JP2000135790A - Actuator device, ink jet recording head, and ink jet recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provided an actuator whose structure is simplified and size is reduced, an ink jet recording head, and an ink jet recording device. SOLUTION: In the actuator device including a passage formation substrate on which pressure generation chambers 12 are separately formed and which has a piezoelectric element on one of the surfaces of the pressure generation chamber 12 via a vibrating plate, a joined member 120 joined to the piezoelectric-element side of the passage formation substrate 10 is provided. In the joined member 120, a mounting part to which an external wiring is connected is provided in an area opposite to the piezoelectric element, also a wiring for driving whose one end is connected to the mounting part of the joined member 120 and other end is connected to the piezoelectric element is provided. Thus, the purpose is easily realized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an actuator in which a driving IC is mounted on a flow path forming substrate having a piezoelectric element, an ink jet recording head in which a nozzle forming member is laminated on the actuator, and an ink jet recording apparatus.

[0002]

2. Description of the Related Art A part of a pressure generating chamber communicating with a nozzle opening for discharging ink droplets is constituted by a vibrating plate, and the vibrating plate is deformed by a piezoelectric element to pressurize the ink in the pressure generating chamber to pass through the nozzle opening. Two types of ink jet recording heads that eject ink droplets have been commercialized, one using a longitudinal vibration mode piezoelectric actuator that expands and contracts in the axial direction of the piezoelectric element, and the other using a flexural vibration mode piezoelectric actuator. ing.

In the former method, the volume of the pressure generating chamber can be changed by bringing the end face of the piezoelectric element into contact with the diaphragm, so that a head suitable for high-density printing can be manufactured. There is a problem in that a difficult process of cutting into a comb shape in accordance with the arrangement pitch of the openings and an operation of positioning and fixing the cut piezoelectric element in the pressure generating chamber are required, and the manufacturing process is complicated.

On the other hand, in the latter, a piezoelectric element can be formed on a diaphragm by a relatively simple process of sticking a green sheet of a piezoelectric material according to the shape of a pressure generating chamber and firing the green sheet. In addition, there is a problem that a certain area is required due to the use of flexural vibration, and that high-density arrangement is difficult.

On the other hand, in order to solve the latter disadvantage of the recording head, a uniform piezoelectric material layer is formed by a film forming technique over the entire surface of the diaphragm as disclosed in Japanese Patent Application Laid-Open No. 5-286131. A proposal has been made in which the piezoelectric material layer is cut into a shape corresponding to the pressure generating chambers by a lithography method, and a piezoelectric element is formed so as to be independent for each pressure generating chamber.

This eliminates the need for attaching the piezoelectric element to the vibration plate, which not only allows the piezoelectric element to be manufactured by a precise and simple method such as lithography, but also reduces the thickness of the piezoelectric element. There is an advantage that it can be made thin and can be driven at high speed.

Further, in this case, for example, a silicon single crystal substrate is used as a substrate, and flow paths such as a pressure generation chamber and a reservoir are formed by anisotropic etching to reduce the opening area of the pressure generation chamber as much as possible. Thus, the recording density can be improved.

[0008]

In any case, the above-described ink jet recording head requires a semiconductor integrated circuit (IC) for driving the piezoelectric element, and is mounted near the ink jet recording head. . That is, in the related art, a method has been adopted in which an IC is arranged near a piezoelectric element and wiring is performed by wire bonding or the like.

However, in particular, as the recording density is improved, the space for mounting ICs and the like and the space for wiring between each piezoelectric element and the ICs and the like are problems in reducing the size of the recording head. In addition, such a problem exists in any device equipped with an actuator having a similar piezoelectric element.

In view of such circumstances, an object of the present invention is to provide an actuator device, an ink jet recording head, and an ink jet recording device whose structures are simplified and miniaturized.

[0011]

According to a first aspect of the present invention for solving the above-mentioned problems, a pressure generating chamber is defined and a piezoelectric element is provided on one side of the pressure generating chamber via a diaphragm. In the actuator device including the flow path forming substrate, a bonding member that is bonded to the piezoelectric element side of the flow path forming substrate, wherein a mounting portion to which external wiring is connected has the mounting portion connected to the piezoelectric element. Is provided in a region on the opposite side, and one end is connected to the mounting portion of the joining member, and the other end is provided with a driving wire connected to the piezoelectric element. is there.

According to the first aspect, since the mounting portion is provided on the joining member joined to the piezoelectric element side of the flow path forming substrate, the connection structure with the external wiring can be saved.
It is possible to realize miniaturization and high density.

According to a second aspect of the present invention, in the first aspect, a contact portion for connecting to a drive electrode of the piezoelectric element is provided on a surface of the flow path forming substrate on the joining member side, On the surface of the joining member on the side of the flow path forming substrate, a connecting portion at the other end of the driving wiring is arranged corresponding to the contact portion, and the contact portion and the connecting portion are pressure-bonded. The actuator device is characterized in that:

In the second aspect, by joining the flow path forming substrate and the joining member, wiring connection with each piezoelectric element is performed, and assembly is facilitated.

A third aspect of the present invention is the actuator device according to the first or second aspect, wherein the driving wiring is provided in the joining member.

In the third aspect, it is not necessary to secure a space for providing the drive wiring, and it is possible to surely realize the miniaturization and the high density.

According to a fourth aspect of the present invention, in any one of the first to third aspects, the connecting member includes a communication portion which penetrates the connecting member and communicates with the outside in a region corresponding to the piezoelectric element. A hole is provided, and the drive wiring is provided through the communication hole.

In the fourth aspect, the drive wiring is easily connected to the external wiring via the continuous pain hole.

According to a fifth aspect of the present invention, in the actuator device according to the fourth aspect, the driving wiring is formed by wire bonding.

According to the fifth aspect, the driving wiring can be easily formed.

A sixth aspect of the present invention is the actuator device according to the fourth aspect, wherein the drive wiring is formed of a thin film.

In the sixth aspect, the driving wiring can be easily connected.

According to a seventh aspect of the present invention, in any one of the first to sixth aspects, a driving circuit for driving the piezoelectric element is mounted in a region of the joining member opposite to the piezoelectric element. The drive circuit is connected between the drive wiring and the mounting section.

According to the seventh aspect, the actuator device can be formed only by joining the flow path forming substrate and the joining member, and the space can be saved.

An eighth aspect of the present invention is the actuator device according to the seventh aspect, wherein the drive circuit is formed directly on the joining member.

In the eighth aspect, there is no need to separately mount a driving integrated circuit, and the manufacturing cost can be reduced.

A ninth aspect of the present invention is the actuator device according to the seventh aspect, wherein the drive circuit is a semiconductor integrated circuit.

In the ninth aspect, the drive circuit can be easily mounted on the joining member, and the space can be surely saved.

In a tenth aspect of the present invention, the first to ninth aspects
A nozzle forming member having a nozzle opening communicating with the pressure generating chamber is joined to the other surface side of the flow path forming substrate of the actuator device according to any one of the above aspects to form a head chip. In the ink jet recording head.

In the tenth aspect, since the mounting portion is provided on the joining member, the size and density of the ink jet recording head can be reduced.

According to an eleventh aspect of the present invention, in the tenth aspect, the flow path forming substrate is made of a silicon single crystal substrate, and the joining member has a linear expansion coefficient close to a linear expansion coefficient of the silicon single crystal substrate. An ink jet recording head is formed of a material having the same.

In the eleventh aspect, even when the environmental temperature changes, no unnecessary stress or the like is generated in the piezoelectric element.

The twelfth aspect of the present invention is directed to the tenth or eleventh aspect.
Wherein the joining member is made of a material selected from the group consisting of glass ceramics and aluminum nitride.

In the twelfth aspect, the ink jet recording head is resistant to temperature changes.

According to a thirteenth aspect of the present invention, in any one of the tenth to twelfth aspects, the nozzle forming member is formed of substantially the same material as the flow path forming substrate. In the head.

In the thirteenth aspect, the joining of the nozzle plate is facilitated, and the manufacturing process can be simplified.

According to a fourteenth aspect of the present invention, in the tenth aspect, the flow path forming substrate and the nozzle forming member are formed of ceramics, and each layer of the piezoelectric element is formed by pasting or printing a green sheet. An ink jet recording head is characterized in that:

In the fourteenth aspect, the head chip can be easily manufactured.

According to a fifteenth aspect of the present invention, in any one of the tenth to fourteenth aspects, a reservoir connected to the pressure generating chamber is defined in the flow path forming substrate, and the nozzle forming member is An ink jet recording head is a nozzle plate having a nozzle opening.

In the fifteenth aspect, an ink jet recording head that discharges ink from the nozzle openings can be easily realized.

According to a sixteenth aspect of the present invention, in any one of the tenth to fourteenth aspects, the joining member has a reservoir portion that forms at least a part of a reservoir that communicates with the pressure generating chamber. The ink jet recording head is a substrate, wherein a reservoir formed in the flow path forming substrate is communicated with the pressure generating chamber, and the nozzle forming member is a nozzle plate having the nozzle opening.

In the sixteenth aspect, a relatively large reservoir can be easily formed, and the structure can be simplified.

According to a seventeenth aspect of the present invention, in the ink jet type according to the sixteenth aspect, the reservoir forming substrate has a space in a region facing the piezoelectric element so as not to hinder its movement. In the recording head.

In the seventeenth aspect, the mounting portion can be provided on the flow path forming substrate without hindering the driving of the piezoelectric element.

An eighteenth aspect of the present invention is the ink jet recording head according to the seventeenth aspect, wherein the piezoelectric element is sealed in the space of the reservoir forming substrate.

In the eighteenth aspect, the piezoelectric element is cut off from the outside, and the breakage of the piezoelectric element due to the external environment is prevented.

According to a nineteenth aspect of the present invention, in any one of the tenth to fourteenth aspects, the nozzle forming member includes a common ink chamber for supplying ink to the pressure generating chamber, the pressure generating chamber and the nozzle. The ink jet recording head is a flow path unit that forms a flow path that communicates with the opening.

In the nineteenth aspect, ink is ejected from the nozzle openings via the flow path unit.

According to a twentieth aspect of the present invention, in any one of the tenth to fourteenth aspects, an ink supply port communicating with the pressure generating chamber is opened on a surface of the flow path forming substrate on the piezoelectric element side. On the other hand, the ink jet recording head is characterized in that the joining member is provided with an ink supply flow path facing the ink supply port and communicating with each other.

In the twentieth aspect, the joining member also serves as a member for supplying ink, and the size can be further reduced.

According to a twenty-first aspect of the present invention, there is provided an ink jet recording apparatus comprising the ink jet recording head according to any one of the tenth to twentieth aspects.

According to the twenty-first aspect, it is possible to realize an ink jet recording apparatus in which the structure of the head is simplified and the manufacturing cost is reduced.

[0053]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on one embodiment.

(Embodiment 1) FIG. 1 is an exploded perspective view showing an ink jet recording head according to an embodiment of the present invention, and FIG. 2 is a cross-sectional structure of one of the pressure generating chambers in the longitudinal direction. FIG.

As shown in the figure, the flow path forming substrate 10 is formed of a silicon single crystal substrate having a plane orientation (110) in this embodiment. As the flow path forming substrate 10, usually 150 to 3
A thickness of about 00 μm is used.
Those having a thickness of about 0 to 280 μm, more preferably about 220 μm are suitable. This is because the arrangement density can be increased while maintaining the rigidity of the partition wall between the adjacent pressure generating chambers.

One surface of the flow path forming substrate 10 is an opening surface, and the other surface is formed with a 0.1 to 2 μm thick elastic film 50 made of silicon dioxide formed in advance by thermal oxidation.

On the other hand, the opening surface of the flow path forming substrate 10 is anisotropically etched on a silicon single crystal substrate,
Row 1 of pressure generating chambers 12 partitioned by a plurality of partition walls 11
3 are two rows and reservoirs 14 corresponding to each pressure generating chamber 12.
And an ink supply port 15 for communicating each pressure generating chamber 12 and each reservoir 14 with a constant fluid resistance. The elastic film 50 corresponding to each reservoir 14 is provided with an ink inlet 16 for supplying ink to the reservoir 14 from the outside.

Here, in the anisotropic etching, when a silicon single crystal substrate is immersed in an alkaline solution such as KOH, it is gradually eroded, and the first (111) plane perpendicular to the (110) plane and the first (111) plane The second (11) which forms an angle of about 70 degrees with the (111) plane and forms an angle of about 35 degrees with the above (110).
1) plane appears, and the etching rate of the (111) plane is about 1/18 as compared with the etching rate of the (110) plane.
This is performed using the property of being 0. By such anisotropic etching, two first (111)
Precision processing can be performed based on the depth processing of a parallelogram formed by two surfaces and two oblique second (111) surfaces, and the pressure generating chambers 12 can be arranged at high density.

In this 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 generating chamber 12 is provided on the flow path forming substrate 1.
It is formed by etching until it reaches the elastic film 50 almost through 0. Here, the elastic film 50 is
The amount attacked by the alkaline solution for etching the silicon single crystal substrate is extremely small. Each ink supply port 15 communicating with one end of each pressure generating chamber 12 is formed shallower than the pressure generating chamber 12. That is, the ink supply port 15
Is formed by etching (half-etching) the silicon single crystal substrate halfway in the thickness direction. Note that the half etching is performed by adjusting the etching time.

Also, on the opening side of the flow path forming substrate 10,
A nozzle plate 18 having a nozzle opening 17 communicating with the ink supply port 15 of each pressure generating chamber 12 on the side opposite to the ink supply port 15 is fixed via an adhesive or a heat welding film. The thickness of the nozzle plate 18 is, for example, 0.1 to 1
mm, the coefficient of linear expansion is 300 ° C. or less, for example, 2.5 to
4.5 [× 10 ⁻⁶ / ° C.] glass-ceramic,
Or made of non-rusting steel. The nozzle plate 18 entirely covers one surface of the flow path forming substrate 10 on one surface, and also serves as a reinforcing plate for protecting the silicon single crystal substrate from impact and external force. Further, the nozzle plate 18 is provided on the flow path forming substrate 1.
It may be made of a material which is substantially the same as 0, in other words, a material whose thermal expansion coefficient is substantially the same. In this case, since the deformation of the flow path forming substrate 10 and the nozzle plate 16 due to heat becomes substantially the same, a thermosetting adhesive or the like can be used, and the two can be easily joined.

Here, the size of the pressure generating chamber 12 for applying the ink droplet ejection pressure to the ink and the size of the nozzle opening 17 for ejecting the ink droplet depend on the amount of the ejected ink droplet, the ejection speed, and the ejection frequency. Optimized. For example,
When recording 360 ink droplets per inch, the nozzle openings 17 need to be formed with a diameter of several tens of μm with high accuracy.

On the other hand, the lower electrode film 60 having a thickness of, for example, about 0.2 μm and the piezoelectric film having a thickness of, for example, about 1 μm are formed on the elastic film 50 on the side opposite to the opening surface of the flow path forming substrate 10. Body membrane 7
0 and an upper electrode film 80 having a thickness of, for example, about 0.1 μm,
0. Here, the piezoelectric element 300 refers to a portion including the lower electrode film 60, the piezoelectric film 70, and the upper electrode film 80. In general, one of the electrodes of the piezoelectric vibration element 300 is used as a common electrode, and the other electrode and the piezoelectric film 70 are patterned for each of the pressure generating chambers 12. And
Here, a portion which is constituted by one of the patterned electrodes and the piezoelectric film 70 and in which a piezoelectric strain is generated by applying a voltage to both electrodes is referred to as a piezoelectric active portion 320. 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 the upper electrode film 80 is reversed for convenience of a drive circuit and wiring. In any case, the piezoelectric active portion is formed for each pressure generating chamber. Also, where
The combination of the piezoelectric element 300 and a diaphragm that generates a displacement by driving the piezoelectric element 300 is referred to as a piezoelectric actuator. In the example described above, the elastic film 50 and the lower electrode film 60 function as a diaphragm, but the lower electrode film may also serve as the elastic film.

Here, a process for forming the piezoelectric film 70 and the like on the flow path forming substrate 10 made of a silicon single crystal substrate will be described with reference to FIG.

As shown in FIG. 3A, first, a wafer of a silicon single crystal substrate serving as the flow path forming substrate 10 is
Thermal oxidation is performed in a diffusion furnace at 0 ° C. to form an elastic film 50 made of silicon dioxide.

Next, as shown in FIG. 3B, a lower electrode film 60 is formed by sputtering. Pt or the like is preferable as the material of the lower electrode film 60. This is because a piezoelectric film 70 described later, which is formed by a sputtering method or a sol-gel method,
After film formation, 600 to 10 in an air atmosphere or an oxygen atmosphere
This is because it is necessary to perform crystallization by firing at a temperature of about 00 ° C. That is, the material of the lower electrode film 60 must be able to maintain conductivity at such a high temperature and in an oxidizing atmosphere. In particular, when PZT is used for the piezoelectric film 70, the conductivity of the material by diffusion of PbO is increased. It is desirable that there is little change in sex, and Pt is preferred for these reasons.

Next, as shown in FIG. 3C, a piezoelectric film 70 is formed. The piezoelectric film 70 can be formed by a sputtering method, but in the present embodiment, a so-called sol in which a metal organic substance is dissolved and dispersed in a solvent is applied, dried, gelled, and further baked at a high temperature. A so-called sol-gel method for obtaining a piezoelectric film 70 made of a metal oxide is used. As a material for the piezoelectric film 70, a lead zirconate titanate (PZT) -based material is suitable when used in an ink jet recording head.

Next, as shown in FIG. 3D, an upper electrode film 80 is formed. The upper electrode film 80 only needs to be a material having high conductivity, and many metals such as Al, Au, Ni, and Pt, and a conductive oxide can be used. In the present embodiment, P
t is formed by sputtering.

Next, as shown in FIG. 3E, a piezoelectric element is provided for each of the pressure generating chambers 12.
The upper electrode film 80 and the piezoelectric film 70 are patterned.
FIG. 3E shows a case where the piezoelectric film 70 is patterned with the same pattern as the upper electrode film 80. However, as described above, the piezoelectric film 70 does not necessarily need to be patterned. This is because, when a voltage is applied using the pattern of the upper electrode film 80 as an individual electrode, an electric field is applied only between each upper electrode film 80 and the lower electrode film 60 which is a common electrode. This has no effect. However, in this case, it is necessary to apply a large voltage to obtain the same excluded volume. Therefore, it is preferable to pattern the piezoelectric film 70 as well. After that, the lower electrode film 60 may be patterned to remove, for example, the arm portions near the boundary portions on both sides of the pressure generation chamber 12, thereby improving the displacement amount.

Here, the patterning is performed by forming a resist pattern and then performing etching or the like.

The resist pattern is formed by, for example, applying a negative resist by spin coating or the like, and performing exposure, development, and baking using a mask having a predetermined shape. Of course, a positive resist may be used instead of the negative resist.

The etching is performed using a dry etching apparatus, for example, an ion milling apparatus, until the elastic film 50 made of a silicon dioxide film is exposed. After the etching, the resist pattern is removed using an ashing device or the like.

As the dry etching method, a reactive etching method or the like may be used other than the ion milling method. It is also possible to use wet etching instead of dry etching, but the patterning accuracy is somewhat inferior to the dry etching method, and the upper electrode film 8
Since the material of 0 is also limited, it is preferable to use dry etching.

The above is the film forming process. After forming the film in this manner, as shown in FIG. 3 (f), the silicon single crystal substrate is subjected to anisotropic etching with the above-described alkali solution to form the pressure generating chamber 12 and the like. In addition,
In the series of film formation and anisotropic etching described above, a number of chips are simultaneously formed on one wafer, and after completion of the process, each of the flow path forming substrates 10 having one chip size as shown in FIG. To divide.

In this embodiment, the head chip including the flow path forming substrate 10 and the nozzle plate 18 is a bonding member bonded to the flow path forming substrate as shown in FIGS. The head chip is fixed to a fixing member 120 for structurally holding and fixing the head chip. In addition, FIG.
FIG. 5 is an exploded perspective view and FIG. 5 is a plan view and a sectional view.

The fixing member 120 is made of a material such as glass ceramic or aluminum nitride having a coefficient of linear expansion close to the coefficient of linear expansion of the flow path forming substrate 10, and has a concave portion 121 for holding the flow path forming substrate 10 on one surface. Having.
The recess 121 may have a size enough to hold the head chip, but may have a size that fits around the head chip and holds it from the periphery.

At the joint position of the flow path forming substrate 10 in the concave portion 121, a wiring pattern 130 facing the pattern of the upper electrode film 80 facing each pressure generating chamber 12 is formed, and one end 131 of the wiring pattern 130 is formed. Of the upper electrode film 80 via the anisotropic conductive adhesive 135.
a is joined. On the other hand, the wiring pattern 130 extends through the fixing member 120 to the opposite surface, and the other end is an IC wiring portion 132.

A recess 122 is formed on the other end surface of the fixing member 120, and the driving IC 14
0 is implemented. Each terminal 141 of the driving IC 140 and the corresponding IC wiring section 132 are connected by wire bonding 145. The driving IC 140 and the wire bonding 145 are covered with the mold 150.

At both sides of the concave portion 122 of the fixing member 120 and at a position facing the ink introduction port 16 of the flow path forming substrate 10, an ink supply path 125 which is a through groove is formed. A flow path seal member 160 having a through hole 161 corresponding to each of the ink supply ports 16 and communicating with the ink supply path 125 is provided between the fixing member 120 and the flow path forming substrate 10. An ink supply unit (not shown) is provided at the other end of the ink supply path 125.

Further, the fixing member 120 includes a driving IC
A wiring for supplying a signal to 140 is provided, and one end of the wiring serves as a driving terminal 170. The driving terminal 170 is connected to a flexible printed circuit 180 for connection to an external device.

The ink jet recording head thus configured takes in ink from an ink inlet 16 connected to an external ink supply means (not shown) via an ink supply path 125, and supplies ink from the reservoir 14 to the nozzle opening 17. Is filled with ink, a voltage is applied between the lower electrode film 60 and the upper electrode film 80 according to a recording signal output from the driving IC 140 by a signal from an external device (not shown), and the elastic film 50 and the piezoelectric film By flexing and deforming 70, the pressure in the pressure generating chamber 12 increases, and ink droplets are ejected from the nozzle opening 17.

In the embodiment described above, the driving IC 140 is attached to the fixing member 120 for holding and fixing the nozzle tip.
By mounting the above, an ink jet recording head can be easily configured, and the space for mounting can be reduced.

The fixing member 120 is connected to the flow path forming substrate 10.
Since the piezoelectric element is formed of a material having a linear expansion coefficient similar to that of the piezoelectric element, no extra stress is generated in the piezoelectric element even when the environmental temperature changes.

(Embodiment 2) FIG. 6 shows a cross section of an ink jet recording head according to Embodiment 2.

This embodiment is the same as the above-described embodiment, except that the connection of the driving IC 140 with the wiring pattern of the fixing member 120 is performed not through wire bonding but through bumps.

That is, in the present embodiment, as shown in FIG. 6, the driving IC 140A has wiring bumps 141, and is directly thermocompression-bonded to the IC wiring portion 132 of the wiring pattern 130 of the fixing member 120 by ultrasonic wave. It can be mounted by bonding by crimping or the like.

A bump may be provided on the wiring section 132 side. Needless to say, the method of mounting the driving IC is not limited to these.

(Embodiment 3) FIG. 7 is a sectional view of an ink jet recording head according to Embodiment 3.

In the present embodiment, as shown in FIG. 7, the piezoelectric element 300 is basically provided in a region facing the pressure generating chamber 12, and the ink supply port is provided from the end opposite to the nozzle opening 17. 15 is extended to a region facing the same. Further, in a region corresponding to the vicinity of the end of the piezoelectric element 300 of the fixing member 120A, a through groove 126 is formed over the plurality of pressure generating chambers 12 arranged in parallel in the width direction. The vicinity of the end of the upper electrode film 80 opposite to the nozzle opening 17 and the IC wiring portion 132 provided on the upper surface of the fixing member 120A are connected to each other by connecting wires formed by wire bonding through the through grooves 126. This is the same as the first embodiment except that the connection is made at 146 and the piezoelectric element 300 and the driving IC 140 are connected.

In such a configuration, the through groove 126 is provided in the fixing member 120A, so that the connection wiring 146 connecting the upper electrode film 80 and the IC wiring portion 132 can be formed by wire bonding, and The element 300 and the driving IC 140 can be connected relatively easily. Also, of course, similarly to the above-described embodiment, the driving IC
Space can be saved.

In this embodiment, in order to provide the connection wiring 146, the plurality of pressure generating chambers 1 are attached to the fixing member 120A.
The two through-grooves 126 are provided, but the present invention is not limited to this. For example, an independent through-hole may be provided for each pressure generating chamber 12. In addition, the size is not particularly limited as long as the wire bonding 146 can be formed at least.

(Embodiment 4) FIG. 8 is a sectional view of an ink jet recording head according to Embodiment 4.

In this embodiment, as shown in FIG. 8, a wiring pattern 130A is formed in the opening of the fixing member 120B on the piezoelectric element 300 side so as to correspond to each piezoelectric element 300, and the wiring pattern 130A and the upper electrode are formed. The film 80 is joined via an anisotropic conductive adhesive. The connection wiring 146A connecting the wiring pattern 130A and the IC wiring portion 132 is formed by a thin film provided on the surface of the fixing member 120B on the side opposite to the piezoelectric element 300 and on the inner surface of the through groove 126A. Is the same as in the third embodiment.

The material of the connection wiring 146A is not particularly limited, and may be any material having conductivity.
In the present embodiment, a wiring having a two-layer structure is formed by using Au and Ti.

The method of forming the through groove 126A and the connection wiring 146A is not particularly limited, but in this embodiment, the through hole 126A and the connection wiring 146A are formed by the following method. FIG. 9 is a cross-sectional view of a main part of the pressure generating chamber 12 in a longitudinal direction showing a manufacturing process of the through groove and the driving wiring.
3 is a sectional view taken along line AA ′ of FIG.

First, as shown in FIG. 9A, a wiring pattern 130A is provided on the piezoelectric element 300 side of the fixing member 120B. Then, in the fixing member 120B in the region corresponding to the wiring pattern 130A, a through groove 126A is formed by anisotropic etching from the surface opposite to the piezoelectric element 300 in the same manner as the formation of the pressure generating chamber 12 described above. At this time, the etching is performed so that the surface of the through groove 126A where the connection wiring 146A is formed becomes the inclined surface 127.

Next, as shown in FIG. 9B, the surface of the fixing member 120B and the inclined surface 127 of the through groove 126A are formed.
The connection wiring 146A is formed, for example, by sputtering.
Is formed with a substantially uniform thickness.

Next, as shown in FIGS. 9C and 10, the wiring film 147 is patterned to
0 independently of the wiring pattern 130A and the IC wiring section 13
2 is formed.

Thus, the inclined surface 12 is formed in the through groove 126A.
7, the wiring film 147 to be the connection wiring 146A is formed and patterned, whereby the connection wiring 147 can be easily formed also on the inner surface of the through groove 126A. Therefore, the manufacturing process of the recording head can be simplified, and the manufacturing efficiency can be improved.

In this embodiment, the connection wiring 14
6A and the IC wiring portion 132 are formed as separate members,
The present invention is not limited to this. For example, the end of the connection wiring 146A may also serve as the IC wiring section 132.

(Embodiment 5) FIG. 11 is a sectional view of a main part of an ink jet recording head according to Embodiment 5.

In this embodiment, the fixing member 12 is used as a joining member to be joined to the piezoelectric element 300 side of the flow path forming substrate 10.
This is an example in which a reservoir forming substrate 150 having a space constituting at least a part of the reservoir is joined instead of 0, and a driving integrated circuit 140 is provided in a region of the reservoir forming substrate 150 opposite to the piezoelectric element 300. .

More specifically, as shown in FIG. 11, in the flow path forming substrate 10 of the present embodiment, the pressure generating chamber 12 and a common part of the pressure generating chambers 12 communicating with the reservoir portion 171 of the reservoir forming substrate 170 are provided. And a communication portion 19 which forms a part of a reservoir 175 which is an ink chamber of
Is connected to one end in the longitudinal direction of each pressure generating chamber 12 through an ink supply port 15A so as to have a constant flow path resistance.

A reservoir forming substrate 170 and a sealing plate 180 are joined to the flow path forming substrate 10 on the piezoelectric element 300 side. The reservoir forming substrate 170 is provided with the reservoir 17.
5 has a reservoir portion 171 which is at least partly connected to the communication portion 19 of the flow path forming substrate 10 to form a reservoir 175, and has one surface sealed with a sealing plate 180. The sealing plate 180 in the region facing the reservoir 175 is formed to be thinner than the other portions to form a flexible portion 175a having flexibility.
The deformation of 75a absorbs a change in the internal pressure of the reservoir 175. In the present embodiment, the sealing plate 180 is used as the reservoir 175 of the reservoir forming substrate 170.
Are formed only in the vicinity of the region corresponding to the above, and the surface of the reservoir forming substrate 170 is exposed in other portions.

The reservoir 175 has a sealing plate 180.
The ink is communicated with the outside through an ink introduction port 181 and an ink introduction path 172 formed through the reservoir forming substrate 170, and ink is supplied from outside through the ink introduction port 181 and the ink introduction path 172.

On the other hand, the piezoelectric element 3 of the reservoir forming substrate 20
A piezoelectric element holding portion 173 capable of sealing the space is provided in a region opposed to the piezoelectric element 300 in a state where a space that does not hinder the movement of the piezoelectric element 300 is secured.
At least the piezoelectric active part 320 is sealed in the piezoelectric element holding part 173.

Further, similarly to the case of the fixing member 120 described above, the reservoir forming substrate 170 has a through groove 174 extending over the row of the pressure generating chambers 12 in a region facing the upper electrode film 80 of the piezoelectric element 300. Are formed. And
From the upper electrode film 80 of each piezoelectric element 300 to the IC wiring portion 132A provided on the reservoir forming substrate 170, the through groove 1
74, the connection wiring 14 is connected by wire bonding.
6 is extended.

As described above, by mounting the driving integrated circuit 140 on the reservoir forming substrate 160 joined to the flow path forming substrate 10 and connecting the driving integrated circuit 140 to the piezoelectric element 300, the same as in the above-described embodiment, An ink jet recording head can be easily configured, and the mounting space can be saved.

In this embodiment, the connection wiring 146 is formed by wire bonding. However, the present invention is not limited to this. For example, similar to the fourth embodiment, a thin film may be formed between an IC wiring portion and a wiring pattern. May be formed. In the case of using a connection wiring made of such a thin film, for example, as shown in FIG. 12, the connection wiring 146A may be directly bonded to the upper electrode film 80 without providing a wiring pattern.

(Other Embodiments) Although the embodiments of the present invention have been described above, the basic configuration of the ink jet recording head is not limited to the above-described one.

For example, in the above-described embodiment, the driving integrated circuit is mounted on the fixing member or the reservoir forming substrate, which is the bonding member to be bonded to the flow path forming substrate 10, but is not limited to this. For example, a drive circuit may be formed directly on these joining members. This eliminates the need to separately mount the driving integrated circuit, and can further reduce the manufacturing cost.

Further, for example, in the above-described embodiment, the drive wiring is provided inside the joining member. However, the present invention is not limited to this. For example, the driving wiring may be provided to extend on the outer surface of the joining member. Is also good. In any case, by mounting the driving integrated circuit on the joining member or by forming the driving circuit, it is possible to realize the miniaturization and high density of the head.

Further, for example, in each of the above embodiments,
Although the driving integrated circuit is mounted on the joining member, the present invention is not limited to this. For example, the driving integrated circuit may be connected to external wiring such as a flexible cable without mounting the driving integrated circuit. . Even with such a configuration, the dimensions of the flow path forming substrate and the like can be reduced, and the recording head can be reduced in size.

Further, for example, in the first to fourth embodiments described above,
In the above, the head chip of the type in which the reservoir 14 is formed together with the pressure generating chamber 12 on the flow path forming substrate 10 is joined to the fixing member. However, the present invention is not limited to this. A head chip of a type in which units are provided on the flow path forming substrate 10 may be joined to a fixing member.

FIG. 13 is an exploded perspective view of a head chip according to the embodiment configured as described above, and FIG. 14 is a sectional view of a head using the head chip. In this embodiment, a nozzle plate 18 having a nozzle opening 17A is formed.
A and the flow path forming substrate 10A, the sealing plate 200, the common ink chamber forming plate 210, the thin plate 220, and the ink chamber side plate 230 are sandwiched, and the pressure generating chamber 12A and the nozzle opening are penetrated therethrough. A nozzle communication port 31 communicating with 17A is provided. That is, the common ink chamber 32 is defined by the sealing plate 200, the common ink chamber forming plate 210, and the thin plate 220, and each of the pressure generating chambers 12 </ b> A and the common ink chamber 32 are formed in the sealing plate 200. Ink communication hole 33
Are communicated through. The sealing plate 200 is also provided with an ink introduction hole 16A for introducing ink into the supply ink chamber 32 from outside. Also, the ink chamber side plate 2 located between the thin plate 220 and the nozzle plate 18A.
30 has a penetrating portion 3 at a position facing each supply ink chamber 32.
5 is formed to allow the thin plate 220 to absorb the pressure, which is generated at the time of discharging the ink droplets, toward the side opposite to the nozzle opening 17 </ b> A.
Unnecessary positive or negative pressure can be prevented from being applied to the other pressure generating chambers 12A via the common ink chamber 32. Note that the thin plate 220 and the ink chamber side plate 230 may be formed integrally.

As shown in FIG. 8, the head chip thus formed is fixed to the fixing member 1 similarly to the above-described embodiment.
Fixed to 20.

In each of the embodiments described above, a thin film type ink jet recording head which can be manufactured by applying a film forming and lithography process is exemplified. However, the present invention is not limited to this. May be used to form a piezoelectric film. Further, for example, a substrate may be formed by laminating ceramic sheets to form a pressure generating chamber, and a piezoelectric film may be formed by attaching a green sheet or by screen printing or the like. Further, the present invention can be applied to ink jet recording heads having various structures.

Further, in each of the embodiments described above, the upper electrode film is directly connected to the wiring pattern of the fixing member. However, the upper electrode film may be connected via a lead electrode connected to the upper electrode film.

As described above, the present invention can be applied to ink-jet recording heads having various structures, as long as the spirit of the present invention is not contradicted.

The ink jet recording head of each of the embodiments constitutes a part of a recording head unit having an ink flow path communicating with an ink cartridge and the like, and is mounted on an ink jet recording apparatus. FIG.
FIG. 1 is a schematic view showing an example of the ink jet recording apparatus.

As shown in FIG. 15, the recording head units 1A and 1B having the ink jet recording heads
Cartridges 2A and 2B constituting ink supply means are detachably provided. 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 main body 4 so as to be movable in the axial direction. I have. The recording head units 1A and 1B are, for example,
Each of them ejects a black ink composition and a color ink composition.

The driving force of the driving motor 6 is transmitted to the carriage 3 via a plurality of gears and a timing belt 7 (not shown), so that the carriage 3 on which the recording head units 1A and 1B are mounted moves along the carriage shaft 5. Moved. On the other hand, the apparatus main 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.

[0122]

As described above, in the present invention,
Since the connection with the external wiring is performed on the fixing member that holds and fixes the head chip, which is joined to the piezoelectric element side of the flow path forming substrate, or on the reservoir forming substrate that forms a part of the reservoir, The actuator and the ink jet recording head can be easily configured, and in particular, if the driving integrated circuit is mounted on these substrates, the mounting space can be saved. Further, since the fixing member is formed of a material having a linear expansion coefficient similar to the linear expansion coefficient of the flow path forming substrate, no extra stress is generated in the piezoelectric element even when the environmental temperature changes.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a head chip of an ink jet recording head according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the head chip according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view illustrating a thin-film manufacturing process according to the first embodiment of the present invention.

FIG. 4 is an exploded perspective view of the inkjet recording head according to the first embodiment of the present invention.

FIG. 5 is a plan view and a cross-sectional view of the inkjet recording head according to the first embodiment of the present invention.

FIG. 6 is a sectional view of an ink jet recording head according to a second embodiment of the invention.

FIG. 7 is a sectional view of an ink jet recording head according to Embodiment 3 of the present invention.

FIG. 8 is a sectional view of an ink jet recording head according to Embodiment 4 of the present invention.

FIG. 9 is a cross-sectional view illustrating a manufacturing process of the connection wiring according to the fourth embodiment of the present invention.

FIG. 10 is a cross-sectional view illustrating a manufacturing step of a connection wiring according to a fourth embodiment of the present invention.

FIG. 11 is a sectional view of an ink jet recording head according to a fifth embodiment of the present invention.

FIG. 12 is a sectional view showing a modification of the ink jet recording head according to Embodiment 5 of the present invention.

FIG. 13 is an exploded perspective view of a head chip according to another embodiment of the present invention.

FIG. 14 is a sectional view of an ink jet recording head according to another embodiment of the present invention.

FIG. 15 is a schematic view of an ink jet recording apparatus according to an embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 10 flow path forming substrate 12 pressure generating chamber 14 reservoir 15 ink supply port 16 ink introduction port 17 nozzle opening 18 nozzle plate 50 elastic film 60 lower electrode film 70 piezoelectric film 80 upper electrode film 120 fixing member 130 wiring pattern 140, 140A drive IC 160 Flow path sealing material 170 Driving terminal 180 Flexible printed circuit board

Claims (21)

[Claims] 1. An actuator device having a pressure generating chamber defined therein and a flow path forming substrate having a piezoelectric element on one surface side of the pressure generating chamber via a vibration plate, wherein: A bonding member to be bonded to the piezoelectric element side, wherein a mounting portion to which an external wiring is connected is provided in a region opposite to the piezoelectric element, and one end of the bonding member is mounted on the piezoelectric member; An actuator device, further comprising a driving wire connected to the piezoelectric element and the other end connected to the piezoelectric element. 2. The flow path forming device according to claim 1, wherein a contact portion connected to a driving electrode of the piezoelectric element is disposed on a surface of the flow path forming substrate on the bonding member side, and the flow path forming of the bonding member is performed. An actuator, wherein a connection portion at the other end of the drive wiring is arranged on the surface on the substrate side in correspondence with the contact portion, and the contact portion and the connection portion are pressure-bonded. apparatus. 3. The actuator device according to claim 1, wherein the driving wiring is provided in the joining member. 4. The drive member according to claim 1, wherein the joint member has a communication hole in a region corresponding to the piezoelectric element, the communication hole penetrating the joint member and communicating with the outside. An actuator device, wherein wiring is provided through the communication hole. 5. The driving line according to claim 4, wherein:
An actuator device formed by wire bonding. 6. The driving line according to claim 4, wherein:
An actuator device formed of a thin film. 7. The driving circuit according to claim 1, wherein a driving circuit for driving the piezoelectric element is mounted in a region of the joining member opposite to the piezoelectric element, and the driving wiring and the driving wiring are connected to each other. An actuator device, wherein the drive circuit is connected to a mounting unit. 8. The actuator device according to claim 7, wherein the drive circuit is formed directly on the joining member. 9. The actuator device according to claim 7, wherein the drive circuit is a semiconductor integrated circuit. 10. A nozzle forming member having a nozzle opening communicating with the pressure generating chamber is joined to the other surface side of the flow path forming substrate of the actuator device according to any one of claims 1 to 9. Inkjet recording head. 11. The method according to claim 10, wherein the flow path forming substrate is formed of a silicon single crystal substrate, and the joining member is formed of a material having a linear expansion coefficient close to a linear expansion coefficient of the silicon single crystal substrate. An ink jet recording head characterized by the following. 12. An ink jet recording head according to claim 10, wherein said joining member is made of a material selected from the group consisting of glass ceramics and aluminum nitride. 13. The method according to claim 10, wherein
An ink jet recording head, wherein the nozzle forming member is formed of substantially the same material as the flow path forming substrate. 14. The method according to claim 10, wherein the flow path forming substrate and the nozzle forming member are formed of ceramics,
An ink jet recording head, wherein each layer of the piezoelectric element is formed by pasting or printing a green sheet. 15. The method according to claim 10, wherein
An ink jet recording head, wherein a reservoir communicating with the pressure generating chamber is defined in the flow path forming substrate, and the nozzle forming member is a nozzle plate having the nozzle opening. 16. The method according to claim 10, wherein
The joining member is a reservoir forming substrate having a reservoir part that constitutes at least a part of the reservoir that communicates with the pressure generating chamber, and a reservoir that communicates with the pressure generating chamber is defined in the flow path forming substrate. An ink jet recording head, comprising: 17. The ink jet recording head according to claim 16, wherein the reservoir forming substrate has a space in a region facing the piezoelectric element so as not to hinder its movement. 18. The ink jet recording head according to claim 17, wherein the piezoelectric element is sealed in the space of the reservoir forming substrate. 19. The method according to claim 10, wherein
The nozzle forming member is a flow channel unit that forms a common ink chamber that supplies ink to the pressure generation chamber and a flow path that communicates the pressure generation chamber with the nozzle opening. Recording head. 20. The method according to claim 10, wherein
An ink supply port communicating with the pressure generating chamber is opened on the piezoelectric element side of the flow path forming substrate, while an ink supply path communicating with the ink supply port is provided on the joining member. An ink jet recording head, comprising: 21. An ink jet recording apparatus comprising the ink jet recording head according to claim 10.