JPH11157061A - Ink jet type recording head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the breakdown generated by the overcurrent in a contact hole or the dielectric breakdown generated by the migration caused by the overcurrent. SOLUTION: A recording head is provided with a piezoelectric vibrator with a piezoelectric body active section 320 constituted of a piezoelectric body layer 70 and an upper electrode 80 formed on the surface of a vibration plate, at least an upper face of which forms a part of a pressure generating chamber communicated with a nozzle hole, and a contact section 91 working as a connecting section of a lead electrode 100 for applying voltage to the piezoelectric body active section 320 with the piezoelectric body active section 320. In that case, the contact section 91 is extended along the direction crossing the current outflowing direction from the contact section 91 to the upper electrode 80, and the current concentration at the time of flowing current from the lead electrode 100 to the contact section 91 is dispersed along the extension direction of the contact section 91 to prevent the concentration of current into a part of the contact section 91.

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 is in communication with a nozzle opening for discharging ink droplets, and which is constituted by a vibrating plate. The present invention relates to an ink jet recording head that ejects ink droplets by displacement of a layer.

[0002]

2. Description of the Related Art A part of a pressure generating chamber which communicates with a nozzle opening for discharging ink droplets is constituted by a vibrating plate. There are two types of ink-jet recording heads that eject ink droplets from a piezoelectric vibrator, one that uses a longitudinal vibration mode piezoelectric vibrator that expands and contracts in the axial direction of the piezoelectric vibrator, and the other that uses a flexural vibration mode piezoelectric vibrator. Has been put to practical use.

In the former method, the volume of the pressure generating chamber can be changed by bringing the end face of the piezoelectric vibrator into contact with the vibrating plate, so that a head suitable for high-density printing can be manufactured. A complicated process of cutting the piezoelectric vibrators into a comb-tooth shape in accordance with the arrangement pitch of the nozzle openings, and a work of positioning and fixing the separated piezoelectric vibrators in the pressure generating chambers, which complicates the manufacturing process. There is.

On the other hand, in the latter, a piezoelectric vibrator 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. However, due to the use of flexural vibration, a certain area is required, and there is a problem 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 this piezoelectric material layer is cut into a shape corresponding to the pressure generating chambers by lithography, and a piezoelectric vibrator is formed so as to be independent for each pressure generating chamber.

[0006] According to this, the work of attaching the piezoelectric vibrator to the diaphragm is not required, and the precision of the lithography method is used.
In addition to the fact that the piezoelectric vibrator can be manufactured by a simple and simple method, there is an advantage that the thickness of the piezoelectric vibrator can be reduced and high-speed driving is possible.

In this case, the piezoelectric vibrator corresponding to each pressure generating chamber is driven by providing at least only the upper electrode for each pressure generating chamber while the piezoelectric material layer is provided on the entire surface of the vibration plate. However, due to the problem of the amount of displacement per unit drive voltage and the stress applied to the piezoelectric layer at the portion facing the pressure generating chamber and the portion straddling the outside thereof, the piezoelectric active portion composed of the piezoelectric layer and the upper electrode is required. It is desirable that the pressure sensor be provided in a region facing the pressure generating chamber or be formed so that at least one end portion does not come out of the region facing the pressure generating chamber.

Further, in a recording head using such a flexural mode piezoelectric vibrator, the piezoelectric vibrators corresponding to the respective pressure generating chambers are covered with an insulator layer, and each of the piezoelectric vibrators is covered with the insulator layer. A window (hereinafter, referred to as a contact hole) is provided for each pressure generating chamber to form a connection portion with a lead electrode that supplies a voltage for driving,
A connection portion between each piezoelectric vibrator and the lead electrode is formed in the contact hole.

[0009]

However, since the upper electrode is formed so thin that it does not hinder the deformation of the diaphragm, the resistance is large, whereas the lead electrode reliably supplies power to the piezoelectric layer. Therefore, it is necessary to reduce the resistance, and since the difference between the two resistances is large, the current is concentrated near the end of the contact hole, and the overcurrent destroys the contact hole or migrates due to the overcurrent. There is a problem that the layer causes dielectric breakdown.

In view of such circumstances, an object of the present invention is to provide an ink jet recording head capable of preventing breakdown due to overcurrent in a contact hole and insulation breakdown due to migration due to overcurrent. I do.

[0011]

According to a first aspect of the present invention, there is provided:
A vibrating plate constituting a part of a pressure generating chamber communicating with the nozzle opening, at least an upper surface of which acts as a lower electrode, a piezoelectric layer formed on the surface of the vibrating plate, and a piezoelectric layer formed on the surface of the piezoelectric layer A piezoelectric vibrator comprising a piezoelectric active part comprising an upper electrode; a lead electrode for applying a voltage to the piezoelectric active part; and a contact part serving as a connection part between the piezoelectric active part and the lead electrode. In the ink jet recording head, the contact portion extends along a direction intersecting a direction in which a current flows from the contact portion to the upper electrode.

In the first aspect, the current density when the current flows from the lead electrode to the contact portion is dispersed along the extending direction of the contact portion, and the current is prevented from being concentrated on a part of the contact portion. You.

According to a second aspect of the present invention, in the first aspect, an insulator layer is formed on an upper surface of the piezoelectric active portion,
The contact portion is formed in a contact hole formed in the insulator layer.

In the second aspect, the concentration of current when applying a voltage to the piezoelectric active portion in the contact hole is reduced, and the breakage of the piezoelectric layer around the contact hole is prevented.

According to a third aspect of the present invention, in the second aspect, the contact hole is a long hole which is elongated in a direction intersecting a current flowing direction from the contact hole. Ink-jet recording head.

In the third aspect, the current when applying a voltage to the piezoelectric active portion in the contact hole is dispersed along the longitudinal direction, so that the piezoelectric layer is prevented from being broken around the contact hole. You.

According to a fourth aspect of the present invention, in the second aspect, the contact hole comprises a plurality of holes, and is provided in a direction intersecting a direction in which current flows from the contact hole. The ink jet recording head is characterized in that:

In the fourth aspect, the current when applying a voltage to the piezoelectric active portion in the contact hole is dispersed in each contact hole, so that the breakage of the piezoelectric layer around the contact hole is prevented.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects, a narrow portion having a width smaller than other portions is provided near the contact portion of the upper electrode. Ink-jet recording head.

In the fifth aspect, current flows from the contact portion toward the narrow portion of the upper electrode.

According to a sixth aspect of the present invention, in any one of the first to fifth aspects, the pressure generating chamber is formed by anisotropic etching on a silicon single crystal substrate, and each layer of the piezoelectric vibrator is formed by film formation. And an ink jet recording head formed by a lithography method.

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

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on a first embodiment.

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

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 an elastic film 50 having a thickness of 1 to 2 μm and made of silicon dioxide previously formed by thermal oxidation.

On the other hand, the silicon single crystal substrate is anisotropically etched on the opening surface of the flow path forming substrate
A nozzle opening 11 and a pressure generating chamber 12 are formed.

Here, in the anisotropic etching, when the silicon single crystal substrate is immersed in an alkaline solution such as KOH, the substrate 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. The amount of the elastic film 50 that is attacked by the alkaline solution for etching the silicon single crystal substrate is extremely small.

On the other hand, each nozzle opening 11 communicating with one end of each pressure generating chamber 12 is formed narrower and shallower than the pressure generating chamber 12. That is, the nozzle opening 11 is formed by partially etching (half-etching) the silicon single crystal substrate in the thickness direction. In addition,
Half etching is performed by adjusting the etching time.

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 11 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 11 need to be formed with a groove width of several tens of μm with high accuracy.

Further, each pressure generating chamber 12 and a common ink chamber 31 described later are connected to each pressure generating chamber 1 of the sealing plate 20 described later.
The ink is supplied from a common ink chamber 31 through the ink supply communication port 21 formed at a position corresponding to one end of the pressure generation chamber 12. Distributed to

The sealing plate 20 is provided with an ink supply communication port 21 corresponding to each of the pressure generating chambers 12 described above, and has a thickness of, for example, 0.1 to 1 mm and a linear expansion coefficient of 300 ° C. or less. , For example, 2.5-4.5 [× 10 ⁻⁶ / ° C.]. In addition, the ink supply communication port 21
May be a single slit or a plurality of slits crossing the vicinity of the ink supply side end of each pressure generating chamber 12. The sealing plate 20 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. The other surface of the sealing plate 20 forms one wall surface of the common ink chamber 31.

The common ink chamber forming substrate 30 forms the peripheral wall of the common ink chamber 31, and is formed by punching a stainless steel plate having an appropriate thickness according to the number of nozzles and the ink droplet ejection frequency. . In the present embodiment, the thickness of the common ink chamber forming substrate 30 is 0.2 mm.

The ink chamber side plate 40 is made of a stainless steel substrate, and one surface thereof constitutes one wall surface of the common ink chamber 31. In the ink chamber side plate 40, a thin wall 41 is formed by forming a concave portion 40a by half etching on a part of the other surface, and an ink introduction port 42 for receiving ink supply from the outside is punched and formed. ing. The thin wall 41 is for absorbing pressure generated at the time of ink droplet ejection toward the side opposite to the nozzle opening 11, and is unnecessary for the other pressure generating chambers 12 via the common ink chamber 31. Prevents positive or negative pressure from being applied.
In the present embodiment, the ink chamber side plate 40 is made 0.2 mm in consideration of rigidity required at the time of connection between the ink introduction port 42 and an external ink supply means, and a part of the thickness is 0.02 mm.
The thickness of the ink chamber side plate 40 may be 0.02 mm from the beginning in order to omit the formation of the thin wall 41 by half etching.

On the other hand, on the elastic film 50 on the side opposite to the opening surface of the flow path forming substrate 10, a thickness of, for example, about 0.5 μm
A lower electrode film 60, a piezoelectric film 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 formed by lamination in a process to be described later. (Piezoelectric element). Thus, the elastic film 50
In the region facing each pressure generating chamber 12, a piezoelectric vibrator is provided independently for each pressure generating chamber 12, and in the present embodiment, the lower electrode film 60 is a common electrode of the piezoelectric vibrator.
Although the upper electrode film 80 is used as an individual electrode of the piezoelectric vibrator, there is no problem even if the upper electrode film 80 is reversed for convenience of a drive circuit and wiring. In the present embodiment, the piezoelectric film 70 is connected to each pressure generating chamber 12.
However, the piezoelectric film may be provided as a whole, and the upper electrode film 80 may be separately provided so as to correspond to each pressure generating chamber 12. In any case, each pressure generating chamber 1
That is, a piezoelectric active portion is formed every two.

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 silicon single crystal substrate wafer 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 to be described later, which is formed by sputtering or a sol-gel method, has a thickness of 600 to 100
This is because it is necessary to perform crystallization by firing at a temperature of about 0 ° C. That is, the material of the lower electrode film 70 must be able to maintain conductivity at such a high temperature and in an oxidizing atmosphere. In particular, when PZT is used as 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 sputtering, but in this embodiment, a so-called sol in which a metal organic substance is dissolved and dispersed in a solvent is applied, dried and gelled, and further baked at a high temperature. A so-called sol-gel method for obtaining a piezoelectric film 70 made of an 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.
The piezoelectric film 70 and the upper electrode film 80 are patterned.

First, as shown in FIG. 4A, the lower electrode film 60, the piezoelectric film 70, and the upper electrode film 80 are etched together to pattern the entire pattern of the lower electrode film 60. Next, as shown in FIG. 4B, only the piezoelectric film 70 and the upper electrode film 80 are etched to
0 patterning is performed. Next, as shown in FIG. 4C, the piezoelectric active region is a region opposed to both sides in the width direction of each pressure generating chamber 12 (in FIG. 4, the pressure generating chamber 12 is before being formed, but is indicated by a broken line). By removing portions of the lower electrode film 60 corresponding to the arms of the diaphragm on both sides of the portion 320, a lower electrode film removing portion 350 is formed. Thus, the lower electrode film removing section 3
By providing 50, the amount of displacement due to application of a voltage to the piezoelectric body active section 320 is improved.

In the present embodiment, the lower electrode removing section 35
Although 0 is formed by completely removing the lower electrode film 60, a part of the lower electrode film 60 may be removed by half etching or the like to form a thin film. In this case, the lower electrode film 60 may serve as an elastic body and a lower electrode without the elastic film 50.

As described above, after patterning the lower electrode film 60 and the like, preferably, at least the periphery of the upper surface of each upper electrode film 80, and the piezoelectric film 70 and the lower electrode film 60 are preferably formed.
Is formed so as to cover the side surfaces of the substrate (see FIG. 1).

The respective piezoelectric active portions 3 of the insulator layer 90
A contact hole 91 that exposes a part of the upper electrode film 80 is formed in a part of the part that covers the upper surface of the part corresponding to one end of 20 to connect to a lead electrode 100 described later. One end is connected to each upper electrode film 80 via the contact hole 91, and the other end is formed with a lead electrode 100 extending to the connection terminal portion. The lead electrode 100 is formed so as to be as narrow as possible so as to reliably supply a drive signal to the upper electrode film 80.
In the present embodiment, the contact hole 91 is provided at a position facing the peripheral wall of the pressure generating chamber 12,
It may be provided at a position facing the pressure generating chamber 12.

FIG. 5 shows a process for forming such an insulator layer.
Shown in

First, as shown in FIG. 5A, an insulator layer 90 is formed so as to cover the periphery of the upper electrode film 80, the side surfaces of the piezoelectric film 70 and the lower electrode film 60. In the present embodiment, a negative photosensitive polyimide is used as the insulator layer 90.

Next, as shown in FIG. 5B, by patterning the insulator layer 90, each piezoelectric active portion 32 is patterned.
A contact hole 91 is formed in a portion corresponding to the vicinity of the end of 0. Subsequently, a lead electrode 100 connected to the upper electrode film 80 via the contact hole 91 is formed by patterning after forming a conductor such as Cr-Au over the entire surface. FIG. 5B shows a cross section of the contact hole 91 in a region facing the peripheral wall outside the pressure generating chamber 12 for convenience of explanation.

The above is the film forming process. After forming the film in this manner, as shown in FIG. 5C, the silicon single crystal substrate is anisotropically etched 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 the process is completed, the flow path forming substrate 10 having one chip size as shown in FIG. To divide. Further, the divided flow path forming substrate 10 is sequentially adhered and integrated with the sealing plate 20, the common ink chamber forming substrate 30, and the ink chamber side plate 40 to form an ink jet recording head.

The ink jet head thus configured takes in ink from an ink inlet 42 connected to external ink supply means (not shown), fills the interior from the common ink chamber 31 to the nozzle opening 11 with ink,
In accordance with a recording signal from an external drive circuit (not shown), a voltage is applied between the lower electrode film 60 and the upper electrode film 80 via the lead electrode 100, and the elastic film 50, the lower electrode film 60, and the piezoelectric film 70 The pressure generating chamber 1 is deformed by bending.
The pressure in 2 increases, and ink droplets are ejected from nozzle opening 11.

The piezoelectric active portion 320 thus formed
FIG. 6 shows a planar positional relationship between the pressure generating chamber 12 and the pressure generating chamber 12.

As shown in FIG. 6, the piezoelectric active portion 320 composed of the piezoelectric film 70 and the upper electrode film 80 is basically provided in a region facing the pressure generating chamber 12. At one end of the tube 12, it extends from a region facing the pressure generating chamber 12 to a region facing the peripheral wall. A wide portion 320a having a large width is formed at an end of a portion extending to a region facing the peripheral wall. A long contact hole 91 is formed in the insulator layer 90 covering the wide portion 320a along the width direction, and the upper electrode film 80 and the lead electrode 100 are connected via the contact hole 91. I have.

In such a configuration, when a current flows from the lead electrode 100 to the upper electrode film 80 through the contact hole 91, the current flows along the longitudinal direction of the piezoelectric active portion 320, that is, in the longitudinal direction of the contact hole 91. Outflow from a direction perpendicular to Therefore, the current density e at that time is dispersed in the longitudinal direction of the contact hole 91,
Destruction near the contact hole 91 due to an overcurrent is prevented.

The lead electrode 100 is formed on the upper electrode film 80.
Since the resistance is remarkably small in comparison with the above, the distribution of the current density is determined by the direction of the flow from the contact hole 91 to the upper electrode film 80. As shown in FIG. 7A, when the narrow portion 80a is formed in the upper electrode film 80, from the contact hole 91A toward the narrow portion 80a, that is, along the arrow B in the figure. Since a current flows, the contact hole 91A is formed to be elongated along a direction orthogonal to the direction. Therefore, also in this case, since the current density e is distributed along the longitudinal direction of the contact hole 91A, breakage due to overcurrent is prevented.

The direction in which the current flows and the direction in which the contact holes extend need not necessarily be orthogonal to each other. For example, as shown in FIG. The contact hole 91B may be elongated in the direction intersecting.

Further, as shown in FIG. 7C, a contact hole 91C may be provided in the center of the pressure generating chamber 12. In this case, the current flows through the contact hole 91C.
Current flows into the entire surroundings from above, the current density is dispersed, and destruction due to overcurrent is prevented.

(Embodiment 2) FIG. 8 shows a pattern shape of a piezoelectric active portion and the like near a pressure generating chamber of an ink jet recording head according to Embodiment 2 of the present invention.

In this embodiment, a fan-shaped wide portion 320b is formed at the end of the piezoelectric active portion 320 extending to the region facing the peripheral wall of the pressure generating chamber 12, and extends along the end of the wide portion 320b. In the present embodiment, a plurality of contact holes 92 are formed.

In such a structure, since the plurality of contact holes 92 are arranged in a direction substantially perpendicular to the direction in which the current flows from the lead electrode 100, the flow of the current into and out of the contact holes 92 is substantially uniform. It is dispersed and destruction by overcurrent or the like is prevented.

(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 addition to the above-described sealing plate 20, the common ink chamber forming plate 30 may be made of glass ceramic, and the thin film 41 may be made of glass ceramic as a separate member. Changes are free.

In the above-described embodiment, the nozzle openings are formed on the end surface of the flow path forming substrate 10. However, the nozzle openings may be formed to project in a direction perpendicular to the surface.

FIG. 9 is an exploded perspective view of the embodiment configured as described above, and FIG. 10 is a cross-sectional view of the flow path. In this embodiment, the nozzle opening 11 is formed in the nozzle substrate 120 opposite to the piezoelectric vibrator, and the nozzle communication port 22 that connects the nozzle opening 11 and the pressure generating chamber 12 is formed with the sealing plate 20 and the common ink. It is arranged so as to penetrate the chamber forming plate 30, the thin plate 41A and the ink chamber side plate 40A.

In this embodiment, the thin plate 41
A is basically the same as the above-described embodiment except that the ink chamber side plate 40A and the ink chamber side plate 40A are separate members, and the opening is formed in the ink chamber side plate 40. Is omitted.

In this embodiment, as in the above-described embodiments, the current density is dispersed by extending the contact holes in a direction intersecting the direction in which the current flows from the contact portion. And destruction due to overcurrent can be prevented.

Of course, the present invention can be similarly applied to an ink jet recording head of a type in which a common ink chamber is formed in a flow path forming substrate.

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 described as an example.
Of course, the present invention is not limited to this. For example, a piezoelectric film is formed by laminating substrates to form a pressure generating chamber, or a piezoelectric film is formed by attaching a green sheet or by screen printing, or a piezoelectric film formed by crystal growth. The present invention can be applied to ink jet recording heads having various structures, such as those that form a recording medium.

Further, in each of the above embodiments, the elastic film is provided separately from the lower electrode film as the vibration plate, but the lower electrode film may also serve as the elastic film.

Further, the example in which the insulator layer is provided between the piezoelectric vibrator and the lead electrode has been described. However, the present invention is not limited to this. The conductive film may be thermally welded, and the anisotropic conductive film may be connected to the lead electrode, or may be connected using various bonding techniques such as wire bonding.

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

[0072]

As described above, according to the present invention, by extending the contact hole in the direction intersecting the direction of the current flowing from the contact hole to the upper electrode, the current flows near the end of the contact hole. Since the concentration can be prevented, it is possible to prevent the contact hole from being broken due to the overcurrent or the dielectric breakdown due to the migration due to the overcurrent.

[Brief description of the drawings]

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

FIG. 2 is a plan view and a cross-sectional view of the inkjet recording head according to the first embodiment of the present invention, showing the same.

FIG. 3 is a view showing a thin film manufacturing process according to the first embodiment of the present invention.

FIG. 4 is a diagram showing a thin film manufacturing process according to the first embodiment of the present invention.

FIG. 5 is a diagram illustrating a thin film manufacturing process according to the first embodiment of the present invention.

FIG. 6 is a plan view illustrating a main part of the ink jet recording head according to the first embodiment of the present invention.

FIG. 7 is a plan view illustrating a main part of an ink jet recording head according to a modification of the first embodiment of the present invention.

FIG. 8 is a plan view showing a main part of an ink jet recording head according to Embodiment 2 of the present invention.

FIG. 9 is an exploded perspective view of an ink jet recording head according to another embodiment of the present invention.

FIG. 10 is a cross-sectional view illustrating an ink jet recording head according to another embodiment of the present invention.

[Explanation of symbols]

Reference Signs List 10 flow path forming substrate 11 nozzle opening 12 pressure generating chamber 50 elastic film 60 lower electrode film 70 piezoelectric film 80 upper electrode film 90 insulator layer 91, 91A, 91B, 91C, 92 contact hole 100 lead electrode 320 piezoelectric active part 320a, 320b Wide section

Claims (6)

[Claims] 1. A vibrating plate constituting a part of a pressure generating chamber communicating with a nozzle opening, at least an upper surface of which functions as a lower electrode, a piezoelectric layer formed on a surface of the vibrating plate, and a piezoelectric layer formed on the surface of the vibrating plate. A contact portion serving as a connecting portion between the lead electrode for applying a voltage to the piezoelectric active portion and a connecting portion between the piezoelectric active portion and a piezoelectric vibrator comprising a piezoelectric active portion comprising an upper electrode formed on the surface; Wherein the contact portion extends along a direction intersecting the direction of current flow from the contact portion to the upper electrode. Recording head. 2. The piezoelectric element according to claim 1, wherein an insulating layer is formed on an upper surface of the piezoelectric active portion, and the contact portion is formed in a contact hole formed in the insulating layer. Inkjet recording head. 3. An ink jet recording head according to claim 2, wherein said contact hole is a long and narrow hole in a direction intersecting a direction in which current flows from said contact hole. 4. The ink-jet apparatus according to claim 2, wherein the contact holes include a plurality of holes, and are provided side by side in a direction intersecting a current flowing direction from the contact holes. Type recording head. 5. The ink jet type according to claim 1, wherein a narrow portion having a width smaller than that of another portion is provided near the contact portion of the upper electrode. Recording head. 6. The pressure generating chamber according to claim 1, wherein the pressure generating chamber is formed on a silicon single crystal substrate by anisotropic etching, and each layer of the piezoelectric vibrator is formed by film formation and lithography. An ink jet recording head, characterized in that: