JP2001162794A - Ink jet recording head and ink jet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet recording head and an ink jet recording apparatus in which nozzles can be arranged at high density and manufacturing cost is reduced. SOLUTION: The pressure generating chamber 12 is formed via a flow path forming substrate 10 in which a pressure generating chamber 12 communicating with a nozzle opening is defined, and a diaphragm 50 constituting a part of the pressure generating chamber 12.
A piezoelectric element 300 provided in a region corresponding to the pressure generating chamber 12 to generate a pressure change in the pressure generating chamber 12.
The bonding substrate 20 is bonded to the piezoelectric element 300 side, and the IC 22 is formed integrally with the bonding substrate 20, thereby reducing the number of components.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure generating chamber which communicates with a nozzle opening for discharging ink droplets, which is constituted by a vibrating plate. TECHNICAL FIELD The present invention relates to an ink jet recording head and an ink jet recording apparatus for ejecting ink droplets by means of a printer.

[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 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.

In such an ink jet recording head, a drive circuit for driving various integrated circuits (hereinafter referred to as IC), for example, a piezoelectric element is provided separately from a flow path forming substrate in which a pressure generating chamber is formed. Provided on the mounting substrate of
They were connected by wiring such as FPC.

[0008]

However, this F
The connection using a PC or the like has a problem that the number of components increases and the manufacturing cost increases. Further, since the number of wirings in the FPC is limited, there is a problem that there is a limit in increasing the number of nozzles.

In order to solve such a problem,
Although a circuit in which a drive circuit and the like are integrally formed on a flow path forming substrate has been proposed, a crystallization heat treatment is performed in a high-temperature oxygen atmosphere when forming a piezoelectric element on the flow path forming substrate. In addition, there is a problem that the characteristics of the IC are deteriorated and the manufacture is difficult.

SUMMARY OF THE INVENTION In view of such circumstances, an object of the present invention is to provide an ink jet recording head and an ink jet recording apparatus in which nozzles can be arranged at a high density and manufacturing cost is reduced.

[0011]

According to a first aspect of the present invention, there is provided a flow path forming substrate defining a pressure generating chamber communicating with a nozzle opening, and a part of the pressure generating chamber. A piezoelectric element provided in a region corresponding to the pressure generating chamber via a vibrating plate to form a pressure change in the pressure generating chamber, wherein the piezoelectric element of the flow path forming substrate is provided. An ink jet recording head is characterized in that it has a bonding substrate bonded to the side, and an IC is integrally formed on the bonding substrate.

In the first aspect, by integrally forming the IC on the bonding substrate bonded to the flow path forming substrate, the manufacturing process can be simplified, the number of components can be reduced, and the cost can be reduced. it can.

According to a second aspect of the present invention, in the first aspect, the bonding substrate is provided in a region facing the piezoelectric element.
An ink jet recording head is a sealing plate having a piezoelectric element holding portion capable of sealing the space while securing a space that does not hinder the movement.

In the second aspect, the breakage of the piezoelectric element due to the external environment is prevented.

A third aspect of the present invention is the ink jet recording head according to the first or second aspect, wherein the nozzle opening is formed in the bonding substrate.

In the third aspect, since the bonding substrate also serves as the nozzle plate, there is no need to separately provide a nozzle plate, and the cost can be reduced.

A fourth aspect of the present invention is the ink jet recording head according to the first or second aspect, wherein a reservoir for supplying ink to the pressure generating chamber is formed in the bonding substrate. It is in.

In the fourth aspect, since the bonding substrate also serves as the reservoir forming substrate, there is no need to provide a separate reservoir forming substrate, and the manufacturing cost can be reduced.

According to a fifth aspect of the present invention, there is provided an ink jet recording head according to any one of the first to fourth aspects, wherein the IC is a drive circuit for driving the piezoelectric element. .

In the fifth aspect, a drive circuit for driving the piezoelectric element can be formed relatively easily.

According to a sixth aspect of the present invention, in any one of the first to fourth aspects, the IC is a temperature detecting means for detecting a temperature of the head or a temperature control circuit for controlling the temperature. And an ink jet recording head.

In the sixth aspect, the temperature detecting means or the temperature control circuit can be formed relatively easily.

According to a seventh aspect of the present invention, in any one of the first to fourth aspects, the IC is ejection number detecting means for detecting the number of ejections of ink droplets ejected from the nozzle openings. The feature is the ink jet recording head.

In the seventh aspect, the number-of-discharges detecting means can be formed relatively easily.

According to an eighth aspect of the present invention, in any one of the second to fourth aspects, the IC is a humidity control circuit for controlling humidity detecting means for detecting humidity of the piezoelectric element holding portion. An ink jet recording head is characterized in that:

In the eighth aspect, the humidity control circuit can be formed relatively easily.

According to a ninth aspect of the present invention, in any one of the first to eighth aspects, the IC is provided on a surface of the bonding substrate opposite to a bonding surface with the flow path forming substrate. An ink jet recording head is characterized in that:

According to the ninth aspect, the wiring of the IC can be taken out from the surface of the bonding substrate.

According to a tenth aspect of the present invention, in any one of the first to eighth aspects, the IC is provided on a bonding surface side of the bonding substrate with the flow path forming substrate, and the piezoelectric element and the IC Are electrically connected by flip-chip mounting in the ink jet recording head.

In the tenth aspect, the IC and the piezoelectric element can be directly connected by joining the flow path forming substrate and the joining substrate.

According to an eleventh aspect of the present invention, in the tenth aspect, a connection wiring for connecting the IC and an external wiring is formed on the flow path forming substrate, and the IC and the connection wiring are flipped. An ink jet recording head is characterized by being electrically connected by chip mounting.

In the eleventh aspect, the IC and the connection wiring can be directly connected by joining the flow path forming substrate and the joining substrate.

The twelfth aspect of the present invention is directed to the tenth or eleventh aspect.
Wherein the IC and the piezoelectric element or the connection wiring are connected by an anisotropic conductive material.

In the twelfth aspect, the IC and the piezoelectric element or the connection wiring can be relatively easily and reliably connected.

A thirteenth aspect of the present invention is the ink jet recording head according to any one of the first to twelfth aspects, wherein the bonding substrate is formed of a silicon single crystal substrate.

In the thirteenth aspect, an IC is mounted on the bonding substrate.
Can be formed relatively easily and integrally with high precision.

According to a fourteenth aspect of the present invention, in any one of the first to thirteenth aspects, the pressure generating chamber is formed by anisotropic etching, and the respective layers constituting the diaphragm and the piezoelectric element are formed by film formation. And an ink jet recording head formed by a lithography method.

In the fourteenth aspect, an ink jet recording head having high-density nozzle openings can be manufactured in a large amount and relatively easily.

A fifteenth aspect of the present invention is an ink jet recording apparatus comprising the ink jet recording head according to any one of the first to fourteenth aspects.

According to the fifteenth aspect, it is possible to realize an ink jet recording apparatus having improved head characteristics.

[0041]

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

(Embodiment 1) FIG. 1 is an exploded perspective view showing an ink jet recording head according to Embodiment 1 of the present invention, and FIG. 2 is a longitudinal view of one pressure generating chamber of the ink jet recording head. It is a figure showing a section structure.

As shown in the figure, the flow path forming substrate 10 in which the pressure generating chamber 12 is formed is, for example, 150 μm to 1 mm.
And a plurality of barrier ribs 11 formed by anisotropic etching on the surface layer on one side.
A pressure generating chamber 12 is formed.

At one end in the longitudinal direction of each pressure generating chamber 12, an ink communication section 13 which is a relay chamber for connecting a reservoir 15 and the pressure generating chamber 12, which will be described later, has a width wider than that of the pressure generating chamber 12. It communicates via a narrow narrow portion 14. In addition, the ink communication portion 13 and the narrow portion 14 are
It is formed together with the pressure generating chamber 12 by anisotropic etching. The narrow portion 14 is for controlling the flow of ink into and out of the pressure generating chamber 12.

The anisotropic etching may be performed by either wet etching or dry etching. However, the pressure generating chamber 12 is formed by etching the silicon single crystal plate halfway in the thickness direction (half etching). It is formed shallow, and its depth can be adjusted by the etching time of the half etching.

In this embodiment, the ink communication unit 13
Is provided for each pressure generating chamber 12, but is not limited to this. For example, the ink communication portion 13 may be provided in each pressure generating chamber 1.
In this case, the ink communication unit 13 may form a part of a reservoir 15 described later.

On the other hand, on the other side of the flow path forming substrate 10,
A reservoir 15 is formed which communicates with each ink communication portion 13 and supplies ink to each pressure generating chamber 12. The reservoir 15 is formed from the other surface side of the flow path forming substrate 10 by anisotropic etching or the like using a predetermined mask.

An elastic film 50 having a thickness of 1 to 2 μm and made of an insulating layer such as zirconium oxide (ZrO ₂ ) is provided on such a flow path forming substrate 10. One surface of the elastic film 50 constitutes one wall surface of the pressure generating chamber 12.

Each pressure generating chamber 1 on such an elastic film 50
In the region opposed to 2, the thickness is, for example, about 0.5 μm
A lower electrode film 60, a piezoelectric layer 70 having a thickness of, for example, about 1 μm, and an upper electrode film 80 having a thickness of, for example, about 0.1 μm are laminated and formed by a process described later, and the piezoelectric element 30 is formed.
0. 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 of the electrodes of the piezoelectric element 300 is used as a common electrode, and the other electrode and the piezoelectric layer 70 are patterned for each of the pressure generating chambers 12. Here, a portion which is constituted by one of the patterned electrodes and the piezoelectric layer 70 and in which a piezoelectric strain is generated by applying a voltage to both electrodes is referred to as a piezoelectric active portion. In the present embodiment, the lower electrode film 60 is a common electrode of the piezoelectric element 300, and the upper electrode film 80 is an individual electrode of the piezoelectric element 300.
Even if this is reversed for convenience of the drive circuit and wiring, there is no problem.
In any case, the piezoelectric active portion is formed for each pressure generating chamber. Further, here, the piezoelectric element 300 and the elastic film whose displacement is generated by driving the piezoelectric element 300 are collectively referred to as a piezoelectric actuator.

The piezoelectric element 300 of the flow path forming substrate 10
On the other hand, in the present embodiment, a piezoelectric element holding portion capable of sealing this space on the elastic film 50 and the lower electrode film 60 in a state where a space that does not hinder the movement is secured in a region facing the piezoelectric element 300. The sealing plate 20 having 21 is joined. A predetermined IC, for example, a drive circuit 22 for driving the piezoelectric element 300 in the present embodiment is integrally formed near one end of the sealing plate 20 on the side of the bonding surface with the flow path forming substrate 10. Have been.

In the present embodiment, the sealing plate 20 is made of, for example, a silicon single crystal substrate, and the drive circuit 22 is a semiconductor integrated circuit formed integrally with the sealing plate 20 by a semiconductor process. Although the lower electrode film is left in the region corresponding to the drive circuit 22, the lower electrode film is a discontinuous lower electrode film 61 that is discontinuous with the lower electrode film 60 of the piezoelectric element 300. It has become.

The drive circuit 22 and the upper electrode film 80 of the piezoelectric element 300 are connected via a lead electrode 90. For example, in the present embodiment, the lead electrode 90 extends from the upper electrode film 80 to the vicinity of the discontinuous lower electrode film 61 on the elastic film 50, and the end portion and the drive circuit 22 are anisotropic. They are electrically connected via a connection layer 110 made of a conductive material (AFC) or the like.

In this embodiment, as shown in FIG. 3, the drive circuit 22 and the external wiring 1 such as an FPC are disposed on the flow path forming substrate 10 near the end of the pressure generating chamber 12 in the juxtaposition direction.
The connection wiring 130 is formed to connect to the drive circuit 22. The drive circuit 22 and the connection wiring 130 are electrically connected to each other through the connection layer 110, similarly to the lead electrode 90.

In the present embodiment, the sealing plate 20 is provided with a nozzle opening 23 communicating with each pressure generating chamber 12, and also serves as a nozzle plate. Further, the nozzle opening 23 and the pressure generating chamber 12 are formed by the elastic film 50.
The lower electrode film 60 is communicated via a nozzle communication hole 51 provided by removing the lower electrode film 60.

Here, the manufacturing process of the ink jet recording head of this embodiment, in particular, the process of forming the pressure generating chamber 12 in the flow path forming substrate 10 and the formation of the piezoelectric element 300 in the region corresponding to the pressure generating chamber 12 The steps to be performed will be described. 4 to 6 are cross-sectional views of the pressure generating chamber 12 in the longitudinal direction.

First, as shown in FIG. 4A, anisotropic etching is performed on one side of a silicon single crystal plate serving as the flow path forming substrate 10 using a mask of a predetermined shape made of, for example, silicon oxide. Thereby, the pressure generating chamber 12, the ink communication portion 13, and the narrow portion 14 are formed.

Next, as shown in FIG. 4B, the pressure generating chamber 12 formed in the flow path forming substrate 10 and the ink communication section 1 are formed.
3 and the narrow portion 14 are filled with the sacrificial layer 100. For example,
In the present embodiment, after the sacrificial layer 100 is formed over the entire surface of the flow path forming substrate 10 with substantially the same thickness as the depth of the pressure generating chambers 12 and the like, the sacrifice layer 100 except for the pressure generating chambers 12, the ink communication part 13, and the narrow part 14 Was formed by removing the sacrificial layer 100 by chemical mechanical polishing (CMP).

The material of the sacrificial layer 100 is not particularly limited. For example, polysilicon or phosphorus-doped silicon oxide (PSG) may be used. In the present embodiment, PSG having a relatively high etching rate is used. .

The method of forming the sacrificial layer 100 is not particularly limited. For example, ultrafine particles of 1 μm or less
A method called a gas deposition method or a jet molding method in which a film is formed by colliding with a substrate at high speed by the pressure of a gas such as e) may be used. In this method, the pressure generating chamber 12 and the ink communication section 13
In addition, the sacrifice layer 100 can be partially formed only in a region corresponding to the narrow portion 14.

Next, as shown in FIG. 4C, an elastic film 50 is formed on the flow path forming substrate 10 and the sacrificial layer 100.
In the present embodiment, the protective film 5 serving as a mask when forming the reservoir 15 is formed on the other surface of the flow path forming substrate 10.
5 is formed. For example, in the present embodiment, after forming a zirconium layer on both surfaces of the flow path forming substrate 10, 500 to 120
The elastic film 50 and the protective film 55 made of zirconium oxide were thermally oxidized in a diffusion furnace at 0 ° C.

The materials of the elastic film 50 and the protective film 55 are not particularly limited as long as they are not etched in the step of forming the reservoir 15 and the step of removing the sacrificial layer 100. Further, the elastic film 50 and the protective film 55
May be formed of different materials. further,
The protective film 55 may be formed in any step as long as it is before the reservoir 15 is formed.

Next, a piezoelectric element 300 is formed on the elastic film 50 corresponding to each pressure generating chamber 12.

The steps for forming the piezoelectric element 300 include:
First, as shown in FIG. 4D, the lower electrode film 60 is formed over the entire surface of the flow path forming substrate 10 on the pressure generating chamber 12 side by sputtering, and is patterned into a predetermined shape. Etc. are formed. Preferable materials for the lower electrode film 60 include platinum and iridium. This is because it is necessary to crystallize a piezoelectric layer 70 described later, which is formed by a sputtering method or a sol-gel method, by firing at a temperature of about 600 to 1000 ° C. in an air atmosphere or an oxygen atmosphere after the film formation. Because. That is, the material of the lower electrode film 60 must be able to maintain conductivity under such a high temperature and oxidizing atmosphere. In particular, when the piezoelectric layer 70 is made of lead zirconate titanate (PZT), It is desirable that the change in conductivity due to diffusion of lead oxide is small, and for these reasons, platinum and iridium are preferred.

Next, as shown in FIG. 5A, a piezoelectric layer 70 is formed. For example, in the present embodiment, a so-called sol in which a metal organic material is dissolved and dispersed in a catalyst is applied and dried to form a gel, and then fired at a high temperature to obtain a piezoelectric layer 70 made of a metal oxide. Formed by using As a material for the piezoelectric layer 70, a PZT-based material is suitable when used in an ink jet recording head. The method for forming the piezoelectric layer 70 is not particularly limited. For example, the piezoelectric layer 70 may be formed by a spin coating method such as a sputtering method or a MOD method (organic metal thermal coating decomposition method).

Further, a method of forming a precursor film of lead zirconate titanate by a sol-gel method, a sputtering method, a MOD method, or the like, and then growing the crystals at a low temperature by a high-pressure treatment in an alkaline aqueous solution may be used. Good.

In any case, in the piezoelectric layer 70 formed as described above, the crystal is preferentially oriented unlike the bulk piezoelectric, and in the present embodiment, the crystal is formed in the piezoelectric layer 70. It is formed in a column shape. Note that the preferential orientation refers to a state in which a crystal orientation direction is not disordered and a specific crystal plane is oriented in a substantially constant direction. In addition, a crystal having a columnar thin film refers to a state in which substantially columnar crystals are gathered in a plane direction with their central axes substantially aligned in the thickness direction to form a thin film. Of course, it may be a thin film formed of preferentially oriented granular crystals. The thickness of the piezoelectric layer manufactured in the thin film process is generally 0.2 to 5 μm.

Next, as shown in FIG. 5B, an upper electrode film 80 is formed. The upper electrode film 80 only needs to be a material having high conductivity, and can use many metals such as aluminum, gold, nickel, and platinum, and a conductive oxide. In the present embodiment, platinum is formed by sputtering.

Next, as shown in FIG. 5C, only the piezoelectric layer 70 and the upper electrode film 80 are etched to pattern the piezoelectric element 300. In the present embodiment,
At the same time, the ink communication portion 13 in the longitudinal direction of the pressure generating chamber 12
The nozzle communication hole 51 is formed by patterning the elastic film 50 and the lower electrode film 60 near the end opposite to the above.

Next, as shown in FIG. 5D, a lead electrode 90 is formed over the entire surface of the flow path forming substrate 10 and patterned for each piezoelectric element 300 to form an upper electrode for each piezoelectric element 300. A lead electrode 90 extending from the film 80 onto the elastic film 50 is formed. Although described in detail later, the end of the lead electrode 90 extends to a region facing the drive circuit 22 provided integrally with the sealing plate 20.

Next, as shown in FIG. 6A, a region which becomes the reservoir 15 of the protective film 55 provided on the surface of the flow path forming substrate 10 opposite to the pressure generating chamber 12 is removed by patterning. The reservoir 15 is formed by performing anisotropic etching, for example, wet etching, from the opening 56 to reach the ink communicating portion 13. In the present embodiment, the reservoir 15 is formed after the piezoelectric element 300 is formed. However, the present invention is not limited to this, and the reservoir 15 may be formed in any process.

Thereafter, as shown in FIG. 6B, the sacrificial layer 100 is removed from the reservoir 15 by wet etching or etching with steam. In this embodiment,
Since PSG is used as the material of the sacrificial layer 100,
Etching was performed using a hydrofluoric acid aqueous solution. When polysilicon is used, etching can be performed with a mixed aqueous solution of hydrofluoric acid and nitric acid or an aqueous solution of potassium hydroxide.

Through the above steps, the pressure generating chamber 12 and the piezoelectric element 300 are formed.

Thereafter, the piezoelectric element 30 of the flow path forming substrate 10
On the 0 side, in this embodiment, the sealing plate 20 is bonded on the lower electrode film 60. At this time, for example, an anisotropic conductive material (AF) is provided near the end of the lead electrode 90 and the end of the wiring electrode 130.
C) and the like, and the lead electrode 90 is formed simultaneously with the joining of the flow path forming substrate 10 and the sealing plate 20.
In addition, the connection wiring 130 and the drive circuit 22 are electrically connected.

The method for forming the sealing plate 20 in which the drive circuit 22 is integrally formed is not particularly limited. For example, after the drive circuit 22 is integrally formed in a semiconductor process, the piezoelectric element holding portion 21 and the The nozzle opening 23 may be formed by etching or the like.

The ink jet recording head thus manufactured according to the present embodiment takes in ink from an external ink supply means (not shown) into the reservoir 15 and supplies the ink to the reservoir 15.
After filling the inside from the nozzles 23 with the ink, the lower electrode film 60 and the upper electrode film 80 corresponding to the pressure generating chambers 12 are formed according to the recording signal output from the external wiring 120 via the drive circuit 22. And apply a voltage between
By bending and deforming the elastic film 50, the lower electrode film 60, and the piezoelectric layer 70, the pressure in each pressure generating chamber 12 increases, and ink droplets are ejected from the nozzle openings 23.

In the ink jet recording head having such a configuration, the drive circuit 22 for driving the piezoelectric element 300 is formed on the sealing plate 20, so that the number of components can be reduced and the manufacturing process can be reduced. It can be simplified and cost can be reduced.

Further, by joining the sealing plate 20 and the flow path forming substrate 10, the lead electrodes 90 and the connection wirings 13 are formed.
0 and the drive circuit 22 can be electrically connected, so that the number of connection wirings 130 can be reduced, and even if the number of nozzle openings 23 is increased and the nozzles 23 are arranged at high density, they can be taken out by FPC or the like. it can.

For example, as shown in FIG. 7, a plurality of drive circuits 22 are provided on the sealing plate 20, and the pressure generating chambers 12 and the piezoelectric A row of elements 300 may be provided. With such a configuration, the wiring from the piezoelectric elements 300 arranged at a high density can be easily taken out by the external wiring 120 such as an FPC.

In this embodiment, the ink communication unit 13
And each pressure generating chamber 12 and the reservoir 1 through the narrow portion 14.
5 is communicated, but the invention is not limited to this. For example, as shown in FIG. 8A, each pressure generating chamber 12 and the reservoir 15 may be directly communicated.

In the present embodiment, the narrow portion 14 is formed to have a smaller width than the pressure generating chamber 12 to control the flow of ink into and out of the pressure generating chamber 12. However, the present invention is not limited to this. For example, as shown in FIG.
The narrow portion 14A may have the same width as 2 and a depth adjusted.

(Embodiment 2) FIG. 9 is a sectional view of an ink jet recording head according to Embodiment 2.

This embodiment is an example in which a drive circuit 22A is provided on the surface of the sealing plate 20A opposite to the flow path forming substrate 10A.

More specifically, as shown in FIG. 9, rows of pressure generating chambers 12 arranged in the width direction are arranged on the flow path forming substrate 10A such that the longitudinal ends thereof face each other. Have been. A piezoelectric element 300 is formed on one surface of the flow path forming substrate 10A via an elastic film 50, and a nozzle plate 3 having a nozzle opening 23A formed on the other surface.
0 is joined.

The piezoelectric element 30 of the flow path forming substrate 10A
On the 0 side, a sealing plate 20A for sealing the piezoelectric element 300 is joined. In the present embodiment, the sealing plate 20A is used to drive the piezoelectric element 300 to the surface of the sealing plate 20A opposite to the flow path forming substrate 10A. The drive circuit 22A is provided integrally.

Further, in a region of the sealing plate 20A facing the peripheral wall of the pressure generating chamber 12, a through groove 24 is provided in the direction in which the pressure generating chambers 12 are juxtaposed, and through this through groove 24. The drive circuit 22A and each lead electrode 90 are connected by a wiring 140 extended by wire bonding or the like.

Further, outside the through-groove 24 of the sealing plate 20A, a reservoir 15A communicating with the pressure generating chamber 12 through each ink communicating portion 13 and an ink supply path 16 for supplying ink to the reservoir 15A are formed. Have been.

The compliance substrate 40 comprising a flexible sealing film 41 and a fixing plate 42 is further provided on the sealing plate 20A in a region facing the reservoir 15A.
Are joined. The region facing the reservoir 15A is sealed only with the sealing film 41, and serves as a compliance portion 43 that absorbs a pressure change in the reservoir 15A.

Also in this configuration, as in the above-described embodiment, the number of parts can be reduced, the manufacturing process can be simplified, and the cost can be reduced.
Further, the wiring can be easily pulled out from the piezoelectric element 300.

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

For example, in the above embodiment, the sealing plate 20
And 20A are provided integrally with the drive circuits 22 and 22A for driving the piezoelectric element 300. However, the present invention is not limited to this. For example, a temperature detecting means for detecting the temperature of the head on the sealing plate or its temperature May be provided with a temperature control circuit or the like for controlling the temperature. Alternatively, it may be a number-of-ejections detecting means for detecting the number of ejections of the ink droplets ejected from the nozzle openings, a humidity control circuit for controlling humidity detecting means for detecting the humidity of the piezoelectric element holding portion, or the like. Is also good. In any case, by providing these integrally with the sealing plate, the number of components can be reduced and the cost can be reduced as in the above-described embodiment.

In the above embodiment, the IC is formed integrally with the sealing plate. However, the present invention is not limited to this.
If the substrate is bonded to the piezoelectric element side of the flow path forming substrate,
Any substrate may be used.

In each of the above embodiments, a thin-film type ink jet recording head manufactured by applying a film forming and lithography process has been described as an example. However, the present invention is not limited to this. The present invention can also be applied to a thick-film type ink jet recording head formed by a method such as attaching a sheet.

The ink jet recording head of each of these 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. 10, the recording head units 1A and 1B having the ink jet recording head are
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, a platen 8 is provided on the apparatus main body 4 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.

[0096]

As described above, in the present invention, various ICs such as a drive circuit for driving the piezoelectric element are integrally provided on the sealing plate, so that the manufacturing process can be simplified and the number of parts can be reduced. Can be reduced, and costs can be reduced.

In particular, when a drive circuit for driving the piezoelectric element is integrally provided on the side of the sealing plate joined to the flow path forming substrate, the lead electrode from the piezoelectric element is directly connected to the drive circuit. The number of electrodes that can be connected to the mounting substrate can be reduced. Therefore, even if the nozzle openings are densely arranged, the wiring can be easily taken out.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing an ink jet recording head according to a first embodiment of the present invention.

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

FIG. 3 is a top view schematically showing the ink jet recording head according to the first embodiment of the present invention.

FIG. 4 is a cross-sectional view illustrating a manufacturing process of the ink jet recording head according to the first embodiment of the present invention.

FIG. 5 is a cross-sectional view illustrating a manufacturing process of the ink jet recording head according to Embodiment 1 of the present invention.

FIG. 6 is a cross-sectional view illustrating a manufacturing process of the ink jet recording head according to Embodiment 1 of the present invention.

FIG. 7 is a top view showing a modification of the ink jet recording head according to the first embodiment of the present invention.

FIG. 8 is a sectional view showing a modification of the ink jet recording head according to the first embodiment of the present invention.

FIG. 9 is a sectional view showing an ink jet recording head according to a second embodiment of the present invention.

FIG. 10 is a schematic diagram of an ink jet recording apparatus according to an embodiment of the present invention.

[Explanation of symbols]

 10, 10A Flow path forming substrate 11 Partition wall 12 Pressure generating chamber 13 Ink communicating part 14 Narrow part 15 Reservoir 20 Sealing plate 21 Piezoelectric element holding part 22 Drive circuit 23 Nozzle opening 50 Elastic film 60 Lower electrode film 70 Piezoelectric layer 80 Above Electrode film 300 Piezoelectric element

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C057 AF34 AF35 AF37 AF93 AG12 AG44 AG83 AG84 AG90 AK07 AK15 AP02 AP11 AP24 AP34 AP51 AQ02 BA04 BA14

Claims (15)

[Claims] A pressure generating chamber that defines a pressure generating chamber that communicates with a nozzle opening; and a diaphragm that is provided in a region corresponding to the pressure generating chamber via a vibration plate that forms a part of the pressure generating chamber. An ink jet recording head comprising: a piezoelectric element that causes a pressure change in the pressure generating chamber; and a bonding substrate bonded to the piezoelectric element side of the flow path forming substrate, wherein an IC is mounted on the bonding substrate. An ink jet recording head, which is formed integrally. 2. The sealing device according to claim 1, wherein the bonding substrate has a piezoelectric element holding portion capable of sealing the space in a region facing the piezoelectric element in a state in which a space that does not hinder the movement is secured. An ink jet recording head, which is a stop plate. 3. The ink jet recording head according to claim 1, wherein the nozzle openings are formed in the bonding substrate. 4. The ink jet recording head according to claim 1, wherein a reservoir for supplying ink to the pressure generating chamber is formed in the bonding substrate. 5. The method according to claim 1, wherein
C is a drive circuit for driving the piezoelectric element. 6. The method according to claim 1, wherein
C is a temperature detecting means for detecting the temperature of the head or a temperature control circuit for controlling the temperature. 7. The method according to claim 1, wherein
C is an ejection frequency detecting means for detecting the number of ejections of ink droplets ejected from the nozzle openings. 8. The method according to claim 2, wherein
C is a humidity control circuit for controlling humidity detecting means for detecting the humidity of the piezoelectric element holding section. 9. The method according to claim 1, wherein
An ink jet recording head, wherein C is provided on a surface of the bonding substrate opposite to a bonding surface with the flow path forming substrate. 10. The IC according to claim 1, wherein the IC is provided on a bonding surface side of the bonding substrate with the flow path forming substrate, and the piezoelectric element and the IC are electrically connected by flip chip mounting. An ink jet recording head, which is connected to a recording medium. 11. The flow path forming substrate according to claim 10, wherein a connection wiring for connecting the IC and an external wiring is formed, and the IC and the connection wiring are electrically connected by flip-chip mounting. An ink jet recording head characterized in that: 12. The method according to claim 10, wherein
C. The ink jet recording head, wherein C and the piezoelectric element or the connection wiring are connected by an anisotropic conductive material. 13. The ink jet recording head according to claim 1, wherein the bonding substrate is formed of a silicon single crystal substrate. 14. The pressure generating chamber according to claim 1, wherein the pressure generating chamber is formed by anisotropic etching, and the respective layers constituting the diaphragm and the piezoelectric element are formed by film formation and lithography. An ink jet recording head, characterized in that: 15. An ink jet recording apparatus comprising the ink jet recording head according to claim 1.