JP2005271368A - Method of manufacturing liquid jet head and liquid jet head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a liquid jet head capable of comparatively readily and accurately carrying out the electrical coupling of a driver IC to a piezoelectric element and improving an yield, and the liquid jet head. <P>SOLUTION: To provide a method of manufacturing a liquid jet head capable of comparatively readily and accurately carrying out the electrical coupling of a driver IC to a piezoelectric element and improving the yield, and the liquid jet head. This method of manufacturing the liquid jet head comprises a process of forming a piezoelectric element on one face side of a channel forming substrate with a diaphragm therebetween, a process of bonding a protection substrate to the channel forming substrate at the face of the side of the piezoelectric element and mounting the driver IC on the protection substrate, and a process of determining a position of a terminal of an electrode of the piezoelectric element by referencing a first positioning mark formed on the one face of the channel forming substrate and a position of a terminal of the driver IC by referencing a second positioning mark formed on the protection substrate, and connecting the terminals of the piezoelectric element and the driver IC with each other by a wire-bonding method. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method of manufacturing a liquid ejecting head for ejecting liquid and a liquid ejecting head, and in particular, ejects ink from a nozzle opening by pressurizing ink supplied to a pressure generating chamber communicating with the nozzle opening by a piezoelectric element. The present invention relates to an ink jet recording head manufacturing method and an ink jet recording head.

  An ink jet type in which a part of a pressure generating chamber communicating with a nozzle opening for discharging ink is constituted by a vibration plate, and the vibration plate is deformed by a piezoelectric element to pressurize ink in the pressure generating chamber and discharge ink from the nozzle opening. Two types of recording heads have been put into practical use: those using a longitudinal vibration mode piezoelectric actuator that expands and contracts in the axial direction of the piezoelectric element, and those using a flexural vibration mode piezoelectric actuator.

  As the latter ink jet recording head, a piezoelectric element is provided on one side of a flow path forming substrate having a pressure generating chamber, and a reservoir forming substrate having a piezoelectric element holding portion for sealing the piezoelectric element is used as a piezoelectric of the flow path forming substrate. There has been proposed a structure in which an element-side surface is bonded with an adhesive (for example, see Patent Document 1). In addition, such a head includes a lead electrode drawn out from the piezoelectric element to the outside of the piezoelectric element holding portion. The other end portion of the connection wiring having one end portion connected to the terminal portion of the driving IC mounted on the reservoir forming substrate is electrically connected to the terminal portion of the lead electrode by wire bonding. .

  Here, in the manufacture of such an ink jet recording head, the relative position between the flow path forming substrate and the reservoir forming substrate may deviate from the designed relative position. For example, when the flow path forming substrate and the reservoir forming substrate are bonded with an adhesive, there is a case where a so-called bonding shift occurs in which the two substrates are bonded in a state of being shifted in the surface direction of the bonding surface. In addition, in the case of manufacturing a plurality of flow path forming substrate wafers to be a flow path forming substrate and a plurality of reservoir forming substrate wafers to be a reservoir forming substrate by bonding, There are cases where the formation position of the formation substrate is shifted, and even if the wafers are bonded together without adhesion displacement, the relative position between the flow path formation substrate and the reservoir formation substrate may be shifted.

  If the relative position between the flow path forming substrate and the reservoir forming substrate is shifted as described above, the positional relationship between the terminal portion of the drive IC and the terminal portion of the lead electrode is also shifted. When wire bonding is performed between the terminal portions of the drive IC and the lead electrode assuming that the formation substrate is well bonded, there is a problem that a connection failure such as a short circuit occurs due to a displacement of the connection wiring.

  Such a problem is particularly noticeable as the wiring density is increased, and not only when manufacturing an ink jet recording head that ejects ink, but of course other liquids that eject liquid other than ink. It exists in the same way when the ejection head is manufactured.

JP 2003-63000 A (FIG. 1)

  In view of such circumstances, the present invention can make electrical connection between a driving IC and a piezoelectric element relatively easily and with high accuracy, and can improve the yield and the liquid jet head manufacturing method and liquid It is an object to provide an ejection head.

According to a first aspect of the present invention for solving the above problem, a flow path forming substrate in which a pressure generating chamber communicating with a nozzle opening for ejecting liquid is formed, and a diaphragm is provided on one surface side of the flow path forming substrate. Protection provided with a piezoelectric element comprising a lower electrode, a piezoelectric layer, and an upper electrode, and a piezoelectric element holding portion that is bonded to the surface of the flow path forming substrate on the piezoelectric element side to protect the piezoelectric element A method of manufacturing a liquid jet head comprising a substrate and a driving IC mounted on the protective substrate, wherein the piezoelectric element is formed on one surface side of the flow path forming substrate via the diaphragm. Bonding the protective substrate to the surface of the flow path forming substrate on the piezoelectric element side and mounting the driving IC on the protective substrate; and a first step provided on one surface of the flow path forming substrate 1 With reference to the positioning mark, the piezoelectric element The position of the terminal portion of the driving IC is specified, the position of the terminal portion of the driving IC is specified with reference to the second positioning mark provided on the protective substrate, and a wire is provided between each terminal portion of the piezoelectric element and the driving IC. A method of manufacturing a liquid jet head, comprising: a step of bonding connection.
In such a first aspect, whether the relative position between the flow path forming substrate and the protective substrate is deviated by providing the first positioning mark on the flow path forming substrate and providing the second positioning mark on the protective substrate. Regardless of whether the first positioning mark and the second positioning mark are used as a reference, the positional relationship between the piezoelectric element and each terminal portion of the driving IC can be specified. Therefore, at the time of wire bonding connection, the electrical connection between the driving IC and the piezoelectric element can be performed relatively easily and with high accuracy, and the yield can be improved.

According to a second aspect of the present invention, there is provided a flow path forming substrate in which a pressure generating chamber communicating with a nozzle opening for ejecting liquid is formed, and provided on one side of the flow path forming substrate via a vibration plate. A protective substrate provided with a piezoelectric element composed of an electrode, a piezoelectric layer and an upper electrode, a piezoelectric element holding portion that is bonded to the surface of the flow path forming substrate to protect the piezoelectric element, and the protection A method of manufacturing a liquid jet head comprising a driving IC mounted on a substrate, the step of forming the piezoelectric element via the diaphragm on one side of the flow path forming substrate, and the flow path Bonding the protective substrate to the surface of the forming substrate on the piezoelectric element side and mounting the driving IC on the protective substrate; and a first positioning mark provided on the flow path forming substrate or the protective substrate Any of the second positioning marks on the The position of the terminal portion of the electrode of the piezoelectric element and the position of the terminal portion of the drive IC are specified with reference to one mark, and the piezoelectric element is based on the relative position of the first positioning mark and the second positioning mark. And a step of correcting the position of each terminal portion of the driving IC and wire bonding connecting between the piezoelectric element and each terminal portion of the driving IC.
In the second aspect, even if the relative position between the flow path forming substrate and the protective substrate is shifted by providing the first positioning mark on the flow path forming substrate and providing the second positioning mark on the protective substrate. Based on the relative position between the first positioning mark and the second positioning mark, the positional relationship between each terminal portion of the piezoelectric element and the drive IC can be corrected and specified. Therefore, at the time of wire bonding connection, the electrical connection between the driving IC and the piezoelectric element can be performed relatively easily and with high accuracy, and the yield can be improved.

According to a third aspect of the present invention, in the first or second aspect, the method includes a step of forming a lead electrode drawn out from the piezoelectric element to the outside of the piezoelectric element holding portion, and the step of forming the lead electrode. In the method of manufacturing the liquid ejecting head, the first positioning mark is patterned and formed at the same time when the lead electrode is formed.
In the third aspect, the position of the terminal portion of the lead electrode can be specified relatively easily and with high accuracy based on the first positioning mark.

According to a fourth aspect of the present invention, in any one of the first to third aspects, when the drive IC is mounted, the drive IC is placed at a predetermined position on the protective substrate with the second positioning mark as a reference. It is in the manufacturing method of the liquid jet head characterized by mounting.
In the fourth aspect, the position of the terminal portion of the drive IC can be specified relatively easily and with high accuracy based on the second positioning mark.

According to a fifth aspect of the present invention, in any of the first to fourth aspects, in the wire bonding connection step, the wire bonding connection is performed while applying an ultrasonic wave under a heating temperature condition of 100 ° C. or less. And a manufacturing method of the liquid jet head.
In the fifth aspect, the terminal part of the driving IC and the terminal part of the electrode of the piezoelectric element can be reliably connected with a desired bonding strength even in wire bonding connection where the heating condition is relatively low.

According to a sixth aspect of the present invention, there is provided a flow path forming substrate in which a pressure generating chamber communicating with a nozzle opening for injecting a liquid is formed, and provided on one surface side of the flow path forming substrate via a vibration plate. A protective substrate provided with a piezoelectric element composed of an electrode, a piezoelectric layer and an upper electrode, a piezoelectric element holding portion that is bonded to the surface of the flow path forming substrate to protect the piezoelectric element, and the protection A liquid ejecting head including a driving IC mounted on a substrate, wherein a reference for specifying a position of a terminal portion of the electrode of the piezoelectric element when wire bonding is connected on the flow path forming substrate And a second positioning mark serving as a reference for specifying the position of the terminal portion of the driving IC when wire bonding is connected. Liquid characterized by In the injection head.
In the sixth aspect, it is possible to provide a liquid ejecting head in which the driving IC and the piezoelectric element are electrically connected with a desired bonding strength through the connection wiring and have high reliability at a low cost.

Hereinafter, the present invention will be described in detail based on embodiments.
(Embodiment 1)
FIG. 1 is an exploded perspective view of the ink jet recording head according to the first embodiment. FIG. 2 is a plan view of the ink jet recording head according to the first embodiment and its AA ′ cross-sectional view. FIG. 3 is an enlarged plan view of a main part of the ink jet recording head according to the first embodiment. As shown in the figure, the flow path forming substrate 10 is made of a silicon single crystal substrate having a plane orientation (110) in the present embodiment, and one surface thereof is made of silicon dioxide previously formed by thermal oxidation, and has a thickness of 1 to 2 μm. The elastic membrane 50 is provided. The flow path forming substrate 10 is provided with a plurality of pressure generating chambers 12 which are formed by anisotropic etching from the other side and are partitioned by a partition wall 11. Further, on the outer side in the longitudinal direction of the pressure generation chamber 12, a communication portion 13 constituting a part of the reservoir 100 serving as a common ink chamber for each pressure generation chamber 12 is formed. Are communicated with one end in the longitudinal direction via an ink supply path 14, respectively. The cross-sectional area of each ink supply path 14 communicating with one end of each pressure generation chamber 12 is smaller than that of the pressure generation chamber 12, and the flow path resistance of the ink flowing into the pressure generation chamber 12 is constant. keeping.

Further, on the opening surface side of the flow path forming substrate 10, a nozzle plate 20 having a nozzle opening 21 communicating with the vicinity of the end portion of each pressure generating chamber 12 on the side opposite to the ink supply path 14 is provided with an adhesive or It is fixed via a heat welding film or the like. The nozzle plate 20 has a thickness of, for example, 0.01 to 1 mm, a linear expansion coefficient of 300 ° C. or less, for example, 2.5 to 4.5 [× 10 ⁻⁶ / ° C.], glass ceramics, silicon It consists of a single crystal substrate or non-rust steel. Further, the nozzle plate 20 may be formed of a material having substantially the same thermal expansion coefficient as that of the flow path forming substrate 10.

  On the other hand, as described above, the elastic film 50 having a thickness of, for example, about 1.0 μm is formed on the side opposite to the opening surface of the flow path forming substrate 10. For example, an insulator film 55 having a thickness of about 0.4 μm is formed. Further, on the insulator film 55, a lower electrode film 60 having a thickness of, for example, about 0.2 μm, a piezoelectric layer 70 having a thickness of, for example, about 1.0 μm, and a thickness of, for example, about 0 The upper electrode film 80 of .05 μm is laminated to form the piezoelectric element 300. Here, the piezoelectric element 300 refers to a portion including the lower electrode film 60, the piezoelectric layer 70, and the upper electrode film 80. In general, one electrode of the piezoelectric element 300 is used as a common electrode, and the other electrode and the piezoelectric layer 70 are patterned for each pressure generating chamber 12. In addition, here, a portion that is configured by any one of the patterned electrodes and the piezoelectric layer 70 and in which piezoelectric distortion is generated by applying a voltage to both electrodes is referred to as a piezoelectric active portion. In the present embodiment, the lower electrode film 60 is used as a common electrode of the piezoelectric element 300 and the upper electrode film 80 is used as an individual electrode of the piezoelectric element 300. However, there is no problem even if this is reversed for convenience of a drive circuit and wiring. In either case, a piezoelectric active part is formed for each pressure generating chamber. Further, here, the piezoelectric element 300 and the vibration plate that is displaced by driving the piezoelectric element 300 are collectively referred to as a piezoelectric actuator. In the example described above, the elastic film 50, the insulator film 55, and the lower electrode film 60 serve as a diaphragm.

As a material of the piezoelectric layer 70, for example, a relaxor ferroelectric material obtained by adding a metal such as niobium, nickel, magnesium, bismuth or ytterbium to a ferroelectric piezoelectric material such as lead zirconate titanate (PZT). Etc. may be used. The composition may be appropriately selected in consideration of the characteristics and application of the piezoelectric element. For example, PbTiO ₃ (PT), PbZrO ₃ (PZ), Pb (Zr _x Ti _1-x ) O ₃ (PZT) , Pb (Mg _1/3 Nb _2/3 ) O ₃ -PbTiO ₃ (PMN-PT), Pb (Zn _1/3 Nb _2/3 ) O ₃ -PbTiO ₃ (PZN-PT), Pb (Ni _{1 / 3} Nb _2/3 ) O ₃ -PbTiO ₃ (PNN-PT), Pb (In _1/2 Nb _1/2 ) O ₃ -PbTiO ₃ (PIN-PT), Pb (Sc _1/3 Ta _1/2 ) O ₃ -PbTiO ₃ (PST-PT), Pb (Sc _1/3 Nb _1/2 ) O ₃ -PbTiO ₃ (PSN-PT), BiScO ₃ -PbTiO ₃ (BS-PT), BiYbO ₃ -PbTiO ₃ ( BY-PT Etc. The.

  On the flow path forming substrate 10 on which such a piezoelectric element 300 is formed, a protective substrate 30 having a piezoelectric element holding portion 31 capable of ensuring a space that does not hinder its movement in a region facing the piezoelectric element 300 is provided. It is joined via an adhesive. And since the piezoelectric element 300 is formed in the piezoelectric element holding | maintenance part 31, it is protected in the state which hardly receives the influence of an external environment.

  In addition, such a protective substrate 30 is provided with a reservoir portion 32 that constitutes at least a part of the reservoir 100. In this embodiment, the reservoir portion 32 is formed through the protective substrate 30 in the thickness direction and across the width direction of the pressure generation chamber 12, and flows through the communication hole provided in the elastic film 50. Reservoirs 100 that are in communication with the communication portion 13 of the path forming substrate 10 and serve as a common ink chamber for each row of the pressure generating chambers 12 are respectively configured. Examples of such a protective substrate 30 include glass, ceramic materials, metals, resins, and the like, but it is more preferable that the protective substrate 30 be formed of a material that is substantially the same as the coefficient of thermal expansion of the flow path forming substrate 10. In this embodiment, the silicon single crystal substrate made of the same material as the flow path forming substrate 10 is used. In addition, a through hole 33 that penetrates the protective substrate 30 in the thickness direction is provided in a region between the piezoelectric element holding portion 31 and the reservoir portion 32 of the protective substrate 30.

  On the other hand, a wiring pattern 35 is provided on the surface of the protective substrate 30, that is, on the surface opposite to the piezoelectric element holding portion 31 side, as shown in FIG. A driving IC 200 (semiconductor integrated circuit) for driving the piezoelectric element 300 is mounted. Then, the other end portion of the connection wiring 210 made of a bonding wire having one end connected to the terminal portion 200a of the driving IC 200 is connected to the terminal portion 90a of the lead electrode 90 drawn out from each piezoelectric element 300 into the through hole 33 ( Each piezoelectric element 300 and the drive IC 200 are electrically connected to each other. Further, the terminal part 200 a of the driving IC 200 and the terminal part 35 a which is the end of the wiring pattern 35 on the protective substrate 30 are similarly wire-bonded by the connection wiring 210.

  Here, in the present embodiment, the region exposed in the through hole of the protective substrate 30, that is, in the vicinity of the terminal portion 90 a of the lead electrode 90 on one surface of the flow path forming substrate 10, for example, A cross-shaped first positioning mark 10a is provided. Therefore, the first positioning mark 10 a is exposed in the through hole 33 together with the terminal portion 90 a of the lead electrode 90 in a state where the flow path forming substrate 10 and the protective substrate 30 are joined. On the other hand, on the protective substrate 30, for example, a cross-shaped second positioning mark 30 a is provided in the vicinity of the terminal portion 35 a of the wiring pattern 35. The wire bonding connection is performed based on the first positioning mark 10a and the second positioning mark 30a, which will be described in detail later. As a result, the liquid ejecting head in which the driving IC 200 and the lead electrode 90 are electrically connected with the desired bonding strength by the connection wiring 210 and has high reliability can be provided at low cost.

  In addition, a compliance substrate 40 including a sealing film 41 and a fixing plate 42 is bonded to a region corresponding to the reservoir portion 32 of the protective substrate 30. Here, the sealing film 41 is made of a material having low rigidity and flexibility (for example, a polyphenylene sulfide (PPS) film having a thickness of 6 μm). The sealing film 41 seals one surface of the reservoir portion 32. It has been stopped. The fixing plate 42 is made of a hard material such as metal (for example, stainless steel (SUS) having a thickness of 30 μm). Since the region of the fixing plate 42 facing the reservoir 100 is an opening 43 that is completely removed in the thickness direction, one surface of the reservoir 100 is sealed only with a flexible sealing film 41. Has been.

  The ink jet recording head of the present embodiment described above takes in ink from an ink supply means (not shown), fills the interior from the reservoir 100 to the nozzle opening 21, and then generates pressure according to the drive signal from the drive IC 200. By applying a driving voltage between the lower electrode film 60 and the upper electrode film 80 corresponding to each chamber 12 and displacing the piezoelectric element 300 and the diaphragm, the pressure in each pressure generating chamber 12 is increased, and the nozzle opening 21 ejects ink.

  Here, a method of manufacturing such an ink jet recording head will be described with reference to FIGS. 4 to 6 are sectional views of the pressure generating chamber 12 in the longitudinal direction. First, as shown in FIG. 4A, a flow path forming substrate wafer 110 made of a silicon wafer and serving as a plurality of flow path forming substrates 10 is thermally oxidized in a diffusion furnace at about 1100 ° C., and an elastic film 50 is formed on the surface thereof. A silicon dioxide film 51 is formed. In this embodiment, a silicon wafer having a relatively thick film thickness of about 625 μm and a high rigidity is used as the flow path forming substrate wafer 110.

  Next, as shown in FIG. 4B, an insulator film 55 made of zirconium oxide is formed on the elastic film 50 (silicon dioxide film 51). Next, as shown in FIG. 4C, for example, a lower electrode film 60 made of at least platinum and iridium is formed on the entire surface of the insulator film 55 by sputtering or the like, and then the lower electrode film 60 is patterned into a predetermined shape. To do.

  Next, as shown in FIG. 4D, for example, a piezoelectric layer 70 made of lead zirconate titanate (PZT) or the like and an upper electrode film 80 made of iridium, for example, are formed on the entire surface of the flow path forming substrate 10. Then, as shown in FIG. 5A, the piezoelectric layer 300 is formed by patterning the piezoelectric layer 70 and the upper electrode film 80 in regions facing the pressure generation chambers 12.

  Next, as shown in FIG. 5B, lead electrodes 90 are formed. Specifically, a metal layer 91 made of, for example, gold (Au) or the like is formed over the entire surface of the flow path forming substrate wafer 110. Thereafter, for example, the lead electrode 90 is formed by patterning the metal layer 91 for each piezoelectric element 300 through a mask pattern (not shown) made of a resist or the like. Also, for example, a cross-shaped first positioning mark 10a is formed in a region of the flow path forming substrate wafer 110 facing a through hole 33 of a protective substrate wafer 130 described later (see FIG. 3). In the present embodiment, the first positioning mark 10a is formed at the same time when the metal layer 91 is patterned.

  Next, as shown in FIG. 5C, a protective substrate wafer 130 made of a silicon wafer and serving as a plurality of protective substrates 30 is bonded to the flow path forming substrate wafer 110 on the piezoelectric element 300 side by an adhesive. Here, the piezoelectric element holding portion 31 is provided in advance on the bonding surface side of the protective substrate wafer 130 with the flow path forming substrate wafer 110, and the portion of the lead electrode 90 facing the terminal portion 90 a has a through hole 33. Is provided in advance. A wiring pattern 35 made of gold (Au) is provided in advance on the protective substrate wafer 130, that is, on the surface opposite to the bonding surface with the flow path forming substrate wafer 110. In the vicinity of the terminal portion 35a of the wiring pattern 35, for example, a cross-shaped second positioning mark 30a is provided (see FIG. 3). The second positioning mark 30a may be formed simultaneously with the wiring pattern 35 or may be formed separately from the wiring pattern 35. In the present embodiment, the second positioning mark 30a is formed simultaneously with the wiring pattern 35. Since the protective substrate wafer 130 has a thickness of, for example, about 400 μm, the rigidity of the flow path forming substrate wafer 110 is remarkably improved by bonding the protective substrate wafer 130.

  Next, as shown in FIG. 5 (d), after the flow path forming substrate wafer 110 is polished to a certain thickness, the flow path forming substrate wafer 110 is further etched by wet etching with fluorinated nitric acid. Make it thick. For example, in this embodiment, the flow path forming substrate wafer 110 is etched so as to have a thickness of about 70 μm.

  Next, as shown in FIG. 6A, a mask film 52 made of, for example, silicon nitride (SiN) is newly formed on the flow path forming substrate wafer 110 and patterned into a predetermined shape. Then, the flow path forming substrate wafer 110 is anisotropically etched through the mask film 52, whereby, as shown in FIG. 13 and the ink supply path 14 are formed. Next, as shown in FIG. 6C, the nozzle plate 20 is bonded to the flow path forming substrate 10 via the mask film 52, and the second positioning mark 30 a on the protective substrate 30 is used as a reference on the protective substrate 30. After the driving IC 200 is mounted and the compliance substrate 40 is bonded, the driving IC 200 and each piezoelectric element 300 are connected via the connection wiring 210 by wire bonding. Here, the second positioning mark 30a is used as a reference when the driving IC 200 is mounted. However, the present invention is not limited to this, and the wiring pattern 35 or the like can be provided if it can be mounted at a predetermined position on the protective substrate 30, for example. It is good also as a standard.

  Here, the wire bonding connection method of the present embodiment will be described in detail with reference to FIG. In connecting the driving IC 200 and each piezoelectric element 300 via the connection wiring 210, the position (position) of the terminal portion 90 a of the lead electrode 90 is determined based on the design data of the flow path forming substrate wafer 110 and the protective substrate wafer 130. Data) and the position (position data) of the terminal portion 200a of the driving IC 200 are obtained in advance. In the present embodiment, as described in the above-described manufacturing process, the first positioning mark 10a is formed by patterning simultaneously with the lead electrode 90, and the second positioning mark 30a is used as a reference on the protective substrate wafer 130. The driving IC 200 is mounted on the board. Therefore, the error between the design data for each wafer and the position data of the terminal portions 200a and 90a of the actual driving IC 200 and the lead electrode 90 is extremely small.

  Then, wire bonding connection is made based on the position data of the terminal portion 90 a of the lead electrode 90 and the position data of the terminal portion 200 a of the drive IC 200. Specifically, the capillary (not shown) is moved from the second positioning mark 30a to the terminal portion 200a of the driving IC 200 based on the position data of the terminal portion 200a of the driving IC 200, and first bonding (ball bonding) is performed. Next, the capillary is moved from the first positioning mark 10a to the terminal portion 90a of the lead electrode 90a based on the position data of the terminal portion 90a of the lead electrode 90, and second bonding is performed. Accordingly, whether or not the relative position of the flow path forming substrate wafer 110 and the protective substrate wafer 130 is shifted in the surface direction of the bonding surface, or the formation of the flow path forming substrate 10 and the protective substrate 30 in one wafer. Regardless of whether or not the positions are varied, the positional relationship between the terminal portions 200a and 90a of the drive IC 200 and the lead electrode 90 can be specified with reference to the first positioning mark 10a and the second positioning mark 30a. it can. Therefore, the electrical connection between the driving IC 200 and the lead electrode 90 (piezoelectric element 300) can be performed relatively easily and with high accuracy, and the yield can be improved.

  Here, in wire bonding connection, in order to ensure a desired bonding strength, the heating temperature is generally about 150 to 200 ° C. or above this range. However, in the above-described head structure, when wire bonding is performed at such a relatively high heating temperature, the head is destroyed by heat. For this reason, in the present invention, the heating temperature at the time of wire bonding connection is about 100 ° C. or less, preferably about 70 ° C. or less. In order to ensure the desired bonding strength even at such a low temperature, heat and ultrasonic waves are used. Wire bonding is performed while using it together. In such wire bonding, if the bonding position is slightly shifted, the bonding strength is extremely lowered. However, in the manufacturing method of the present embodiment, the positions of the terminal portions 200a and 90a of the drive IC 200 and the lead electrode 90 are specified in advance, so that it is possible to prevent the bonding strength from being lowered. That is, according to the manufacturing method of the present embodiment, the terminal portion 200a of the drive IC 200 and the terminal portion 90a of the lead electrode 90 are reliably connected with a desired bonding strength even in the case of wire bonding connection at a relatively low temperature. Can do.

  Thereafter, although not shown, unnecessary portions of the outer peripheral edge portions of the flow path forming substrate wafer 110 and the protective substrate wafer 130 are removed by cutting, for example, by dicing, and the flow path forming substrate wafer 110 and the like are removed. The ink jet recording head of the present embodiment is obtained by dividing the flow path forming substrate 10 or the like having one chip size as shown in FIG.

  In the first embodiment described above, an example of a method for wire bonding connection using the first positioning mark 10a and the second positioning mark 30a has been described, but the present invention is not limited to this.

(Embodiment 2)
In the present embodiment, when bonding connection is performed, when the capillary is moved to the terminal part of the driving IC and the terminal part of the lead electrode with reference to the first positioning mark, the position data of the terminal part of the driving IC is first By correcting based on the relative position between the positioning mark and the second positioning mark, the terminal portions of the drive IC and the lead electrode are connected to each other.

  Specifically, for example, based on the design data, the position data of the lead electrode and each terminal portion of the driving IC with reference to the first positioning mark, and the relative position data of the first positioning mark and the second positioning mark (design Relative position data) is obtained. Then, after joining the flow path forming substrate wafer and the protective substrate wafer, relative position data (actual relative position data) between the first positioning mark on the flow path forming substrate and the second positioning mark on the protective substrate is obtained. From the actual relative position data and the design relative position data obtained by measurement, the amount of displacement of the first positioning mark and the second positioning mark, that is, the amount of displacement of the relative position between each flow path forming substrate and each protective substrate. Ask for. Then, when the capillary is moved from the first positioning mark on the flow path forming substrate to the terminal portion of the driving IC on the protective substrate, the position data of the terminal portion of the driving IC is corrected based on this positional deviation amount. Thereby, even when the relative position between the flow path forming substrate wafer and the protective substrate wafer is deviated, each of the piezoelectric element and the drive IC is determined based on the relative position between the first positioning mark and the second positioning mark. Since the positional relationship of the terminal portions can be corrected and specified, the same effect as that of the first embodiment described above can be obtained.

  As described above, in this embodiment, when performing bonding connection, the capillary is moved with reference to the first positioning mark. However, the present invention is not limited to this, and the capillary is moved with reference to the second positioning mark. You may do it. Specifically, design relative position data based on the second positioning mark is obtained, and the amount of positional deviation between the first positioning mark and the second positioning mark is obtained from the design relative position data and the actual relative position data. Thereafter, when the capillary is moved from the second positioning mark on the protective substrate to the terminal portion of the lead electrode on the flow path forming substrate, the position data of the terminal portion of the lead electrode is corrected based on the amount of this positional deviation. Also good.

  Further, the third positioning mark may be provided on either the flow path forming substrate wafer or the protective substrate wafer. In this case, by using the first to third positioning marks, not only the shift amount of the parallel movement between the flow path forming substrate wafer and the protective substrate wafer but also the shift amount in the rotation direction is corrected to correct the wire. Bonding connection can be made.

(Other embodiments)
As mentioned above, although embodiment of this invention was described, of course, this invention is not limited to the above-mentioned embodiment. In the first embodiment described above, an example in which the first positioning mark 10a and the second positioning mark 30a are cross-shaped has been described. However, the present invention is not limited to this. 2 It is good also as a shape which can recognize the position of a positioning mark, for example, a rectangle etc.

  In the first embodiment described above, the case where the lead electrode 90 drawn from the surface of the upper electrode film 80 and the connection wiring 210 are electrically connected has been described. However, the present invention is not limited to this. The present invention may be applied to the case where a lead electrode is drawn into the through hole of the protective substrate and the lead electrode and the connection wiring are electrically connected.

  Furthermore, in the first embodiment described above, the thin film type ink jet recording head manufactured by applying the film forming and lithography processes is taken as an example, but the present invention is of course not limited thereto. The present invention can be applied to a thick film type ink jet recording head formed by such a method.

  In Embodiment 1 described above, the ink jet recording head has been described as an example of the liquid ejecting head of the present invention. However, the basic configuration of the liquid ejecting head is not limited to the above-described configuration. The present invention covers a wide range of liquid ejecting heads, and can naturally be applied to those ejecting liquids other than ink. Other liquid ejecting heads include, for example, various recording heads used in image recording apparatuses such as printers, color material ejecting heads used in the manufacture of color filters such as liquid crystal displays, organic EL displays, and FEDs (surface emitting displays). Examples thereof include an electrode material ejection head used for electrode formation, a bioorganic matter ejection head used for biochip production, and the like.

FIG. 3 is an exploded perspective view of the recording head according to the first embodiment. 2A and 2B are a plan view and a cross-sectional view of the recording head according to the first embodiment. FIG. 3 is an enlarged plan view of a main part of the recording head according to the first embodiment. 5 is a cross-sectional view illustrating a manufacturing process of the recording head according to Embodiment 1. FIG. 5 is a cross-sectional view illustrating a manufacturing process of the recording head according to Embodiment 1. FIG. 5 is a cross-sectional view illustrating a manufacturing process of the recording head according to Embodiment 1. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Flow path formation board, 12 Pressure generation chamber, 13 Communication part, 14 Ink supply path, 20 Nozzle plate, 21 Nozzle opening, 30 Protection board, 31 Piezoelectric element holding part, 32 Reservoir part, 35 Wiring pattern, 40 Compliance board, DESCRIPTION OF SYMBOLS 50 Elastic film, 60 Lower electrode film, 70 Piezoelectric layer, 80 Upper electrode film, 90 Lead electrode, 90a Terminal part, 100 Reservoir, 110 Flow path formation substrate wafer, 130 Protection substrate wafer, 200 Drive IC, 200a terminal Part, 210 connection wiring, 300 piezoelectric element

Claims (6)

A flow path forming substrate in which a pressure generating chamber communicating with a nozzle opening for ejecting liquid is formed, and a lower plate, a piezoelectric layer, and an upper electrode provided on one surface side of the flow path forming substrate via a vibration plate A protective element provided with a piezoelectric element holding portion that is bonded to the surface of the flow path forming substrate on the piezoelectric element side and protects the piezoelectric element, and a drive IC mounted on the protective substrate; A method of manufacturing a liquid jet head comprising:
Forming the piezoelectric element on one surface side of the flow path forming substrate via the vibration plate, bonding the protective substrate to the surface of the flow path forming substrate on the piezoelectric element side, and on the protective substrate The step of mounting the driving IC and the position of the terminal portion of the electrode of the piezoelectric element are specified on the basis of the first positioning mark provided on one surface of the flow path forming substrate and provided on the protective substrate. And a step of specifying the position of the terminal portion of the driving IC with reference to the second positioning mark and wire bonding connection between the piezoelectric element and each terminal portion of the driving IC. Manufacturing method. A flow path forming substrate in which a pressure generating chamber communicating with a nozzle opening for ejecting liquid is formed, and a lower plate, a piezoelectric layer, and an upper electrode provided on one surface side of the flow path forming substrate via a vibration plate A protective element provided with a piezoelectric element holding portion that is bonded to the surface of the flow path forming substrate on the piezoelectric element side and protects the piezoelectric element, and a drive IC mounted on the protective substrate; A method of manufacturing a liquid jet head comprising:
Forming the piezoelectric element on one surface side of the flow path forming substrate via the vibration plate, bonding the protective substrate to the surface of the flow path forming substrate on the piezoelectric element side, and on the protective substrate The electrode of the piezoelectric element with reference to either the step of mounting the driving IC and the first positioning mark provided on the flow path forming substrate or the second positioning mark provided on the protective substrate The position of the terminal portion of the driving IC and the position of the terminal portion of the driving IC are specified, and the positions of the terminal portions of the piezoelectric element and the driving IC are determined based on the relative positions of the first positioning mark and the second positioning mark. And a step of correcting and connecting each terminal portion of the piezoelectric element and the driving IC by wire bonding. 3. The method according to claim 1, further comprising the step of forming a lead electrode drawn out from the piezoelectric element to the outside of the piezoelectric element holding portion, and in the step of forming the lead electrode, the lead electrode is formed when the lead electrode is formed. A method of manufacturing a liquid jet head, wherein the first positioning mark is patterned and formed simultaneously. The liquid ejecting head according to claim 1, wherein when the driving IC is mounted, the driving IC is mounted at a predetermined position on the protective substrate with the second positioning mark as a reference. Manufacturing method. 5. The method of manufacturing a liquid jet head according to claim 1, wherein in the wire bonding connection step, the wire bonding connection is performed while applying an ultrasonic wave under a heating temperature condition of 100 ° C. or less. A flow path forming substrate in which a pressure generating chamber communicating with a nozzle opening for ejecting liquid is formed, and a lower plate, a piezoelectric layer, and an upper electrode provided on one surface side of the flow path forming substrate via a vibration plate A protective element provided with a piezoelectric element holding portion that is bonded to the surface of the flow path forming substrate on the piezoelectric element side and protects the piezoelectric element, and a drive IC mounted on the protective substrate; A liquid jet head comprising:
A first positioning mark serving as a reference for specifying the position of the terminal portion of the electrode of the piezoelectric element at the time of wire bonding connection is provided on the flow path forming substrate, and a wire is provided on the protective substrate. 2. A liquid ejecting head, comprising: a second positioning mark serving as a reference for specifying a position of a terminal portion of the driving IC at the time of bonding connection.

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