Patent ID: 7343679

Claim:
A manufacturing method for manufacturing a liquid ejection element substrate for a liquid ejection element for ejecting liquid through an ejection outlet, said liquid ejection element substrate having a front side and back side including an energy generating element for generating energy for ejecting the liquid and an electrode for supplying electric power to the energy generating element, said method comprising: a step of forming on the front side of said substrate an energy generating element and wiring electrically connecting with said energy generating element; a step of forming a recess in the form of a groove on said side of the substrate at a position where said wiring is formed; a step of forming an embedded electrode electrically connected with said wiring by filling electrode material in said recess; and a step of thinning said substrate at the back side of said substrate after formation of said embedded electrode to expose said embedded electrode at the back side of said substrate, thus providing an electrode exposed at the back side of said substrate.