JP4218309B2 - Liquid ejecting head and liquid ejecting apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid ejecting head that ejects a liquid to be ejected, a method for manufacturing the same, and a liquid ejecting apparatus, and in particular, pressurizes ink supplied to a pressure generating chamber that communicates with a nozzle opening that ejects ink droplets using a piezoelectric element. The present invention relates to an ink jet recording head that discharges ink droplets from a nozzle opening, a manufacturing method thereof, and an ink jet recording apparatus.
[0002]
[Prior art]
A part of the pressure generation chamber communicating with the nozzle opening for discharging ink droplets is constituted by a vibration plate, and the vibration plate is deformed by a piezoelectric element to pressurize the ink in the pressure generation chamber to discharge ink droplets from the nozzle opening. Two types of ink jet recording heads have been put into practical use: those using a longitudinal vibration mode piezoelectric actuator that extends and contracts in the axial direction of the piezoelectric element, and those using a flexural vibration mode piezoelectric actuator.
[0003]
As an example of using an actuator in a flexural vibration mode, for example, a uniform piezoelectric material layer is formed by a film forming technique over the entire surface of the diaphragm, and this piezoelectric material layer is formed into a pressure generating chamber by a lithography method. A device in which a piezoelectric element is formed so as to be cut into a corresponding shape and independent for each pressure generating chamber is known.
[0004]
The piezoelectric element used for the actuator in the flexural vibration mode includes, for example, a lower electrode that is a common electrode, a PZT film (piezoelectric layer) formed on the lower electrode, and an individual electrode formed on the PZT film. It is comprised with the upper electrode which is. Further, an interlayer insulating film is formed on the upper electrode to insulate the lower electrode from the upper electrode, and a wiring electrically connected to the upper electrode through a contact hole opened in the interlayer insulating film. The structure is provided (see, for example, Patent Document 1).
[0005]
[Patent Document 1]
Japanese Patent Laid-Open No. 10-211701 (pages 9-10 and 13-20)
[Patent Document 2]
Japanese Patent Laid-Open No. 2002-11877 (page 4-5, FIG. 1-9)
[0006]
[Problems to be solved by the invention]
In such a conventional ink jet recording head, since the lower electrode is provided in common to a plurality of piezoelectric elements, a voltage drop occurs when a large number of ink droplets are ejected at the same time by simultaneously driving a large number of piezoelectric elements. Occurs, the amount of displacement of the piezoelectric element becomes unstable, and there is a problem that the ink ejection characteristics deteriorate. In addition, the electrode of the piezoelectric element formed of a thin film has a relatively high resistance value because of its thin film thickness, and this problem is particularly likely to occur. In addition, such a problem can be solved by increasing the thickness of the lower electrode. However, since the lower electrode substantially constitutes a part of the diaphragm, the diaphragm is driven by driving the piezoelectric element. There is a problem that the amount of displacement decreases. Although such a problem can be solved by increasing the area of the common electrode, there is a problem that the head becomes large.
[0007]
Furthermore, in order to solve such problems, a plurality of lower electrode films (lower electrodes) are classified into several groups, and each common terminal is provided corresponding to each group, so that the voltage drop is suppressed and the actuator Some have achieved uniform characteristics of the piezoelectric element (see, for example, Patent Document 2).
[0008]
With such a structure, the occurrence of a voltage drop can certainly be suppressed, but the number of terminals is greatly increased and the wiring structure becomes complicated, so that the manufacturing process becomes complicated and the piezoelectric element increases. There is a problem that it is difficult to adopt when arranged in the density.
[0009]
Such a problem exists not only in the manufacturing method of the ink jet recording head that discharges ink but also in the manufacturing method of other liquid jet heads that discharge other than ink.
[0010]
In view of such circumstances, the present invention provides a liquid ejecting head that can satisfactorily maintain ink ejection characteristics, obtain stable ink ejection characteristics, and can arrange piezoelectric elements at high density, and a method for manufacturing the same, It is an object to provide a liquid ejecting apparatus.
[0011]
[Means for Solving the Problems]
A first aspect of the present invention that solves the above problems includes a flow path forming substrate in which a pressure generating chamber communicating with a nozzle opening for ejecting liquid is formed, and a diaphragm in a region on one side of the flow path forming substrate. A liquid ejecting head comprising a lower electrode, a piezoelectric layer, and a piezoelectric element comprising an upper electrode, and the lower electrode is patterned in the vicinity of the longitudinal end of the pressure generating chamber to generate each pressure. A piezoelectric active portion that is substantially a driving portion of the piezoelectric element is formed in a region facing the chamber, and a lead-out wiring that is led out from the upper electrode that is an individual electrode of the piezoelectric element to a terminal portion; Bypass wiring extending from the lower electrode, which is a common electrode of the piezoelectric element, to the terminal portion, in which a part of each lead-out wiring is continuously covered by an insulating film provided without covering the piezoelectric active portion Less Some Ku and also has a liquid-jet head, characterized in that it is extended on the insulating film.
[0012]
In the first aspect, since the resistance value of the lower electrode is substantially reduced by the bypass wiring, the voltage drop when driving the piezoelectric element is prevented, and the ink ejection characteristics are always kept good.
[0013]
According to a second aspect of the present invention, in the first aspect, the lead-out wiring includes a lead electrode having one end connected to the upper electrode, and a connection wiring that connects the lead electrode and the terminal portion. The liquid ejecting head is configured, wherein the insulating film is provided on the connection wiring.
[0014]
In the second aspect, since the insulating film is provided on the connection wiring constituting the extraction wiring, it is easy to manufacture the extraction wiring, the bypass wiring, and the like.
[0015]
According to a third aspect of the present invention, in the liquid jet head according to the second aspect, the connection wiring is made of the same film as the lower electrode.
[0016]
In the third aspect, the lower electrode and the connection wiring can be formed in the same process, and the manufacturing process is simplified.
[0017]
According to a fourth aspect of the present invention, in the liquid jet head according to the second or third aspect, the bypass wiring is made of the same film as the lead electrode.
[0018]
In the fourth aspect, the bypass wiring and the lead electrode can be formed in the same process, and the manufacturing process is simplified.
[0019]
According to a fifth aspect of the present invention, in any one of the first to fourth aspects, a sealing substrate having a piezoelectric element holding portion that is a space for sealing the piezoelectric element on the piezoelectric element side of the flow path forming substrate. In the liquid ejecting head, at least a part of the insulating film is sealed in the piezoelectric element holding portion together with the piezoelectric element.
[0020]
In the fifth aspect, since the insulating film is sealed in the piezoelectric element holding portion, by using a hygroscopic material as the insulating film, the inside of the piezoelectric element holding portion can be always kept dry, Destruction of the piezoelectric element due to moisture is prevented.
[0021]
According to a sixth aspect of the present invention, in the liquid jet head according to any one of the first to fifth aspects, the insulating film is formed of an organic material.
[0022]
In the sixth aspect, the insulating film can be formed relatively easily. In addition, when the insulating film is sealed in the piezoelectric element holding portion, the moisture in the piezoelectric element holding portion is absorbed by the insulating film, and the piezoelectric element is prevented from being damaged due to moisture.
[0023]
According to a seventh aspect of the present invention, in the liquid jet head according to the sixth aspect, the organic material is polyimide.
[0024]
In the seventh aspect, the insulating film can be more easily formed by using a predetermined material. In addition, when the insulating film is sealed in the piezoelectric element holding portion, moisture in the piezoelectric element holding portion is surely absorbed by the insulating film, and destruction due to moisture of the piezoelectric element is prevented.
[0025]
An eighth aspect of the present invention is a liquid ejecting apparatus including the liquid ejecting head according to any one of the first to seventh aspects.
[0026]
In the eighth aspect, it is possible to realize a liquid ejecting apparatus with improved ejection characteristics and improved reliability.
[0027]
According to a ninth aspect of the present invention, a flow path forming substrate in which a pressure generating chamber communicating with a nozzle opening for ejecting liquid is formed, and a region on one side of the flow path forming substrate is provided via a diaphragm. In a method for manufacturing a liquid jet head comprising a lower electrode, a piezoelectric layer, and a piezoelectric element comprising an upper electrode, a lower electrode forming film is formed and patterned to place the lower electrode in a region corresponding to the pressure generating chamber. Forming a connecting wire that forms a part of the lead-out wire led out from the upper electrode, and forming the piezoelectric material forming film and the upper electrode independently on the pressure generation chamber for each pressure generation chamber. Forming and patterning a forming film to form a piezoelectric element including the lower electrode, the piezoelectric layer, and the upper electrode; and connecting the piezoelectric element without covering a piezoelectric active part that is a substantial driving unit of the piezoelectric element. Both ends on the wiring A step of forming an insulating film so as to continuously cover a region excluding the side, a lead electrode that connects the upper electrode and the connection wiring and connects the connection wiring and the terminal portion, and at least a part of the lead electrode The method of manufacturing a liquid ejecting head includes a step of forming a bypass wiring extending on an insulating film and connecting the lower electrode and the terminal portion with the same film.
[0028]
In the ninth aspect, each layer can be formed without complicating the manufacturing process.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
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, and FIG. 2 is a schematic plan view of FIG. 1 and a sectional view taken along line AA ′. 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 has a thickness of 1 to 2 μm made of silicon dioxide previously formed by thermal oxidation on both surfaces. A mask film 55 used as a mask when forming the elastic film 50 and a pressure generation chamber described later is provided. The flow path forming substrate 10 is provided with pressure generating chambers 12 partitioned by a plurality of partition walls 11 in parallel in the width direction by performing anisotropic etching from the other direction side. A communication portion 13 constituting a part of the reservoir 100 serving as a common ink chamber of the generation chamber 12 is formed, and the communication portion 13 communicates with one end portion in the longitudinal direction of each pressure generation chamber 12 via an ink supply path 14. Has been.
[0030]
Here, the anisotropic etching is performed by utilizing the difference in etching rate of the silicon single crystal substrate. For example, in this embodiment, when a silicon single crystal substrate is immersed in an alkaline solution such as KOH, the first (111) plane perpendicular to the (110) plane is gradually eroded, and the first (111) plane. And a second (111) plane that forms an angle of about 70 degrees with the (110) plane and an angle of about 35 degrees appears, and the (111) plane is compared with the etching rate of the (110) plane. This is performed using the property that the etching rate is about 1/180. By this anisotropic etching, precision processing can be performed based on the parallelogram depth processing formed by two first (111) surfaces and two oblique second (111) surfaces. The pressure generating chambers 12 can be arranged with high density. In the present embodiment, the long side of each pressure generating chamber 12 is formed by the first (111) plane and the short side is formed by the second (111) plane. The pressure generation chamber 12 is formed by etching until it substantially passes through the flow path forming substrate 10 and reaches the elastic film 50. Here, the amount of the elastic film 50 that is affected by the alkaline solution for etching the silicon single crystal substrate is extremely small. 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 kept constant. is doing.
[0031]
The thickness of the flow path forming substrate 10 may be selected as the optimum thickness according to the arrangement density of the pressure generating chambers 12, and the arrangement density of the pressure generating chambers 12 is, for example, 180 per inch ( If it is about 180 dpi), the thickness of the flow path forming substrate 10 may be about 220 μm. However, for example, when arranged at a relatively high density of 200 dpi or more, the thickness of the flow path forming substrate 10 is It is preferable to make it relatively thin as 100 μm or less. This is because the arrangement density can be increased while maintaining the rigidity of the partition wall 11 between the adjacent pressure generation chambers 12.
[0032]
Further, the nozzle plate 20 in which the nozzle opening 21 communicating with the side opposite to the ink supply path 14 of each pressure generating chamber 12 is formed on the mask film 55 on the opening surface side of the flow path forming substrate 10 is an adhesive. It is fixed via a heat welding film or the like. The nozzle plate 20 has a thickness of, for example, 0.1 to 1 mm and a linear expansion coefficient of 300 ° C. or less, for example, 2.5 to 4.5 [× 10 ^-6 / ° C] glass ceramics or non-rust steel. The nozzle plate 20 entirely covers one surface of the flow path forming substrate 10 on one surface, and also serves as a reinforcing plate that protects the silicon single crystal substrate from impact and external force. 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. In this case, since the deformation by heat of the flow path forming substrate 10 and the nozzle plate 20 is substantially the same, it can be easily joined using a thermosetting adhesive or the like. Here, the size of the pressure generation chamber 12 that applies ink droplet discharge pressure to the ink and the size of the nozzle opening 21 that discharges the ink droplet are optimized according to the amount of ink droplet to be discharged, the discharge speed, and the discharge frequency. The For example, when recording 360 ink droplets per inch, the nozzle opening 21 needs to be accurately formed with a diameter of several tens of μm.
[0033]
On the other hand, on the elastic film 50 opposite to the opening surface of the flow path forming substrate 10, the lower electrode film 60 with a thickness of, for example, about 0.2 μm and a thickness of, for example, about 0.5 to 5 μm. The piezoelectric layer 70 and the upper electrode film 80 having a thickness of, for example, about 0.1 μm are laminated by a process described later to constitute the piezoelectric element 300. Here, the piezoelectric element 300 refers to a portion including the lower electrode film 60, the piezoelectric layer 70, and the upper electrode film 80. In general, one electrode of the piezoelectric element 300 is used as a common electrode, and the other electrode and the piezoelectric layer 70 are patterned for each pressure generating chamber 12. In addition, here, a portion that is configured by any one of the patterned electrodes and the piezoelectric layer 70 and in which piezoelectric distortion is generated by applying a voltage to both electrodes is referred to as a piezoelectric active portion 320. In this embodiment, the lower electrode film 60 is a common electrode of the piezoelectric element 300, and the upper electrode film 80 is an individual electrode of the piezoelectric element 300. However, there is no problem even if this is reversed for the convenience of the drive circuit and wiring. In either case, a piezoelectric active part is formed for each pressure generating chamber. Further, here, the piezoelectric element 300 and the vibration plate that is displaced by driving the piezoelectric element 300 are collectively referred to as a piezoelectric actuator. In the example described above, the elastic film 50 and the lower electrode film 60 act as a diaphragm.
[0034]
Here, in the present embodiment, the lower electrode film 60 that is a common electrode of the piezoelectric element 300 is removed by removing the regions outside both ends in the longitudinal direction of the pressure generating chamber 12 by patterning, and only in the region corresponding to the pressure generating chamber 12. Is formed. That is, the lower electrode film 60 has a width narrower than the length of the pressure generation chamber 12 and extends along the direction in which the pressure generation chambers 12 are arranged.
[0035]
On the other hand, each upper electrode film 80, which is an individual electrode of the piezoelectric element 300, is provided in the vicinity of the end of the flow path forming substrate 10 from a region facing the lower electrode film 60, that is, a region facing the piezoelectric body active portion 320. A lead wiring 110 that is led out to the terminal portion 120 is connected. The terminal portion 120 is a portion to which drive wiring (not shown) connected to a drive IC or the like is connected. In the present embodiment, the vicinity of the end portion of the lead-out wiring 110 is the terminal portion 120. Specifically, the lead-out wiring 110 includes a first lead electrode 111 extending from the upper electrode film 80 to the outside of the pressure generation chamber 12, a second lead electrode 112 constituting the terminal portion 120, and the first lead electrode 111. The first lead electrode 111 and the second lead electrode 112 (terminal portion 120) are connected to each other and formed with a connection wiring 113. Here, the connection wiring 113 is made of the same film as the lower electrode film 60, for example, platinum (Pt), and the first and second lead electrodes 111, 112 are made of a material having relatively high conductivity, for example, gold. (Au). In the present embodiment, a protective film 114 made of the same film as the first and second lead electrodes 111 and 112 is provided at the end of the piezoelectric element 300 opposite to the lead-out wiring 110, and the piezoelectric element 300 is provided. This prevents the vicinity of the end portion from being damaged by driving. Of course, the protective film 114 may not be provided.
[0036]
A part of the lead wiring 110 is covered with an insulating film 130, and a bypass wiring 140 that connects the lower electrode film 60 and the terminal portion 120 is provided on the insulating film 130. The insulating film 130 is provided so as to cover a part of the lead wiring 110, but is formed without covering a region facing the piezoelectric active portion 320. In the present embodiment, the connection wiring 113 of each lead-out wiring 110, specifically, the portion excluding the region where the first and second lead electrodes in the vicinity of both ends of the connection wiring 113 are connected is continuously formed by the insulating film 130. Covered. As will be described in detail later, the insulating film 130 is preferably formed of an organic material. In this embodiment, the insulating film 130 is formed of polyimide.
[0037]
Further, the bypass wiring 140 is formed on the insulating film 130 with a width slightly narrower than the width of the insulating film 130, and the vicinity of the end serves as the terminal portion 120. Further, the bypass wiring 140 has a connection portion 141 extending to the region facing the partition wall 11 along the lead-out wiring 110, and is connected to the lower electrode film 60 through the connection portion 141. The connecting portion 141 may be provided in at least one place, but is preferably provided in a plurality of places. For example, in this embodiment, the connecting portion 141 is provided for every three piezoelectric elements 300. (See FIG. 1). In addition, the space | interval of the connection part 141 is not specifically limited, For example, you may make it provide the connection part 141 between each piezoelectric element 300, respectively. In addition, the bypass wiring 140 is preferably formed of a material having higher conductivity than the lower electrode film 60. In the present embodiment, the bypass wiring 140 is formed of the same film as the first and second lead electrodes 111 and 112. Has been.
[0038]
Thus, the bypass wiring 140 connected to the lower electrode 60 that is the common electrode of the piezoelectric element 300 is provided on the lead-out wiring 110 that is drawn from the upper electrode film 80 that is the individual electrode of the piezoelectric element 300 via the insulating film 130. As a result, the resistance value of the lower electrode film 60 can be substantially reduced without reducing the displacement characteristics of the diaphragm. Therefore, even if a large number of piezoelectric elements are driven simultaneously, a voltage drop does not occur, and always good and stable ink ejection characteristics can be obtained. In particular, by using a material having higher conductivity than the material of the lower electrode film 60 for the bypass wiring 140, the resistance value of the lower electrode film 60 can be reduced relatively easily, and the head can be downsized. You can also plan.
[0039]
In addition, a sealing substrate 30 having a piezoelectric element holding portion 31 capable of sealing the space is bonded to the flow path forming substrate 10 in a state where a space that does not hinder the movement of the piezoelectric element 300 is secured. The element 300 is sealed in the piezoelectric element holding portion 31. In this embodiment, the insulating film 130 provided on the connection wiring 113 of the lead-out wiring 110 is also sealed in the piezoelectric element holding portion 31. The insulating film 130 is made of an organic material, in this embodiment, polyimide. For this reason, since the insulating film 130 absorbs moisture (humidity) in the piezoelectric element holding portion 31 and the inside of the piezoelectric element holding portion 31 is always kept in a dry state, the piezoelectric element 300 is prevented from being damaged due to moisture. be able to. Furthermore, since the insulating film 130 is formed without covering the piezoelectric active part 320, even if the insulating film 130 absorbs moisture, the piezoelectric active part 320 is not destroyed thereby.
[0040]
In addition, the sealing substrate 30 is provided with a reservoir portion 32 that constitutes at least a part of the reservoir 100. The reservoir portion 32 is formed through the sealing substrate 30 in the thickness direction and across the width direction of the pressure generating chamber 12, and the flow path forming substrate 10 is formed through a communication hole provided in the elastic film 50. The reservoir 100 is connected to the communication portion 13 and serves as an ink chamber common to the pressure generation chambers 12. As such a sealing 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, a ceramic material, etc., and in this embodiment, the same as the flow path forming substrate 10. It was formed using a silicon single crystal substrate of the material.
[0041]
Furthermore, a compliance substrate 40 including a sealing film 41 and a fixing plate 42 is bonded onto the sealing 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.
[0042]
In such an ink jet recording head of this 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 driven according to a drive signal from a drive IC (not shown). By applying a driving voltage between each of the lower electrode film 60 and the upper electrode film 80 corresponding to the pressure generating chamber 12, the elastic film 50, the lower electrode film 60, and the piezoelectric layer 70 are bent and deformed. The pressure in the pressure generating chamber 12 increases and ink droplets are ejected from the nozzle openings 21.
[0043]
3 and 4 are longitudinal sectional views of the pressure generating chamber 12, and a method for manufacturing the ink jet recording head of this embodiment will be described below with reference to FIGS. First, as shown in FIG. 3A, a silicon dioxide film that forms an elastic film 50 and a mask film 55 by thermally oxidizing a silicon single crystal substrate wafer to be a flow path forming substrate 10 in a diffusion furnace at about 1100 ° C. 51 is formed on the entire surface. Next, as shown in FIG. 3B, for example, after forming a lower electrode forming film 65 to be the lower electrode film 60 made of platinum or the like on the silicon dioxide film 51 to be the elastic film 50, the lower electrode forming film 65 is formed. By patterning, the lower electrode film 60 is formed in a region corresponding to the pressure generation chamber 12, and the connection wiring 113 constituting the extraction wiring 110 is formed outside the pressure generation chamber 12 in the longitudinal direction. Thus, if the connection wiring 113 is formed of the same film (lower electrode formation film 65) as the lower electrode film 60, the connection wiring 113 can be easily formed without complicating the manufacturing process.
Next, as shown in FIG. 3C, the piezoelectric body forming film 75 made of, for example, lead zirconate titanate (PZT), and many metals such as aluminum, gold, nickel, platinum, or the like An upper electrode forming film 85 made of an oxide or the like is sequentially laminated, and these are simultaneously patterned to form a piezoelectric element 300 made up of the lower electrode film 60, the piezoelectric layer 70, and the upper electrode film 80.
[0044]
Next, as shown in FIG. 3D, for example, an insulating film forming layer 135 made of an organic material such as polyimide is formed on the entire surface of the flow path forming substrate 10 and then patterned to correspond to the connection wiring 113. An insulating film 130 is formed in the region. Next, as shown in FIG. 4A, the first and second lead electrodes 111 and 112, the protective film 114, and the bypass wiring 140 constituting the lead wiring 110 are formed simultaneously. That is, for example, a metal film 115 made of gold (Au) or the like is formed over the entire surface of the flow path forming substrate 10, and the metal film 115 is patterned so that the first and second elements are provided for each piezoelectric element 300. The lead electrodes 111 and 112 are formed, and a bypass wiring 140 extending in a region facing the insulating film 130 is formed. Further, a protective film 114 is formed on the end of the piezoelectric element 300 opposite to the first lead electrode 111. Thus, by forming the bypass wiring 140 with the same film (metal film 115) as the first and second lead electrodes 111 and 112, the bypass wiring 140 can be easily formed without complicating the manufacturing process. Can do.
[0045]
The above is the film forming process. After film formation in this way, anisotropic etching of the silicon single crystal substrate (flow path forming substrate 10) with the alkali solution described above is performed to form the pressure generating chamber 12, the communication portion 13, and the ink supply path 14. To do. Specifically, first, as shown in FIG. 4B, the sealing substrate 30 on which the piezoelectric element holding portion 31, the reservoir portion 32, and the like are formed in advance is bonded to the flow path forming substrate 10 on the piezoelectric element 300 side. To do. Next, as shown in FIG. 4C, the silicon dioxide film 51 formed on the surface of the flow path forming substrate 10 opposite to the bonding surface with the sealing substrate 30 is patterned into a predetermined shape and masked. The pressure generation chamber 12, the communication portion 13, the ink supply path 14, and the like are formed in the flow path forming substrate 10 by forming the film 55 and performing the anisotropic etching with the alkali solution described above through the mask film 55. Note that the anisotropic etching is performed in a state where the surface of the sealing substrate 30 is sealed.
[0046]
After that, the nozzle plate 20 having the nozzle openings 21 formed on the surface of the flow path forming substrate 10 opposite to the sealing substrate 30 is bonded, and the compliance substrate 40 is bonded to the sealing substrate 30. By dividing into each chip size, the ink jet recording head of this embodiment as shown in FIG. 1 is obtained.
[0047]
(Other embodiments)
As mentioned above, although embodiment of this invention was described, of course, this invention is not limited to the above-mentioned embodiment. For example, in the above-described embodiment, the bypass wiring 140 is formed of the same film as the first and second lead electrodes 111 and 112. Of course, the bypass wiring 140 includes the first and second lead electrodes. 111 and 112 may be formed separately. In any case, the bypass wiring 140 is desirably made of a material having higher conductivity than the lower electrode film 60. As a result, the resistance value of the lower electrode film 60 can be substantially reduced without increasing the thickness of the bypass wiring 140 so much. Further, when the bypass wiring 140 is formed separately from the first and second lead electrodes 111 and 112, after forming the continuous lead wiring from the upper electrode film 80 to the terminal portion 120, the insulating film 130 and the bypass wiring 140 are formed. You may make it provide. Furthermore, in the above-described embodiment, the connection wiring 113 is formed of the same material as the lower electrode film 60. However, the connection wiring 113 may be provided separately from the lower electrode film 60.
[0048]
Such an ink jet recording head constitutes a part of a recording head unit including an ink flow path communicating with an ink cartridge or the like, and is mounted on the ink jet recording apparatus. FIG. 5 is a schematic view showing an example of the ink jet recording apparatus. As shown in FIG. 5, in the recording head units 1A and 1B having the ink jet recording head, cartridges 2A and 2B constituting ink supply means are detachably provided, and a carriage 3 on which the recording head units 1A and 1B are mounted. Is provided on a carriage shaft 5 attached to the apparatus body 4 so as to be movable in the axial direction. The recording head units 1A and 1B, for example, are configured to eject a black ink composition and a color ink composition, respectively. The driving force of the driving motor 6 is transmitted to the carriage 3 via a plurality of gears and timing belt 7 (not shown), so that the carriage 3 on which the recording head units 1A and 1B are mounted is moved along the carriage shaft 5. The On the other hand, the apparatus body 4 is provided with a platen 8 along the carriage shaft 5, and a recording sheet S which is a recording medium such as paper fed by a paper feed roller (not shown) is conveyed onto the platen 8. It is like that.
[0049]
In addition, the ink jet recording head and the ink jet recording apparatus that discharge ink as the liquid ejecting head have been described as examples. However, the present invention is widely intended for the liquid ejecting head and the liquid ejecting apparatus in general. Examples of the liquid ejecting head include a recording head used in an image recording apparatus such as a printer, a color material ejecting head used for manufacturing a color filter such as a liquid crystal display, an organic EL display, and an electrode formation such as an FED (surface emitting display). Electrode material ejecting heads used in manufacturing, bioorganic matter ejecting heads used in biochip production, and the like.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view of a recording head according to a 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 a cross-sectional view showing a manufacturing process of the recording head according to the first embodiment.
4 is a cross-sectional view illustrating a manufacturing process of a recording head according to Embodiment 1. FIG.
FIG. 5 is a schematic diagram of a recording apparatus according to an embodiment.
[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 Sealing board, 31 Piezoelectric element holding part, 32 Reservoir part, 40 Compliance board, 50 Elastic film , 60 lower electrode film, 70 piezoelectric layer, 80 upper electrode film, 100 reservoir, 110 lead-out wiring, 111 first lead electrode, 112 second lead electrode, 113 connection wiring, 120 terminal portion, 130 insulating film, 140 Bypass wiring, 141 connection, 300 piezoelectric element

Claims (8)

A flow path forming substrate in which a plurality of pressure generation chambers communicating with nozzle openings for injecting liquid are formed; a common electrode provided on one side of the flow path forming substrate via a diaphragm; a piezoelectric layer; and anda piezoelectric element composed of the individual electrodes, the common electrode and the voltage liquid jet head piezoelectric active portion piezoelectric distortion is formed by the application of to the individual electrodes in a region facing the pressure generating chamber Leave
An insulating film having a lead- out line led out from the individual electrode to the terminal part , and a bypass line electrically connected to the common electrode through a connection part, and provided without covering the piezoelectric active part more said portion of the extraction wiring is covered, the liquid ejecting head at least a portion of the bypass wire is characterized in that it is extended on the insulating film. The liquid ejecting head according to claim 1, wherein a sealing substrate having a piezoelectric element holding portion which is a space for sealing the piezoelectric element is bonded to the piezoelectric element side of the flow path forming substrate, and is formed of an organic material. At least a part of the insulating film is sealed in the piezoelectric element holding portion together with the piezoelectric element. The liquid ejecting head according to claim 2 , wherein the organic material is polyimide. Oite the liquid jet head according to any one of claims 1 to 3, wherein the lead-out wiring, connected to the lead electrode whose one end is connected to the individual electrodes, between the lead electrode and the terminal portion A liquid ejecting head, wherein the insulating film is provided on the connection wiring. The liquid ejecting head according to claim 1 , wherein the bypass wiring has higher conductivity than the common electrode . The liquid ejecting head according to claim 1 , wherein the connecting portion is provided at a plurality of locations . The liquid ejecting head according to claim 1, wherein the connection portion is provided between the piezoelectric elements . A liquid ejecting apparatus comprising the liquid ejecting head according to any one of claims 1 to 7.

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