JP2018039174A - Manufacturing method for pressure generation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce breakage of a piezoelectric layer in a manufacturing process while increasing a degree of freedom of wiring.SOLUTION: A manufacturing method for a pressure generation device includes the steps of: joining a first substrate formed with a pressure generation element having a first electrode, a second electrode and a piezoelectric layer interposed therebetween and a second substrate B formed with connection wiring 39 connecting the first electrode and the second electrode; forming a pressure chamber generating a pressure by the pressure generation element in the first substrate; and removing the connection wiring 39 and releasing connection between the first electrode and the second electrode subsequent to the step of forming the pressure chamber.SELECTED DRAWING: Figure 10A

Description

  The present invention relates to a technique for manufacturing a pressure generating device using a piezoelectric element or the like.

  Various pressure generating devices using a piezoelectric element having a piezoelectric layer interposed between a first electrode and a second electrode have been proposed. For example, a piezoelectric element used for ejecting a liquid in a liquid ejecting head is manufactured on a substrate through various manufacturing processes such as a cleaning process, a film forming process, and an etching process. Static electricity may be charged on the substrate and the piezoelectric layer may be damaged. In Patent Document 1, in the process of manufacturing a piezoelectric element, a connection wiring that conducts (shorts) the first electrode and the second electrode is formed, and the connection wiring is formed by cutting out the piezoelectric element from the substrate after manufacturing the piezoelectric element. A technique for preventing static electricity from being charged in the manufacturing process of the piezoelectric element by cutting is disclosed.

JP2013-146912A

  However, when the connection wiring is cut by cutting out the piezoelectric element from the substrate as in Patent Document 1, a space for wiring must be secured to the outside of the cut-out region, and the connection wiring must be formed in the space. The degree of freedom of wiring is reduced. In view of the above circumstances, an object of the present invention is to reduce damage to a piezoelectric layer in a manufacturing process while expanding the degree of freedom of wiring.

  In order to solve the above problems, a method for manufacturing a pressure generating device according to the present invention includes a first substrate on which a pressure generating element having a first electrode, a second electrode, and a piezoelectric layer interposed therebetween is formed, Bonding a second substrate on which a connection wiring connecting the first electrode and the second electrode is formed; forming a pressure chamber for generating pressure by the pressure generating element on the first substrate; and After the step of forming, a step of removing the connection wiring and releasing the connection between the first electrode and the second electrode is included. According to the above aspect, when the first substrate and the second substrate are joined, the first electrode and the second electrode are connected by the connection wiring, so that the first electrode and the second electrode are conducted and kept at the same potential. Can do. In this state, a pressure chamber is formed, and thereafter, the connection wiring is removed, and the connection between the first electrode and the second electrode is released. Since the process for forming the pressure chamber includes various manufacturing processes such as a cleaning process and an etching process for the substrate, static electricity is easily charged on the electrode of the pressure generating element and the substrate. According to this aspect, since the pressure chamber is formed in a state where the first electrode and the second electrode are electrically connected to each other by the connection wiring, the possibility that a high voltage caused by static electricity is applied to the piezoelectric layer is reduced. it can. In addition, in this aspect, the connection wiring that connects the first electrode and the second electrode is formed on the second substrate instead of the first substrate on which the pressure generating element is formed. There is no need to provide a dedicated space for connection wiring on the first substrate to be formed. For this reason, the freedom degree of wiring can be expanded significantly. Therefore, according to this aspect, damage to the piezoelectric layer in the manufacturing process can be reduced while expanding the degree of freedom of wiring.

  In a preferred aspect of the present invention, the connection wiring is formed in a region overlapping the region of the first substrate where the pressure generating element is formed in the second substrate. According to the above aspect, since the connection wiring can also be formed inside the cutout region of the second substrate, one pressure generating device can be used as compared with the case where a dedicated space for the connection wiring is required to the outside of the cutout region. Space in the substrate necessary for manufacturing can be reduced.

  In a preferred aspect of the present invention, connection wiring is formed on the surface of the second substrate opposite to the first substrate. According to the above aspect, the connection wiring is formed on the surface of the second substrate opposite to the first substrate, that is, the surface exposed when the first substrate and the second substrate are joined. Therefore, only the connection wiring can be removed by etching or the like.

  In a preferred aspect of the present invention, the connection wiring is formed inside the region where the driving IC for the pressure generating element is mounted on the second substrate. In the above aspect, since the connection wiring is formed inside the area where the driving IC for the pressure generating element is mounted on the second substrate, it is compared with the case where the connection wiring is formed outside the area where the driving IC is mounted. Thus, the space in the substrate necessary for manufacturing one pressure generating device can be further reduced.

  In a preferred aspect of the present invention, the connection wiring is formed outside the region of the second substrate cut out from the base material on which the second substrate is formed. In the above aspect, since the connection wiring is formed outside the region of the second substrate cut out from the base material on which the second substrate is formed, the connection wiring can also be removed by cutting out from the base material.

  In a preferred aspect of the present invention, the step of releasing the connection between the first electrode and the second electrode includes a step of removing the connection wiring by etching. According to the above aspect, since the connection wiring is removed by etching, the generation of burrs can be reduced as compared with the case where the connection wiring is removed by cutting out from the base material.

  In a preferred aspect of the present invention, the step of releasing the connection between the first electrode and the second electrode includes a step of removing the connection wiring by cutting out a region of the second substrate from the base material. According to the above aspect, the connection wiring can also be removed by cutting out the region of the second substrate from the base material. Therefore, it is not necessary to provide a separate process for removing the connection wiring separately from the cutting of the base material, and thus the manufacturing process can be simplified.

1 is a configuration diagram of a liquid ejecting apparatus according to a first embodiment of the present invention. FIG. 3 is an exploded perspective view of a liquid ejecting head. FIG. 3 is a sectional view of the liquid ejecting head shown in FIG. 2 taken along the line III-III. It is sectional drawing to which the structure of the pressure generation device was expanded. It is the top view which looked at the 1st substrate from the upper part. It is the top view which looked at the 2nd substrate from the upper part. It is a flowchart of the manufacturing method of a pressure generating device. It is sectional drawing of the process of the manufacturing method of a pressure generation device. It is sectional drawing of the process following FIG. 8A. It is sectional drawing of the process following FIG. 8B. It is sectional drawing of the process following FIG. 8C. FIG. 8D is a cross-sectional view of the step following FIG. 8D. FIG. 8E is a cross-sectional view of the step following FIG. 8E. It is a top view which shows a part of silicon substrate in which the 1st board | substrate was formed. It is a top view which shows a part of silicon substrate in which the 2nd board | substrate was formed. It is a top view of the process of the manufacturing method of a pressure generation device. FIG. 10B is a plan view of a step following FIG. 10A. It is a top view of a process of a manufacturing method of a pressure generating device in a 2nd embodiment. FIG. 11B is a plan view of a step following FIG. 11A. It is a top view of a process of a manufacturing method of a pressure generating device in a 3rd embodiment. It is a top view of the process following Drawing 12A.

<First Embodiment>
FIG. 1 is a configuration diagram illustrating a liquid ejecting apparatus 100 according to the first embodiment of the invention. The liquid ejecting apparatus 100 according to the first embodiment is an ink jet printing apparatus that ejects ink, which is an example of a liquid, onto the medium 12. The medium 12 is typically printing paper, but any print target such as a resin film or fabric can be used as the medium 12. As illustrated in FIG. 1, a liquid container 14 that stores ink is fixed to the liquid ejecting apparatus 100. For example, a cartridge that can be attached to and detached from the liquid ejecting apparatus 100, a bag-shaped ink pack formed of a flexible film, or an ink tank that can be refilled with ink is used as the liquid container 14. A plurality of types of inks having different colors are stored in the liquid container 14.

  As illustrated in FIG. 1, the liquid ejecting apparatus 100 includes a control device 20, a transport mechanism 22, a moving mechanism 24, and a plurality of liquid ejecting heads 26. The control device 20 includes, for example, a processing circuit such as a CPU (Central Processing Unit) or FPGA (Field Programmable Gate Array) and a storage circuit such as a semiconductor memory, and comprehensively controls each element of the liquid ejecting apparatus 100. The transport mechanism 22 transports the medium 12 in the Y direction under the control of the control device 20.

  The moving mechanism 24 reciprocates the plurality of liquid jet heads 26 in the X direction under the control of the control device 20. The X direction is a direction that intersects (typically orthogonal) the Y direction in which the medium 12 is conveyed. The moving mechanism 24 includes a substantially box-shaped transport body (carriage) 242 that houses a plurality of liquid jet heads 26, and an endless belt 244 to which the transport body 242 is fixed. Note that the liquid container 14 can be mounted on the transport body 242 together with the liquid ejecting head 26.

  Each of the plurality of liquid ejecting heads 26 ejects ink supplied from the liquid container 14 to the medium 12 from a plurality of nozzles (ejection holes) under the control of the control device 20. In parallel with the transport of the medium 12 by the transport mechanism 22 and the reciprocating reciprocation of the transport body 242, each liquid ejecting head 26 ejects ink onto the medium 12, whereby a desired image is formed on the surface of the medium 12. A direction perpendicular to the XY plane (for example, a plane parallel to the surface of the medium 12) is hereinafter referred to as a Z direction. The ink ejection direction (typically the vertical direction) by each liquid ejection head 26 corresponds to the Z direction.

  FIG. 2 is an exploded perspective view of any one liquid ejecting head 26, and FIG. 3 is a cross-sectional view taken along line III-III in FIG. As shown in FIG. 2, the liquid ejecting head 26 includes a plurality of nozzles N arranged in the Y direction. The plurality of nozzles N of the first embodiment are divided into a first row L1 and a second row L2. Although it is possible to make the position of the nozzle N in the Y direction different between the first row L1 and the second row L2 (that is, staggered arrangement or staggered arrangement), the nozzles in the first row L1 and the second row L2 A configuration in which the positions of N in the Y direction are matched is illustrated in FIG. 3 for convenience. As shown in FIG. 2, the liquid ejecting head 26 has a structure in which elements related to the plurality of nozzles N in the first row L1 and elements related to the plurality of nozzles N in the second row L2 are arranged substantially line-symmetrically. is there.

  As shown in FIGS. 2 and 3, the liquid ejecting head 26 includes a flow path substrate 32. The flow path substrate 32 is a plate-like member including a first surface F1 and a second surface F2. The first surface F1 is a surface on the positive side in the Z direction (surface on the medium 12 side), and the second surface F2 is a surface on the opposite side (the negative side in the Z direction) from the first surface F1. The pressure generating device 35 and the casing 40 are installed on the second surface F2 of the flow path substrate 32, and the nozzle plate 52 and the vibration absorber 54 are installed on the first surface F1. The pressure generating device 35 is an element that generates pressure for ejecting ink from the nozzles N. Each element of the liquid jet head 26 is generally a plate-like member that is long in the Y direction, similarly to the flow path substrate 32, and is bonded to each other using, for example, an adhesive. For example, the pressure generating device 35 is configured by bonding a first substrate A including a pressure chamber substrate 34, a vibrating portion 36, and a plurality of piezoelectric elements 37, a second substrate B including a wiring connection substrate 38, and a driving IC 62. The Details of the pressure generating device 35 will be described later.

  The nozzle plate 52 is a plate-like member on which a plurality of nozzles N are formed, and is installed on the first surface F1 of the flow path substrate 32 using, for example, an adhesive. Each nozzle N is a through hole through which ink passes. The nozzle plate 52 of the first embodiment is manufactured by processing a silicon (Si) single crystal substrate using a semiconductor manufacturing technique (for example, etching). However, known materials and manufacturing methods can be arbitrarily employed for manufacturing the nozzle plate 52.

  The flow path substrate 32 is a plate-like member for forming an ink flow path. As shown in FIGS. 2 and 3, the flow path substrate 32 is formed with a space RA, a plurality of supply flow paths 322, and a plurality of communication flow paths 324 for each of the first row L1 and the second row L2. The The space RA is a long opening along the Y direction in plan view (that is, viewed from the Z direction), and the supply flow path 322 and the communication flow path 324 are through holes formed for each nozzle N. The plurality of supply channels 322 are arranged in the Y direction, and the plurality of communication channels 324 are arranged in the Y direction as well. Further, as shown in FIG. 3, an intermediate flow path 326 that extends over a plurality of supply flow paths 322 is formed on the first surface F 1 of the flow path substrate 32. The intermediate flow path 326 is a flow path that connects the space RA and the plurality of supply flow paths 322. On the other hand, the communication flow path 324 communicates with the nozzle N.

  2 and 3 is a case for storing ink to be supplied to a plurality of pressure chambers C (and a plurality of nozzles N). The surface on the positive side in the Z direction of the housing part 40 is fixed to the second surface F2 of the flow path substrate 32 with an adhesive, for example. As shown in FIGS. 2 and 3, a groove-like recess 42 extending in the Y direction is formed on the positive surface of the housing 40 in the Z direction. The wiring connection board 38 and the drive IC 62 are accommodated inside the recess 42. The casing 40 is formed of a material different from the flow path substrate 32 and the pressure chamber substrate 34. For example, the housing part 40 can be manufactured by injection molding of a resin material. However, a known material and manufacturing method may be arbitrarily adopted for manufacturing the housing unit 40. As a material of the housing portion 40, for example, a synthetic fiber such as polyparaphenylene benzobisoxazole (Zylon [registered trademark]) or a resin material such as a liquid crystal polymer is preferable.

  As shown in FIG. 3, a space RB is formed in the housing portion 40 for each of the first row L1 and the second row L2. The space RB of the housing unit 40 and the space RA of the flow path substrate 32 communicate with each other. The space constituted by the space RA and the space RB functions as a liquid storage chamber (reservoir) R that stores ink supplied to the plurality of pressure chambers C. The liquid storage chamber R is a common liquid chamber extending over a plurality of nozzles N. On the surface of the housing 40 opposite to the flow path substrate 32, the inlets 43 for introducing the ink supplied from the liquid container 14 into the liquid storage chamber R are the first row L1 and the second row L2. Formed for each of.

  The ink supplied from the liquid container 14 to the introduction port 43 is stored in the space RB and the space RA of the liquid storage chamber R. The ink stored in the liquid storage chamber R branches from the intermediate flow path 326 into a plurality of supply flow paths 322 and is supplied and filled in the pressure chambers C in parallel.

  As shown in FIG. 2, a vibration absorber 54 is installed on the first surface F1. The vibration absorber 54 is a flexible film (compliance substrate) that absorbs pressure fluctuations of ink in the liquid storage chamber R. As shown in FIG. 3, the vibration absorber 54 is installed on the first surface F1 of the flow path substrate 32 so as to close the space RA of the flow path substrate 32, the intermediate flow path 326, and the plurality of supply flow paths 322. A wall surface (specifically, a bottom surface) of the liquid storage chamber R is configured.

(Configuration of pressure generating device)
FIG. 4 is an enlarged cross-sectional view of the pressure generating device 35. FIG. 5 is a plan view of the first substrate A constituting the pressure generating device 35 as viewed from the Z direction (above). FIG. 6 is a plan view of the second substrate B constituting the pressure generating device 35 as viewed from the Z direction (above). As shown in FIGS. 2 to 6, the pressure generating device 35 is configured by stacking a first substrate A, a second substrate B, and a driving IC 62. The first substrate A is a substrate including the pressure chamber substrate 34, the vibration unit 36, and the plurality of piezoelectric elements 37, and the second substrate B is a substrate including the wiring connection substrate 38.

  As shown in FIGS. 2 to 4, the pressure chamber substrate 34 is a plate-like member in which a plurality of openings 342 arranged in the Y direction are formed in each of the first row L1 and the second row L2. It is installed on the second surface F2 of the flow path substrate 32 using an agent. The opening 342 is a long through hole formed for each nozzle N and extending in the X direction in plan view. The flow path substrate 32 and the pressure chamber substrate 34 are manufactured by processing a base material, for example, a silicon (Si) single crystal substrate (silicon substrate) using a semiconductor manufacturing technique, like the nozzle plate 52 described above. The However, known materials and manufacturing methods can be arbitrarily employed for manufacturing the flow path substrate 32 and the pressure chamber substrate 34.

  A vibrating portion 36 is installed on the surface of the pressure chamber substrate 34 opposite to the flow path substrate 32. The vibration part 36 is a plate-like member (vibration plate) that can elastically vibrate. In addition, the pressure chamber substrate 34 and the vibration part 36 may be integrally formed by selectively removing a part in the plate thickness direction in a region corresponding to the opening 342 of the plate-like member having a predetermined plate thickness. Is possible.

  As shown in FIG. 3, the second surface F <b> 2 of the flow path substrate 32 and the vibrating portion 36 face each other with an interval inside each opening 342. A space located between the second surface F2 of the flow path substrate 32 and the vibration part 36 inside the opening 342 functions as a pressure chamber C for applying pressure to the ink filled in the space. The pressure chamber C is individually formed for each nozzle N. As shown in FIG. 2, a plurality of pressure chambers C (openings 342) are arranged in the Y direction for each of the first row L1 and the second row L2. One arbitrary pressure chamber C communicates with the space RA via the supply flow path 322 and the intermediate flow path 326 and also communicates with the nozzle N via the communication flow path 324. It is also possible to add a predetermined channel resistance by forming a narrow channel with a narrow channel width in the opening 342.

  As shown in FIGS. 2 to 5, a plurality of piezoelectric elements 37 corresponding to different nozzles N are arranged in the first row L1 and the second row L2 on the surface of the vibrating portion 36 opposite to the pressure chamber C. Installed for each. The piezoelectric element 37 is a pressure generating element that generates a pressure in the pressure chamber C by being deformed by supplying a drive signal. The plurality of piezoelectric elements 37 are arranged in the Y direction so as to correspond to each pressure chamber C.

  As shown in FIG. 4, the piezoelectric element 37 is a stacked body in which a piezoelectric layer 373 is interposed between a first electrode 371 and a second electrode 372 facing each other. As shown in FIGS. 4 and 5, the first electrode 371 of the first embodiment is a plurality of lower electrodes arranged in the X direction, and the second electrode 372 is arranged so as to overlap a part of each first electrode 371. The rectangular upper electrode. However, the first electrode 371 may be an upper electrode and the second electrode 372 may be a lower electrode. A portion of the piezoelectric layer 373 where the first electrode 371 and the second electrode 372 overlap (the hatched portion in FIG. 5) is driven. When the vibration part 36 vibrates in conjunction with the deformation of the piezoelectric element 37, the pressure in the pressure chamber C fluctuates, so that the ink filled in the pressure chamber C is ejected through the communication channel 324 and the nozzle N. Is done.

  2 and 3 is a plate-like member for protecting the plurality of piezoelectric elements 37, and is installed on the surface of the vibration unit 36 (or the surface of the pressure chamber substrate 34). The material and manufacturing method of the wiring connection substrate 38 are arbitrary, but the wiring connection substrate 38 can be obtained by processing, for example, a silicon (Si) single crystal substrate by a semiconductor manufacturing technique, like the flow path substrate 32 and the pressure chamber substrate 34. Can be formed.

  As shown in FIG. 4, a drive IC 62 is installed on the surface (hereinafter referred to as “mounting surface”) G2 of the wiring connection board 38 opposite to the surface (hereinafter referred to as “joint surface”) G1 on the vibration part 36 side. The The drive IC 62 is a substantially rectangular IC chip on which a drive circuit that drives each piezoelectric element 37 by generating and supplying a drive signal under the control of the control device 20 is mounted. As shown in FIGS. 3 and 4, at least a part of the piezoelectric elements 37 of the liquid ejecting head 26 overlap the drive IC 62 in plan view. As described above, in the first embodiment, since the drive IC 62 is installed near the piezoelectric element 37, the drive IC 62 is driven from the drive IC 62 by a piezoelectric circuit as compared with a configuration in which the drive IC 62 is mounted on a wiring board fixed to the wiring connection board 38. The path length to the element 37 is shortened, and the signal distortion due to the resistance component and the capacitance component of the path can be reduced.

  As shown in FIG. 6, the first wiring 384 connected to the output terminal of the drive signal (drive voltage) COM of the drive IC 62 is formed for each piezoelectric element 37 on the mounting surface G <b> 2 of the wiring connection board 38. A second wiring 385 connected to the output terminal of the base voltage VBS of the driving IC 62 is continuously formed in the Y direction along the arrangement of the piezoelectric elements 37 on the mounting surface G2 of the wiring connection board 38. One end 385a and the other end 385b of the second wiring 385 are formed so as to penetrate the wiring connection substrate 38 from the positive surface to the negative surface in the Z direction. One end 385a and the other end 385b of the second wiring 385 are connected to an intermediate portion 385c formed on the surface of the wiring connection substrate 38 on the positive side in the Z direction so as to extend in the X direction.

  A first terminal P1 and a second terminal P2 are formed on the surface of the pressure chamber substrate 34 (vibrating portion 36). The first terminal P 1 is electrically connected to the first electrode 371 of the piezoelectric element 37, and the second terminal P 2 is electrically connected to the second electrode 372 of the piezoelectric element 37. For example, a known resin core bump in which a protrusion formed of a resin material is covered with a conductive material is suitable as the first terminal P1 and the second terminal P2. In a state where the pressure chamber substrate 34 (first substrate A) and the wiring connection substrate 38 (second substrate B) are bonded to each other, each first wiring 384 has a conduction hole (contact hole) penetrating the wiring connection substrate 38. ) It is electrically connected to the first terminal P1 through H1. The second wiring 385 is connected to the second terminal P2 via a conduction hole (contact hole) H2 penetrating the wiring connection board 38 and a conduction groove H3 formed on the surface of the wiring connection board 38 on the positive side in the Z direction. Electrically connected. The drive signal COM output from the output terminal of the drive IC 62 is applied to the first electrode 371 of each piezoelectric element 37 via the terminal 384a of each first wiring 384, the conduction hole H1, and the first terminal P1. The base voltage VBS output from the output terminal of the drive IC 62 is applied to the second electrode 372 of the piezoelectric element 37 via the second wiring 385, the conduction hole H2, the conduction groove H3, and the second terminal P2.

  Further, as shown in FIG. 2, a plurality of wirings 388 including wirings for the driving signal COM and the base voltage VBS connected to the input terminals of the driving IC 62 are formed on the mounting surface G2 of the wiring connection board 38. The plurality of wirings 388 extend to a region E located at the end in the Y direction (that is, the direction in which the plurality of piezoelectric elements 37 are arranged) on the mounting surface G2 of the wiring connection board 38. The wiring member 64 is joined to the region E of the mounting surface G2. The wiring member 64 is a mounting component on which a plurality of wirings (not shown) that electrically connect the control device 20 and the drive IC 62 are formed. For example, a flexible wiring board such as FPC (Flexible Printed Circuit) or FFC (Flexible Flat Cable) is suitably used as the wiring member 64. As described above, the wiring connection board 38 also functions as a wiring board on which wirings (384, 388) for transmitting drive signals are formed. However, it is also possible to install a wiring board used for mounting the drive IC 62 and forming a wiring separately from the wiring connection board 38.

<Method for manufacturing pressure generating device>
Next, a method for manufacturing the pressure generating device 35 in the first embodiment will be described. FIG. 7 is a flowchart of the manufacturing method of the pressure generating device 35 in the first embodiment. The process of the method for manufacturing the pressure generating device 35 of the first embodiment is a part of the process of the method for manufacturing the liquid jet head 26. The manufacturing method of the pressure generating device 35 includes a first substrate A on which a piezoelectric element 37 having at least a first electrode 371, a second electrode 372, and a piezoelectric layer 373 interposed therebetween, a first electrode 371, The step of joining the second substrate B on which the connection wiring 39 for connecting the two electrodes 372 is formed (step S301), and the step of forming the pressure chamber C for generating pressure by the piezoelectric element 37 on the first substrate A (step S301). Step S302) and the step of forming the pressure chamber C include a step of removing the connection wiring 39 and releasing the connection between the first electrode 371 and the second electrode 372 (Step S303).

  As shown in FIG. 7, in the method for manufacturing the pressure generating device 35 of the first embodiment, the first substrate A is manufactured with a silicon substrate (silicon wafer) WA in step S101, and in steps S201 and 202, the first substrate A is manufactured. The second substrate B is manufactured using a separate silicon substrate WB. After step S301, the first substrate A and the second substrate B are bonded by bonding the silicon substrates WA and WB to form the pressure generating device 35, and the region of the pressure generating device 35 is cut out from the silicon substrate. By mounting the driving IC 62 on the second substrate B, the pressure generating device 35 is manufactured. In this way, by manufacturing a plurality of first substrates A and a plurality of second substrates B on each of the silicon substrates, a plurality of pressure generating devices 35 can be manufactured at a time.

  Hereinafter, each step will be specifically described. 8A to 8F are cross-sectional views for explaining the steps of the method for manufacturing the pressure generating device. FIG. 9A is a plan view showing a part of the silicon substrate WA on which the first substrate A is formed, and FIG. 9B is a plan view showing a part of the silicon substrate WB on which the second substrate B is formed. 10A and 10B are plan views of the steps of the method for manufacturing the pressure generating device. FIG. 10A shows the second substrate B before the connection wiring 39 is removed, and FIG. 10B shows the second substrate B after the connection wiring 39 is removed.

  Step S101 is a process of forming the first substrate A. In step S101, as shown in FIG. 9A, the vibration part 36, the piezoelectric element 37, the first terminal P1, and the second terminal P2 are formed in the region where the first substrate A of the silicon substrate WA is formed. For example, the piezoelectric element 37 is formed by forming the first electrode 371, the piezoelectric layer 373, and the second electrode 372 in this order on the silicon substrate WA by film formation such as sputtering.

  Step S201 is a step of forming the second substrate B, and step S202 is a step of forming connection wiring. In step S201, conductive holes (contact holes) H1, H2, and H3 are formed in the silicon substrate WB by etching. The first wiring 384 and the second wiring 385 are formed, and the connection wiring 39 that connects the first wiring 384 and the second wiring 385 to each other is formed. The connection wiring 39 is a wiring for conducting the first electrode 371 and the second electrode 372. As shown in FIG. 9B, the connection wiring 39 of the first embodiment is formed in a region overlapping the region of the first substrate A on which the piezoelectric element 37 is formed.

  Step S301 is a process of bonding the first substrate A and the second substrate B. The first substrate A and the second substrate B are joined by joining the silicon substrates WA and WB together. As shown in FIG. 8A, the silicon substrates WA and WB are bonded together so that the second substrate B overlaps the first substrate A. By joining the first substrate A and the second substrate B, the first electrode 371 and the second electrode 372 are electrically connected by the connection wiring 39.

  Specifically, as shown in FIG. 8B, since the first wiring 384 contacts the first terminal P1, the first wiring 384 is connected to the first electrode 371 by the first terminal P1. Since the second wiring 385 contacts the second terminal P2, the second wiring 385 is connected to the second electrode 372 by the second terminal P2. As a result, the first electrode 371 and the second electrode 372 are electrically connected to each other and can be held at the same potential by the connection wiring 39 that is electrically connected to the first wiring 384 and the second wiring 385.

  Next, in step S302, the pressure chamber C is formed in a state where the first electrode 371 and the second electrode 372 are electrically connected, and then the connection wiring 39 is removed in step S303. Specifically, in step S302, as shown in FIG. 8C, an opening 342 constituting the pressure chamber C is formed in the first substrate A by etching. In step S303, as shown in FIG. 8D, the connection wiring 39 is removed by etching. For example, by etching the region Q3 surrounded by the dotted line in FIG. 10A, the connection wiring 39 is removed as shown in FIG. 10B, so that the connection between the first electrode 371 and the second electrode 372 is released.

  Subsequently, in step S304, the silicon substrates WA and WB are cut. Specifically, as shown in FIG. 8E, the region Q1 of the pressure generating device 35 is cut out by cutting the silicon substrates WA and WB along the cutting line CL. In step S305, the driving IC 62 is mounted on the second substrate B. Specifically, as shown in FIG. 8F, the second substrate B is bonded to the region Q2 where the driving IC 62 is mounted. When the driving IC 62 is mounted, the first electrode 371 of the piezoelectric element 37 is connected to the output terminal of the driving signal COM of the driving IC 62 via the terminal 384a of the first wiring 384, the conduction hole H1, and the first terminal P1. . The second electrode 372 of the piezoelectric element 37 is connected to the output terminal of the base voltage VBS of the drive IC 62 through the second wiring 385, the conduction hole H2, the conduction groove H3, and the second terminal P2. Thus, the pressure generating device 35 shown in FIG. 4 is manufactured.

  As described above, in the method for manufacturing the pressure generating device 35 of the first embodiment, when the first substrate A and the second substrate B are joined in step S301, the first electrode 371 and the second electrode 372 are connected by the connection wiring 39. Are connected to each other, the first electrode 371 and the second electrode 372 are brought into conduction and can be kept at the same potential. In this state, the pressure chamber C is formed in step S302, and then the connection wiring 39 is removed in step S303, and the connection between the first electrode 371 and the second electrode 372 is released. Since the process of forming the pressure chamber C includes various manufacturing processes such as a cleaning process and an etching process for the silicon substrates WA and WB, for example, if the first electrode 371 and the second electrode 372 of the piezoelectric element 37 are not at the same potential, The first electrode 371 and the second electrode 372 are easily charged with static electricity. For example, when cleaning water is used in the cleaning process, the charged cleaning water adheres to the first electrode 371 and the second electrode 372, and thus static electricity may be charged.

  In this regard, according to the present embodiment, the pressure chamber C is formed in a state where the first electrode 371 and the second electrode 372 are electrically connected to each other by the connection wiring 39, and thus the first electrode 371 and the first electrode 371 of the piezoelectric element 37 are formed. It is difficult for static electricity to be charged to the two electrodes 372, and the possibility that a high voltage resulting from static electricity is applied to the piezoelectric layer can be reduced. In addition, in the present embodiment, the connection wiring 39 that connects the first electrode 371 and the second electrode 372 is formed not on the first substrate A on which the piezoelectric element 37 is formed but on the second substrate B. Therefore, it is not necessary to provide a dedicated space for connection wiring on the first substrate A on which the piezoelectric element 37 is formed. For this reason, the freedom degree of wiring can be expanded significantly. Therefore, according to the manufacturing method of the present embodiment, damage to the piezoelectric layer 373 in the manufacturing process can be reduced while expanding the degree of freedom of wiring.

  According to the manufacturing method of the present embodiment, a region overlapping the region of the first substrate A on which the piezoelectric element 37 is formed on the second substrate B, that is, the inside of the cutout region of the second substrate B (see FIG. The connection wiring 39 can also be formed in a region inside the cutting line CL shown in 10A. This makes it possible to reduce the space in the silicon substrates WA and WB necessary for manufacturing one pressure generating device 35 as compared with the case where a dedicated space for connection wiring is required to the outside of the cutout region.

  The connection wiring 39 is formed on the surface of the second substrate B opposite to the bonding surface with the first substrate A, that is, the surface exposed when the first substrate A and the second substrate B are bonded. According to this, only the connection wiring 39 can be removed by etching or the like. By removing the connection wiring 39 by etching, the generation of burrs can be reduced as compared with the case of removing the connection wiring 39 by cutting out from the silicon substrates WA and WB.

Second Embodiment
A second embodiment of the present invention will be described. FIG. 11A and FIG. 11B are plan views of the steps of the method for manufacturing the pressure generating device in the second embodiment. FIG. 11A shows the second substrate B before the connection wiring 39 is removed, and FIG. 11B shows the second substrate B after the connection wiring 39 is removed. In addition, about the element which an effect | action and function are the same as 1st Embodiment in 2nd Embodiment, the code | symbol used by description of 1st Embodiment is diverted, and each detailed description is abbreviate | omitted suitably.

In the first embodiment, the case where the connection wiring 39 is formed outside the region where the driving IC 62 of the piezoelectric element 37 is mounted on the second substrate B is exemplified. However, in the second embodiment, the piezoelectric element is formed on the second substrate B. The case where the connection wiring 39 is formed inside the region where the 37 driving ICs 62 are mounted will be exemplified. Specifically, as shown in FIG. 11A, the intermediate portion 385c of the second wiring 385 is formed on the negative surface in the Z direction of the wiring connection substrate 38 (the negative surface in the Z direction of the second substrate B). Each of the first wirings 384 is connected to the intermediate portion 385c. A portion obtained by extending the first wiring 384 to the intermediate portion 385 c of the second wiring 385 is referred to as a connection wiring 39.
In the second embodiment, the region Q3 surrounded by the dotted line shown in FIG. 11A is removed by etching in step S303 of FIG. 7, so that the connection wiring 39 (the intermediate portion 385c of the second wiring 385 is shown in FIG. 11B). The portion extending up to) is removed. Also according to the second embodiment, since the connection wiring 39 is removed after the step of forming the pressure chamber C, the same effect as that of the first embodiment can be obtained. Moreover, in the second embodiment, since the connection wiring 39 is formed inside the region where the drive IC 62 of the piezoelectric element 37 is mounted on the second substrate B, the connection wiring 39 is formed outside the region where the drive IC 62 is mounted. Compared with the case where it is formed, the space in the silicon substrates WA and WB required for manufacturing one pressure generating device 35 can be further reduced.

<Third Embodiment>
A third embodiment of the present invention will be described. 12A and 12B are plan views of the steps of the method for manufacturing the pressure generating device according to the third embodiment. 12A shows the second substrate B before the connection wiring 39 is removed, and FIG. 12B shows the second substrate B after the connection wiring 39 is removed.

In the first embodiment, the case where the connection wiring 39 is formed inside the cut-out region of the second substrate B cut out from the silicon substrate WB on which the second substrate B is formed is illustrated, but in the third embodiment, the second The case where the connection wiring 39 is formed outside the cutout region of the substrate B is illustrated. Specifically, as shown in FIG. 12A, the connection wiring 39 is formed in a region outside the cutting line CL in the silicon substrate WB. FIG. 12A shows an example in which two second substrates B are formed on one silicon substrate WB. In this case, as shown in FIG. 12A, a plurality of second substrates B may be connected by a common connection wiring 39. Note that the present invention is also applicable when three or more second substrates B are formed on one silicon substrate WB.
In the third embodiment, the connection wiring 39 is removed as shown in FIG. 12B by removing the region Q3 surrounded by the dotted line shown in FIG. 12A by etching in step S303 of FIG. Also by this, since the connection wiring 39 is removed after the step of forming the pressure chamber C, the same effect as in the first embodiment can be obtained.

  In the third embodiment, since the connection wiring 39 is formed outside the cut-out area of the second substrate B (the area inside the cut line CL shown in FIG. 12A), in step S304 in FIG. The connection wiring 39 can also be removed by cutting out. Therefore, according to the third embodiment, since the process of step S303 in FIG. 7 can be omitted, the manufacturing process can be simplified.

<Modification>
Each embodiment illustrated above can be variously modified. Specific modifications are exemplified below. Two or more aspects arbitrarily selected from the following examples can be appropriately combined as long as they do not contradict each other.

(1) In each of the above-described embodiments, the piezoelectric liquid ejecting head 26 using a piezoelectric element that imparts mechanical vibration to the pressure chamber is illustrated as the pressure generating element. However, as the pressure generating element, the pressure chamber is heated by heating. It is also possible to employ a thermal type liquid jet head that uses a heat generating element that generates bubbles inside. Further, the configuration of the plurality of nozzles N in the liquid ejecting head 26 is not limited to the exemplification of each embodiment described above.

(2) The liquid ejecting apparatus 100 exemplified in each of the above-described embodiments can be employed in various apparatuses such as a facsimile apparatus and a copying machine in addition to apparatuses dedicated to printing. However, the application of the liquid ejecting apparatus 100 of the present invention is not limited to printing. For example, a liquid ejecting apparatus that ejects a solution of a coloring material is used as a manufacturing apparatus that forms a color filter of a liquid crystal display device. Further, a liquid ejecting apparatus that ejects a solution of a conductive material is used as a manufacturing apparatus that forms wiring and electrodes of a wiring board.

DESCRIPTION OF SYMBOLS 100 ... Liquid ejecting apparatus, 12 ... Medium, 14 ... Liquid container, 20 ... Control apparatus, 22 ... Conveyance mechanism, 24 ... Transfer mechanism, 242 ... Conveyance body, 244 ... Endless belt, 26 ... Liquid ejecting head, 32 ... Flow path Substrate, 322 ... Supply channel, 324 ... Communication channel, 326 ... Intermediate channel, 34 ... Pressure chamber substrate, 342 ... Opening, 35 ... Pressure generating device, 36 ... Vibration unit, 37 ... Piezoelectric element, 371 ... First Electrode, 372, second electrode, 373, piezoelectric layer, 38, wiring connection board, 384, first wiring, 384a, terminal, 385, second wiring, 385a, one end, 385b, other end, 385c, intermediate portion, 388 ... wiring, 39 ... connection wiring, 40 ... casing, 42 ... concave, 43 ... introduction port, 52 ... nozzle plate, 54 ... vibration absorber, 64 ... wiring member, A ... first substrate, B ... second substrate , C ... pressure chamber, CL ... cutting line, COM ... Motion signal, H1, H2 ... conduction hole, H3 ... conduction groove, 62 ... drive IC, L1 ... first row, L2 ... second row, N ... nozzle, P1 ... first terminal, P2 ... second terminal, R ... Liquid storage chamber, VBS, base voltage, WA, WB, silicon substrate.

Claims (7)

A first substrate on which a pressure generating element having a first electrode, a second electrode, and a piezoelectric layer interposed therebetween is formed, and a connection wiring for connecting the first electrode and the second electrode is formed. Joining the two substrates;
Forming a pressure chamber in the first substrate for generating pressure by the pressure generating element;
After the step of forming the pressure chamber, the method of manufacturing a pressure generating device, including a step of removing the connection wiring and releasing the connection between the first electrode and the second electrode. 2. The method of manufacturing a pressure generating device according to claim 1, wherein the connection wiring is formed in a region overlapping the region of the first substrate where the pressure generating element is formed in the second substrate. The method for manufacturing a pressure generating device according to claim 1, wherein the connection wiring is formed on a surface of the second substrate opposite to the first substrate. The method of manufacturing a pressure generating device according to claim 3, wherein the connection wiring is formed inside a region where the driving IC of the pressure generating element is mounted on the second substrate. The method for manufacturing a pressure generating device according to any one of claims 1 to 3, wherein the connection wiring is formed outside a region of the second substrate cut out from a base material on which the second substrate is formed. The method for manufacturing a pressure generating device according to claim 1, wherein the step of releasing the connection between the first electrode and the second electrode includes a step of removing the connection wiring by etching. 6. The method of manufacturing a pressure generating device according to claim 5, wherein the step of releasing the connection between the first electrode and the second electrode includes a step of removing the connection wiring by cutting out a region of the second substrate from the base material. Method.

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