JP2009214522A - Liquid jet head, method of manufacturing liquid jet head, and liquid jet device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid jet head whose durability and reliability are enhanced by strongly joining a channel forming substrate and a reservoir forming substrate, a method for manufacturing the head, and a liquid jetting device. <P>SOLUTION: The liquid jet head has the channel forming substrate 10 forming a pressure generation chamber communicating with a nozzle opening for jetting a liquid and a communication section 13 for communicating with the pressure generation chamber, a piezoelectric element provided in one side of the channel forming substrate 10, a lead electrode made of a substrate layer and a metal layer and led out from the piezoelectric element, a reservoir forming substrate 30 having a reservoir section 31 forming a part of a reservoir by being joined to the piezoelectric element side face of the channel forming substrate 10 via an adhesion layer 35 and communicating with the communication section 13, a discontinuous metal layer 190 made up of a base layer 91 and a metal layer 92 discontinuous from the lead electrode is provided in the periphery of opening section of the communication section 31 of the channel forming substrate 10. In the discontinuous metal layer 190, the end near the communication section 13 of the base layer 91 projects from the communication section 13 side end of the metal layer 92, and the top face of the communication section side end of the base layer 91 is joined to the adhesion layer 35. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

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

  As an ink jet recording head that is a liquid ejecting head, for example, a flow path forming substrate in which a pressure generation chamber communicating with a nozzle opening and a communication portion communicating with the pressure generation chamber are formed, and one of the flow path forming substrates is provided. A piezoelectric element formed on the surface side, and a reservoir forming substrate having a reservoir portion that is joined to a surface of the flow path forming substrate on the piezoelectric element side and forms a part of the reservoir together with the communication portion. In some cases, the lead electrode drawn from the piezoelectric element is bonded to the reservoir forming substrate via a discontinuous underlayer and a metal layer (discontinuous metal layer) (see, for example, Patent Document 1).

JP 2006-044083 A

  In the ink jet recording head having such a configuration, there is a problem that it is difficult to obtain sufficient adhesive strength between the flow path forming substrate and the reservoir forming substrate. When sufficient adhesive strength cannot be obtained, the durability of the ink jet recording head is lowered. Further, when the reservoir is filled with ink during actual driving, there is a problem that the base layer and the metal layer come into contact with the ink and the interface between the base layer and the metal layer is easily peeled off.

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

  The present invention has been made in view of such circumstances, and a liquid ejecting head improved in durability and reliability by firmly joining a flow path forming substrate and a reservoir forming substrate, a manufacturing method thereof, and a liquid It aims at providing an injection device.

An aspect of the present invention that solves the above problems includes a flow path forming substrate in which a pressure generation chamber that communicates with a nozzle opening that ejects liquid and a communication portion that communicates with the pressure generation chamber, A piezoelectric element provided on one surface side, a lead electrode made of a base layer and a metal layer, and drawn out from the piezoelectric element, and joined to the surface on the piezoelectric element side of the flow path forming substrate via an adhesive layer. A reservoir forming substrate having a reservoir portion that communicates with the reservoir and forms a part of the reservoir, and the base layer that is discontinuous from the lead electrode is formed on the periphery of the opening of the communicating portion of the flow path forming substrate. A discontinuous metal layer made of the metal layer is provided, and the discontinuous metal layer has an end portion on the communication portion side of the base layer protruding from an end portion on the communication portion side of the metal layer, and the communication portion of the base layer. The upper surface of the end of the side is joined to the adhesive layer A liquid-jet head characterized by that.
In this aspect, since the upper surface of the end portion of the base layer of the discontinuous metal layer provided at the peripheral edge of the opening of the reservoir portion of the flow path forming substrate is joined to the adhesive layer, the flow path forming substrate and the reservoir are formed. The durability of the head and the reliability can be improved by firmly bonding to the substrate. Further, it is possible to prevent the bonding height between the flow path forming substrate and the reservoir forming substrate from being varied, and it is possible to prevent problems caused by excess adhesive.

  Moreover, it is preferable to use gold as a material of the metal layer. The present invention is particularly effective in a head structure using gold for the lead electrode.

  Moreover, it is preferable to use one selected from the group consisting of nickel, chromium and a nickel chromium compound as the material of the underlayer. According to this, the flow path forming substrate and the reservoir forming substrate are more firmly bonded, and the durability and reliability of the head can be improved.

  Here, it is preferable that the end surface of the discontinuous metal layer on the communication portion side is sealed with the adhesive layer. According to this, even if the reservoir portion and the communication portion are filled with ink, the end surfaces of the base layer and the metal layer do not contact the ink, and there is no possibility that the base layer and the metal layer are separated. For this reason, durability and reliability of the head can be further improved.

  According to another aspect of the invention, there is provided a liquid ejecting apparatus including the liquid ejecting head as described above. In this aspect, it is possible to provide a liquid ejecting apparatus in which the flow path forming substrate and the reservoir forming substrate are firmly joined to improve durability and reliability.

Furthermore, according to another aspect of the present invention, a piezoelectric element is formed on one side of a flow path forming substrate in which a pressure generation chamber communicating with a nozzle opening for ejecting liquid and a communication portion communicating with the pressure generation chamber are formed. A step of forming a metal layer on the surface of the flow path forming substrate on the piezoelectric element side via a base layer, the base layer in a region corresponding to the piezoelectric element and a region corresponding to the communicating portion, and Removing the metal layer to form a lead electrode drawn from the piezoelectric element and forming the discontinuous metal layer composed of the base layer and the metal layer discontinuous with the lead electrode; and the flow path Bonding a reservoir forming substrate having a reservoir portion that communicates with the communicating portion and forms a part of the reservoir to a surface of the forming substrate on the piezoelectric element side via an adhesive layer, and the discontinuous metal layer Before forming the The discontinuous metal layer is formed so that an end portion on the side where the communicating portion of the base layer is formed protrudes from an end portion on the side where the communicating portion of the metal layer is formed, and the flow path forming substrate and the reservoir In the method of manufacturing a liquid jet head, the upper surface of the end portion on the side where the communicating portion of the base layer is formed and the adhesive layer are bonded when the formation substrate is bonded.
In such an aspect, since the upper surface of the end portion of the base layer of the discontinuous metal layer is formed so as to be bonded to the adhesive layer, the flow path forming substrate and the reservoir forming substrate are firmly bonded, so that durability and reliability are ensured. It is possible to manufacture a head with improved resistance. In addition, it is possible to prevent the bonding height from being varied, and it is possible to prevent problems caused by excess adhesive.

Hereinafter, the present invention will be described in detail based on embodiments.
FIG. 1 is an exploded perspective view showing a schematic configuration of an ink jet recording head which is an example of a liquid jet head according to the present embodiment, and FIG. 2 is a plan view of FIG. . FIG. 8 is an enlarged sectional view of the vicinity of the reservoir.

  As shown in the drawing, in the present embodiment, the flow path forming substrate 10 is made of a silicon single crystal substrate, and an elastic film 50 made of silicon dioxide is previously formed on one surface thereof by thermal oxidation. In the flow path forming substrate 10, pressure generation chambers 12 partitioned by a plurality of partition walls 11 are arranged in parallel in the width direction (short direction). In addition, an ink supply path 14 and a communication path 15 are partitioned by a partition wall 11 on one end side in the longitudinal direction of the pressure generating chamber 12 of the flow path forming substrate 10. Further, a communication portion 13 that communicates with each communication path 15 is provided outside the communication path 15. As will be described in detail later, a reservoir forming substrate 30 that is a bonding substrate is bonded to the surface of the flow path forming substrate 10 on the elastic film 50 side, and the communication portion 13 is provided in the first reservoir forming substrate 30. A part of the reservoir 100 that is a common ink chamber of the pressure generation chambers 12 is configured to communicate with the reservoir portion 31 that is a through hole of each of the pressure generation chambers 12. That is, in the present embodiment, the pressure generation chamber 12, the ink supply path 14, the communication path 15, and the communication portion 13 are provided as liquid flow paths formed on the flow path forming substrate 10.

  On the opening surface side of the flow path forming substrate 10, a nozzle plate 20 having a nozzle opening 21 communicating with each pressure generating chamber 12 is fixed by an adhesive, a heat welding film, or the like. The nozzle plate 20 is made of, for example, glass ceramics, a silicon single crystal substrate, or stainless steel.

  On the other hand, the elastic film 50 is formed on the side opposite to the opening surface of the flow path forming substrate 10 as described above, and the insulator film 55 is formed on the elastic film 50. Further, a piezoelectric element 300 composed of a lower electrode film 60, a piezoelectric layer 70, and an upper electrode film 80 is formed on the insulator film 55. 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. Further, here, the piezoelectric element 300 and a diaphragm that is displaced by driving the piezoelectric element 300 are collectively referred to as an actuator. The diaphragm is a portion that constitutes one surface of the pressure generating chamber 12 and is deformed by driving the piezoelectric element 300. In the present embodiment, the elastic film 50, the insulator film 55, and the lower electrode film 60 function as a diaphragm, but of course not limited to this, for example, without providing the elastic film 50 and the insulator film 55. Only the lower electrode film 60 may act as a diaphragm. Further, the piezoelectric element 300 itself may substantially serve as a diaphragm.

  Further, the lead electrode 90 is drawn out from the upper electrode film 80 of each piezoelectric element 300, and a voltage is selectively applied to each piezoelectric element 300 via the lead electrode 90. The lead electrode 90 includes a base layer 91 made of, for example, nickel chrome (NiCr) and a metal layer 92 formed on the base layer 91 and made of, for example, gold (Au). The underlayer 91 serves as an underlayer for bringing the metal layer 92 and the insulator film 55 and the like into close contact with each other, and prevents the metals forming the upper electrode film 80 and the metal layer 92 from chemically reacting with each other. It serves as a barrier layer. Here, the main material of the metal layer 92 is not particularly limited as long as it is a material having a relatively high conductivity. In this embodiment, gold (Au) is used, but in addition, for example, platinum (Pt) , Aluminum (Al), and copper (Cu). Further, the material of the base layer 91 may be any material that has adhesion to the metal layer 92 and adhesion to the adhesive layer 35. Specifically, titanium (Ti), titanium tungsten compound (TiW) , Nickel (Ni), chromium (Cr), or nickel chromium compound (NiCr).

  Further, a discontinuous metal layer which is made of the same material as the base layer 91 and the metal layer 92 constituting the lead electrode 90 but is discontinuous with the lead electrode 90 is formed at the opening peripheral edge of the communication portion 13 of the flow path forming substrate 10. 190 is provided. Then, on the flow path forming substrate 10 on which the piezoelectric element 300 is formed, the reservoir forming substrate 30 in which the reservoir portion 31 is provided in a region facing the communication portion 13 is bonded with, for example, an epoxy adhesive. Joined by layer 35. As described above, since the discontinuous metal layer 190 is provided in the adhesion region with the reservoir forming substrate 30, the height of the adhesion region on the lead electrode 90 side does not vary, and excess adhesive is removed. It is possible to prevent problems due to outflow.

  Here, as shown in FIG. 8, the elastic film 50 is formed with an opening 52 having the same size as the opening of the reservoir portion 31 of the reservoir forming substrate 30, and the insulator film 55 has a reservoir formation. An opening 56 larger than the opening of the reservoir portion 31 of the substrate 30 is formed. Then, the base layer 91 of the discontinuous metal layer 190 is provided so as to cover the end surfaces and the upper end surfaces (on the reservoir forming substrate 30 side) of the openings 56 of the elastic film 50 and the insulator film 55. The end portion of the base layer 91 on the communication portion 13 side protrudes from the end portion of the metal layer 92 on the communication portion 13 side, and the upper surface is joined to the adhesive layer 35. Thereby, the reservoir forming substrate 30 and the flow path forming substrate 10 are firmly bonded. In the present embodiment, since the area where the base layer 91 and the adhesive layer 35 are joined is increased, the adhesion strength is particularly high.

  Further, the end surfaces of the discontinuous metal layer 190 on the side of the communicating portion 13 of the metal layer 92 and the base layer 91 are covered with the adhesive layer 35 and are in a so-called sealed state. For this reason, even if the reservoir 31 and the communication portion 13 are filled with ink during actual driving, the end surfaces of the base layer 91 and the metal layer 92 of the discontinuous metal layer 190 do not contact the ink, and the base layer 91 There is no possibility that the metal layer 92 peels off.

  As described above, the reservoir unit 31 communicates with the communication unit 13 of the flow path forming substrate 10 to constitute the reservoir 100 serving as a common ink chamber for the pressure generation chambers 12. The communication portion 13 may be configured as a plurality of communication portions corresponding to the plurality of pressure generating chambers 12 instead of being integrally formed as shown in FIG. In this case, the reservoir 100 includes only the reservoir portion 31 formed on the reservoir forming substrate 30.

  In addition, the reservoir forming substrate 30 is provided with a piezoelectric element holding portion 32 having a space that does not hinder the movement of the piezoelectric element 300 in a region facing the piezoelectric element 300. In addition, the piezoelectric element holding part 32 should just have a space of the grade which does not inhibit the motion of the piezoelectric element 300, and the said space may be sealed or may not be sealed. Alternatively, the communication portion 13 of the flow path forming substrate 10 may be divided into a plurality of pressure generation chambers 12 and only the reservoir portion 31 may be used as the reservoir. That is, only the pressure generation chamber 12 and the ink supply path 14 may be formed on the flow path forming substrate 10. As the reservoir forming substrate 30, it is preferable to use a material substantially the same as the coefficient of thermal expansion of the flow path forming substrate 10, for example, glass or ceramic material.

  A drive circuit 120 for driving the piezoelectric element 300 is mounted on the reservoir forming substrate 30. For example, a circuit board or a semiconductor integrated circuit (IC) can be used as the drive circuit 120. The drive circuit 120 and the lead electrode 90 are electrically connected via a connection wiring 121 made of a conductive wire such as a bonding wire.

  A compliance substrate 40 including a sealing film 41 and a fixing plate 42 is bonded to a region corresponding to the reservoir portion 31 of the reservoir forming substrate 30. The sealing film 41 is made of a material having low rigidity and flexibility, and one surface of the reservoir portion 31 is sealed by the sealing film 41. The fixing plate 42 is made of a hard material such as metal. Since the region of the fixing plate 42 facing the reservoir 100 is an opening 43 that is completely removed in the thickness direction, one surface of the reservoir 100 is sealed only with a flexible sealing film 41. Has been.

  In such an ink jet recording head I of the present embodiment, ink is taken in from an external ink supply means (not shown), filled with ink from the reservoir 100 to the nozzle opening 21, and then in accordance with a recording signal from the drive circuit 120. Then, a voltage is applied between each of the lower electrode film 60 and the upper electrode film 80 corresponding to the pressure generation chamber 12 to bend and deform the elastic film 50, the insulator film 55, the lower electrode film 60, and the piezoelectric layer 70. As a result, the pressure in each pressure generating chamber 12 increases and ink droplets are ejected from the nozzle openings 21.

  Hereinafter, a method for manufacturing such an ink jet recording head will be described with reference to FIGS. 3 to 7 are cross-sectional views in the longitudinal direction of the pressure generation chamber of the flow path forming substrate wafer.

First, as shown in FIG. 3A, a channel forming substrate wafer 110 which is a silicon wafer is thermally oxidized in a diffusion furnace at about 1100 ° C., and a silicon dioxide film 51 constituting an elastic film 50 is formed on the surface thereof. To do. Next, as shown in FIG. 3B, an insulator film 55 made of zirconium oxide is formed on the elastic film 50 (silicon dioxide film 51). Specifically, after forming a zirconium (Zr) layer on the elastic film 50 (silicon dioxide film 51) by, for example, sputtering, the zirconium layer is thermally oxidized in a diffusion furnace at 500 to 1200 ° C., for example. Thus, the insulator film 55 made of zirconium oxide (ZrO ₂ ) is formed.

  Next, as shown in FIG. 3C, after the lower electrode film 60 is formed by stacking platinum and iridium on the insulator film 55, for example, the lower electrode film 60 is patterned into a predetermined shape.

  4A, 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 flow path forming substrate wafer 110. As shown in FIG. 4B, the piezoelectric element 300 is formed by patterning the piezoelectric layer 70 and the upper electrode film 80 in a region facing each pressure generating chamber 12. The method for forming the piezoelectric layer 70 is not particularly limited. For example, in this embodiment, a so-called sol in which a metal organic substance is dissolved and dispersed in a solvent is applied, dried, gelled, and further fired at a high temperature. The piezoelectric layer 70 was formed by using a so-called sol-gel method for obtaining a piezoelectric layer 70 made of an oxide.

  Next, as shown in FIG. 4C, patterning is performed by ion milling to form an opening 56 in the insulator film 55 and an opening 52 in the elastic film 50. At this time, when performing ion milling of the insulator film 55 and the elastic film 50, although not shown, the regions other than the openings 56 and 52 are protected with a mask such as a resist so that they are not etched by ion milling. The opening 56 and the opening 52 are made equal to or larger than the opening of the reservoir portion 31 of the reservoir forming substrate 30 to be bonded later. In the present embodiment, the opening 56 is made larger than the opening 52 as shown in FIG. As described above, by forming openings in the elastic film 50 and the insulator film 55, when forming the base layer 91 to be described later, the end surfaces and the upper ends of the elastic film 50 and the insulator film 55 are placed on the base layer 91. The area where the base layer 91 and the adhesive layer 35 are joined can be increased to increase the adhesion strength.

  As shown in FIG. 5A, first, a base layer 91 made of nickel chromium (NiCr) is formed over the entire surface of the flow path forming substrate wafer 110, and, for example, gold (Au) is formed on the base layer 91. ) Is formed.

  Next, as shown in FIG. 5B, the metal layer 92 is formed into a predetermined shape. Specifically, a mask pattern (not shown) made of, for example, a resist is formed on the metal layer 92, and the metal layer 92 is patterned into a predetermined shape through this mask pattern (an area corresponding to the piezoelectric element 300). And a region corresponding to the communication portion 13 is removed). Then, as shown in FIG. 5C, by forming the base layer 91 into a predetermined shape, the lead electrode 90 and the discontinuous discontinuity between the lead electrode 90 in the vicinity of the peripheral edge of the communication portion 13 to be formed later. A metal layer 190 is formed. Specifically, as in the case of the base layer 91, a mask pattern (not shown) made of, for example, a resist is formed on the base layer 91, and the metal layer 92 is patterned into a predetermined shape via this mask pattern. (A region corresponding to the piezoelectric element 300 and a region corresponding to the communication portion 13 are removed). At this time, the end of the discontinuous metal layer 190 on the side where the communication part 13 of the metal layer 92 is formed is made shorter than the end of the base layer 91 on the side where the communication part 13 is formed. That is, the end portion of the discontinuous metal layer 190 on the side where the communicating portion 13 of the base layer 91 is formed protrudes beyond the end portion of the discontinuous metal layer 190 on the side where the communicating portion 13 of the metal layer 92 is formed. Like that.

  As described above, the discontinuous metal layer 190 can be formed simultaneously with the lead electrode 90. Since the discontinuous metal layer 190 is provided in the adhesion region (region where the adhesion layer 35 is formed) with the reservoir forming substrate wafer 130, there is no variation in height with the adhesion region on the lead electrode 90 side. In addition, it is possible to prevent problems caused by the flow of excess adhesive.

  Next, as illustrated in FIG. 6A, the reservoir forming substrate wafer 130 is bonded onto the flow path forming substrate wafer 110 via the adhesive layer 35. At this time, the adhesive layer 35 is joined to the upper surface of the end portion of the base layer 91 of the discontinuous metal layer 190 at the end portion on the side where the communication portion 13 is formed. As a result, the reservoir forming substrate wafer 130 and the flow path forming substrate wafer are firmly bonded. In addition, the adhesive layer 35 is formed so as to seal the end surface of the discontinuous metal layer 190 on the side of the communicating portion, so that even when the reservoir 31 and the communicating portion 13 are filled with ink during actual driving, the discontinuous metal layer 190 is discontinuous. The end surfaces of the base layer 91 and the metal layer 92 of the metal layer 190 do not come into contact with ink, and there is no possibility that the base layer 91 and the metal layer 92 are peeled off.

  The reservoir forming substrate wafer 130 is preliminarily formed with a reservoir portion 31, a piezoelectric element holding portion 32, and the like. The reservoir forming substrate wafer 130 is, for example, a silicon wafer having a thickness of about 400 μm, and the rigidity of the flow path forming substrate wafer 110 is significantly improved by bonding the reservoir forming substrate wafer 130. Become.

  Next, as shown in FIG. 6B, the flow path forming substrate wafer 110 is ground to a certain thickness, and further wet-etched with hydrofluoric acid to thereby reduce the flow path forming substrate wafer 110 to a predetermined thickness. Say it. For example, in this embodiment, the flow path forming substrate wafer 110 is processed to have a thickness of about 70 μm by grinding and wet etching. Next, as shown in FIG. 6C, a mask film 53 made of, for example, silicon nitride (SiN) is newly formed on the flow path forming substrate wafer 110 and patterned into a predetermined shape.

  Then, as shown in FIG. 7A, after the reservoir portion 31 of the reservoir forming substrate wafer 130 is sealed with, for example, an alkali-resistant sealing film 38, the flow path forming substrate is interposed via the mask film 53. The pressure wafer 12, the ink supply path 14, the communication path 15, the communication section 13, and the like are formed in the flow path forming substrate wafer 110 by anisotropic etching (wet etching) of the process wafer 110. At this time, although not shown, the entire surface of the reservoir forming substrate wafer 130 opposite to the flow path forming substrate wafer 110 is further covered with, for example, a heat-sealing film. Thus, since the reservoir portion 31 of the reservoir forming substrate wafer 130 is sealed with the sealing film 38, the etching wiring is provided on the surface of the reservoir forming substrate wafer 130 from the reservoir portion 31 side. And does not flow into the lead electrode 90. As a result, the etching solution does not adhere to the connection wiring and the lead electrode 90 provided on the surface of the reservoir forming substrate wafer 130, and the occurrence of defects such as disconnection can be prevented. At this time, since the end surface of the discontinuous metal layer 190 on the side of the communication portion is sealed with the adhesive layer 35, the end surface of the base layer 91 and the metal layer 92 of the discontinuous metal layer 190 is peeled off by wet etching. There is no fear.

  As shown in FIG. 7B, after peeling off the sealing film 38 and a heat-sealing film (not shown), the driving IC 120 is mounted on the connection wiring formed on the reservoir forming substrate wafer 130, and The driving IC 120 and the lead electrode 90 are connected by the connection wiring 121 (see FIG. 2). Thereafter, unnecessary portions of the outer peripheral edge portions of the flow path forming substrate wafer 110 and the reservoir forming substrate wafer 130 are removed by cutting, for example, by dicing. The nozzle plate 20 having the nozzle openings 21 is bonded to the surface of the flow path forming substrate wafer 110 opposite to the reservoir forming substrate wafer 130, and the compliance substrate 40 is attached to the reservoir forming substrate wafer 130. The ink jet recording head having the above-described structure is manufactured by bonding and dividing the flow path forming substrate wafer 110 and the like into a single chip size flow path forming substrate 10 as shown in FIG.

  As described above, in the liquid jet head according to the present embodiment, the end of the discontinuous metal layer 190 on the side of the communicating portion 13 of the base layer 91 protrudes from the end of the metal layer 92 side, and the communicating portion of the base layer 91. The upper surface of the side end portion is joined to the adhesive layer 35. As a result, the adhesion strength between the flow path forming substrate 10 and the reservoir forming substrate 30 is improved and firmly bonded.

  Furthermore, by covering the end surfaces and end portion upper surfaces of the elastic film 50 and the insulator film 55 with the base layer 91, the bonding area between the base layer 91 and the adhesive layer 35 is increased to increase the adhesion strength. Can do.

  Further, by forming the discontinuous metal layer 190 on the peripheral portion of the communication portion 13, it is possible to prevent variation in the joining height between the flow path forming substrate 10 and the reservoir forming substrate 30 and to prevent excess adhesive. Problems can be prevented.

  Furthermore, the end surface of the discontinuous metal layer 190 is covered with the adhesive layer 35. For this reason, even if the reservoir portion is filled with ink, the base layer 91 and the metal layer 92 of the discontinuous metal layer 190 do not come into contact with the ink, and there is no possibility that the base layer 91 and the metal layer 92 are separated.

  As a result, the liquid jet head of this embodiment has significantly improved durability and reliability.

(Other embodiments)
As mentioned above, although embodiment of this invention was described, the basic composition of this invention is not limited to what was mentioned above. For example, the end surface of the base layer 91 of the discontinuous metal layer 190 may not be covered with the adhesive layer 35.

  In this embodiment, the opening end faces of the elastic film 50 and the insulator film 55 are covered with the base layer 91 of the discontinuous metal layer 190. However, as shown in FIG. 9, the elastic film 50 and the insulator film The end face of 55 may not be covered with the discontinuous metal layer 190. Even in this case, the end portion of the discontinuous metal layer 190 on the side where the communicating portion 13 of the base layer 91 is formed is more than the end portion of the discontinuous metal layer 190 on the side where the communicating portion 13 of the metal layer 92 is formed. By projecting, there is no possibility that the interface between the base layer 91 and the metal layer 92 of the discontinuous metal layer 190 is peeled off, and the head can be improved in durability and reliability.

  Although the manufacturing method of the liquid jet head shown in FIG. 9 is not particularly limited, an example will be briefly described. After forming the piezoelectric element 300 by the same method as in the above embodiment, the base layer 91 and the metal layer 92 are formed over the entire surface of the flow path forming substrate wafer 110 without providing openings in the elastic film 50 and the insulator film 55. Form. Then, the metal layer 92 and the base layer 91 are patterned, and the end of the discontinuous metal layer 190 on the side where the communication portion 13 of the base layer 91 is formed is the communication portion 13 of the metal layer 92 of the discontinuous metal layer 190. It protrudes from the end part on the side where is formed. Thereafter, the elastic film 50 and the insulator film are formed when the pressure generation chamber 12, the ink supply path 14, the communication path 15, the communication section 13, and the like are formed on the flow path forming substrate wafer 110. 55 may be provided with an opening.

  The ink jet recording head described above constitutes a part of a recording head unit having an ink flow path communicating with an ink cartridge or the like, and is mounted on the ink jet recording apparatus. FIG. 10 is a schematic view showing an example of the ink jet recording apparatus.

  As shown in FIG. 10, the ink jet recording apparatus II includes recording head units 1 </ b> A and 1 </ b> B having an ink jet recording head I. The recording head units 1A and 1B are detachably provided with cartridges 2A and 2B constituting ink supply means. A carriage 3 on which the recording head units 1A and 1B are mounted is attached to a carriage shaft 5 attached to the apparatus main body 4. It is provided so as to be movable in the axial direction. The recording head units 1A and 1B, for example, are configured to eject a black ink composition and a color ink composition, respectively.

  The driving force of the driving motor 6 is transmitted to the carriage 3 via a plurality of gears and timing belt 7 (not shown), so that the carriage 3 on which the recording head units 1A and 1B are mounted is moved along the carriage shaft 5. The On the other hand, the apparatus body 4 is provided with a platen 8 along the carriage shaft 5, and a recording sheet S which is a recording medium such as paper fed by a paper feed roller (not shown) is wound around the platen 8. It is designed to be transported.

  Although the ink jet recording head I has been described as the liquid ejecting head, the present invention is widely applied to all liquid ejecting heads, and of course is applied to a method of manufacturing a liquid ejecting head that ejects liquid other than ink. can do. Applicable liquid ejecting heads include 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 FED (field emission displays). Examples thereof include an electrode material ejection head used for forming electrodes and a bioorganic matter ejection head used for biochip production.

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. 4 is a cross-sectional view illustrating the recording head manufacturing method according to the first embodiment. FIG. 4 is a cross-sectional view illustrating the recording head manufacturing method according to the first embodiment. FIG. 4 is a cross-sectional view illustrating the recording head manufacturing method according to the first embodiment. FIG. 4 is a cross-sectional view illustrating the recording head manufacturing method according to the first embodiment. FIG. 4 is a cross-sectional view illustrating the recording head manufacturing method according to the first embodiment. FIG. 3 is an enlarged cross-sectional view of the vicinity of a reservoir of the recording head according to the first embodiment. FIG. 6 is an enlarged cross-sectional view of the vicinity of a reservoir of a recording head according to another embodiment. 1 is a schematic diagram illustrating an example of an ink jet recording apparatus according to an embodiment.

Explanation of symbols

I ink jet recording head (liquid ejecting head), 10 flow path forming substrate, 12 pressure generating chamber, 13 communicating portion, 14 ink supply path, 15 communicating path, 20 nozzle plate, 21 nozzle opening, 30 reservoir forming substrate, 31 reservoir Part, 32 piezoelectric element holding part, 35 adhesive layer, 40 compliance substrate, 50 elastic film, 55 insulator film, 60 lower electrode film, 70 piezoelectric layer, 80 upper electrode film, 90 lead electrode, 91 underlayer, 92 metal Layer, 100 reservoir, 110 channel forming substrate wafer, 130 reservoir forming substrate wafer, 190 discontinuous metal layer, 300 piezoelectric element

Claims (6)

A flow path forming substrate in which a pressure generating chamber communicating with a nozzle opening for ejecting liquid and a communicating portion communicating with the pressure generating chamber are formed; a piezoelectric element provided on one side of the flow path forming substrate; A lead electrode made of a ground layer and a metal layer is joined to a surface on the piezoelectric element side of the flow path forming substrate via an adhesive layer, and communicates with the communicating portion to constitute a part of the reservoir. A reservoir forming substrate having a reservoir portion;
A discontinuous metal layer composed of the base layer and the metal layer discontinuous from the lead electrode is provided at the opening peripheral edge of the communication portion of the flow path forming substrate, and the discontinuous metal layer is formed of the base layer. The liquid ejecting head is characterized in that an end portion on the communication portion side protrudes from an end portion on the communication portion side of the metal layer, and an upper surface of the end portion on the communication portion side of the base layer is bonded to the adhesive layer.   The liquid ejecting head according to claim 1, wherein gold is used as a material of the metal layer.   3. The liquid jet head according to claim 1, wherein one material selected from the group consisting of nickel, chromium, and a nickel chromium compound is used as the material of the base layer.   4. The liquid ejecting head according to claim 1, wherein an end surface of the discontinuous metal layer on a communication portion side is sealed with the adhesive layer. 5.   A liquid ejecting apparatus comprising the liquid ejecting head according to claim 1. Forming a piezoelectric element on one side of a flow path forming substrate in which a pressure generating chamber communicating with a nozzle opening for ejecting liquid and a communicating portion communicating with the pressure generating chamber are formed;
Forming a metal layer on the surface of the flow path forming substrate on the piezoelectric element side via a base layer;
The underlayer and the metal layer in a region corresponding to the piezoelectric element and a region corresponding to the communication portion are removed to form a lead electrode drawn out from the piezoelectric element, and the bottom electrode is discontinuous with the lead electrode. Forming a discontinuous metal layer comprising a base layer and the metal layer;
Bonding a reservoir forming substrate having a reservoir portion that communicates with the communication portion and forms a part of the reservoir to the surface on the piezoelectric element side of the flow path forming substrate via an adhesive layer;
When the discontinuous metal layer is formed, the discontinuous metal layer has an end on the side where the communicating portion of the base layer is formed protrudes beyond an end on the side where the communicating portion of the metal layer is formed. Then, when the flow path forming substrate and the reservoir forming substrate are bonded, the upper surface of the end portion on the side where the communicating portion of the base layer is formed and the adhesive layer are bonded to each other. Manufacturing method of ejection head.

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