Patent ID: 8029685

Claim:
A method of manufacturing a liquid ejection head, wherein the liquid ejection head has liquid ejection openings, liquid paths communicating with the ejection openings and energy-generating elements that form heating portions to generate energy for discharging liquid, said method comprising: a step of forming porous silicon areas in portions where the liquid paths are to be formed, from one surface to inside of a silicon substrate; a step of forming a protective layer for protecting the heating portions at the porous silicon areas; a step of forming a layer member including the heating portions and an electrode layer for supplying electricity to the heating portions to heat them, on the protective layer; a step of forming the liquid ejection openings at a surface of the silicon substrate which is opposite to the one surface so that the liquid ejection openings communicate with the porous silicon areas; a step of forming a support substrate having a supply port for supplying the liquid to the liquid paths at a side of the silicon substrate having the layer member; a step of subsequently reducing a thickness of the silicon substrate formed with the porous silicon areas at the surface of the silicon substrate which is opposite the one surface; a step of communicating the supply port and the porous silicon area by passing through the protective layer; and a step of forming the liquid paths by removing the porous silicon areas.