JP2008238520A - Method for manufacturing liquid delivering head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a liquid delivering head capable of preventing foreign substances from being generated during etching. <P>SOLUTION: The method for manufacturing the liquid delivering head 100 in which wet etching processing is performed on a first work W1 to manufacture the liquid delivering head 100 under a condition that the first work W1 in which a mask 150 with a specified pattern is provided on a first face and a second work W2 are joined with each other comprises a covering step wherein the second work W2 and the outer peripheral side of the first face not opposing the second work W2 in the first work W1 are covered with a sealing sheet S1 with liquid resistance to the etching liquid used for the etching processing, and an etching processing step wherein after the covering step, the etching liquid is fed to the first face to perform the etching processing to the first work W1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method of manufacturing a liquid discharge head for forming a liquid discharge head.

  In an ink jet printer, a desired image is formed by ejecting ink from a recording head as a liquid ejection head onto an object to be printed. Some of such recording heads include a piezoelectric element such as a piezoelectric element, a pressure generation chamber for storing ink, a reservoir for supplying ink to the pressure generation chamber, and the like. In such a recording head, when the piezoelectric element expands and contracts while the pressure generating chamber is filled with ink, the expansion and contraction causes a volume change in the pressure generating chamber. The volume change enables ink droplets to be ejected from the nozzle openings.

  Such a recording head is currently formed using a printing technique. In order to further increase the density of the recording head, Patent Document 1 discloses a method of forming a recording head using a semiconductor manufacturing technique.

JP 2005-153242 A

  By the way, according to the method disclosed in Patent Document 1, in order to form the pressure generating chamber, the flow path forming substrate is wet-etched with an etching solution such as a KOH solution. Here, prior to the wet etching process, the flow path forming substrate is formed with an insulating film (mask film) serving as a mask on the nozzle opening side, and this insulating film matches the shape of the pressure generating chamber. Patterned. However, the flow path forming substrate is entirely formed with a silicon dioxide thin film (elastic film) prior to the process of forming the mask film, and the elastic film is formed on the outer peripheral wall surface of the flow path forming substrate. Remains.

  Here, at the corner edge part on the outer peripheral side of the flow path forming substrate, the boundary part between the mask film and the elastic film is not covered by either the mask film / elastic film, and an exposed part may occur. is there. Further, even if the above-mentioned boundary portion is not exposed and is covered with either the mask film or the elastic film, either the mask film or the elastic film may be very thin. When wet etching is performed in this state, the boundary portion is eroded by the etching solution.

  Then, a gap is formed between the elastic film and the outer peripheral wall surface of the flow path forming substrate, and the length of the gap gradually increases according to the etching processing time. Therefore, the elastic film is not supported by the outer peripheral wall surface of the flow path forming substrate. In some cases, a part of the elastic film is separated (peeled off) due to a part of the elastic film becoming very thin or an external impact applied. Here, the separated matter (foreign matter) separated from the elastic membrane can move in the etching solution. By such movement, foreign matter may enter a pressure generating chamber formed by performing an etching process.

  However, when foreign matter enters the pressure generation chamber, it becomes very difficult to remove the foreign matter from the pressure generation chamber due to adhesion of the foreign matter to the pressure generation chamber. If the recording head is formed with the foreign matter entering, the foreign matter may move to the nozzle opening when ink is supplied, and the nozzle opening may be clogged.

  As described above, when foreign matter is generated during the etching process, the recording head is clogged and the like, which causes a manufacturing failure of the recording head. Therefore, it is desired not to generate foreign matters during the etching process.

  The present invention has been made based on the above circumstances, and an object of the present invention is to provide a method of manufacturing a liquid discharge head capable of preventing foreign matters from being generated during an etching process. .

  In order to solve the above-described problems, the present invention provides a wet process for a first work in a state where a first work and a second work in which a mask having a predetermined pattern is provided on the first surface are joined. A manufacturing method of a liquid discharge head for manufacturing a liquid discharge head by performing an etching process, up to an outer peripheral side of a second surface and a first surface of the first work that does not face the second work A coating step of covering the substrate with a sealing sheet having resistance to the etching solution used in the etching process, and after the coating step, an etching solution is supplied to the first surface to perform the etching process on the first workpiece. An etching process step to be performed.

  When comprised in this way, the whole 2nd workpiece | work and the outer peripheral side of the 1st surface which does not oppose the 2nd workpiece among the 1st workpieces will be in the state covered with the sealing sheet. Here, at the corner edge portion on the outer peripheral side of the first workpiece, an exposed portion or a very thin state may occur at the boundary portion between the mask and the first workpiece. May be eroded by the etchant. However, as described above, it is possible to prevent the boundary portion from being eroded by the etchant by covering the outer peripheral side of the first surface of the first workpiece with the sealing sheet. For this reason, it is possible to prevent foreign matter from being generated by such erosion, and to prevent foreign matter from entering the pressure generating chamber of the liquid ejection head. Accordingly, it is possible to prevent foreign matter from moving to the nozzle opening during ink supply and causing the nozzle opening to be clogged.

  In addition, since the generation of foreign matter can be prevented as described above, it is possible to reduce the rate of occurrence of defects in the manufacture of the liquid ejection head and to improve the yield.

  According to another invention, in addition to the above-described invention, the first workpiece is a flow path forming substrate wafer in which at least a pressure generating chamber is formed. In addition, an oxide film formed by thermal oxidation is provided, and the second work is a protective substrate wafer used to form a protective substrate for protecting the piezoelectric element.

  When comprised in this way, while being able to protect the wafer for protective substrates with a sealing sheet, the outer peripheral wall surface of the wafer for flow path formation substrates can be protected with a sealing sheet. Therefore, since the boundary portion between the oxide film and the mask is covered with the sealing sheet, it is possible to prevent the elastic film from peeling off due to erosion by the etching solution.

  Furthermore, in another invention, in addition to the above-described invention, the sealing sheet is formed by applying an adhesive to the outer peripheral side of the region where the workpiece is formed in the flow path forming substrate wafer. The adhesive is fixed and attached, and this adhesive is an epoxy adhesive.

  When configured in this way, the sealing sheet is attached and fixed by the adhesive on the outer peripheral side of the region where the workpiece is formed, so that the manufacturing efficiency by the etching process of the flow path forming substrate wafer is deteriorated. This makes it possible to form the workpiece favorably. In addition, since the adhesive is an epoxy adhesive, it is possible to prevent the sealing by the adhesive from being broken even if an etching solution is attached, and it is possible to maintain a good sealing state (adhesion state). Become.

  In another invention, in addition to the above-described invention, the adhesive application region is provided on the outer peripheral side of the region where the workpiece is formed, and more than the region where the workpiece is formed. It is assumed that it is not provided in a region on the outer peripheral side where the plate thickness of the flow path forming substrate wafer is thin.

  When configured in this way, there is a possibility that chipping may occur due to the thin plate thickness when the adhesive is applied to the outer periphery of the flow path forming substrate wafer and the thin plate thickness. Such a chipping does not occur if the coating is not applied. Therefore, it is possible to reliably prevent the etchant from entering. In addition, it is possible to prevent deterioration of the work takeout property due to the curing of the adhesive.

  Further, according to another invention, in addition to each of the above-described inventions, the protective substrate wafer is provided with a piezoelectric element holding portion for protecting the piezoelectric element, and the piezoelectric element is flowed prior to the covering step. In addition to forming the piezoelectric element, the protective substrate wafer is attached and fixed to the flow path forming substrate wafer so as to cover the piezoelectric element after the piezoelectric element is formed.

  In such a configuration, the piezoelectric element is formed on the flow path forming substrate wafer, and the piezoelectric element is protected by the protective substrate wafer. For this reason, the piezoelectric element is not eroded by the etching solution, and the liquid discharge head can be formed while preventing adhesion of moisture or the like to the piezoelectric element.

  In another invention, in addition to the above-described inventions, the sealing sheet is made of polyparaphyllene telestal amide as a material.

  In the case of such a configuration, it is possible to prevent the wafers from being deformed such as warpage due to the heat generated during the etching process of the flow path forming substrate wafer. Moreover, a sealing sheet has chemical resistance with respect to etching liquid.

  Hereinafter, a recording head 100 provided in a printer 10 according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic diagram illustrating the configuration of the printer 10. 2 is an exploded perspective view showing an ink jet recording head 100 according to an embodiment of the present invention, FIG. 3 is a plan view of the recording head 100 in FIG. 1, and FIG. 2 is a cross-sectional view of the head 100. FIG.

<Schematic configuration of printer>
As shown in FIG. 1, the printer 10 includes, as main components, a housing unit (not shown), a carriage mechanism 20, a paper transport mechanism 30, a control unit 40, and a recording head 100 attached to the carriage. Yes.

  Among these, the carriage mechanism 20 includes a carriage 21, a carriage motor (CR motor 22), an endless belt 23, a gear pulley 24, a driven pulley 25, and a carriage shaft 26. Among these, the carriage 21 can mount the ink cartridges 27 of the respective colors. Further, the paper transport mechanism 30 includes a motor and a PF motor 31 as a transport motor for transporting a printing object P or the like as a transported object, and a paper feed roller 32 corresponding to the feeding of plain paper or the like. is doing.

  The control unit 40 includes an interface 41, a CPU (not shown), a memory, an ASIC (Application Specific Integrated Circuit), a bus, a timer, and the like. The control unit 40 receives signals from various sensors, and controls various motors such as the CR motor 22 and the PF motor 31 and the recording head 100 based on the signals from the sensors. .

  The printer 10 includes an interface 41. The printer 10 is connected to the computer 50 via the interface 41 (see FIG. 1). The computer 50 includes a CPU, RAM, ROM, HDD (Hard Disk Drive), interface, and the like (not shown). Among these, the HDD stores an application program for processing an image, a printer driver program, a video driver program, and the like.

<Details of recording head configuration>
Further, as shown in FIG. 1, a recording head 100 as a liquid ejection head capable of ejecting ink droplets is provided on the lower surface of the carriage 21. The recording head 100 is provided with a pressure generation chamber 111, a reservoir, and a piezoelectric element 170, which will be described later, associated with each ink. By the operation of the piezoelectric element 170, it is possible to eject ink droplets from the nozzle opening 131 at the end of the pressure generating chamber 111. In the present embodiment, the ink filled in the cartridge 27 may be any type of ink such as dye-based ink / pigment-based ink.

  As shown in FIG. 2, the recording head 100 includes a flow path forming substrate 110, an elastic film 120, a nozzle plate 130, and a protective substrate 140 as main components.

  Of these, the flow path forming substrate 110 is composed of a silicon single crystal substrate having a plane orientation (110) in the present embodiment. As shown in FIG. 4, a plurality of the flow path forming substrates 110 are integrated with a flow path forming substrate wafer W1 (corresponding to the first workpiece) for forming the flow path forming substrate 110 which is a silicon wafer. The flow path forming substrate wafer W1 is formed by forming liquid flow paths such as the pressure generating chamber 111, the ink supply path 112, and the communication portion 113, and then dividing the flow path forming substrate wafer W1. Is done.

  Among these, a large number of pressure generation chambers 111 are provided along the sub-scanning direction of the printer 10. A partition 114 is provided between adjacent pressure generation chambers 111. One pressure generation chamber 111 is provided for each nozzle opening 131 described later. In the present embodiment, the number of the pressure generating chambers 111 is provided, for example, 360 per inch (360 dpi) corresponding to the increase in the density of the nozzle openings 131. However, the number of the pressure generating chambers 111 is not limited to this, and can be variously changed, for example, 180 dpi.

  The ink supply path 112 is a part connecting the pressure generation chamber 111 and the communication portion 113, and is a flow path for supplying ink from the communication portion 113 to the pressure generation chamber 111. Therefore, the same number of ink supply paths 112 as the pressure generation chambers 111 are provided. As shown in FIG. 2, the ink supply path 112 is formed with a flow path diameter that is narrower than the width dimension of the pressure generating chamber 111. For this reason, the ink supply path 112 generates a certain flow path resistance when ink is introduced into the pressure generating chamber 111. The communication portion 113 that communicates with the ink supply path 112 is provided along the direction (longitudinal direction) in which the plurality of pressure generation chambers 111 are arranged. Therefore, the communication part 113 is provided in a long shape, for example, one for each nozzle row. Further, the communication portion 113 communicates with a reservoir portion 142 described later on the upper side thereof, and the reservoir portion 142 and the communication portion 113 constitute a reservoir 180.

  For example, when the pressure generation chambers 111 are arranged at about 180 (180 dpi) per inch, the thickness dimension of the flow path forming substrate 110 is about 180 to 280 μm, more preferably about 220 μm. Is preferred. For example, when the pressure generating chambers 111 are arranged at a relatively high density of about 360 dpi, the thickness of the flow path forming substrate 110 is preferably 100 μm or less. This is because the arrangement density can be increased while maintaining the rigidity of the partition 114 between the adjacent pressure generation chambers 111. In the present embodiment, since the arrangement density of the pressure generating chambers 111 is about 360 dpi, the thickness of the flow path forming substrate 110 is about 70 μm.

  Further, an elastic film 120 is formed on one surface (the upper side in FIG. 2) of the flow path forming substrate 110. The elastic film 120 is made of silicon dioxide, which is an oxide film formed by thermal oxidation at a stage prior to the formation of the pressure generation chamber 111 and the like. The thickness dimension of the elastic film 120 is, for example, 1 to 2 μm.

In addition, the nozzle plate 130 is disposed on the opening surface side (lower side in FIG. 2) of the flow path forming substrate 110 through a mask film (insulating film) 150 used as a mask when forming the pressure generating chamber 111 and the like. It is attached. Nozzle openings 131 are formed in the nozzle plate 130. When the nozzle plate 130 is attached to the flow path forming substrate 110, the nozzle opening 131 communicates with the pressure generation chamber 111 in the vicinity of the end of each pressure generation chamber 111 opposite to the ink supply path 112. The nozzle plate 130 is fixed to the flow path forming substrate 110 via an adhesive, a heat welding film, or the like. The nozzle plate 130 has a thickness dimension 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 non-rust steel.

Further, the insulating film 160 is attached to the flow path forming substrate 110 on the opposite side (upper side in FIG. 2) to the side where the nozzle plate 130 is attached, with the elastic film 120 interposed therebetween. The insulator film 160 is made of zirconium oxide (ZrO ₂ ) and has a thickness dimension of about 0.4 μm, for example. Furthermore, a piezoelectric element 170 is provided for each pressure generation chamber 111 on the insulator film 160. The piezoelectric element 170 includes a lower electrode film 171, a piezoelectric layer 172, and an upper electrode film 173. Among these, the lower electrode film 171 is formed by laminating platinum and iridium, and has a thickness dimension of about 0.2 μm. Of the piezoelectric elements 170, only the lower electrode film 171 has a large area so as to be common to all the piezoelectric elements 170 in the nozzle row. Further, the lower electrode film 171 is a common electrode.

  The piezoelectric layer 172 is made of, for example, lead zirconate titanate (PZT), and has a thickness dimension of, for example, about 1.0 μm. The piezoelectric layer 172 and the upper electrode film 173 are provided for each pressure generating chamber 111, and therefore, a predetermined gap is provided between the adjacent piezoelectric layer 172 and the upper electrode film 173. It becomes the state where the clearance gap of this space | interval is provided. The upper electrode film 173 is made of, for example, iridium (Ir), and has a thickness dimension of, for example, about 0.05 μm.

  In this embodiment, the lower electrode film 171 serves as a common electrode for the piezoelectric element 170 and the upper electrode film 173 serves as an individual electrode for the piezoelectric element 170, but this may be reversed.

  As shown in FIG. 4, in the piezoelectric element 170, the piezoelectric layer 172 and the upper electrode film 173 extend to one side (the right side in FIG. 4) of the lower electrode film 171. The upper electrode film 173 extending to one side is connected to a lead electrode 174 made of, for example, gold (Au), and the lead electrode 174 is connected to a drive circuit (not shown). Yes. A voltage is selectively applied to each piezoelectric element 170 through the lead electrode 174.

  In addition, the protective substrate 140 is bonded to the surface of the flow path forming substrate 110 on which the piezoelectric element 170 is provided (the upper surface in FIG. 2; corresponding to the first surface). The protective substrate 140 is provided with a piezoelectric element holding portion 141 formed through a process separate from the flow path forming substrate 110. The piezoelectric element holding portion 141 is a recessed portion that is recessed upward from below the protective substrate 140 in FIG. The piezoelectric element holding portion 141 is intended for protection from the external atmosphere of the piezoelectric element 170 (particularly moisture such as moisture), and is provided in a region facing the piezoelectric element 170. In addition, the piezoelectric element holding portion 141 is configured to have a spatial size that does not hinder the driving of the piezoelectric element 170.

  A reservoir portion 142 is provided in a region of the protective substrate 140 corresponding to the communication portion 113 of the flow path forming substrate 110. As described above, the reservoir portion 142 communicates with the communication portion 113 to form an integral space. Therefore, the reservoir portion 142 is provided in substantially the same shape as the communication portion 113 when the shape thereof is viewed in plan. The reservoir portion 142 is provided so as to penetrate the protective substrate 140 in the thickness direction in order to communicate with the communication portion 113. The reservoir unit 142 and the communication unit 113 serve as a common ink chamber for the pressure generation chamber 111. In the following description, this part (the reservoir unit 142 and the communication unit 113) is referred to as a reservoir 180.

  In addition, the protective substrate 140 is provided with a through hole 143. The through hole 143 is located between the piezoelectric element holding portion 141 and the reservoir portion 142 and is provided so as to penetrate the protective substrate 140. The through-hole 143 is a portion into which a conductive member enters to be electrically connected to the lead electrode 174 described above. Further, as shown in FIG. 4, a portion on one side (right side in FIG. 4) of the lead electrode 174 is approaching the through hole 143. Therefore, the lead electrode 174 and the conductive member are in a state of being electrically connected to each other well, for example, by performing wire bonding. Examples of the material of the protective substrate 140 include glass, a ceramic material, a metal, a resin, and the like. However, it is more preferable that the material of the protective substrate 140 is formed of substantially the same material as the thermal expansion coefficient of the flow path forming substrate 110. In this embodiment, a silicon single crystal of the same material as the flow path forming substrate 110 is used. It is formed using a substrate.

  In addition, as shown in FIGS. 2, 3, and 4, a compliance substrate 190 is bonded to a part of the upper side of the protective substrate 140. The compliance substrate 190 has a sealing film 191 and a fixing plate 192. Among these, the sealing film 191 is made of a material having low rigidity and flexibility, and examples thereof include a polyphenylene sulfide (PPS) film having a thickness dimension of 6 μm. With this sealing film 191, one side (the upper side in FIG. 2) of the reservoir portion 142 is sealed. The fixing plate 192 is provided on the upper side of the sealing film 191 in FIG. The fixing plate 192 is made of a hard material such as metal, and examples of the material include stainless steel (SUS) having a thickness dimension of 30 μm. The fixing plate 192 is provided with an opening 193. The opening 193 is provided in a region of the fixed plate 192 that faces the reservoir 180, and is configured by removing the fixed plate 192 in the thickness direction. Therefore, the portion of the compliance substrate 190 where the opening 193 exists seals the reservoir 180 only with the sealing film 191.

  Note that such a recording head 100 takes in ink from an external ink supply means (not shown) and fills the interior from the reservoir 180 to the nozzle opening 131 with ink. Thereafter, a voltage is applied between the lower electrode film 171 and the upper electrode film 173 corresponding to the pressure generation chamber 111 via an external wiring in accordance with a recording signal from a drive circuit (not shown). As a result, the elastic film 120, the lower electrode film 171 and the piezoelectric layer 172 are bent and deformed, and the volume in each pressure generating chamber 111 is changed by the bending deformation, and ink droplets are ejected from the nozzle openings 131.

<Method for manufacturing recording head>
Hereinafter, a method for manufacturing the above-described recording head 100 will be described with reference to FIGS. First, as shown in FIG. 6A, a silicon dioxide film, which is an oxide film constituting the elastic film 120, is formed on the surface of a flow path forming substrate wafer W1, which is a silicon wafer.

Next, as shown in FIG. 6B, an insulator film 160 made of zirconium oxide (ZrO ₂ ) is formed on the elastic film 120 (silicon dioxide film). Next, as shown in FIG. 6C, for example, after the lower electrode film 171 is formed by laminating platinum and iridium on the insulator film 160, the lower electrode film 171 is patterned into a predetermined shape.

  Subsequently, as shown in FIG. 6D, for example, a piezoelectric layer 172 made of lead zirconate titanate (PZT) or the like and an upper electrode film 173 made of iridium (Ir), for example, are formed on the flow path forming substrate. It is formed on the entire second surface of the wafer W1. Subsequently, as shown in FIG. 7A, the piezoelectric layer 172 and the upper electrode film 173 are patterned into a predetermined shape, and the piezoelectric elements 170 are formed in the regions to be the pressure generation chambers 111. Next, as shown in FIG. 7B, the lead electrode 174 is formed over the entire second surface of the flow path forming substrate 110, and the lead electrode 174 is formed for each piezoelectric element 170 in FIG. Pattern into the shape shown.

  Next, as shown in FIG. 7C, on the piezoelectric element 170 side, which is the second surface of the flow path forming substrate wafer W1, there is a protective substrate wafer W2 (first substrate) that is a silicon wafer and serves as the protective substrate 140. 2). Therefore, the rigidity of the flow path forming substrate wafer W1 is remarkably improved by bonding the protective substrate wafer W2.

  Next, as shown in FIG. 8A, the flow path forming substrate wafer W1 is polished by a polishing apparatus until it reaches a certain thickness.

  Subsequently, as shown in FIG. 8B, a mask film 150 is newly formed on the flow path forming substrate wafer W1 and patterned into a predetermined shape.

  Further, after patterning the mask film 150, the protective substrate wafer W2 is covered with a sealing sheet S1 made of polyparaphyllene telestalamide (PPTA), and the outer peripheral side W1b of the flow path forming substrate wafer W1 is sealed. The sealing sheet S1 is covered with the stop sheet S1, and the sealing sheet S1 is adhered to the outer peripheral side W1b with an adhesive. As a result of this adhesion, as shown in FIG. 10, the entire protective substrate wafer W2 is covered with the sealing sheet S1, and the outer peripheral side W1b of the flow path forming substrate wafer W1 is also covered with the sealing sheet S1. It becomes.

  The sealing sheet S1 is not adhered to the region where the plate thickness of the flow path forming substrate wafer W1 is thin even on the outer peripheral side of the flow path forming substrate wafer W1. This is because the outermost periphery of the flow path forming substrate wafer W1 has a thin plate thickness, and if an adhesive is applied to that region, the outermost periphery of the flow path forming substrate wafer W1 is chipped during bonding. This is because there is a fear. And the sealing sheet S1 is adhere | attached by apply | coating an adhesive agent in the shape of a ring on the outer side of the perforation of FIG. This application may be performed using a device such as a dispenser. In addition, as a dimension range for applying the adhesive, (1) it is necessary to prevent the KOH solution as an etching solution from entering, and it is necessary to apply it to a predetermined dimension or more. In addition, as this dimension range, (2) if the application range becomes too wide, the adhesive application portion is cured, so that the rigidity of the flow path forming substrate wafer W1 increases, and the flow path forming substrate When the wafer W1 is broken along the perforation in FIG. 5, there is a problem that the breakability is deteriorated. Therefore, 2 mm to 6 mm is preferable as a dimensional range for achieving both of these.

  In addition, the applied adhesive needs to have chemical resistance against a KOH solution that is an etching solution, and examples of such a material include an epoxy adhesive. Further, the sealing sheet S1 may be a planar (two-dimensional) sheet. However, in consideration of covering the protective substrate wafer W2 and the flow path forming substrate wafer W1 as shown in FIG. 10, a three-dimensionally molded product is used so as to form a bowl shape in advance. Also good.

  In the present embodiment, the sealing sheet S1 is bonded to the protective substrate wafer W2 with the protective sheet S2 interposed. In other words, the protective sheet S2 is bonded to a region facing the portion to be the protective substrate 140 of the protective substrate wafer W2. The sealing sheet S1 is bonded so as to cover the protective substrate wafer W2 and the like in a state where the protective sheet S2 is bonded. Thereby, for example, it is possible to prevent foreign matters such as dust and dirt adhering to the sealing sheet S1 from adhering to the surface of the protective substrate wafer W2. Further, the protective sheet S2 has an effect of preventing peeling or damage of a wiring pattern (not shown) provided in advance on the surface of the protective substrate wafer W2.

  As the material of the protective sheet S2, it is preferable to use a material that does not adversely affect the surface of the protective substrate wafer W2, that is, a polymer material that does not interfere with the surface of the protective substrate wafer W2. As such a material, for example, a fluororesin can be used, and in this embodiment, polytetrafluoroethylene (PTFE) or the like is used.

  In the present embodiment, the sealing sheet S1 is not bonded to the protective sheet S2, and as a result, there is a gap between the two as shown in FIG. If not, the protective sheet S2 and the sealing sheet S1 may be bonded. Moreover, you may employ | adopt the structure abbreviate | omitted, without providing protective sheet S2.

  Subsequently, the first surface of the flow path forming substrate wafer W1 is anisotropically etched through the mask film 150, so that the pressure is applied to the flow path forming substrate wafer W1 as shown in FIG. Liquid passages such as the generation chamber 111, the communication portion 113, and the ink supply passage 112 are formed. At this time, since the entire protective substrate wafer W2, the outer peripheral wall surface W1a of the flow path forming substrate wafer W1, and the outer peripheral side W1b of the flow path forming substrate wafer W1 are covered with the sealing sheet S1, these It is possible to reliably prevent the covered portion from being destroyed by the etching solution.

  Next, as shown in FIG. 9B, the sealing sheet S1 is cut and the sealing sheet S1 is removed. At the same time, the protective sheet S2 is also removed. Further, as shown in FIG. 9C, unnecessary portions of the outer peripheral edge portions of the flow path forming substrate wafer W1 and the protective substrate wafer W2, that is, the portion to which the sealing sheet S1 is bonded are, for example, dicing. It is removed by cutting with, for example. Then, the nozzle plate 130 having the nozzle openings 131 formed on the surface of the flow path forming substrate wafer W1 opposite to the protective substrate wafer W2 is bonded, and the compliance substrate 190 is bonded to the protective substrate wafer W2. Then, the flow path forming substrate wafer W1 or the like is divided into a single chip size flow path forming substrate 110 or the like as shown in FIG. Then, the nozzle plate 130 is bonded to the first surface of the flow path forming substrate 110. Thereby, the ink jet recording head 100 of the present embodiment is formed.

<Effect when the present invention is applied>
As described above, when the present invention is not applied, the boundary portion between the mask film 150 and the elastic film 120 is the mask film 150 / elastic film 120 at the outer peripheral edge of the flow path forming substrate wafer W1. An exposed part may occur without being covered by any of the above. Further, when the flow path forming substrate wafer W <b> 1 is polished as shown in FIG. 8A, a gap portion in which an etching solution such as a crack can enter may be formed in the elastic film 120. In addition, at this boundary portion, a very thin portion may occur in either the mask film 150 or the elastic film 120. When the wet etching process is performed in this state, the boundary portion is eroded by the etching solution. Thereby, a gap is gradually formed between the outer peripheral wall surface W1a of the flow path forming substrate wafer W1 and the elastic film 120 (see FIG. 10), and the elastic film 120 is separated by the growth of the gap. In some cases, foreign matter is formed.

  However, in the present embodiment, the entire protective substrate wafer W2 and the outer peripheral side W1b of the flow path forming substrate wafer W1 are covered with the sealing sheet S1. Therefore, the boundary portion between the mask film 150 and the elastic film 120 can be prevented from being eroded by the etching solution.

  Thereby, it is possible to prevent the generation of foreign matter, and it is possible to prevent the foreign matter from moving and entering the pressure generating chamber 111. Then, by preventing such foreign matter from entering (attaching) into the pressure generating chamber 111, the foreign matter moves to the nozzle opening 131 after the recording head 100 is formed, causing the nozzle opening 131 to be clogged. Can be prevented.

  In addition, it is possible to reduce the rate of occurrence of defects in the production of the recording head 100 and to improve the yield. In addition, since the yield can be improved, the manufacturing cost of the recording head 100 can be reduced. As for the conventional defect occurrence rate, for example, 38 recording heads 100 are formed from one flow path forming substrate wafer W1 or the like, and 3 to 4 of them are defective, but the present invention is applied. As a result, the occurrence of defects in the recording head 100 can be made almost zero from one flow path forming substrate wafer W1 or the like.

  Note that not only the flow path forming substrate wafer W1 but also the surface on the flow path forming substrate wafer W1 side of the protective substrate wafer W2, the etching solution is generated from the minute holes formed in the silicon dioxide film. In some cases, foreign matter may enter from that portion. However, in this embodiment, as shown in FIG. 10, since the entire protective substrate wafer W2 is covered with the sealing sheet S1, it is possible to prevent foreign matter from being generated from the protective substrate wafer W2 side. It is possible.

  Further, the sealing sheet S1 is attached and fixed by applying an adhesive on the outer periphery side of the region where the recording head 100 is formed in the flow path forming substrate wafer W1. Therefore, it is possible to satisfactorily perform the process for manufacturing the recording head 100 without deteriorating the manufacturing efficiency of the flow path forming substrate wafer W1 by the etching process. In addition, since the adhesive is an epoxy adhesive, it is possible to prevent the sealing by the adhesive from being broken even if an etching solution is attached, and it is possible to maintain a good sealing state (adhesion state). Become.

  Also, the adhesive application region is provided on the outer peripheral side with respect to the region where the workpiece is formed, and is on the outer peripheral side with respect to the region where the workpiece is formed, and the flow path forming substrate wafer W1. It is not provided in the region where the plate thickness is thin. This is because the outermost periphery of the flow path forming substrate wafer W1 has a thin plate thickness, and if an adhesive is applied to that region, the outermost periphery of the flow path forming substrate wafer W1 is chipped during bonding. This is because there is a fear. Therefore, by limiting the application region of the adhesive, it is possible to achieve both prevention of the etching solution intrusion and prevention of chipping of the flow path forming substrate wafer W1.

  Further, the piezoelectric element 170 is formed on the flow path forming substrate wafer W1, and the piezoelectric element 170 is protected by the protective substrate wafer W2. For this reason, the piezoelectric element 170 is not eroded by the etching solution, and the recording head 100 can be formed while preventing adhesion of moisture or the like to the piezoelectric element 170.

  Further, since the sealing sheet S1 is made of polyparaphyllene telestal amide as a material, the heat generated during the etching process of the flow path forming substrate wafer W1 may cause deformation such as warpage in each wafer. It is possible to prevent. In addition, since the sealing sheet S1 has chemical resistance (alkali resistance) against the etching solution, the entire protective substrate wafer W2, the outer peripheral wall surface W1a of the flow path forming substrate wafer W1, and the flow path forming substrate. Since the outer peripheral side W1b of the wafer W1 is covered with the sealing sheet S1, it is possible to reliably prevent these covered portions from being destroyed by the etching solution.

  Further, the sealing sheet S1 of the present invention is made of polyparaphyllene telestalamide (PPTA) and has a thermal expansion coefficient substantially equal to that of the flow path forming substrate wafer W1 and the protective substrate wafer W2 which are silicon wafers. is doing. Accordingly, it is possible to prevent the wafers W1 and W2 from being deformed by warping or the like due to heat generated during etching of the flow path forming substrate wafer W1.

<Modification of the present invention>
Although one embodiment of the present invention has been described above, the present invention can be variously modified in addition to this. This will be described below.

  In each of the above-described embodiments, the flow path forming substrate wafer W1 is used as the first workpiece, and the protective substrate wafer W2 is used as the second workpiece. However, the first workpiece and the second workpiece are not limited to these. For example, the first workpiece and the second workpiece may be glass substrates used for manufacturing a liquid crystal display.

  In this case, the liquid ejection head is used not for the printer 10 that prints on the printing object P such as paper, but for use in a liquid ejecting apparatus or the like used for manufacturing a liquid crystal display, an EL display, or the like. Become. In this case, the liquid may be a liquid other than ink. For example, in a device for ejecting a liquid used for a liquid crystal display or an EL display, the color material and the electrode material are liquid.

  Moreover, you may use the other material which has alkali resistance, for example, polyphenylene sulfide (PPS) etc. as a material of sealing sheet S1.

  In the above-described embodiment, for example, using an apparatus such as a dispenser, an adhesive is applied to the flow path forming substrate wafer W1, and the sealing sheet S1 is bonded and fixed. However, when the sealing sheet S1 is formed from a material that can be thermocompression bonded, the flow path forming substrate wafer W1 and the sealing sheet S1 may be thermocompression bonded. In addition, as a material of such sealing sheet S1, there exist a polypropylene film, a polyester film, etc. Further, as the sealing sheet S1, an ultraviolet curable film may be used. In this case, if ultraviolet rays are applied while applying a predetermined pressure, the flow path forming substrate wafer W1 and the sealing sheet S1 are bonded and fixed.

  Further, the printer 10 in each of the above-described embodiments may be a part of a complex device such as a configuration having functions (scanner function, copy function, etc.) other than the printer function.

1 is a diagram illustrating a schematic configuration of a printer according to an embodiment of the present invention. FIG. 2 is an exploded perspective view illustrating a configuration of a recording head in the printer of FIG. 1. FIG. 2 is a plan view of a recording head in the printer of FIG. 1. FIG. 4 is a cross section of the recording head taken along line AA in FIG. 3. It is a perspective view which shows the wafer for flow-path formation substrates. It is sectional drawing which shows the manufacturing process of a recording head. FIG. 7 is a cross-sectional view showing the recording head manufacturing process following FIG. 6. FIG. 8 is a cross-sectional view showing the recording head manufacturing process following FIG. 7. FIG. 9 is a cross-sectional view showing the manufacturing process of the recording head, following FIG. 8. It is sectional drawing which shows the sealing state by the sealing sheet of two wafers.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Printer, 20 ... Carriage mechanism, 21 ... Carriage, 100 ... Liquid discharge head (equivalent to a liquid discharge head), 110 ... Channel formation substrate, 111 ... Pressure generating chamber, 120 ... Elastic film, 130 ... Nozzle plate, 131 ... Nozzle opening, 140 ... Protective substrate, 141 ... Piezoelectric element holding part, 142 ... Reservoir part, 143 ... Through hole, 150 ... Mask film, 160 ... Insulator film, 170 ... Piezoelectric element, 171 ... Lower electrode film, 172 ... Piezoelectric layer, 173 ... upper electrode film, 174 ... lead electrode, 180 ... reservoir, 190 ... compliance substrate, W1 ... flow path forming substrate wafer (corresponding to the first workpiece), W2 ... protective substrate wafer (second) S1 ... sealing sheet, S2 ... protective sheet

Claims (6)

A liquid discharge head is manufactured by performing a wet etching process on the first work in a state where the first work and the second work on which a mask having a predetermined pattern is provided on the first surface are joined. A method of manufacturing a liquid discharge head for
Sealing that has liquid resistance to the etching solution used in the etching process up to the outer peripheral side of the first surface that does not oppose the second workpiece among the second workpiece and the first workpiece. A covering step covering with a sheet;
After the covering step, an etching process step of supplying the etching liquid to the first surface and performing an etching process on the first workpiece;
A method of manufacturing a liquid discharge head, comprising: The first workpiece is a flow path forming substrate wafer in which at least a pressure generating chamber is formed, and an outer peripheral wall surface of the flow path forming substrate wafer is provided with an oxide film by thermal oxidation,
The method of manufacturing a liquid discharge head according to claim 1, wherein the second workpiece is a protective substrate wafer used to form a protective substrate for protecting the piezoelectric element.   The sealing sheet is attached and fixed by applying an adhesive to the outer peripheral side of the region where the workpiece is formed in the flow path forming substrate wafer, and the adhesive is epoxy-based. The method of manufacturing a liquid discharge head according to claim 2, wherein the adhesive is an adhesive.   The adhesive application region is provided on the outer peripheral side of the region where the workpiece is formed, and is on the outer peripheral side of the region where the workpiece is formed, and the plate of the flow path forming substrate wafer 4. The method of manufacturing a liquid ejection head according to claim 3, wherein the liquid ejection head is not provided in a thin region. The protective substrate wafer is provided with a piezoelectric element holding portion for protecting the piezoelectric element,
Prior to the covering step, the piezoelectric element is formed on the flow path forming substrate wafer, and after forming the piezoelectric element, the protective substrate wafer is covered with the flow path forming substrate so as to cover the piezoelectric element. Mounting and fixing to the wafer,
The method of manufacturing a liquid discharge head according to claim 2, wherein the liquid discharge head is a liquid discharge head.   6. The method of manufacturing a liquid discharge head according to claim 1, wherein the sealing sheet is made of polyparaphyllene telestaramide as a material. 6.

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