JP2006272913A - Liquid injection head, its manufacturing method, and liquid injection apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid injection head which surely prevents a discharge failure such as clogging of a nozzle with foreign matters, and is provided with a flow path forming substrate and a reservoir forming substrate well joined to each other, and also to provide manufacturing method thereof. <P>SOLUTION: The liquid injection head is provided with: the flow path forming substrate 10 where a pressure chamber 12 communicating with a nozzle opening to discharge a liquid droplet is formed; a piezoelectric element 300 consisting of a lower electrode 60, a piezoelectric body layer 70 and an upper electrode 80, which are provided on one surface of the flow path forming substrate 10 through an oscillating plate; and the reservoir forming substrate 30 which is joined to the flow path forming substrate 10 with an adhesive 35 and has a reservoir part 31. The head also has a joining layer 98 consisting of an oxidized metal at least in a part of joining area of the flow path forming substrate 10 with the reservoir forming substrate 30 so that the reservoir forming substrate 30 is joined on the joining layer 98. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  More particularly, the present invention relates to an ink jet recording head that ejects ink as a liquid, a manufacturing method thereof, and an ink jet recording apparatus.

  As an ink jet recording head that is a liquid ejecting head, for example, a flow path forming substrate in which a pressure generation chamber communicating with a nozzle opening and a communication portion communicating with the pressure generation chamber are formed, and one of the flow path forming substrates is provided. Some include a piezoelectric element formed on the surface side, and a reservoir forming substrate having a reservoir portion that is joined to the surface of the flow path forming substrate on the piezoelectric element side and forms a part of the reservoir together with the communication portion (for example, Patent Document 1).

  In the head having such a configuration, the flow path forming substrate and the reservoir forming substrate are generally bonded to each other with an adhesive, and the wiring of the piezoelectric element is formed on the surface of the flow path forming substrate. Therefore, the adhesiveness of the adhesive to the flow path forming substrate is relatively low. For this reason, there is a possibility that the ink in the reservoir oozes out from the adhesive portion and the piezoelectric element is destroyed by the moisture of the oozed ink.

  Further, in such a configuration in which the flow path forming substrate and the reservoir forming substrate are joined, for example, a diaphragm is mechanically punched to form a through portion, and the reservoir portion and the communication portion are connected via the through portion. Communicate. However, when the penetrating portion is formed by such mechanical processing, there is a problem that foreign matter such as machining residue is generated and the foreign matter enters a flow path such as a pressure generating chamber, which causes discharge failure and the like. In addition, after forming the penetration part, for example, by performing cleaning or the like, foreign matters such as processing residue can be removed to some extent, but it is difficult to remove completely. Further, when the penetrating portion is mechanically processed, a crack or the like is generated around the penetrating portion, and there is a problem that a discharge failure occurs due to the occurrence of the crack. That is, when ink is filled in a cracked state and discharged from the nozzle opening, there is a problem in that a broken piece falls off from the cracked portion, and the broken piece is clogged in the nozzle opening to cause a discharge failure.

  Such a problem exists not only in a method for manufacturing an ink jet recording head that discharges ink, but also in a method for manufacturing another liquid ejecting head that discharges liquid other than ink.

JP 2003-159801 A (FIGS. 7-8)

  In view of such circumstances, the present invention is capable of reliably preventing a discharge failure such as nozzle clogging due to a foreign substance and capable of satisfactorily joining a flow path forming substrate and a reservoir forming substrate, and a liquid ejecting head therefor It is an object to provide a manufacturing method.

According to a first aspect of the present invention for solving the above-described problem, a flow path forming substrate in which a pressure generating chamber communicating with a nozzle opening for discharging droplets is formed, and a diaphragm is provided on one side of the flow path forming substrate. And a piezoelectric element composed of a lower electrode, a piezoelectric layer and an upper electrode, and a reservoir which is bonded to the flow path forming substrate by an adhesive and forms a part of a reservoir which is a common liquid chamber of each pressure generating chamber A reservoir forming substrate provided with a portion, and having a bonding layer made of an oxidizing metal in at least a part of a bonding region of the flow path forming substrate with the reservoir forming substrate. The liquid ejecting head is bonded onto the bonding layer.
In the first aspect, since the bonding layer is interposed in the bonding region between the flow path forming substrate and the reservoir forming substrate, both substrates can be bonded satisfactorily. Therefore, it is possible to prevent the occurrence of defects due to the liquid oozing out from the adhesive portion, such as destruction of the piezoelectric element.

According to a second aspect of the present invention, in the first aspect, the communication part in which the flow path forming substrate communicates with the reservoir part via a through part provided in the diaphragm and forms a part of the reservoir. In the liquid jet head, the bonding layer is provided in at least a partial region around the penetrating portion.
In the second aspect, since the flow path forming substrate and the reservoir forming substrate are firmly bonded at the peripheral portion of the reservoir, it is possible to more reliably prevent the liquid in the reservoir from seeping out from the adhesive portion. it can.

According to a third aspect of the present invention, in the first or second aspect, the adhesive layer and the metal layer are included, the lead electrode is drawn out from the piezoelectric element, and the bonding layer is the adhesive layer. In the liquid jet head.
In the third aspect, since the bonding layer can be formed at the same time when the lead electrode is formed, the manufacturing process is not complicated, and the manufacturing cost does not increase.

A fourth aspect of the present invention is the alloy according to any one of the first to third aspects, wherein the bonding layer includes at least one selected from the group consisting of nickel, chromium, tin, aluminum, tantalum, titanium, and tungsten. The liquid ejecting head is characterized by comprising:
In the fourth embodiment, the adhesive layer is satisfactorily adhered by forming the bonding layer with a predetermined material. Therefore, the flow path forming substrate and the reservoir forming substrate can be bonded more firmly.

According to a fifth aspect of the present invention, in the liquid jet head according to any one of the first to fourth aspects, the adhesive is made of a material containing at least one of epoxy, silicone, or polyimide. is there.
In the fifth aspect, by using an adhesive made of a predetermined material, the flow path forming substrate and the reservoir forming substrate can be bonded more satisfactorily.

According to a sixth aspect of the invention, there is provided a liquid ejecting apparatus including the liquid ejecting head according to any one of the first to fifth aspects.
In the sixth aspect. A liquid ejecting head excellent in durability and reliability can be realized.

According to a seventh aspect of the present invention, a pressure generating chamber that communicates with a nozzle opening that ejects liquid and a communication portion that communicates with the pressure generating chamber are formed on one side of a flow path forming substrate via a diaphragm. Forming a piezoelectric element including a lower electrode, a piezoelectric layer, and an upper electrode and removing the diaphragm in the region serving as the communication portion to form a through portion; an adhesion layer made of an oxidizing metal; and the adhesion layer The lead electrode is formed of a metal layer formed thereon and is drawn out from the piezoelectric element, and the penetrating portion is sealed by a discontinuous metal layer which is composed of the adhesion layer and the metal layer but is discontinuous with the lead electrode. And a step of removing a part of the metal layer constituting the discontinuous metal layer to expose a part of the adhesion layer, and a reservoir part forming a part of the reservoir communicating with the communication part. The formed reservoir forming substrate Joining the exposed region of the formation substrate to the exposed region including the adhesion layer with an adhesive, and wet-etching the flow passage formation substrate from the other side until the vibration plate and the metal layer are exposed to form the pressure generating chamber. And a step of forming the communication portion, and a step of removing the discontinuous metal layer in a region corresponding to the penetrating portion by wet etching to cause the reservoir portion and the communication portion to communicate with each other. A method of manufacturing a liquid jet head.
In the seventh aspect, since an adhesive layer made of an oxidizing metal is interposed between the flow path forming substrate and the reservoir forming substrate, the adhesiveness of the adhesive is improved, and both substrates are bonded well and firmly. be able to. Further, when forming the reservoir, foreign matter such as machining residue is not generated, so that ejection failure such as nozzle clogging due to machining residue or the like is reliably prevented.

Hereinafter, the present invention will be described in detail based on embodiments.
(Embodiment 1)
1 is an exploded perspective view showing an ink jet recording head manufactured by a manufacturing method according to Embodiment 1 of the present invention, and FIG. 2 is a plan view and a cross-sectional view of FIG. As shown in the figure, the flow path forming substrate 10 is formed of a silicon single crystal substrate having a plane orientation (110) in this embodiment, and one surface thereof is previously formed of silicon dioxide by thermal oxidation and has a thickness of 1 to 2 μm. A film 50 is formed.

  A plurality of pressure generating chambers 12 are arranged in parallel in the width direction of the flow path forming substrate 10. Further, a communication portion 13 is formed in a region outside the longitudinal direction of the pressure generation chamber 12 of the flow path forming substrate 10, and the communication portion 13 and each pressure generation chamber 12 are provided for each pressure generation chamber 12. Communication is made via a path 14. The communication part 13 communicates with a reservoir part 31 of a reservoir forming substrate 30 to be described later and constitutes a part of the reservoir 100 serving as a common ink chamber for each pressure generating chamber 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.

Further, on the opening surface side of the flow path forming substrate 10, a nozzle plate 20 having a nozzle opening 21 communicating with the vicinity of the end portion of each pressure generating chamber 12 on the side opposite to the ink supply path 14 is used to generate pressure. The chamber 12 is fixed by an adhesive, a heat welding film or the like through a mask film 51 used as a mask when forming the chamber 12. The nozzle plate 20 has a thickness of, for example, 0.01 to 1 mm, a linear expansion coefficient of 300 ° C. or less, for example, 2.5 to 4.5 [× 10 ⁻⁶ / ° C.], glass ceramics, silicon It consists of a single crystal substrate or stainless steel.

  On the other hand, as described above, the elastic film 50 having a thickness of, for example, about 1.0 μm is formed on the side opposite to the opening surface of the flow path forming substrate 10. For example, an insulator film 55 having a thickness of about 0.4 μm is formed. Further, on the insulator film 55, a lower electrode film 60 having a thickness of, for example, about 0.2 μm, a piezoelectric layer 70 having a thickness of, for example, about 1.0 μm, and a thickness of, for example, about 0 The upper electrode film 80 having a thickness of 0.05 μm is laminated by a process described later to constitute the piezoelectric element 300. 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 addition, here, a portion that is configured by any one of the patterned electrodes and the piezoelectric layer 70 and in which piezoelectric distortion is generated by applying a voltage to both electrodes is referred to as a piezoelectric active portion. In this embodiment, the lower electrode film 60 is a common electrode of the piezoelectric element 300, and the upper electrode film 80 is an individual electrode of the piezoelectric element 300. However, there is no problem even if this is reversed for the convenience of the drive circuit and wiring. In either case, a piezoelectric active part is formed for each pressure generating chamber. Further, here, the piezoelectric element 300 and the vibration plate that is displaced by driving the piezoelectric element 300 are collectively referred to as a piezoelectric actuator.

  In addition, a lead electrode 90 is connected to the upper electrode film 80 of each piezoelectric element 300, and a voltage is selectively applied to each piezoelectric element 300 via the lead electrode 90. ing. The lead electrode 90 includes an adhesion layer 91 made of nickel chrome (NiCr) and a metal layer 92 formed on the adhesion layer 91 and made of, for example, gold (Au). In addition, the elastic film 50 and the insulator film 55 in the region corresponding to the peripheral edge of the opening of the communication portion 13 are also composed of the adhesion layer 91 and the metal layer 92 constituting the lead electrode 90, but are discontinuous with the lead electrode 90. The discontinuous metal layer 95 remains. Further, a part of the metal layer 92 constituting the discontinuous metal layer 95, for example, the peripheral edge of the discontinuous metal layer 95 is removed, and the lower adhesion layer 91 is exposed.

  A reservoir forming substrate 30 having a reservoir portion 31 constituting at least a part of the reservoir 100 is bonded to the surface of the flow path forming substrate 10 on the piezoelectric element 300 side by an adhesive 35. The reservoir portion 31 of the reservoir forming substrate 30 communicates with the communication portion 13 via a through portion 53 provided in the vibration plate, in this embodiment, the elastic film 50 and the insulator film 55. A reservoir 100 is formed by the portion 13.

  In addition, a piezoelectric element holding portion 32 is provided in a region facing the piezoelectric element 300 of the reservoir forming substrate 30. 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 reservoir forming substrate 30 include glass, ceramic material, metal, resin, and the like, but it is preferable that the reservoir forming substrate 30 be 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.

  Here, a bonding layer 98 made of an oxidizing metal is formed in a part of the bonding region of the flow path forming substrate 10 to which the reservoir forming substrate 30 is bonded by the adhesive 35. Since the bonding layer 98 made of an oxidizing metal has good adhesion to the adhesive 35, the flow path forming substrate 10 and the reservoir forming substrate 30 are bonded by the adhesive 35 with the bonding layer 98 interposed. Both substrates can be bonded well and firmly.

  The bonding layer 98 can increase the adhesive strength between the two substrates as long as the bonding layer 98 is provided in any position as long as it is a bonding region where the flow path forming substrate 10 and the reservoir forming substrate 30 are bonded. It is preferable that it is formed in the periphery of the through portion 53 that connects the communication portion 13 and the reservoir portion 31. Further, it is desirable that the peripheral portion of the penetrating portion 53 be provided particularly in a region between the reservoir 100 and the piezoelectric element holding portion 32. The oxidizing metal constituting the bonding layer 98 is not particularly limited, but is preferably an alloy containing at least one selected from the group consisting of nickel, chromium, tin, aluminum, tantalum, titanium, or tungsten, for example. .

  For example, in the present embodiment, the exposed adhesion layer 91 of the discontinuous metal layer 95 remaining over the peripheral edge of the through portion 53 also serves as the bonding layer 98. As described above, the adhesion layer 91 is made of, for example, nickel chrome (NiCr), and a portion of the upper metal layer 92 that is exposed by being removed functions as the bonding layer 98. The reservoir forming substrate 30 is bonded to the adhesion layer 91 as the bonding layer 98 by the adhesive 35. The type of the adhesive 35 for joining the reservoir forming substrate 30 and the flow path forming substrate 10 is not particularly limited, but is made of a material containing at least one of epoxy, silicone, or polyimide. Is preferred.

  In such a configuration, the flow path forming substrate 10 and the reservoir forming substrate 30 are satisfactorily bonded to increase the bonding strength, so that the ink in the reservoir 100 oozes out from the portion of the adhesive 35 and, for example, holds the piezoelectric element. Intrusion into the portion 32 and the like can be prevented. Therefore, it is possible to reliably prevent defects due to the exuded ink, for example, destruction of the piezoelectric element 300.

  A connection wiring 200 formed in a predetermined pattern is provided on the reservoir forming substrate 30, and a driving IC 210 for driving the piezoelectric element 300 is mounted on the connection wiring 200. Then, the leading end portion of each lead electrode 90 drawn from each piezoelectric element 300 to the outside of the piezoelectric element holding portion 32 and the driving IC 210 are electrically connected via the driving wiring 220.

  Furthermore, a compliance substrate 40 including a sealing film 41 and a fixing plate 42 is bonded onto a region corresponding to the reservoir portion 31 of the reservoir forming 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). The sealing film 41 seals one surface of the reservoir unit 31. 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 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 according to this embodiment, ink is taken in from an external ink supply unit (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 IC 210. 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 piezoelectric element 300 and the diaphragm, the pressure in each pressure generation chamber 12 is changed. Ink is ejected from the nozzle opening 21.

  Hereinafter, a method for manufacturing such an ink jet recording head will be described with reference to FIGS. 3 to 5 are cross-sectional views of the pressure generating chamber 12 in the longitudinal direction. First, as shown in FIG. 3A, a flow path forming substrate wafer 110, which is a silicon wafer, is thermally oxidized in a diffusion furnace at about 1100 ° C., and a silicon dioxide film 52 constituting an elastic film 50 is formed on the surface thereof. To do. In this embodiment, a silicon wafer having a relatively thick film thickness of about 625 μm and a high rigidity is used as the flow path forming substrate wafer 110.

Next, as shown in FIG. 3B, an insulator film 55 made of zirconium oxide is formed on the elastic film 50 (silicon dioxide film 52). Specifically, after a zirconium (Zr) layer is formed on the elastic film 50 (silicon dioxide film 52) by, for example, sputtering, the zirconium layer is thermally oxidized in a diffusion furnace at 500 to 1200 ° C., for example. Thus, the insulator film 55 made of zirconium oxide (ZrO ₂ ) is formed.

  Next, as shown in FIG. 3C, after the lower electrode film 60 is formed by stacking platinum and iridium on the insulator film 55, for example, the lower electrode film 60 is patterned into a predetermined shape. Next, as shown in FIG. 3 (d), a piezoelectric layer 70 made of, for example, lead zirconate titanate (PZT) and an upper electrode film 80 made of, for example, iridium are connected to a wafer 110 for flow path forming substrate. The piezoelectric element 300 is formed by patterning the piezoelectric layer 70 and the upper electrode film 80 in regions facing the pressure generation chambers 12. Further, the insulator film 55 and the elastic film 50 constituting the diaphragm are sequentially patterned, and the elastic film 50 and the insulator film are formed in a region where a communication portion (not shown) of the flow path forming substrate wafer 110 is formed. A penetrating portion 53 penetrating 55 is formed. Of course, the through portion 53 may be formed before the piezoelectric element 300 is formed.

Here, as a material of the piezoelectric layer 70 constituting the piezoelectric element 300, for example, a ferroelectric piezoelectric material such as lead zirconate titanate (PZT), niobium, nickel, magnesium, bismuth, yttrium or the like is used. A relaxor ferroelectric or the like to which any of these metals is added is preferably used. The composition may be appropriately selected in consideration of the characteristics, application, etc. of the piezoelectric element 300. For example, PbTiO ₃ (PT), PbZrO ₃ (PZ), Pb (Zr _x Ti _1-x ) O ₃ (PZT) ), Pb (Mg _1/3 Nb _2/3 ) O ₃ -PbTiO ₃ (PMN-PT), Pb (Zn _1/3 Nb _2/3 ) O ₃ -PbTiO ₃ (PZN-PT), Pb (Ni ₁ ) _{/ 3 Nb 2/3) O 3 -PbTiO} 3 (PNN-PT), Pb (In 1/2 Nb 1/2) O 3 -PbTiO 3 (PIN-PT), Pb (Sc 1/3 Ta 2/3 ) O ₃ —PbTiO ₃ (PST-PT), Pb (Sc _1/3 Nb _2/3 ) O ₃ —PbTiO ₃ (PSN-PT), BiScO ₃ —PbTiO ₃ (BS-PT), BiYbO ₃ —PbTiO ₃ (BY PT), and the like. The method for forming the piezoelectric layer 70 is not particularly limited. For example, in this embodiment, a so-called sol in which a metal organic substance is dissolved and dispersed in a catalyst is applied, dried, gelled, and further fired at a high temperature. The piezoelectric layer 70 was formed by using a so-called sol-gel method for obtaining a piezoelectric layer 70 made of an oxide.

  Next, as shown in FIG. 4A, a lead electrode 90 is formed. Specifically, first, an adhesion layer 91 made of nickel chromium (NiCr) is formed over the entire surface of the flow path forming substrate wafer 110, and a metal layer made of, for example, gold (Au) is formed on the adhesion layer 91. 92 is formed. Then, a mask pattern (not shown) made of, for example, a resist is formed on the metal layer 92, and the metal layer 92 and the adhesion layer 91 are patterned for each piezoelectric element 300 through the mask pattern, thereby leading to the lead electrode. 90 is formed.

  At this time, the adhesion layer 91 and the metal layer 92 in the region corresponding to the through portion 53 are left discontinuous with the lead electrode 90. That is, a discontinuous metal layer 95 composed of an adhesion layer 91 and a metal layer 92 discontinuous with the lead electrode 90 is formed in a region facing the penetrating portion 53, and the penetrating portion 53 is sealed with the discontinuous metal layer 95. To do. Further, a part of the metal layer 92 constituting the discontinuous metal layer 95 is removed, and a part of the adhesion layer 91 which is a lower layer is exposed. Such a discontinuous metal layer 95 plays a role in regulating the spread of etching when the pressure generating chamber 12 and the like are formed by etching the flow path forming substrate wafer 110 in a process described later. The exposed adhesion layer 91 also serves as the bonding layer 98, and also serves to improve the adhesion between the flow path forming substrate wafer 110 and the reservoir forming substrate wafer 130 to be bonded in the next step.

  Next, as illustrated in FIG. 4B, the reservoir forming substrate wafer 130 is bonded onto the flow path forming substrate wafer 110 by the adhesive 35. At this time, the reservoir forming substrate wafer 130 is bonded to the region including the bonding layer 98 formed on the flow path forming substrate wafer 110 by the adhesive 35. Thereby, the flow path forming substrate wafer 110 and the reservoir forming substrate wafer 130 are bonded very well. The reservoir forming substrate wafer 130 is preliminarily formed with a reservoir portion 31, a piezoelectric element holding portion 32, and the like, and the above-described connection wiring 200 is preliminarily formed on the reservoir forming substrate wafer 130. The reservoir forming substrate wafer 130 is, for example, a silicon wafer having a thickness of about 400 μm, and the rigidity of the flow path forming substrate wafer 110 is significantly improved by bonding the reservoir forming substrate wafer 130. Become.

  Next, as shown in FIG. 4C, after the flow path forming substrate wafer 110 is polished to a certain thickness, the flow path forming substrate wafer 110 is further etched by wet etching with hydrofluoric acid or the like. Make it thick. For example, in this embodiment, the flow path forming substrate wafer 110 is processed to have a thickness of about 70 μm by polishing and wet etching. Next, as shown in FIG. 5A, a mask film 51 made of, for example, silicon nitride (SiN) is newly formed on the flow path forming substrate wafer 110 and patterned into a predetermined shape. Then, as shown in FIG. 5B, the flow path forming substrate wafer 110 is anisotropically etched (wet etching) through the mask film 51, and the pressure generating chamber 12 is applied to the flow path forming substrate wafer 110. The communication part 13 and the ink supply path 14 are formed. Specifically, the pressure generation chamber 12 is etched by etching the flow path forming substrate wafer 110 with an etchant such as an aqueous potassium hydroxide (KOH) solution until the elastic film 50 and the discontinuous metal layer 95 are exposed. The communication part 13 and the ink supply path 14 are formed simultaneously.

  At this time, since the through portion 53 is sealed by the discontinuous metal layer 95, the etching liquid does not flow into the reservoir forming substrate wafer 130 via the through portion 53. As a result, the etching solution does not adhere to the connection wiring 200 provided on the surface of the reservoir forming substrate wafer 130, and the occurrence of defects such as disconnection can be prevented. Further, there is no possibility that the etching solution enters the reservoir portion 31 and the reservoir forming substrate wafer 130 is etched.

  When forming such a pressure generating chamber 12 or the like, the surface of the reservoir forming substrate wafer 130 opposite to the flow path forming substrate wafer 110 side is made of a material having alkali resistance, such as PPS (polyphenylene sulfide). ), PPTA (polyparaphenylene terephthalamide) or the like may be further sealed. Thereby, defects such as disconnection of wiring provided on the surface of the reservoir forming substrate wafer 130 can be more reliably prevented.

  Next, as shown in FIG. 5C, the discontinuous metal layer 95 in the region facing the through portion 53, that is, the adhesion layer 91 and the metal layer 92 is removed by wet etching, and the opened through portion 53 is removed. The reservoir 100 is formed by communicating the communication portion 13 and the reservoir portion 31 through the via. At this time, since the discontinuous metal layer 95 in the bonding region between the reservoir forming substrate wafer 130 and the flow path forming substrate wafer 110 is not completely etched, the discontinuous metal layer is formed on the peripheral portion of the through portion 53. 95 remains. Further, the bonding layer 98 which is the adhesion layer 91 where the discontinuous metal layer 95 is exposed also remains over the peripheral edge of the through portion 53.

  After the reservoir 100 is formed in this manner, although not shown, the drive IC 210 is mounted on the connection wiring 200 formed on the reservoir forming substrate wafer 130, and the drive IC 210 and the lead electrode 90 are connected by the drive wiring 220. Connecting. Thereafter, unnecessary portions of the outer peripheral edge portions of the flow path forming substrate wafer 110 and the reservoir forming substrate wafer 130 are removed by cutting, for example, by dicing. The nozzle plate 20 having the nozzle openings 21 is bonded to the surface of the flow path forming substrate wafer 110 opposite to the reservoir forming substrate wafer 130, and the compliance substrate 40 is attached to the reservoir forming substrate wafer 130. The ink jet recording head having the above-described structure is manufactured by bonding and dividing the flow path forming substrate wafer 110 and the like into a single chip size flow path forming substrate 10 as shown in FIG.

  As described above, in this embodiment, the through portion 53 is sealed with the discontinuous metal layer 95 including the adhesion layer 91 and the metal layer 92 that are the same layer as the lead electrode 90, and the discontinuous metal layer 95 is finally formed. Thus, the reservoir 31 and the communication part 13 are made to communicate with each other by removing them by etching. Thereby, unlike conventional mechanical processing, foreign matter such as processing residue does not occur. Accordingly, it is possible to reliably prevent the machining residue from remaining in the ink flow paths such as the pressure generation chamber 12 and the communication portion 13 and the occurrence of defective discharge such as nozzle clogging due to the remaining machining residue. Further, in the present invention, since the bonding layer 98 made of an oxidizing metal is provided in the bonding region between the flow path forming substrate 10 and the reservoir forming substrate 30, the adhesiveness of the adhesive 35 is improved, and the flow path forming substrate is improved. 10 and the reservoir forming substrate 30 are bonded well and firmly. Furthermore, in this embodiment, a part of the metal layer 92 constituting the discontinuous metal layer 95 is removed to expose the adhesion layer 91, and the exposed adhesion layer 91 functions as the bonding layer 98. The bonding strength between the flow path forming substrate 10 and the reservoir forming substrate 30 can be increased relatively easily without complicating the manufacturing process.

(Other embodiments)
As mentioned above, although embodiment of this invention was described, this invention is not limited to embodiment mentioned above. For example, in the embodiment described above, the adhesion layer 91 constituting the discontinuous metal layer 95 is also used as the bonding layer 98. However, the present invention is not limited to this, and the bonding layer 98 is, of course, the discontinuous metal layer 95. It may be provided separately. Further, when the bonding layer 98 is separately provided, the discontinuous metal layer 95 may not be present, and the manufacturing method in this case is not particularly limited.

  The ink jet recording head according to the above-described embodiment constitutes a part of a recording head unit including an ink flow path communicating with an ink cartridge or the like, and is mounted on the ink jet recording apparatus. FIG. 6 is a schematic view showing an example of the ink jet recording apparatus. As shown in FIG. 6, in the recording head units 1A and 1B having the ink jet recording head, cartridges 2A and 2B constituting the ink supply means are detachably provided. Is provided on a carriage shaft 5 attached to the apparatus body 4 so as to be movable in the axial direction. The recording head units 1A and 1B, for example, are configured to eject a black ink composition and a color ink composition, respectively. The driving force of the driving motor 6 is transmitted to the carriage 3 via a plurality of gears and timing belt 7 (not shown), so that the carriage 3 on which the recording head units 1A and 1B are mounted is moved along the carriage shaft 5. The On the other hand, the apparatus body 4 is provided with a platen 8 along the carriage shaft 5, and a recording sheet S, which is a recording medium such as paper fed by a paper feed roller (not shown), is conveyed on the platen 8. It is like that.

  Furthermore, in the above-described embodiments, the present invention has been described by exemplifying an ink jet recording head. However, the present invention is widely intended for all liquid ejecting heads and ejects liquids other than ink. Of course, it can also be applied. 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 (surface emitting 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. 3 is an exploded perspective view of the recording head according to the first embodiment. 2A and 2B are a plan view and a cross-sectional view of the recording head according to the first embodiment. 5 is a cross-sectional view illustrating a manufacturing process of the recording head according to Embodiment 1. FIG. 5 is a cross-sectional view illustrating a manufacturing process of the recording head according to Embodiment 1. FIG. 5 is a cross-sectional view illustrating a manufacturing process of the recording head according to Embodiment 1. FIG. 1 is a schematic view of a liquid ejecting apparatus according to an embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Flow path formation board | substrate, 12 Pressure generation chamber, 20 Nozzle plate, 21 Nozzle opening, 30 Reservoir formation board | substrate, 31 Reservoir part, 32 Piezoelectric element holding | maintenance part, 35 Adhesive agent, 40 Compliance board | substrate, 50 Elastic film, 55 Insulator film 53 Penetration part, 60 Lower electrode film, 70 Piezoelectric layer, 80 Upper electrode film, 90 Lead electrode, 91 Adhesion layer, 92 Metal layer, 95 Discontinuous metal layer, 98 Bonding layer, 100 Reservoir, 110 Channel formation substrate Wafer, 130 reservoir forming substrate wafer, 300 piezoelectric element

Claims (7)

A flow path forming substrate in which a pressure generating chamber communicating with a nozzle opening for discharging droplets is formed, and a lower electrode, a piezoelectric layer, and an upper electrode provided on one surface side of the flow path forming substrate via a vibration plate And a reservoir forming substrate provided with a reservoir portion that is bonded to the flow path forming substrate with an adhesive and forms a part of a reservoir that is a common liquid chamber of each pressure generating chamber, and It has a bonding layer made of an oxidizing metal in at least a part of a bonding region between the flow path forming substrate and the reservoir forming substrate, and the reservoir forming substrate is bonded onto the bonding layer. Liquid jet head. 2. The communication channel according to claim 1, wherein the flow path forming substrate includes a communication portion that forms a part of the reservoir in communication with the reservoir portion through a through portion provided in the diaphragm. A liquid ejecting head, wherein the liquid ejecting head is provided in at least a partial region around the portion. The liquid ejecting head according to claim 1, wherein the liquid ejecting head includes a lead electrode made of an adhesion layer and a metal layer and drawn from the piezoelectric element, and the joining layer is made of the adhesion layer. The liquid ejecting head according to claim 1, wherein the bonding layer is made of an alloy containing at least one selected from the group consisting of nickel, chromium, tin, aluminum, tantalum, titanium, and tungsten. . 5. The liquid ejecting head according to claim 1, wherein the adhesive is made of a material containing at least one of epoxy, silicone, and polyimide. A liquid ejecting apparatus comprising the liquid ejecting head according to claim 1. A lower electrode, a piezoelectric layer, and an upper electrode are arranged on one side of a flow path forming substrate in which a pressure generating chamber communicating with a nozzle opening for ejecting liquid and a communicating portion communicating with the pressure generating chamber are formed via a diaphragm. A piezoelectric element comprising: a step of removing the diaphragm in the region serving as the communicating portion to form a through portion; and an adhesion layer and a metal layer formed on the adhesion layer. A lead electrode to be drawn out is formed, and includes the adhesion layer and the metal layer, but the lead electrode seals the penetrating portion with a discontinuous metal layer that is discontinuous, and the metal layer that constitutes the discontinuous metal layer. Removing the part to expose a part of the adhesion layer; and exposing the reservoir forming substrate formed with a reservoir part communicating with the communicating part and constituting a part of the reservoir to the exposed part of the flow path forming substrate. The region including the adhesion layer Bonding the substrate with an adhesive, wet etching the flow path forming substrate from the other side until the diaphragm and the metal layer are exposed, and forming the pressure generating chamber and the communicating portion; A step of removing the discontinuous metal layer in a region corresponding to the portion by wet etching to cause the reservoir portion and the communication portion to communicate with each other.

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