JP2003011366A - Ink jet head and its manufacturing method and ink jet recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem that reliability of bonding is low. SOLUTION: A channel substrate 1 and an electrode substrate 2 are bonded through a polysilicon layer 25.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet head, a method of manufacturing the same, and an ink jet recording apparatus.

[0002]

2. Description of the Related Art In an ink jet recording apparatus used as an image recording apparatus or an image forming apparatus such as a printer, a facsimile, a copying machine or the like, a nozzle for ejecting an ink droplet and an ejection chamber (ink channel, ink chamber, Also referred to as a pressure chamber, a liquid chamber, a pressurizing chamber, a pressurizing liquid chamber, etc.), a vibrating plate forming the wall surface of the discharge chamber, and an electrode facing the vibrating plate. There is one equipped with an electrostatic ink jet head that ejects ink droplets from nozzles by deforming with electrostatic force to change the pressure / volume in the ejection chamber.

An ink jet head utilizing such electrostatic force ejects ink droplets from a nozzle by applying a voltage to a vibrating plate and an individual electrode facing the vibrating plate to deform the vibrating plate by the electrostatic force. Therefore, the mechanical deformation characteristics of the diaphragm greatly affect the ink ejection characteristics. Therefore, it is necessary to reduce the thickness of the diaphragm and control it with high accuracy.

Therefore, conventionally, a technique using an etching stop layer is effective for thinning the diaphragm and controlling the thickness with high accuracy, and a technique using a high-concentration boron layer as the etching stop layer is known. (For example, JP-A-6-71882, JP-A-6-23986, and JP-A-9-267479).

Further, it is necessary to control the distance between the vibrating plate and the electrode, that is, the gap dimension with extremely high precision, and it is indispensable to make such a joint in the manufacture of an ink jet head having a laminated structure of substrates. In particular, for bonding silicon wafers to each other, there is a direct bonding method which is generally used as a bonding method which is used for manufacturing SOI (silicon-on-insulator) wafers and can obtain a reliable and strong bonding force. Is possible. In general, direct bonding used for manufacturing SOI wafers is performed at a high temperature of 1100 to 1200 ° C., and high bonding reliability is obtained due to the effect of melting the silicon oxide film. Therefore, in the case where a high concentration boron layer is used as the etching stop layer,
Silicon wafers are bonded directly to each other at 1100 ° C
(Japanese Patent Application Laid-Open No. H6-23986, Japanese Patent Application Laid-Open No. 9-267479, etc.).

Furthermore, in order to suppress the generation of residual charges between the diaphragm used also as the common electrode and the counter electrode (individual electrode) and improve the reliability, for example, Japanese Patent Laid-Open No. 8-1
In the inkjet head described in Japanese Patent No. 18626,
A silicon oxide film is formed on the surface of each of the common electrode (vibration plate) and the individual electrode. By providing a silicon oxide film as an insulating film on the surface of each of the common electrode (vibration plate) and the individual electrode, it is possible to avoid the direct contact between the common electrode and the individual electrode when the inkjet head is driven. Since the electrodes come into contact with each other, each electrode is not deteriorated or damaged due to collision or repeated stress, so that the insulation resistance and durability of the head are improved, and a long-life inkjet head can be obtained.

[0007]

As described above, in order to prevent a short circuit between the common electrode (vibration plate) and the individual electrode when the ink jet head is driven, at least the common electrode (vibration plate) or the individual electrode is prevented. An insulating film (silicon oxide film) may be provided on either side, but since the common electrode (vibration plate) is repeatedly mechanically deformed, it is more likely to be deteriorated or damaged than the individual electrodes. Therefore, at least the common electrode (diaphragm)
It can be said that an insulating film (silicon oxide film) is preferably present on the surface of the.

However, in these cases, when the viewpoint is shifted to the bonding process, the silicon oxide films are bonded to each other. The effect of melting the silicon oxide films is indispensable for bonding the silicon oxide films to each other, and in order to obtain bonding reliability, it is necessary to bond the silicon oxide films at a higher temperature (1200 ° C. or higher) than the bonding between the silicon and the silicon oxide films. is there.

However, in the case where the heat resistance of the electrode substrate and the high-concentration boron layer are used for the diaphragm as described above, the redistribution of boron directly affects the thickness of the diaphragm and its variation, and Quartz does not have heat resistance in a furnace tube used for bonding, and therefore a tube having good heat resistance such as SiC needs to be used, which is also limited in terms of equipment.

Therefore, in the process of manufacturing an actuator or an electrostatic ink jet head in which an insulating film is attached to at least the common electrode (vibration plate) as described above, it is an important technical subject to lower the bonding temperature. Becomes

The present invention has been made in view of the above problems, and provides a highly reliable ink jet head by lowering the bonding temperature, a method of manufacturing the same, and a highly reliable ink jet recording apparatus. The purpose is to

[0012]

In order to solve the above-mentioned problems, among the ink jet heads according to the present invention, the ink jet head according to claim 1 forms at least a discharge chamber and a vibration plate, and faces an electrode of the vibration plate. A first substrate having a protective insulating film on its surface and an engraved portion forming a gap between the electrode and the diaphragm and the electrode, and a polysilicon layer on at least a part of the bonding surface with the first substrate. The second substrate on which is formed is joined.

According to a second aspect of the present invention, in the ink jet head according to the first aspect, the surface of the polysilicon layer is polished. An inkjet head according to a third aspect is the inkjet head according to the first or second aspect, wherein the polysilicon layer contains boron. According to a fourth aspect of the present invention, in the inkjet head according to any of the first to third aspects, the protective insulating film is a thermal oxide film.

An ink jet head according to a fifth aspect is the ink jet head according to any one of the first to fourth aspects, in which an engraved portion is formed in the electrode. According to a sixth aspect of the present invention, in the ink jet head according to any of the first to fourth aspects, a protective insulating film is formed on a surface of the electrode. According to a seventh aspect of the present invention, there is provided the inkjet head according to any one of the first to fourth aspects, wherein a protective insulating film is formed on a surface of the electrode and a carved portion is formed on the protective insulating film.

An ink jet head according to an eighth aspect is the ink jet head according to any one of the first to seventh aspects, in which the electrodes are separated by a separation region and an insulating film is embedded therein. The ink jet head according to claim 9,
In the ink jet head according to claim 8, the insulating film filling the separation area between the electrodes is a silicon oxide film, and the protective insulating film formed on the electrode surface includes at least a silicon nitride film layer.

An ink jet head according to a tenth aspect is the ink jet head according to any one of the first to ninth aspects, wherein the electrode contains a high melting point metal or a high melting point metal silicide. The inkjet head according to claim 11,
The inkjet head according to any one of claims 1 to 10, wherein the diaphragm is formed of a high-concentration P-type impurity silicon layer.

The ink jet head according to claim 12 and the ink jet head according to any one of claims 1 to 11, further comprising an ink supply port penetrating both the first substrate and the second substrate, the second substrate Has a silicon oxide film layer containing boron and / or phosphorus formed on a part of the bonding surface around the ink supply port.

An ink jet head according to a thirteenth aspect is the ink jet head according to any one of the first to twelfth aspects, wherein the first substrate and the second substrate are directly bonded at 1000 ° C. or less.

The ink jet recording apparatus according to the present invention is
One of the inkjet heads according to the present invention is mounted.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings. First, a first embodiment of the present invention will be described with reference to FIGS. Note that FIG.
2 is an exploded perspective view of the inkjet head according to the same embodiment, FIG. 2 is a plan view of the head without a nozzle plate, FIG. 3 is a schematic cross-sectional view of the head along a longitudinal direction of a discharge chamber, and FIG. FIG. 3 is a schematic cross-sectional explanatory view taken along the lateral direction of the ejection chamber of the head.

This ink jet head is provided on the flow path substrate 1 which is the first substrate, the electrode substrate 2 which is the second substrate provided on the lower side of the flow path substrate 1, and the upper side of the flow path substrate 1. It is composed of a laminated structure in which a nozzle plate 3 which is a third substrate is laminated, and by these, the ejection chamber 6 which is an ink flow path through which the plurality of nozzles 4 communicate, and the ejection chamber 6 communicates with each other via a fluid resistance portion 7. The common liquid chamber 8 and the like are formed.

The flow path substrate 1 is formed of a single crystal silicon substrate having a (110) plane orientation, and forms a discharge chamber 6 and a diaphragm 10 that forms a wall surface serving as the bottom of the discharge chamber 6 (the space between the recesses is the discharge space). It forms a partition wall of the chamber 6), and a recess forming the common liquid chamber 8 is formed. Electrode substrate 2 of this flow path substrate 1
A protective insulating film 11 such as SiO ₂ having a thickness of 0.1 μm is formed by thermal oxidation on the surface on the side in order to prevent a dielectric breakdown or a short circuit between the vibration plate 10 and an electrode 15 described later during driving. .

In this channel substrate 1, for example, a high-concentration boron diffusion layer (boron-doped layer) as a high-concentration p-type impurity diffusion layer having a diaphragm thickness is formed on a single crystal silicon substrate,
When the discharge chamber 6, the common liquid chamber 8 and the like are formed by alkali anisotropic etching, the diaphragm 10 is desired to be formed by using a so-called etch stop technique in which the etching rate becomes extremely small when the boron-doped layer is exposed. It was manufactured to the plate thickness of. Although boron, gallium, aluminum, etc. are used as impurities forming the high-concentration p-type impurity layer, boron is generally used as an impurity forming the p-type impurity layer in the semiconductor field. And

The electrode substrate 2 is made of a silicon substrate having a thickness of 625 μm, and the thermal oxide film 12 has a thickness of 0.
6 μm thick, and the vibration plate 1 is formed on the thermal oxide film 12.
0, an insulating film 17 made of a silicon oxide film is formed on the individual electrode 15 and the individual electrode 15.
7 is provided with a recess 14 which will form a gap 16. The electrode 15 and the vibrating plate 10 constitute an electrostatic actuator (pressure generating means) that displaces the vibrating plate 10 to change the internal volume of the discharge chamber 6.

Then, on the insulating film 17, a polysilicon film 25 is formed on the surface to be joined to the flow path substrate 1.
That is, by providing the polysilicon film 25 on the bonding surface so as not to bond the silicon oxide films which are difficult to bond to each other, the bonding is made to be “silicon oxide film (corresponding to the insulating film 11 here) and polysilicon”. By "joining", it is possible to perform direct bonding with high bonding reliability at low temperature as compared with bonding between silicon oxide films.

The polysilicon film 25 is formed by AFM immediately after the film formation.
Surface roughness: Ra value of 3 to 4n
Although it was about m, the Ra value becomes 0.15 to 0.25 nm by polishing the surface, and a very good surface property capable of direct bonding can be obtained. By including boron in the polysilicon film, boron is diffused into the silicon oxide film at the time of bonding and the melting point of the silicon oxide film near the bonding interface is lowered, so that the temperature of the bonding can be further lowered and the reliability can be improved.

Therefore, as described above, the flow path substrate 1 and the electrode substrate 2 are bonded by the process of direct bonding via the insulating film 11 which is a silicon oxide film and the polysilicon film 25. The length of the gap 16 after the flow path substrate 1 and the electrode substrate 2 are joined (the distance between the diaphragm 10 and the electrode 15)
Is 0.25 μm.

The nozzle plate 3 is made of, for example, glass or plastic, metal such as stainless steel or Kovar (Fe29-Ni-17Co), or thin plate such as silicon. The nozzle plate 3 has nozzles corresponding to the number of the discharge chambers 6 at positions corresponding to the discharge chambers 6. 4 are formed.
Further, the fluid resistance portion 7 is formed so that the discharge chamber 6 of the flow path substrate 1 and the common liquid chamber 8 communicate with each other.

A common electrode 12 is provided on the flow path substrate 1. The common electrode 12 is attached by sputtering a metal such as Al and sintering (thermally diffusing) it to ensure electrical continuity with the flow path substrate 1 and the ohmic contact with the flow path substrate 1 made of a semiconductor substrate. Making contact.
Then, for example, a lead wire is bonded to the electrode pad portion 15a communicating with the common electrode 12 and each individual electrode 15 to connect the driver 21.

Further, the electrode substrate 2 is formed with a through hole which serves as an ink supply port 19 for supplying ink to the common liquid chamber 8 of the flow path substrate 1. By connecting an ink supply pipe to the ink intake port 18 by adhesion, the common liquid chamber 8, the discharge chamber 6 and the like are filled with ink supplied from the ink tank (not shown) through the ink intake port 18. As the ink to be used, one prepared by dissolving or dispersing a surfactant such as ethylene glycol and a dye or a pigment in a main solvent such as water, alcohol or toluene is used. Hot melt ink can also be used if a heater is attached.

In the thus constructed ink jet head, the surface of the electrode 15 is charged to a positive potential by applying a positive voltage pulse to the individual electrode 15 by the driver 21, for example. Since the lower surface of the vibrating plate 10 facing the electrode 15 is charged to a negative potential, the vibrating plate 10 is attracted by the electrostatic force and bends in the direction in which the distance between the vibrating plate 10 and the individual electrodes 15 is narrowed. At this time, the vibration plate 10 bends, so that ink is supplied from the reservoir (common liquid chamber) 8 to the ejection chamber 6 via the orifice (fluid resistance portion) 7.

Therefore, by turning off the voltage pulse applied to the individual electrode 15 and discharging the accumulated charge, the deflected diaphragm 10 is restored to the original position as described above, Due to the restoration operation, the internal pressure of the ejection chamber 6 rapidly rises, and the ink droplets are ejected from the nozzle 4 toward the recording paper (not shown).

Next, the ink jet head according to the present invention.
FIG. 5 and the manufacturing process of the second embodiment of FIG.
This will be described with reference to FIG. First, referring to FIG.
The manufacturing process of the plate will be described. As shown in FIG.
First, silicon having a thickness of 625 μm (100) plane orientation
A thermal oxide film 32a having a thickness of 0.6 μm is formed on one side of the substrate 32.
And a polysilicon film to be an electrode later is formed on the entire surface by the CVD method.
Is deposited to a thickness of 300 nm, and phosphorus is deposited by diffusion (PH _ThreeAnd O
_TwoPSG is deposited using gas as a diffusion source, 950 ° C 60
Heat treatment for a minute, and then the PSG film is removed)
Forming a low resistance polysilicon layer 33 doped with
It

Although the deposition of phosphorus is used here for doping phosphorus, the polysilicon film may be doped by ion implantation or the like. Although N-type (phosphorus-doped) polysilicon is used as the electrode material here, a refractory metal such as tungsten, refractory silicide such as tungsten silicide, or a laminated body of these and polysilicon is used. As a result, the resistance can be further reduced.

Next, as shown in FIG. 3B, a polysilicon film 18 is formed on the polysilicon layer 33 by the CVD method.
20 nm is deposited, and boron is deposited on the polysilicon film 18 by 30 k.
Ion implantation is performed at eV and 1E16 (atoms / cm ² ). Here, by containing boron in the polysilicon film 25, boron is diffused into the silicon oxide film 11 of the first substrate at the time of subsequent bonding (heat treatment), and the melting point of the silicon oxide film near the bonding interface is lowered. Further, the temperature of the joint can be lowered and the reliability can be improved.

Regarding the ion implantation used here, the peak concentration or the vicinity of the peak concentration is located in the polysilicon film in consideration of the film loss due to polishing in the subsequent step.
It is desirable to set the injection conditions. Here, as a method of doping the polysilicon film 25 with boron,
It is also possible to use a so-called doped polysilicon in which boron is introduced during polysilicon film formation, a solid diffusion method, a coating diffusion method, or the like.

After that, the surface of the polysilicon film 25 is polished. This polishing uses CMP (chemical-mechanical-poli
shing) is a technique used for mirror polishing of silicon wafers and planarization of substrates in semiconductor processes. The surface of the polysilicon film 25 before polishing was evaluated for surface property using AFM, and the surface roughness: Ra value was 3 to 4 nm.
The surface roughness (Ra value) was 0.2 nm or less by this polishing process, which was about the same, and a very good surface property capable of direct bonding was obtained. The polishing reduced the thickness of the polysilicon film 25 by 70 nm. This variation in the film reduction amount can be suppressed to + -7 nm by optimizing the polishing conditions.

Thereafter, as shown in FIG. 6C, the engraved portion 14 for forming the gap is formed by etching the polysilicon film 25 and the polysilicon film 33. The engraved portion 36 is formed in such a manner that the resist shape is inclined by a photolithography technique using a mask having a gradation pattern, and etching is performed so that the resist shape is transferred using Ar gas or the like so that the shape is in a non-parallel state. Was formed as follows.

Next, as shown in FIG. 3B, the individual electrodes 15 are formed by separating the polysilicon film 25 and the polysilicon film 33 into individual electrodes by the well-known photolithography technique and dry etching technique. Then, the electrode substrate 2 was obtained.

Since the engraved portion 14 that forms the gap 16 is formed on the individual electrode 15 itself, the gap is formed in the conventional ink jet head (the engraved portion is formed on the insulating film and the electrode film is formed on the engraved portion). Therefore, the accuracy of the gap can be improved as compared with the variation of the gap being the sum of the variation of the engraving amount and the variation of the thickness of the electrode film. Although the number of steps is increased, the durability of the inkjet head can be further improved by providing a protective insulating film also on the individual electrode 15.

Next, referring to FIG. 6, from the diaphragm formation to the heading.
The process up to completion is explained. First, as shown in FIG.
, The thickness of 520 μm with (110) plane orientation
A coating diffusion method is used to diffuse boron to the i substrate 31.
It was B on the Si substrate 31 _TwoO_ThreeDispersed in an organic solvent
Pin coating and heat treatment (1125 ° C 40 minutes)
Boron is further diffused to form a high-concentration boron diffusion layer 31a.
To do. In addition to the present embodiment, the diffusion method is BBr._ThreeFor
Used gas phase diffusion method, ion implantation method, solid diffusion method, etc.
May be.

After that, the B ₂ O ₃ layer on the surface of the Si substrate 31 is removed by hydrofluoric acid. A compound layer of silicon and boron is formed under the B ₂ O ₃ layer, and when it is removed, it can be removed with hydrofluoric acid by oxidizing. However, even if the compound layer is oxidized and the compound layer is removed by hydrofluoric acid in this way, the silicon surface in which boron is diffused is roughened, so that it cannot be bonded by direct bonding performed later.

Therefore, the surface property that can be directly bonded by CMP polishing (Ra = 5 μm □ measurement using AFM)
0.15 nm or less) was obtained. The Si substrate 31 (high-concentration boron diffusion layer 31
Good surface property (Ra = 0.
Oxide film 11 having a thickness of 20 nm or less) was formed.

Here, the oxide film 11 functions as a protective insulating film of the vibration plate 10. By using a thermal oxide film for the protective insulating film as in this embodiment, the insulation resistance and the reliability (charge) are improved. Due to reduced traps and excellent moisture absorption resistance)
Can be improved. The oxide film 11, which is the protective insulating film of the diaphragm, may have a smaller film thickness when the protective insulating film is also formed on the electrode side. For example, when a silicon oxide film having a thickness of 100 nm or more is formed as protective insulation for electrodes, the oxide film 11 may have a thickness of 30 to 50 nm.

Then, as shown in FIG. 6B, the electrode substrate 2 and the first substrate (silicon substrate) 31 are bonded by the direct bonding method.

Specifically, after cleaning each of the substrates 2 and 31 using a substrate cleaning method known as RCA cleaning, sulfuric acid / hydrogen peroxide mixture (sulfuric acid and hydrogen peroxide solution are mixed at a volume ratio of 2: 1 and a temperature of 10) is used.
By washing at 0 ° C. or higher) and making the joint surface hydrophilic, a surface state that facilitates direct joining is obtained. Then, each substrate 2, 3
After drying No. 1, both substrates were superposed under reduced pressure (room temperature) and pressed under reduced pressure to complete prebonding.

The important point in prebonding is that the surface of the polysilicon film 25, which is the bonding surface of the second substrate (electrode substrate) 2, has good surface properties (Ra: 0.2 nm or less) as described above.
In addition, the surface of the oxide film 11, which is the bonding surface of the first substrate (silicon substrate) 31, also has good surface properties (Ra: 0.2 nm or less) as described above. If the surface properties of both substrates to be joined are not good, pre-bonding will not occur at room temperature, and reliable joining will not be possible.

Thereafter, the bonded wafers were heat-treated (900 ° C., 2 hours) in a nitrogen gas atmosphere to obtain a strong bond. The important point here is that the boron-containing polysilicon film 25 is formed on the bonding surface of the second substrate (electrode substrate) 2, so that the boron is converted into the silicon oxide film 1 at the time of bonding.
Since it diffuses to 1 and lowers the melting point of the silicon oxide film near the bonding interface, direct bonding with high bonding reliability is possible at a relatively low temperature.

Next, a substrate 31 having a thickness of 520 μm is formed to a thickness of 1.
10 to 30 wt% using a silicon nitride film patterned by photolithography technology and dry etching technology as a mask
Anisotropic etching is performed on the substrate 31 at a temperature of 80 to 90 ° C. with the potassium hydroxide aqueous solution.

This etching has a boron concentration of 1E20 /
When the depth reaches cm ³ , the etching stops (the etching rate extremely decreases), and the flow path substrate 1 having the diaphragm 10 made of the high-concentration boron-doped silicon layer 31a and the discharge chamber 6 is obtained. To be As described above, by using the etching stop technique using the high-concentration boron layer and performing the bonding at a temperature at which the re-diffusion of boron does not occur, the diaphragm 10 whose thickness is controlled with high precision is formed. You can

Finally, as shown in FIG. 3C, the ink jet head is formed by bonding the nozzle plate 3 in which the nozzles 4 and grooves serving as the fluid resistance portion 7 are formed on the flow path substrate 1 with an adhesive or the like. Is completed.

Next, an ink jet head according to a third embodiment of the present invention will be described together with its manufacturing process with reference to FIG. First, as shown in FIG. 3A, a thermal oxide film 32a having a thickness of 0.6 μm is formed on one side of a silicon substrate 32 having a thickness of 625 μm (100) plane, and a polysilicon film 33 is formed on the entire surface by a CVD method. Deposited 100 nm by
Phosphorus or arsenic is ion-implanted, and heat treatment for activation is performed. Next, the tungsten silicide film 34 is formed to a thickness of 200 nm.
It is deposited by the sputtering method. These polysilicon films 3
The individual electrode 15 is formed of a laminated film of the tungsten silicide film 34 and the tungsten silicide film 34 as described later.

Before the sputtering of the tungsten silicide film, the surface of the polysilicon film 33 is reverse-sputtered (etched) with Ar to be cleaned (removal of a natural oxide film or the like), so that the film adhesion is highly reliable. Therefore, it is preferable to use a multi-chamber sputtering apparatus to continuously clean the deposition surface and continuously perform the deposition.

Here, since the tungsten silicide film is formed to have a thickness of 200 nm, the sheet resistance of the individual electrode 15 will be 10Ω / □ or less later. Although polysilicon and tungsten silicide are used for the electrodes here, other refractory metals or a laminated structure of these metals may be used.

Subsequently, a high temperature (830 ° C.) thermal CV is applied to the surface of the tungsten silicide film 34 forming the individual electrode 15.
A silicon oxide film 17 is formed by D as a protective insulating film.

Further, the polysilicon film 25 is formed on the surface of the silicon oxide film 17 by the CVD method in the same manner as described above.
Is deposited to a thickness of 120 nm, and boron is deposited on the polysilicon film 25.
Ions are implanted at 0 keV and 1E16 (atoms / cm ² ) to polish the surface of the polysilicon film 25. Surface roughness of the surface of the polysilicon film 25: Ra value is 0.2 nm or less, and a very good surface property capable of direct bonding is obtained.

Next, as shown in FIG. 7B, the engraved portion 14 for forming the gap 16 is formed by etching the polysilicon film 25 and the silicon oxide film 17.
The engraved portion 14 is formed in such a manner that the resist shape is inclined by a photolithography technique using a mask having a gradation pattern, and etching is performed so that the resist shape is transferred using Ar gas or the like so that the shape is in a non-parallel state. Was formed as follows.

The gradation mask, the photolithography conditions, and the dry etching conditions are matched so as to form a desired gap shape in consideration of the etching rate ratio between the resist and the polysilicon film 25 and the silicon oxide film 17.

After that, the polysilicon film 25 is formed by the well-known photolithography technique and dry etching technique.
And the silicon oxide film 17 and the tungsten silicide film 3
4. The electrode substrate 2 having the individual electrodes 15 formed by separating the polysilicon film 32 was obtained. Then, in the same manner as described above, the flow path substrate 1 is formed and the nozzle plate 3 is joined to complete the ink jet head.

Next, an ink jet head according to the fourth embodiment of the present invention will be described with reference to FIG. 8 together with its manufacturing process. First, as shown in FIG. 3A, a thermal oxide film 32a having a thickness of 0.6 μm is formed on one side of a silicon substrate 32 having a thickness of 625 μm (100) plane, and a polysilicon film 33 is formed on the entire surface by a CVD method. Deposited 100 nm by
Phosphorus or arsenic is ion-implanted, and heat treatment for activation is performed. Next, the tungsten silicide film 34 is formed to a thickness of 200 nm.
It is deposited by the sputtering method. These polysilicon films 3
The individual electrode 15 is formed of a laminated film of the tungsten silicide film 34 and the tungsten silicide film 34 as described later.

Before the sputtering of the tungsten silicide film, the surface of the polysilicon film 33 is reverse-sputtered (etched) with Ar to be cleaned (removal of a natural oxide film or the like), so that the adhesion of the film is highly reliable. Therefore, it is preferable to use a multi-chamber sputtering apparatus to continuously clean the deposition surface and continuously perform the deposition.

Then, the tungsten silicide film 34 and the polysilicon film 33 are separated by the well-known photolithography technique and dry etching technique to form the individual electrodes 15. Here, the individual electrode 15 is formed so that the separation distance is 0.5 μm in order to facilitate the filling of the separation space.

Subsequently, a silicon oxide film 17 is deposited as a protective insulating film by high-temperature (830 ° C.) thermal CVD to fill the spaces between the separations 15a of the individual electrodes 15 with the silicon oxide film 17 and to form 200 nm on the surfaces of the individual electrodes 15. A silicon oxide film 17 having a thickness of 1 is formed. Silicon oxide film 1
The surface of 7 is recessed 17a due to the influence of the embedded shape during separation.
You can

Further, a polysilicon film 25 is formed on the surface of the silicon oxide film 17 by the CVD method as described above.
0 nm is deposited and boron is deposited on the polysilicon film 25 by 60 ke.
Ion implantation is performed with V, 1E16 (atoms / cm ² ). Here, it is preferable to set the implantation conditions so that the peak concentration or the vicinity of the peak concentration is located in the polysilicon film in consideration of the film loss during the polishing process of the polysilicon film 25 in the subsequent process.

Next, as shown in FIG. 7C, the surface of the polysilicon film 25 is subjected to CMP (chemical-mechanical-po).
lishing). By setting the polishing amount (removal allowance) to 150 nm, the concave portions generated due to the influence of the embedded shape during the separation disappear, and the polysilicon film 25 can be completely flattened.
Further, the surface roughness: Ra value of the surface of the polysilicon film 25 is 0.2 nm or less, and a very good surface property capable of direct bonding is obtained.

Thereafter, as shown in FIG. 6D, the engraved portion 14 for forming the gap is formed, and although not shown, the flow path substrate 1 is formed and the nozzle plate 3 is joined in the same manner as described above. The inkjet head is completed.

Next, an ink jet head according to the fifth embodiment of the present invention will be described with reference to FIG. 9 together with its manufacturing process. First, as shown in FIG. 3A, a thermal oxide film 32a having a thickness of 0.6 μm is formed on one side of a silicon substrate 32 having a thickness of 625 μm (100) plane, and a polysilicon film 33 is formed on the entire surface by a CVD method. Deposited 100 nm by
Phosphorus or arsenic is ion-implanted, and heat treatment for activation is performed. Next, the tungsten silicide film 34 is formed to a thickness of 200 nm.
It is deposited by the sputtering method. These polysilicon films 3
The individual electrode 15 is formed of a laminated film of the tungsten silicide film 34 and the tungsten silicide film 34 as described later.

Before the sputtering of the tungsten silicide film, the surface of the polysilicon film 33 is reverse-sputtered (etched) with Ar to be cleaned (removal of a natural oxide film or the like), so that the adhesion of the film is highly reliable. Therefore, it is preferable to use a multi-chamber sputtering apparatus to continuously clean the deposition surface and continuously perform the deposition.

Next, a 50 nm thick silicon nitride film 42 is formed on the tungsten silicide film 34 by LP-CVD.

Then, the tungsten silicide film 34, the polysilicon film 33, and the silicon nitride film 42 are separated by a well-known photolithography technique and dry etching technique to form the individual electrode 15 covered with the silicon nitride film 42. Here, the individual electrode 15 is formed so that the separation distance is 0.5 μm in order to facilitate the filling of the separation space.

Subsequently, a silicon oxide film 17 is deposited as a protective insulating film to a thickness of 400 nm by high temperature (830 ° C.) thermal CVD to fill the spaces between the separations 15a of the individual electrodes 15 with the silicon oxide film 17. .

After that, as shown in FIG. 9B, CMP (chemical-mechanical-po) is removed from the surface of the silicon oxide film 17.
lishing). Since the polishing rate of the silicon nitride film 42 is extremely lower than that of the silicon oxide film 17 (about 1/20), the silicon nitride film 42 serves as a CMP stopper.
Is very effective. As the polishing progresses, the planarization of the substrate progresses, and when the contact between the silicon nitride film 42, which is the polishing stopper, and the polishing pad becomes dominant, the torque of the carrier holding the substrate increases. By monitoring this torque, the end point of polishing can be detected, and the amount of polishing can be controlled with high accuracy. As a result, the gap can be formed with high accuracy.

Then, as shown in FIG.
Is high temperature (830 ℃) on the surface of silicon oxide film 17
The silicon oxide film 17 is deposited to a thickness of 20 nm by thermal CVD, and then the polysilicon film 25 is deposited to a thickness of 120 nm by a CVD method in the same manner as described above.
Boron at 30 keV, 1E16 (atoms / c
m ² ).

Then, as shown in FIG. 6C, polishing is performed from the surface of the polysilicon film 25 (polishing amount is about 50 nm).
And obtain good surface properties.

Thereafter, as shown in FIG. 7D, the engraved portion 14 for forming the gap is formed, and although not shown, the flow path substrate 1 is formed and the nozzle plate 3 is joined in the same manner as described above. The inkjet head is completed.

Next, an ink jet head according to a sixth embodiment of the present invention will be described with reference to FIG. 10 together with its manufacturing process. First, as shown in FIG. 3A, a thermal oxide film 32a having a thickness of 0.6 μm is formed on one side of a silicon substrate 32 having a thickness of 625 μm (100) plane, and a polysilicon film 33 is formed on the entire surface by a CVD method. Then, 100 nm is deposited, and phosphorus or arsenic is ion-implanted, and heat treatment for activation is performed. Next, the tungsten silicide film 34 is formed to 200
nm sputtering method. The individual electrode 15 is formed by a laminated film of the polysilicon film 33 and the tungsten silicide film 34 as described later.

Before the sputtering of the tungsten silicide film, the surface of the polysilicon film 33 is reverse-sputtered (etched) with Ar to be cleaned (removal of the natural oxide film, etc.), so that the adhesion of the film is highly reliable. Therefore, it is preferable to use a multi-chamber sputtering apparatus to continuously clean the deposition surface and continuously perform the deposition.

Next, a silicon nitride film 42 is formed to a thickness of 300 nm on the tungsten silicide film 34 by LP-CVD.

Then, the tungsten silicide film 34, the polysilicon film 33, and the silicon nitride film 42 are separated by a well-known photolithography technique and dry etching technique to form the individual electrode 15 covered with the silicon nitride film 42. Here, the individual electrode 15 is formed so that the separation distance is 0.5 μm in order to facilitate the filling of the separation space.

Subsequently, a silicon oxide film 17 as a protective insulating film is deposited to a thickness of 400 nm by high temperature (830 ° C.) thermal CVD to fill the spaces between the separations 15a of the individual electrodes 15 with the silicon oxide film 17. .

After that, as shown in FIG. 7B, the CMP (chemical-mechanical-po) is removed from the surface of the silicon oxide film 17.
lishing). Since the polishing rate of the silicon nitride film 42 is extremely lower than that of the silicon oxide film 17 (about 1/20), the silicon nitride film 42 serves as a CMP stopper.
Is very effective. As the polishing progresses, the planarization of the substrate progresses, and when the contact between the silicon nitride film 42, which is the polishing stopper, and the polishing pad becomes dominant, the torque of the carrier holding the substrate increases. The end point of polishing can be detected by monitoring this torque.

Then, as shown in FIG.
In the same manner as described above, the polysilicon film 25 is deposited to a thickness of 120 nm by the CVD method on the surface of the silicon oxide film 17 where
Ion implantation is performed at 16 (atoms / cm ² ), and polishing is performed from the surface of the polysilicon film 25 (polishing amount is about 50 nm).
And obtain good surface properties.

Thereafter, as shown in FIG. 7C, the engraved portion 14 for forming the gap is formed by etching the polysilicon film 25 and the silicon nitride film 42. The engraved portion 14 is formed in such a manner that the resist shape is inclined by a photolithography technique using a mask having a gradation pattern, and etching is performed so that the resist shape is transferred using Ar gas or the like so that the shape is in a non-parallel state. Was formed as follows. In this case, the silicon nitride film serves as a protective film insulating film of the electrode, and although the charge trap level is higher than that of the silicon oxide film formed by high temperature thermal CVD, it serves as a protective film having excellent moisture absorption resistance.

Although not shown, the ink jet head is completed by forming the flow path substrate 1 and joining the nozzle plate 3 in the same manner as described above.

Next, an ink jet head according to a seventh embodiment of the present invention will be described with reference to FIGS. 11 and 12. 11 is an exploded perspective view of the head, and FIG. 12 is a cross-sectional view of the head taken along the longitudinal direction of the diaphragm. In this inkjet head, a silicon oxide film 50 containing boron or both phosphorus and boron is formed on the bonding surface of the electrode substrate 2 with the flow path substrate 1 around the ink supply port 18. A polysilicon film 25 is formed on the other bonding surfaces.

At the time of bonding, the silicon oxide film layer 50 containing boron or both phosphorus and boron is melted, and the ink supply port 18 is formed.
The surrounding bonding can be made stronger, and even if the bonding interface is exposed to ink or the like, the ink liquid does not pass through the bonding interface, and the reliability of the inkjet head can be improved. In addition, a wet process using hydrofluoric acid, KOH, or the like can be used to form the ink supply port 18, and the process cost can be reduced.

The dummy electrode 5 is formed on the same plane as the electrode 15.
5 is formed. By providing the dummy electrode 55, the surface property of the silicon oxide film 17 can be improved.

Next, the manufacturing process of this ink jet head will be described with reference to FIGS. 13 and 14. As shown in (a1) of the figure, a thermal oxide film 32a having a thickness of 0.6 μm is formed on one side of a silicon substrate 32 having a thickness of 625 μm (100) and a polysilicon film is deposited to a thickness of 100 nm by a CVD method. Then, phosphorus or arsenic is ion-implanted and heat treatment for activation is performed. Next, a tungsten silicide film is deposited by the 200 nm sputtering method. In addition,
Before sputtering the tungsten silicide film, the surface of the polysilicon film is reverse-sputtered (etched) with Ar to be cleaned (removal of the natural oxide film, etc.), so that high reliability can be secured for the adhesion of the film. It is desirable to use a multi-chamber sputter device to continuously clean the deposit surface and deposit the deposit.

Then, the tungsten silicide film and the polysilicon film are patterned by the well-known photolithography technique and dry etching technique to form the individual electrode 15 composed of the tungsten silicide film and the polysilicon film, and they do not function as electrodes. A dummy electrode pattern 50 is formed. By forming the dummy electrode pattern 50 sparsely or densely, a step can be provided in the buried oxide film 17 later.

Here, the substrate is viewed from above (a2) in FIG.
As shown in FIG. 5, in the peripheral portion of the ink supply port portion 58 forming the ink supply port 18, the separation distance between the dummy electrode patterns 50 becomes long, that is, the dummy electrode pattern 5 is formed.
0 is formed sparsely.

Subsequently, a silicon oxide film 17 is deposited as a protective insulating film by high temperature (830 ° C.) thermal CVD to fill the spaces between the individual electrodes 15 with the silicon oxide film 17. At that time, the concave portion 5 is formed around the ink supply port 58.
You can do 9. Next, a polysilicon film 25 is deposited to a thickness of 120 nm on the silicon oxide film 17 by the CVD method, and boron is added to the polysilicon film 25 at 30 keV and 1E16 (atom).
ion implantation at s / cm ² ).

Next, as shown in FIG.
The upper polysilicon film 25 is removed by the well-known photolithography technique and dry etching technique.

Then, as shown in FIG.
A silicon oxide film 60 made of a film (silicon oxide film containing boron and phosphorus) is deposited to 400 nm by a CVD method. Here, the silicon oxide film 60 is made of BSG containing no phosphorus.
It may be a film. An important point of the present invention is to lower the melting point by including phosphorus or boron or both phosphorus and boron in the silicon oxide film.

Next, as shown in FIG. 14A, from the surface of the silicon oxide film 60, CMP (chemical-mechanical-po
lishing) to flatten the substrate. CMP here
Is a condition in which mechanical polishing is dominant (use a hard polishing cloth and use a polishing agent with a pH value close to neutral).
Thus, the polysilicon film 25 can be used as a polishing stopper.

After polishing, a silicon oxide film 60 is formed in the concave portion 59 in the peripheral portion of the ink supply port portion 58 on the joint surface, and a polysilicon film 25 is formed on the other joint surfaces. Further, the surfaces of the polysilicon film 25 and the silicon oxide film 60 after polishing have a surface property that allows good direct bonding.

Thereafter, as shown in FIG. 9B, the engraved portion 14 for forming the gap is formed, and the silicon substrate 31 to be the flow path substrate 1 is bonded in the same manner as described above. Then, as shown in FIG. 3C, the silicon substrate 32 is treated with a 25 wt% potassium hydroxide aqueous solution at a temperature of 90 ° C. using a silicon nitride film patterned by a photolithography technique or a dry etching technique as a mask.
Then, anisotropic etching is performed.

With this etching solution, the etching of the (100) plane proceeds at a rate of 2.5 μm / min. When the etching progresses and reaches the thermal oxide film 32a, the etching is stopped because the etching rate of the thermal oxide film is very small. Then, the thermal oxide film 32a, the silicon oxide film 17, the dummy electrode pattern 50, and the silicon oxide film 6 are formed using a hydrofluoric acid aqueous solution.
The opening 69 is formed by removing 0. Here, the dummy electrode pattern 50 is removed by lift-off by etching the silicon oxide film. Here, the polysilicon film 25 in the opening 69 could not be removed by lift-off and remained.

Then, in the same manner as described above, 10 to 30 wt
Of the diaphragm 10, the discharge chamber 6 and the common liquid chamber 8 are formed by anisotropically etching the silicon substrate 31 using an aqueous solution of potassium hydroxide (temperature: 80 to 90 ° C.). At this time, since the opening 69 is exposed to the potassium hydroxide aqueous solution, the high-concentration boron layer 31a and the silicon oxide film 1 in the opening are exposed.
1. The polysilicon film 25 is removed by etching, and the ink supply port 18 is formed.

Thereafter, although not shown, the nozzle plate 3 is joined to complete the ink jet head.

Next, an example of an ink jet recording apparatus equipped with an ink jet head according to the present invention is shown in FIG.
This will be described with reference to FIGS. 15 is a perspective explanatory view of the same recording apparatus, and FIG. 16 is a side view of a mechanical section of the same recording apparatus. This inkjet recording apparatus is composed of a carriage movable in the main scanning direction inside the recording apparatus main body 111, a recording head including the inkjet head according to the present invention mounted on the carriage, an ink cartridge for supplying ink to the recording head, and the like. Printing mechanism 1
A sheet feeding cassette (or a sheet feeding tray) 114 capable of accommodating a large number of sheets 113 from the front side can be detachably attached to the lower part of the apparatus main body 111 for accommodating 12 or the like. The manual feed tray 115 for manually feeding the paper 113 can be opened and closed, the paper 113 fed from the paper feed cassette 114 or the manual feed tray 115 is taken in, and a desired image is recorded by the printing mechanism unit 112. After that, the paper is discharged to the paper discharge tray 116 mounted on the rear surface side.

The printing mechanism section 112 slides the carriage 123 in the main scanning direction (the direction perpendicular to the paper surface in FIG. 16) by the main guide rod 12 and the sub guide rods 122, which are guide members which are horizontally mounted on the left and right side plates (not shown). The carriage 123 is freely held and has a plurality of ink ejection ports on which a head 124 is formed of an ink jet head that ejects ink droplets of yellow (Y), cyan (C), magenta (M), and black (Bk). They are arranged in a direction intersecting with the main scanning direction, and are mounted with the ink droplet ejection direction facing downward. Further, each ink cartridge 125 for supplying each color ink to the head 124 is replaceably mounted on the carriage 123.

The ink cartridge 125 has an upper atmosphere port communicating with the atmosphere, a lower supply port for supplying ink to the ink jet head, and a porous body filled with ink in the interior. The ink supplied to the inkjet head is maintained at a slight negative pressure by the capillary force of.

Although the heads 124 of the respective colors are used here as the recording head, a single head having nozzles for ejecting ink droplets of the respective colors may be used.

Here, the carriage 123 is slidably fitted to the main guide rod 112 on the rear side (downstream side in the sheet conveying direction) and slidably attached to the sub guide rod 122 on the front side (upstream side in the sheet conveying direction). It is placed in. Then, in order to move and scan the carriage 123 in the main scanning direction, a timing belt 130 is stretched between the drive pulley 128 and the driven pulley 129 which are rotationally driven by the main scanning motor 127, and the timing belt 130 is mounted on the carriage 123. The carriage 123 is reciprocally driven by the forward and reverse rotations of the main scanning motor 127.

On the other hand, in order to convey the paper 113 set in the paper feed cassette 114 to the lower side of the head 124, the paper feed roller 131 and the friction pad 132 for separating and feeding the paper 113 from the paper feed cassette 114, and the paper 11 are provided.
Guide member 133 for guiding the sheet 3 and the fed sheet 11
A conveyance roller 134 that reverses and conveys 3 is provided, a conveyance roller 135 that is pressed against the peripheral surface of the conveyance roller 134, and a leading end roller 136 that defines the feed angle of the paper 113 from the conveyance roller 134. Conveyor roller 1
The sub-scanning motor 137 is rotationally driven through a gear train.

A print receiving member 139, which is a paper guide member for guiding the paper 113 sent out from the carrying roller 134 below the recording head 124 in correspondence with the movement range of the carriage 123 in the main scanning direction, is provided. There is. A transport roller 141 and a spur 142 that are driven to rotate in order to send out the paper 113 in the paper discharge direction are provided on the downstream side of the print receiving member 139 in the paper transport direction, and further, the paper 113 is sent to the paper discharge tray 116. Roller 143 and spur 1
44, and guide members 145 and 146 that form the paper discharge path
And are arranged.

At the time of recording, by driving the recording head 124 in accordance with the image signal while moving the carriage 123, ink is ejected onto the stopped paper 113 to record one line, and the paper 113 is moved by a predetermined amount. After transportation, the next line is recorded. Upon receiving a recording end signal or a signal that the trailing edge of the paper 113 reaches the recording area, the recording operation is ended and the paper 113 is ejected.

A recovery device 147 for recovering the ejection failure of the head 124 is arranged at a position outside the recording area on the right end side of the carriage 123 in the moving direction. The recovery device 147 has a cap means, a suction means, and a cleaning means. The carriage 123 is moved to the recovery device 147 side while the printing is on standby, the head 124 is capped by the capping means, and the ejection port portion is kept wet to prevent ejection failure due to ink drying.
Also, by ejecting ink that is not related to recording during recording, etc., the ink viscosity of all ejection ports is made constant,
Maintains stable discharge performance.

When ejection failure occurs, the ejection port of the head 124 is sealed by a capping unit, and bubbles and the like are sucked out of the ejection port by the suction unit through the tube and ink and dust adhered to the ejection port surface. Is removed by the cleaning means and the ejection failure is recovered. Also,
The sucked ink is discharged to a waste ink reservoir (not shown) installed in the lower part of the main body, and absorbed and held by an ink absorber inside the waste ink reservoir.

In each of the above-mentioned embodiments, the present invention is mainly applied to the side shooter type ink jet head in which the displacement direction of the diaphragm and the ink droplet ejection direction are the same. It can be similarly applied to an inkjet head of an edge shooter system that is orthogonal to the droplet discharge direction.

[0111]

As described above, according to the ink jet head of claim 1 among the ink jet heads according to the present invention, the vibrating plate is provided on a part of the bonding surface with the first substrate provided with the protective insulating film. Since the second substrate on which the polysilicon layer is formed is joined, the protective insulating film and the polysilicon are joined together to enable direct joining with high joining reliability, and also joining of the silicon oxide films is performed. The bonding temperature can be lowered as compared with, and the bonding can be performed in a temperature range that does not affect the electrodes and the diaphragm, and the reliability is improved.

According to the ink jet head of the second aspect, since the surface of the polysilicon layer of the ink jet head of the first aspect is polished, the surface roughness can be reduced, and the direct bonding with high bonding reliability is achieved. It can be performed. According to the inkjet head of claim 3, since the polysilicon layer of the inkjet head of claim 1 or 2 contains boron, boron is diffused into the silicon oxide film of the first substrate at the time of bonding, and the boron near the bonding interface Since the melting point of the silicon oxide film is lowered, the joining reliability can be improved and the joining temperature can be lowered. According to the inkjet head of claim 4, since the protective insulating film of the inkjet head of any one of claims 1 to 3 is a thermal oxide film,
Insulation resistance and reliability can be improved.

According to the ink jet head of the fifth aspect, since the engraved portion is formed in the electrode of the ink jet head according to any of the first to fourth aspects, the accuracy of the gap can be improved. According to the ink jet head of the sixth aspect, since the protective insulating film is formed on the surface of the electrode of the ink jet head according to any of the first to fourth aspects, the durability of the head can be improved.

According to the ink jet head of claim 7, since the protective insulating film is formed on the surface of the electrode of the ink jet head according to any one of claims 1 to 4, and the engraved portion is formed in the protective insulating film, the engraving is performed. The controllability in forming the portions is improved, and the process yield can be improved.

According to the ink jet head of the eighth aspect, since the electrodes of the ink jet head according to any one of the first to seventh aspects are separated by the separation region and the insulating film is embedded, the ink is included in the head manufacturing process. The electrodes do not come into direct contact with the atmosphere, and there is no deterioration of the electrodes, so that the reliability can be improved.

According to the ink jet head of the ninth aspect, the insulating film filling the separation region between the electrodes of the ink jet head of the eighth aspect is a silicon oxide film, and the protective insulating film formed on the electrode surface is at least a silicon nitride film. Since a layer is included, a silicon oxide film and a silicon nitride film having a high polishing selection ratio can be used as a polishing stopper during the planarization process of a substrate using chemical mechanical polishing (CMP), and the thickness of the protective insulating film can be increased. The accuracy can be improved and the accuracy of the gap can be improved.

According to the ink jet head of the tenth aspect, since the electrode of the ink jet head according to any one of the first to ninth aspects contains the refractory metal or the refractory metal silicide, the electrode is prevented from being deteriorated during the thermal process. Since the wiring resistance of the electrodes can be reduced, the power consumption of the head can be reduced.

According to the ink jet head of the eleventh aspect, since the diaphragm of the ink jet head according to any one of the first to tenth aspects is formed of the high concentration P-type impurity silicon layer, the high concentration P-type impurity silicon layer is formed. It can be used as an etch stop layer for alkali anisotropic etching, and can form a diaphragm whose thickness is controlled with high precision.

According to the ink jet head of the twelfth aspect, the ink jet head according to any one of the first to eleventh aspects has an ink supply port penetrating both the first substrate and the second substrate, Since the silicon oxide film layer containing boron and / or phosphorus is formed on a part of the bonding surface around the ink supply port on the substrate, the silicon oxide film layer containing boron or both phosphorus and boron is melted at the time of bonding. By doing so, the bonding around the ink supply port can be made stronger, the ink liquid does not pass through the bonding interface even when the bonding interface is exposed to ink, etc., and the reliability can be improved and the ink supply can be improved. A wet process can be used for forming the mouth, and the process cost can be reduced.

According to the ink jet head of the thirteenth aspect, since the first substrate and the second substrate of the ink jet head according to any one of the first to twelfth aspects are directly bonded at 1000 ° C. or less, the heat resistance of the electrodes is high. Electrode failure due to
Bonding of wafers already formed with a high-concentration boron stop layer can also suppress changes in the boron concentration profile, and can form a vibration plate whose thickness is controlled with high precision.
The process yield can be improved.

According to the ink jet recording apparatus of the present invention, any one of the ink jet heads of the present invention is mounted, so that the ink ejection characteristics and durability are improved, and the image quality and reliability are improved.

[Brief description of drawings]

FIG. 1 is an exploded perspective view illustrating an inkjet head according to a first embodiment of the present invention.

FIG. 2 is an explanatory top view of the same head without a nozzle plate.

FIG. 3 is a schematic cross-sectional explanatory view along the long side direction of the ejection chamber of the same head.

FIG. 4 is a schematic cross-sectional explanatory view along the short side direction of the ejection chamber of the same head.

FIG. 5 is an explanatory view illustrating an inkjet head according to a second embodiment of the present invention together with its manufacturing process.

FIG. 6 is an explanatory view for explaining the same head together with its manufacturing process.

FIG. 7 is an explanatory diagram illustrating an inkjet head according to a third embodiment of the present invention together with its manufacturing process.

FIG. 8 is an explanatory diagram illustrating an inkjet head according to a fourth embodiment of the present invention together with its manufacturing process.

FIG. 9 is an explanatory diagram illustrating an inkjet head according to a fifth embodiment of the present invention together with its manufacturing process.

FIG. 10 is an explanatory diagram illustrating an inkjet head according to a sixth embodiment of the present invention together with its manufacturing process.

FIG. 11 is an exploded perspective view illustrating an inkjet head according to a seventh embodiment of the present invention.

FIG. 12 is an explanatory sectional view of the same head taken along the longitudinal direction of the diaphragm.

FIG. 13 is an explanatory diagram illustrating a manufacturing process of the head.

14 is an explanatory diagram illustrating a step following FIG.

FIG. 15 is an explanatory perspective view of an inkjet recording apparatus equipped with an inkjet head according to the present invention.

FIG. 16 is a side view for explaining a mechanism section of the recording apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Flow path substrate, 2 ... Electrode substrate, 3 ... Nozzle plate, 4 ... Nozzle, 6 ... Discharge chamber, 7 ... Fluid resistance part, 8 ... Common liquid chamber, 10
... diaphragm, 11 ... protective insulating film, 14 ... engraved part, 15
... electrode, 16 ... gap, 17 ... protective insulating film.

Claims (14)

[Claims] 1. A vibrating plate comprising: a nozzle for ejecting ink droplets; a discharge chamber communicating with the nozzle; a vibrating plate forming a wall surface of the ejecting chamber; and an electrode facing the vibrating plate. In an inkjet head that deforms by electrostatic force to eject ink droplets from the nozzles, at least the ejection chamber and the diaphragm are formed, and a first substrate having a protective insulating film on a surface facing the electrode of the diaphragm, The electrode and the engraved portion that forms the gap between the diaphragm and the electrode are formed, and the second substrate having the polysilicon layer formed on at least a part of the bonding surface with the first substrate is bonded Inkjet head characterized by being provided. 2. The inkjet head according to claim 1, wherein the surface of the polysilicon layer is polished. 3. The inkjet head according to claim 1, wherein the polysilicon layer contains boron. 4. The inkjet head according to claim 1, wherein the protective insulating film is a thermal oxide film. 5. The inkjet head according to claim 1, wherein the engraved portion is formed on the electrode. 6. The ink jet head according to claim 1, wherein a protective insulating film is formed on the surface of the electrode. 7. The ink jet head according to claim 1, wherein a protective insulating film is formed on a surface of the electrode, and the engraved portion is formed on the protective insulating film. Inkjet head. 8. The inkjet head according to any one of claims 1 to 7, wherein the electrodes are separated by a separation region and an insulating film is embedded therein. 9. The ink jet head according to claim 8, wherein the insulating film filling the separation region between the electrodes is a silicon oxide film, and the protective insulating film formed on the surface of the electrode includes at least a silicon nitride film layer. An inkjet head characterized in that. 10. The inkjet head according to claim 1, wherein the electrode contains a refractory metal or refractory metal silicide. 11. The ink jet head according to claim 1, wherein the vibrating plate has a high concentration P.
An ink jet head formed of a type impurity silicon layer. 12. The ink jet head according to claim 1, further comprising an ink supply port penetrating both the first substrate and the second substrate, the ink jet head being provided on the second substrate. The inkjet head is characterized in that a silicon oxide film layer containing boron and / or phosphorus is formed on a part of the bonding surface around the ink supply port. 13. The inkjet head according to claim 1, wherein the first substrate and the second substrate are directly bonded at 1000 ° C. or lower. 14. An inkjet recording apparatus equipped with an inkjet head, wherein the inkjet head is the inkjet head according to any one of claims 1 to 13.