MANUFACTURING METHOD OF SUBSTRATE FOR INK JET HEAD AND MANUFACTURING METHOD OF INK JET RECORDING HEAD

Abstract

The present invention provides a manufacturing method of a substrate for an ink jet head including forming an ink supply opening to a silicon substrate, including (a) forming, at the back surface of the silicon substrate, an etching mask layer, which has an opening that is asymmetric with a center line, extending in the longitudinal direction, of an area on the surface of the silicon substrate where the ink supply opening is to be formed; (b) forming a non-through hole on the silicon substrate via the opening on the etching mask layer; and (c) forming the ink supply opening by performing a crystal anisotropic etching to the silicon substrate from the opening.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

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

FIG. 2 is a sectional view of a substrate for an ink jet head to which the manufacturing method according to one embodiment of the present invention is applied;

FIGS. 3A, 3B, 3C and 3D are views showing a manufacturing method of a substrate for an ink jet head according to one embodiment of the present invention;

FIGS. 4A, 4B and 4C are views showing a section of the various ink jet head substrates having plural ink supply openings formed thereon;

FIGS. 5A, 5B, 5C, 5D, 5E, 5F, 5G and 5H are views showing a manufacturing method of an ink jet recording head to which the manufacturing method of a substrate for an ink jet head shown in FIGS. 3A, 3B, 3C and 3D is applied.

FIG. 6 is a plan view showing a back surface of the substrate where a guide hole is formed at the process shown in FIG. 5F.

Claims

1. A manufacturing method of a substrate for an ink jet head including forming an ink supply opening to a silicon substrate, comprising: (a) forming, at a back surface of the silicon substrate, an etching mask layer, which has an opening that is asymmetric with a center line, extending in the longitudinal direction, of an area on a surface of the silicon substrate where the ink supply opening is to be formed;(b) forming a non-through hole on the silicon substrate via the opening on the etching mask layer; and(c) forming the ink supply opening by performing a crystal anisotropic etching to the silicon substrate from the opening.

2. A manufacturing method of a substrate for an ink jet head according to claim 1, wherein the step of (b) includes forming the plural non-through holes in at least two rows in the longitudinal direction of the opening of the etching mask layer.

3. A manufacturing method of a substrate for an ink jet head according to claim 1, wherein the step of (b) includes forming the plural non-through holes in at least two rows across the center line in the longitudinal direction of the opening of the etching mask layer, wherein the non-through holes are formed so as to satisfy the relationship of T−(X1−L)×tan 54.7°≧D1≧T−X1×tan 54.7°T−(X2−L)×tan 54.7°≧D2≧T−X2×tan 54.7°wherein the distance from the center line to the edge portion of the area where the ink supply opening is to be formed is defined as L, the thickness of the silicon substrate is defined as T, the distance from the center line to the center of the non-through hole at one row is defined as X1, the distance from the center line to the center of the non-through hole at the other row is defined as X2, the depth of the non-through hole at one row is defined as D1, and the depth of the non-through hole at the other row is defined as D2.

4. A manufacturing method of a substrate for an ink jet head according to claim 3, wherein the step of (b) includes forming the etching mask layer so as to satisfy the relationship of (T/tan 54.7°)+L>Y1>X1(T/tan 54.7°)+L>Y2>X2wherein the distance from the center line to the edge of the formed opening at the side where the non-through hole at one row is present is defined as Y1, and the distance from the center line to the edge of the formed opening at the side where the non-through hole at the other row is present is defined as Y2.

5. A manufacturing method of a substrate for an ink jet head according to claim 1, wherein the step of (b) includes forming the non-through hole by using fundamental harmonic, second harmonic, or third harmonic, of YAG.

6. A manufacturing method of a substrate for an ink jet head according to claim 1, comprising performing the crystal anisotropic etching to the silicon substrate by using TMAH solution.

7. A manufacturing method of a substrate for an ink jet head according to claim 1, wherein the crystal orientation surface of the front surface and back surface of the silicon substrate is (100).

8. A manufacturing method of a substrate for an ink jet head according to claim 1, wherein, at least at the stage before the step of (c), the sacrifice layer is formed at the portion on the surface of the silicon substrate where the ink supply opening is to be formed, in which the center line coincides with the center line extending in the longitudinal direction of the sacrifice layer and the edge portion of the sacrifice layer coincides with the edge portion of the area where the ink supply opening is to be formed, and at the step of (c), the crystal anisotropic etching is performed until the etched area of the silicon substrate reaches at least the sacrifice layer.

9. A manufacturing method of a substrate for an ink jet head according to claim 1, wherein, at least at the stage before the step of (c), a passivation layer having resistance to etching is formed on the surface of the silicon substrate, and a part of the passivation layer is removed so as to open the ink supply opening at the surface of the silicon substrate.

10. A manufacturing method of an ink jet head comprising: (a) forming a sacrifice layer at the portion on the silicon substrate where an ink supply opening is to be formed, the silicon substrate being provided with plural ink discharge energy generating elements that generate energy for discharging ink;(b) forming a passivation layer, having resistance to etching, on the surface of the silicon substrate so as to cover the sacrifice layer;(c) forming an etching mask layer, having an opening that is asymmetric with the center line of the sacrifice layer extending in the longitudinal direction of the sacrifice layer, on the back surface of the silicon substrate;(d) forming a mold material, which occupies the portion formed into the ink flow path, on the surface of the silicon substrate;(e) forming a nozzle forming member on the silicon substrate and mold material;(f) forming an ink discharge port to the nozzle forming member;(g) forming a non-through hole on the silicon substrate through the opening of the etching mask layer;(h) etching the silicon substrate with a crystal anisotropic etching until the etched area of the silicon substrate through the opening reaches at least the sacrifice layer;(i) removing a part of the passivation layer so as to open the ink supply opening on the surface of the silicon substrate; and(j) removing the mold material.

11. A manufacturing method of an ink jet head according to claim 10, wherein the step of (g) includes forming the plural non-through holes in at least two rows in the longitudinal direction of the opening of the etching mask layer.

12. A manufacturing method of an ink jet head according to claim 11, wherein the step of (g) includes forming the plural non-through holes in at least two rows across the center line, extending in the longitudinal direction, of the sacrifice layer in the longitudinal direction of the opening of the etching mask layer, wherein the non-through holes are formed so as to satisfy the relationship of T−(X1−L)×tan 54.7°≧D1≧T−X1×tan 54.7°T−(X2−L)×tan 54.7°≧D2≧T−X2×tan 54.7°in which the distance from the center line of the sacrifice layer extending in the longitudinal direction to the edge portion of the sacrifice layer is defined as L, the thickness of the silicon substrate is defined as T, the distance from the center line of the sacrifice layer extending in the longitudinal direction to the center of the non-through hole at one row is defined as X1, the distance from the center line of the sacrifice layer extending in the longitudinal direction to the center of the non-through hole at the other row is defined as X2, the depth of the non-through hole at one row is defined as D1, and the depth of the non-through hole at the other row is defined as D2.

13. A manufacturing method of an ink jet head according to claim 12, wherein the step of (c) includes forming the etching mask layer so as to satisfy the relationship of (T/tan 54.7°)+L>Y1>X1(T/tan 54.7°)+L>Y2>X2wherein the distance from the center line of the sacrifice layer extending in the longitudinal direction to the edge of the formed opening at the side where the non-through hole at one row is present is defined as Y1, and the distance from the center line of the sacrifice layer in the longitudinal direction to the edge of the formed opening at the side where the non-through hole at the other row is present is defined as Y2, the distance from the center line of the sacrifice layer extending in the longitudinal direction to the edge portion of the sacrifice layer is defined as L, and the thickness of the silicon substrate is defined as T.

14. An ink jet head comprising: a silicon substrate having formed thereon an energy generating element that generates energy for discharging ink, and an ink supply opening for supplying ink to the energy generating element; anda flow path forming member that forms an ink discharge port, and an ink flow path that communicates the ink discharge port with the ink supply opening;wherein the ink supply opening has two wall surfaces opposed to each other in a width direction of said ink supply opening, andsaid wall surfaces have a distance from a center line of said ink supply opening with respect to a back surface, which distance gradually becomes large to a certain depth position and which distance gradually becomes small toward the surface of said silicon substrate with the depth position defined as an apex where the distance becomes the greatest, and,of two wall surfaces of the ink supply opening, the depth position of the apex at one wall surface and the depth position of the apex at the other wall surface are different from each other.

15. An ink jet head according to claim 14, wherein the plural ink supply openings are formed on the silicon substrate.

16. An ink jet head according to claim 15, wherein, when the wall surface where the depth of the apex from the opening is deeper is defined as a first wall surface and the other wall surface is defined as a second wall surface, the first wall surface of one ink supply opening and the second wall surface of the other ink supply opening are included between the centers of two adjacent ink supply openings.

17. A manufacturing method of a substrate for an ink jet head including forming an ink supply opening on a silicon substrate, comprising: preparing a silicon substrate, wherein an etching mask layer having an opening, which is asymmetric with the center line, extending in the longitudinal direction, of an area on a surface of the silicon substrate where an ink supply opening is to be formed, is formed on a back surface of the silicon substrate, and a non-through hole is formed to the silicon substrate through the opening of the etching mask layer; andetching the silicon substrate by a crystal anisotropic etching to form the ink supply opening.