JP2001260355A - Ink jet head and method of manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the reliability of a head and to increase the yield of component by eliminating the need for bonding a cover plate. SOLUTION: A pressure generating mechanism having a nozzle opening and an ink chamber communicating with the nozzle opening and applying a pressure to ink in the chamber is provided on the other side of the nozzle opening through a thin film substrate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an ink jet head for performing image recording and the like by flying ink droplets onto a recording medium and a method of manufacturing the same.

[0002]

2. Description of the Related Art A main part of an ink jet head includes a nozzle opening for discharging ink, an ink chamber provided below the nozzle opening for applying pressure to the ink and discharging the ink, and an ink chamber. Is an ink pool that supplies ink to the ink pool. Further, an ink flow path is provided between the ink pool and the ink chamber.

An ink pressurizing mechanism is provided in the ink chamber, and between the pressurizing mechanism and the ink chamber is provided.
A lid plate for the ink chamber is interposed.

[0004] In the prior art, a single substrate in which a nozzle opening and an ink chamber are formed is disclosed in Japanese Patent Application Laid-Open No.
No. 5,798,811, and Japanese Patent Application Laid-Open No. Hei 4-312853. In each of these, a nozzle opening is provided on one surface of the crystal plate, and an ink chamber which is, for example, a tapered or bell-shaped space is provided below the nozzle opening. Also, JP-A-5-309835,
Japanese Patent Application Laid-Open No. 6-31914 discloses an ink jet printer in which an ink chamber, an ink pool, and an ink flow path are formed on a single substrate. In addition, Japanese Patent Application Laid-Open No. 6-21893
Japanese Patent Application Laid-Open No. 2000-139,087 discloses an ink chamber and a cover plate formed on a single substrate.

[0005]

As described above, in the prior art, the nozzle opening and the ink chamber are formed on one substrate, and thereafter, the ink pool and the ink supply path formed on another substrate are joined. Alternatively, the ink chamber, the ink pool and the ink flow path are formed on one substrate, and then the nozzles formed on another substrate are joined, or the ink chamber and the lid plate are formed on one substrate, After that, the nozzle opening formed on another substrate is joined.

For this reason, there arises a problem that peeling (peeling) occurs at the joint portion, and the airtightness of the space cannot be maintained. In addition, the accuracy and productivity of the head are reduced by the amount of the joining process.

The present invention has been made in such a background, and the reliability of the head is improved by providing the nozzle opening, the ink chamber, and the cover plate, which are the main parts constituting the ink jet head, on a single substrate. It is an object of the present invention to provide an ink jet head having improved productivity and component yield, and also having excellent productivity. SUMMARY OF THE INVENTION It is an object of the present invention to provide an ink jet head capable of avoiding charging of a nozzle opening due to static electricity.

[0008]

A first aspect of the present invention is an ink jet head. The general features of the structure of the present invention include a nozzle opening for discharging ink on a substrate, and a nozzle opening. An ink chamber that is formed in communication with the ink chamber and that applies pressure to the filled ink; a pressure generating mechanism that applies pressure to the ink in the ink chamber is provided on the other surface of the nozzle opening; The mechanism is provided via a thinned substrate.

That is, the ink jet head of the present invention is provided with a nozzle opening for ejecting ink to the substrate and an ink chamber formed in communication with the nozzle opening and for applying pressure to the filled ink. The thinned substrate is left on the other surface of the nozzle opening.

A nozzle opening is provided on one surface of the substrate in a vertical direction, and an ink chamber is provided in communication with the nozzle opening to apply pressure to the filled ink. The ink chamber is provided with respect to the nozzle opening. The cross section is formed in a tapered shape, and the bottom surface of the ink chamber is shaped to be covered with the thin plate remaining on the substrate.

More specifically, the silicon substrate [10]
A nozzle opening is provided in a direction perpendicular to the [0] plane, and an ink chamber formed in communication with the nozzle opening to apply pressure to the filled ink is provided as a wall surface including the [111] plane; The ink chamber is covered with the silicon substrate remaining on the other surface of the silicon substrate.

As a specific structure, a nozzle opening is formed in a vertical direction from one surface of the silicon substrate, and an ink chamber communicating with the nozzle opening and applying pressure to the filled ink is provided. The cross section is formed in a tapered shape toward the nozzle opening by etching, and the bottom surface of the ink chamber is covered with a thin film remaining after resisting the etching.

The thin film is formed by oxidizing silicon in the form of a slit or a high-concentration impurity diffusion layer having resistance to etching.

Alternatively, a polysilicon thin film is laminated on one surface of a silicon substrate, a nozzle opening is formed in a vertical direction from the other surface of the silicon substrate, and pressure is applied to the filled ink in communication with the nozzle opening. An ink chamber is provided, and a cross section of the ink chamber is formed in a tapered shape toward the nozzle opening by etching, and the bottom surface of the ink chamber is covered with a thin film remaining after the polysilicon thin film resists the etching.

Alternatively, a silicon film or a polysilicon thin film is laminated on one surface of a silicon substrate via a silicon oxide film, and a nozzle opening is formed vertically from the other surface of the silicon substrate, and communicates with the nozzle opening. An ink chamber is provided in which pressure is applied to the filled ink, the cross section of the ink chamber is formed in a tapered shape toward the nozzle opening by etching, and the bottom surface of the ink chamber is formed by the stacked silicon film or poly. The silicon thin film is covered by the thin film remaining after the etching.

It is desirable to provide an ink pool adjacent to the ink chamber through an ink supply hole for supplying ink to the ink chamber.

A second aspect of the present invention relates to a method for manufacturing an ink jet head.
Forming a high-concentration impurity diffusion layer on one surface of the silicon substrate, forming an etching-resistant mask film on the surface of the silicon substrate, and forming an opening for etching on a surface of the silicon substrate where an ink chamber is formed; , Forming the ink chamber by performing anisotropic etching from the one surface, and closing the opening of the formed ink chamber.

The step of providing an opening for forming the ink chamber is a step of providing a periodic groove, and the step of closing the opening of the ink chamber includes a step of oxidizing silicon remaining in the opening.

Alternatively, a step of forming a high concentration impurity diffusion layer on one surface of the silicon substrate, a step of forming an etching resistant mask film on the surface of the silicon substrate, and forming a nozzle opening from the other surface of the silicon substrate Forming an opening by dry etching to a depth substantially forming an ink chamber, and forming an ink chamber by performing anisotropic etching through the nozzle opening so that the high concentration impurity diffusion layer remains on the other surface. And a step of performing.

Alternatively, a step of laminating a polysilicon film on one surface of the silicon substrate, a step of forming a high-concentration impurity diffusion layer on the polysilicon film, and forming a nozzle opening from the other surface of the silicon substrate, Forming an opening by dry etching to a depth substantially forming an ink chamber; and performing anisotropic etching through the nozzle opening so that a high concentration impurity diffusion layer of the polysilicon film remains on the other surface. And forming a.

Alternatively, a step of laminating a silicon film or a polysilicon film on one surface of a silicon substrate via a silicon oxide film, and forming a high concentration impurity diffusion layer on the other surface of the silicon film or the polysilicon film and the other surface of the silicon substrate. Forming a nozzle opening from the other surface of the silicon substrate, and forming an opening by dry etching to a depth substantially forming an ink chamber; and forming the opening of the silicon film or the polysilicon film through the nozzle opening. Forming an ink chamber by performing anisotropic etching so that the high concentration impurity diffusion layer remains on one surface.

At this time, the surface of the silicon substrate is [10
[0] plane orientation, and the anisotropic etching is desirably performed so that the wall surface of the ink chamber becomes the [111] plane. Further, the high concentration impurity diffusion layer is preferably a high concentration boron diffusion layer.

As a result, it is possible to realize an ink jet head which does not require the joining of the cover plate and can improve the reliability of the head and the yield of parts. Further, when a conductor layer is formed of a high-concentration impurity diffusion layer at the nozzle opening, an effect of avoiding electrostatic charge due to friction caused by wiping or the like is produced.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIG. 1 is a schematic view showing the whole of an ink jet head, in which a thin film for transmitting pressure is removed from the ink jet head of the present invention. FIG. 5 is a view as seen from the side where the nozzle opening is provided (the surface side where the nozzle opening is not provided). That is, FIG. 2 is a view of the AA ′ section viewed from below. FIG. 4 is a cross-sectional view of the ink jet head according to the first embodiment of the present invention, and is a view showing a cross section taken along line CC ′ in FIG. A nozzle opening 100 is provided on the surface of the substrate and communicates with the chamber 101. The chamber 101 has four [111] planes 10
4 and has a square cross-sectional shape.

When the plane orientation of the substrate surface is (100),
The orientation of the plane constituting the [111] plane 104 is (-1-1-
1), (-1-11), (-111), (-11-1)
It is. When the plane orientation of the substrate surface is (010), [11
1] The orientation of the plane constituting the plane 104 is (−1-1-1),
(1-1-11), (1-11), and (1-1-1), and (-1-1) when the plane orientation of the substrate surface is (001).
-1), (1-1-1), (11-1), (-11-
1). [111] plane 1 constituting the chamber 101
Since 04 is very smooth, there is no problem with respect to bubble discharge property and ink stagnation in the chamber 101.

The chamber 101 is connected to an ink pool (not shown) by a supply hole (not shown). The thin film 105 is made of high-concentration boron-diffused Si and Si oxide or S
i-nitride. Since the thin film 105 can be formed without the need for bonding with an adhesive or the like, the number of steps can be reduced, and deterioration of air bubble discharge due to protrusion of the adhesive does not occur.

At a position of the chamber on the thin film 105, a pressure generating mechanism 107 wired (not shown) is disposed. Ink is supplied from an ink tank (not shown) to the ink pool. When a voltage was applied to the piezoelectric element 107 to cause the ink to fly, it was found that performance equivalent to that of the related art was obtained. In this embodiment, a piezoelectric element is used for the pressure generating mechanism. However, the same effect can be obtained by providing an ink heater on a thin film.

Next, a method of manufacturing the ink jet head of this embodiment will be described with reference to FIG. First, FIG.
As shown in FIG. 5A, a high-concentration boron diffusion layer 2 is provided on both sides of a Si wafer 1 having a [100] plane orientation (FIG. 5B). Here, the used Si wafer 1 has a thickness of 300 μm, and each of the high-concentration boron diffusion layers 2 has a thickness of 10 μm.

Next, as shown in FIG. 5C, the Si wafer 1 is thermally oxidized to form a silicon oxide film 3 having a thickness of 2 μm on the surface of the wafer as an etching resistant mask material. In this embodiment, a silicon oxide film is used as an etching resistant mask material, but the material is not limited to a silicon oxide film as long as the film can withstand a Si etchant, such as a silicon nitride film or a metal film. . This is the same in all the embodiments described below.

Next, a resist is applied to the Si wafer 1 and a resist mask pattern to be the nozzle opening 100 and the chamber 101 is formed at a predetermined position on the wafer surface by photolithography, and then oxidized by a buffered hydrofluoric acid solution. When the silicon film 3 is etched and the resist is removed, a pattern as shown in FIG. 5D is formed.
At this time, the pattern of the chamber 101 is a composite of a thin groove pattern having an inclination of 45 ° with respect to the orientation flat. The width of the pattern is 1 μm and the pitch is 11 μm. In addition, the shape of the narrow groove which is a pattern is such that the etching solution can enter from the groove and can be etched so as to hollow out the inside, and a beam of several μm order can be left.
The shape may be V-shaped instead of straight. Thereafter, an opening for forming the chamber 101 and a nozzle opening 100 are formed by Si dry etching (FIG. 5).
(E)).

Next, a chamber 101 is formed on the [111] crystal plane by Si anisotropic wet etching as shown in FIG. The etching is performed in ethylenediamine pyrocatechol water (EPW) heated to about 100 ° C. At the end of the anisotropic wet etching, beams having a width of 10 μm are arranged on the chamber 101 with a 1 μm gap therebetween.

Next, the silicon oxide film 3 is removed using a hydrofluoric acid solution (FIG. 5 (g)), and heated at 1100 ° C. for about 3 H in an atmosphere of H ₂ : O ₂ = 1: 1, and the Si wafer is heated. 1 is again thermally oxidized (FIG. 5 (h)). With this thermal oxidation, Si
Due to the thermal oxide film formed on the wafer, the chamber 10
The gap (1 μm) between the beams arranged on the top of the beam 1 is buried.

Finally, a piezoelectric element (not shown) is arranged and wired at a predetermined location, and connected to an ink tank (not shown) via a supply path (not shown) to complete an ink jet head.

(Second Embodiment) FIG. 6 is a sectional view of an ink jet head according to a second embodiment of the present invention.
It is a figure which shows the -C 'cross section. A nozzle opening 200 is provided on the substrate surface and communicates with the chamber 201. The chamber 201 is composed of four [111] planes 204, and has a square cross section.

When the plane orientation of the substrate surface is (100),
The orientation of the plane constituting the [111] plane 204 is (-1-1-
1), (-1-11), (-111), (-11-1)
It is. When the plane orientation of the substrate surface is (010), [11
1] The orientation of the plane constituting the plane 204 is (-1-1-1),
(1-1-11), (1-11), and (1-1-1), and (-1-1) when the plane orientation of the substrate surface is (001).
-1), (1-1-1), (11-1), (-11-
1). [111] plane 2 constituting the chamber 201
Since 04 is very smooth, there is no problem with respect to the bubble discharging property and ink stagnation in the chamber 201. The chamber 201 is connected to an ink pool (not shown) by a supply hole (not shown).

The high-concentration boron diffusion layer 202 provided as an etch stop layer is used as a thin film for transmitting pressure. Since a thin film can be formed without the need for bonding with an adhesive or the like, the number of steps can be reduced, and there is no deterioration in bubble discharge due to the protrusion of the adhesive.

At a position of the chamber on the high-concentration boron diffusion layer 202, a pressure generating mechanism 207 wired (not shown) is disposed. Ink is supplied from an ink tank (not shown) to the ink pool. When a voltage was applied to the pressure generating mechanism 207 to cause the ink to fly, it was found that performance equivalent to that of the related art could be obtained. In this embodiment, a piezoelectric element is used for the pressure generating mechanism. However, the same effect can be obtained by providing an ink heater on a thin film.

Next, a method of manufacturing the poly-Si diaphragm head shown in FIG. 7 will be described with reference to FIG. FIG. 8 shows a cross-sectional shape taken along the line CC ′ in FIG. First, polysilicon 311 is deposited on one surface of a Si wafer 1 having a [100] plane orientation as shown in FIG. 8A (FIG. 8B). Here, the used Si wafer 1 has a thickness of 300 μm, and the polysilicon 311 has a thickness of 15 μm.

Next, as shown in FIG.
The high concentration boron diffusion layers 2 and 312 are provided with a thickness of 10 μm on both surfaces. As shown in FIG. 8D, the Si wafer 1 is thermally oxidized, and a silicon oxide film 3 serving as an etching-resistant mask material is formed on the wafer surface with a thickness of 2 μm.

Next, a resist is applied to the Si wafer 1 and a resist mask pattern to be the nozzle opening 300 is formed at a predetermined position on the wafer surface by photolithography, and then the silicon oxide film 3 is buffered with a hydrofluoric acid solution. Is etched to remove the resist, FIG.
A pattern as shown in (e) is formed.

Thereafter, a nozzle opening 300 is formed by Si dry etching (FIG. 8F). At this time, in order to form the chamber 301 as shown in FIG. 8 (i), the dimensions must satisfy the following equation. The nozzle opening size is d, the dry etching opening depth (silicon oxide film /
When de is excluding the total thickness of the high-concentration boron diffusion layer), t is the substrate thickness, and b is the total thickness of the high-concentration boron diffusion layer, de + ／ · d · tan 54.7 ゜> t−b In the example, d = 30 μm and de = 270 μm.

Next, when Si anisotropic wet etching is performed using ethylenediamine pyrocatechol water (EPW) heated to about 100 ° C., as shown in FIG. Space is obtained. The bottom of this space reaches the polysilicon 311. Subsequently, when the anisotropic wet etching is performed, since the polysilicon 311 does not have a crystal orientation, etching that spreads in the lateral direction is performed. The protrusions appearing with this are selectively etched (FIG. 8 (h)), and finally a flat [111] plane without protrusions appears (FIG. 8 (h)).
(I)).

Finally, the silicon oxide film 3 is removed using a hydrofluoric acid solution (FIG. 8 (j)), and a piezoelectric element (not shown) is arranged at a predetermined place and wired, and a supply path (not shown) is provided. ) And an ink tank (not shown) to complete the ink jet head.

Next, a method of manufacturing the SOI head shown in FIG. 9 will be described with reference to FIG. FIG. 10 shows a cross section taken along the line CC ′ in FIG. First, the high-concentration boron diffusion layers 2 are provided on both sides of the SOI wafer 10 having the [100] plane orientation as shown in FIG. 10A (FIG. 10B). here,
One of the used SOI wafers 10 has a thickness of 300 μm (t
1) The other is 10 μm thick (t2) and 5 μm S
They are joined via an iO ₂ layer 412. Each of the high-concentration boron diffusion layers 2 has a thickness of 10 μm.

Next, as shown in FIG. 10C, a silicon nitride film 4 serving as an etching resistant mask material is formed on the entire surface of the SOI wafer 10 to a thickness of 0.5 μm. The SOI wafer 1
After applying a resist to the substrate 0 and forming a resist mask pattern to be a nozzle opening 400 at a predetermined position on the wafer surface by photolithography, the silicon nitride film 4 is etched by dry etching to remove the resist. A pattern as shown in (d) is formed.

Thereafter, a nozzle opening 400 is formed by Si dry etching (FIG. 10E). At this time, in order to form the chamber 401 as shown in FIG. 10 (i), the dimensions must satisfy the following equation. The nozzle opening dimension is d, the dry etch opening depth (excluding the total thickness of the silicon oxide film / high-concentration boron diffusion layer) is de, the substrate thickness on the side where the nozzle opening is formed is t1, and the side on which the nozzle opening is formed. When the thickness of the high-concentration boron diffusion layer provided on the substrate is b, de + ／ · d · tan 54.7 ゜> t1-b In this embodiment, d = 30 μm and de = 270 μm.

Next, ethylene dia heated to about 100 ° C.
Using Min Pyrocatechol Water (EPW)
When the Si anisotropic wet etching is performed, FIG.
As shown in the figure, a space surrounded by the [111] crystal plane is obtained.
You. The bottom of this space is SiO ₂Has reached layer 412
You. Change the etchant to hydrofluoric acid solution and etch
Is performed, SiO₂Layer 412 has a laterally extending edge.
Ching is performed (FIG. 10 (g)).

After etching to the chamber bottom area required by time management, the etching solution is again heated to about 100 ° C.
When the anisotropic wet etching is performed by changing to ethylenediamine pyrocatechol water (EPW) heated to a low temperature, the protrusions appearing due to the etching of the SiO ₂ layer 412 are selectively etched (FIG. 1
0 (h)), and finally a flat [111] plane without protrusions appears (FIG. 10 (i)).

Finally, the silicon nitride film 4 is removed using a phosphoric acid solution (FIG. 10 (j)), and a piezoelectric element (not shown)
Are arranged at predetermined locations and wired, and connected to an ink tank (not shown) via a supply path (not shown) to complete an ink jet head. In addition, the high-concentration boron diffusion layer 2 is conductive, and can avoid charging due to static electricity when wiping the nozzle opening 400 or the like.

[0050]

As described above, according to the present invention,
This eliminates the need for joining the cover plate, thereby improving the reliability of the head and the yield of parts. Electrostatic charging of the nozzle opening due to static electricity can be avoided.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing the overall configuration of an inkjet head according to an embodiment of the present invention.

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

FIG. 3 is a partially enlarged view of the inkjet head according to the embodiment of the present invention.

FIG. 4 is a sectional view of the inkjet head according to the first embodiment of the present invention.

FIG. 5 is a diagram for explaining a manufacturing process of the inkjet head according to the first embodiment of the present invention.

FIG. 6 is a sectional view of an inkjet head according to a second embodiment of the present invention.

FIG. 7 is a sectional view of a polysilicon diaphragm head according to an embodiment of the present invention.

FIG. 8 is a diagram for explaining a manufacturing process of the polysilicon diaphragm head according to the embodiment of the present invention.

FIG. 9 is a sectional view of an SOI head according to the embodiment of the present invention.

FIG. 10 is a diagram for explaining a manufacturing process of the SOI head according to the embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Si wafer 2, 102, 202, 402 High concentration boron diffusion layer 3 Silicon oxide film 4 Silicon nitride film 10 SIO wafer 100, 200, 300, 400 Nozzle opening 101, 201, 301, 401 Chamber 103 Oxide film 104, 204, 304, 404 [111] plane 105 Thin film 107, 207, 307, 407 Pressure generating mechanism 311 Polysilicon 312 High concentration boron diffusion layer (poly Si) 412 SiO ₂ layer

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yuji Akimoto 5-7-1 Shiba, Minato-ku, Tokyo Inside NEC Corporation (72) Inventor Torahiko Kanda 5-7-1 Shiba, Minato-ku, Tokyo Japan Inside Electric Co., Ltd. (72) Inventor Yasuhiro Otsuka 5-7-1 Shiba, Minato-ku, Tokyo NEC Corporation F-term (reference) 2C057 AF93 AG12 AG44 AP02 AP32 AP34 AP56 AP58 BA04 BA14

Claims (18)

[Claims] A substrate is provided with a nozzle opening for discharging ink and an ink chamber formed in communication with the nozzle opening to apply pressure to the filled ink. The ink jet head is characterized in that a pressure generating mechanism for providing pressure is provided on the other surface of the nozzle opening, and the pressure generating mechanism is provided via a thinned substrate. 2. A substrate, comprising: a nozzle opening from which ink is ejected; and an ink chamber formed in communication with the nozzle opening to apply pressure to the filled ink. An ink jet head, characterized in that a thinned substrate is left on the surface. 3. A nozzle opening is provided on one surface of the substrate in a vertical direction, and an ink chamber is provided in communication with the nozzle opening to apply pressure to the filled ink, and the ink chamber has a nozzle opening. The cross section is formed in a tapered shape with respect to the bottom surface of the ink chamber.
An ink jet head covered with a thin plate remaining on the substrate. 4. A nozzle opening is provided in a direction perpendicular to a [100] plane of a silicon substrate, and an ink chamber formed in communication with the nozzle opening and applying pressure to filled ink is [111]. An ink jet head provided as a wall surface including a surface, wherein the ink chamber is covered by a silicon substrate remaining on the other surface of the silicon substrate. 5. A nozzle opening is formed in a vertical direction from one surface of a silicon substrate, and an ink chamber is provided in communication with the nozzle opening to apply pressure to the filled ink, and a cross section of the ink chamber is formed by etching. An ink jet head formed in a tapered shape toward the nozzle opening, wherein the bottom surface of the ink chamber is covered with a thin film remaining after resisting etching. 6. The ink jet head according to claim 5, wherein the thin film is formed by oxidizing slit-like silicon. 7. The ink jet head according to claim 5, wherein said thin film is formed of a high-concentration impurity diffusion layer having resistance to etching. 8. A polysilicon thin film is laminated on one surface of a silicon substrate, a nozzle opening is formed vertically from the other surface of the silicon substrate, and pressure is applied to the filled ink in communication with the nozzle opening. An ink chamber is provided, a cross section of the ink chamber is formed in a tapered shape toward the nozzle opening by etching, and a bottom surface of the ink chamber is covered with a thin film in which the polysilicon thin film has resisted etching. An ink jet head, characterized in that: 9. A silicon film or a polysilicon thin film is laminated on one surface of a silicon substrate via a silicon oxide film, and a nozzle opening is formed in a vertical direction from the other surface of the silicon substrate, and communicates with the nozzle opening. An ink chamber for applying pressure to the filled ink, a cross section of the ink chamber is formed in a tapered shape toward the nozzle opening by etching, and a bottom surface of the ink chamber is formed by the laminated silicon film or poly. An ink jet head, wherein a silicon thin film is covered with a thin film remaining after etching. 10. The ink jet head according to claim 4, wherein an ink pool is provided adjacent to the ink chamber through an ink supply hole and supplies ink to the ink chamber. 11. A step of forming a high-concentration impurity diffusion layer on one surface of a silicon substrate, a step of forming an etching-resistant mask film on the surface of the silicon substrate, and a step of forming an ink chamber on one surface of the silicon substrate. An ink jet process comprising: providing an opening for etching; forming an ink chamber by performing anisotropic etching from the one surface; and closing the opening of the formed ink chamber. Head manufacturing method. 12. The method for manufacturing an ink jet head according to claim 11, wherein the step of providing an opening for forming an ink chamber is a step of providing a periodic groove. 13. The method according to claim 12, wherein the step of closing the opening of the ink chamber includes the step of oxidizing silicon remaining in the opening. 14. A step of forming a high-concentration impurity diffusion layer on one surface of a silicon substrate, a step of forming an etching-resistant mask film on the surface of the silicon substrate, and forming a nozzle opening from the other surface of the silicon substrate. Forming an opening by dry etching to a depth substantially forming an ink chamber; and forming an ink chamber by performing anisotropic etching through the nozzle opening so that the high concentration impurity diffusion layer remains on the other surface. A method of manufacturing an ink jet head. 15. A step of laminating a polysilicon film on one surface of a silicon substrate, a step of forming a high-concentration impurity diffusion layer on the polysilicon film, and forming a nozzle opening from the other surface of the silicon substrate. Forming an opening by dry etching to a depth substantially forming an ink chamber; and performing anisotropic etching through the nozzle opening so that a high concentration impurity diffusion layer of the polysilicon film remains on another surface. Forming an ink jet head. 16. A step of laminating a silicon film or a polysilicon film on one surface of a silicon substrate via a silicon oxide film, and forming a high-concentration impurity diffusion layer on the other surface of the silicon film or the polysilicon film and the other surface of the silicon substrate. Forming a nozzle opening from the other surface of the silicon substrate, and forming an opening by dry etching to a depth substantially forming an ink chamber; and forming the opening of the silicon film or the polysilicon film through the nozzle opening. Forming an ink chamber by performing anisotropic etching so that the high concentration impurity diffusion layer remains on one surface. 17. The silicon substrate surface has a [100] plane orientation, and the anisotropic etching is performed such that a wall surface of the ink chamber is a [111] plane.
7. The method for manufacturing an inkjet head according to any one of 6. 18. The method according to claim 11, wherein the high concentration impurity diffusion layer is a high concentration boron diffusion layer.