Patent ID: 7503114

Claim:
A method for producing an ink jet head including, on an Si substrate having a face orientation {110}, a piezoelectric element for discharging an ink from a discharge port, a vibrating plate provided on said piezoelectric element and an ink flow path communicating with said discharge port so as to correspond to said piezoelectric element, a portion of the substrate corresponding to said piezoelectric element being formed with a space and a side wall of said space having a face orientation {111}, and the side wall of said space provided in the substrate being substantially perpendicular to a main surface of the substrate prior to formation of said space, the method comprising: a step of providing a selectively etchable sacrifice layer on said substrate in a manner that the sacrifice layer is formed in a parallelogram shape with an acute included angle of 70.5° (viewing from above) and longer sides and shorter sides of the parallelogram are arranged parallel to faces equivalent to {111}; a step of forming an etching-resistant etching stop layer so as to cover said sacrifice layer; a step of forming a film of said piezoelectric element on said etching stop layer; a step of providing a mold material corresponding to said ink flow path on said vibrating plate; a step of providing a wall material of said ink flow path so as to cover said mold material; a step of eliminating the portion of said substrate corresponding to said piezoelectric element by a crystal axis anisotropic etching until said sacrifice layer is removed from a rear side of said substrate so as to form a space on the substrate; and a step of eliminating said mold material thereby forming said ink flow path.