Method of manufacturing wiring substrate, and liquid ejection head manufactured by same

Abstract

The method of manufacturing a wiring substrate includes the steps of: forming a photocatalyst containing layer which is made of a material containing a photocatalytic material, on a substrate made of an insulating material; forming a resin layer in regions other than wire regions on the photocatalyst containing layer; radiating ultraviolet light on the photocatalyst containing layer while the substrate provided with the resin layer and the photocatalyst containing layer is immersed in a solution containing at least a metal ion and a sacrificial reagent, in such a manner that metal is deposited on exposed regions of the photocatalyst containing layer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The nature of this invention, as well as other objects and benefits thereof, will be explained in the following with reference to the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures and wherein:

FIGS. 1A to 1F are illustrative diagrams showing a method of manufacturing a wiring substrate according to a first embodiment of the present invention;

FIG. 2 is a cross-sectional diagram of a wiring substrate manufactured according to an embodiment of the present invention;

FIG. 3 is a cross-sectional diagram showing another mode of a wiring substrate manufactured according to an embodiment of the present invention;

FIG. 4 is a cross-sectional diagram showing another mode of a wiring substrate manufactured according to an embodiment of the present invention;

FIG. 5 is a cross-sectional diagram showing a liquid ejection head according to an embodiment of the present invention;

FIGS. 6A to 6F are illustrative diagrams showing a first method of manufacturing a wiring substrate according to a second embodiment of the present invention;

FIG. 7 is an illustrative diagram showing the band structure of photocatalytic materials and the oxidation-reduction potential of water;

FIGS. 8A to 8F are illustrative diagrams showing a second method of manufacturing a wiring substrate according to the second embodiment of the present invention; and

FIGS. 9A to 9D are partial illustrative diagrams showing the second method of manufacturing a wiring substrate according to the second embodiment of the present invention.

Claims

1. A method of manufacturing a wiring substrate, the method including the steps of: forming a photocatalyst containing layer which is made of a material containing a photocatalytic material, on a substrate made of an insulating material;forming a resin layer in regions other than wire regions on the photocatalyst containing layer;radiating ultraviolet light on the photocatalyst containing layer while the substrate provided with the resin layer and the photocatalyst containing layer is immersed in a solution containing at least a metal ion and a sacrificial reagent, in such a manner that metal is deposited on exposed regions of the photocatalyst containing layer.

2. The method of manufacturing a wiring substrate as defined in claim 1, wherein: a heat radiation region is further formed on the photocatalyst containing layer; andthe resin layer is formed in regions other than the wire regions and the heat radiation region on the photocatalyst containing layer.

3. The method of manufacturing a wiring substrate as defined in claim 1, wherein the photocatalytic material has a conduction band of which a lower end is less than a reduction potential of the metal, and has a band gap not less than 3 eV and not greater than 6 eV.

4. The method of manufacturing a wiring substrate as defined in claim 1, wherein the photocatalytic material has a conduction band of which a lower end is less than a potential of a standard hydrogen electrode, and has a band gap not less than 3 eV and not greater than 6 eV.

5. The method of manufacturing a wiring substrate as defined in claim 3, wherein the photocatalytic material is insoluble in water when the ultraviolet light is radiated on the photocatalytic material.

6. The method of manufacturing a wiring substrate as defined in claim 4, wherein the photocatalytic material is insoluble in water when the ultraviolet light is radiated on the photocatalytic material.

7. The method of manufacturing a wiring substrate as defined in claim 3, wherein the photocatalytic material is one of TiO2, SrTiO3, KTaO3, KTaNbO3, ZrO2, and a complex compound containing at least one of TiO2, SrTiO3, KTaO3, KTaNbO3, and ZrO2.

8. The method of manufacturing a wiring substrate as defined in claim 4, wherein the photocatalytic material is one of TiO2, SrTiO3, KTaO3, KTaNbO3, ZrO2, and a complex compound containing at least one of TiO2, SrTiO3, KTaO3, KTaNbO3, and ZrO2.

9. The method of manufacturing a wiring substrate as defined in claim 1, wherein the ultraviolet light has a wavelength not less than 210 nm and not greater than 420 nm.

10. The method of manufacturing a wiring substrate as defined in claim 1, wherein the resin layer is manufactured by one of a photolithography method and an imprint method.

11. The method of manufacturing a wiring substrate as defined in claim 1, wherein the solution contains at least one of a copper ion, a silver ion, a gold ion, and a platinum ion.

12. A liquid ejection head having a wiring substrate manufactured by means of the method as defined in claim 1.