production, and the like.

FIG. 2 is an exploded perspective view illustrating a schematic configuration of a recording head according to an embodiment. 2A and 2B are a plan view and a cross-sectional view of the recording head according to the embodiment. FIG. 6 is a cross-sectional view illustrating a method for manufacturing a recording head according to an embodiment. FIG. 6 is a cross-sectional view illustrating a method for manufacturing a recording head according to an embodiment. FIG. 6 is a cross-sectional view illustrating a method for manufacturing a recording head according to an embodiment. FIG. 6 is a cross-sectional view illustrating a method for manufacturing a recording head according to an embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Flow path formation board | substrate, 12 Pressure generating chamber, 21 Nozzle opening, 30 Protection board | substrate, 55 Insulator film | membrane, 56 Elastic film | membrane, 57 Protective film | membrane, 60 Lower electrode film | membrane, 70 Piezoelectric layer, 80 Upper electrode film | membrane, 90 Lead electrode , 120 drive circuit, 300 piezoelectric element, 400 temporary substrate

Claims (6)

A flow path forming substrate in which a pressure generating chamber communicating with a nozzle opening for discharging a liquid is formed; a lower electrode provided in a region opposite to the pressure generating chamber of the flow path forming substrate through a vibration plate; A method of manufacturing a liquid jet head comprising a piezoelectric element including a body layer and an upper electrode,
Forming a piezoelectric precursor film made of a ferroelectric material on a temporary substrate made of a material other than a metal and forming a piezoelectric layer by performing a heat treatment step for crystallizing the piezoelectric precursor film; When,
Patterning the piezoelectric layer into a predetermined shape;
Forming a lower electrode on the piezoelectric layer, and forming a diaphragm on the lower electrode;
Bonding the temporary substrate to the flow path forming substrate in which the pressure generating chamber is formed so that the patterned piezoelectric layer faces the pressure generating chamber via the vibration plate;
Exposing the piezoelectric layer by removing the temporary substrate;
And a process of forming an upper electrode on the exposed piezoelectric layer. The method of manufacturing a liquid jet head according to claim 1,
Before the step of forming the piezoelectric layer, comprising the step of forming an insulator film on the temporary substrate,
In the step of exposing the piezoelectric layer, the insulator film is exposed by removing the temporary substrate,
In the step of forming the upper electrode, the exposed region of the insulating film facing the piezoelectric layer is removed to form an opening, and the upper electrode is connected to the exposed piezoelectric layer through the opening. A method of manufacturing a liquid jet head, comprising forming an electrode. In the manufacturing method of the liquid jet head according to claim 2,
In the step of forming the insulator film, the insulator film made of zirconium oxide is formed on the temporary substrate made of a silicon single crystal substrate. In the manufacturing method of the liquid jet head according to any one of claims 1 to 3,
In the step of forming the piezoelectric film, the piezoelectric film is formed by baking the piezoelectric precursor film at 700 ° C. to 1000 ° C. In the manufacturing method of the liquid jet head according to any one of claims 1 to 4,
In the step of forming the vibration plate, an elastic film is formed on the lower electrode, and a protective film having resistance to the liquid is formed on the elastic film, whereby the vibration composed of the protective film and the elastic film is formed. A method of manufacturing a liquid jet head, comprising forming a plate. In the manufacturing method of the liquid jet head according to any one of claims 1 to 5,
In the step of bonding the temporary substrate, the temporary substrate is bonded to the flow path forming substrate made of a silicon single crystal substrate in which the pressure generation chamber and the nozzle opening are integrally formed. Manufacturing method of the head.

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