Patent ID: 8011761

Claim:
A liquid jet head comprising: a passage forming silicon substrate having a pressure generating chamber with a crystal face orientation of a surface being a (110) plane wherein the pressure generating chamber communicates with a liquid droplet ejecting nozzle; wherein the pressure generating chamber has a longitudinal direction and a width direction; and wherein the pressure generating chamber has a first (111) plane along the width direction and a second (111) plane along the longitudinal direction; an elastic film disposed above the pressure generating chamber; and a piezoelectric element having a lower electrode, a piezoelectric layer, and an upper electrode disposed above the elastic film; wherein both ends of the lower electrode and both ends of the upper electrode in the longitudinal direction are located in a region corresponding to the pressure generating chamber; and wherein one edge of the lower electrode and one edge of the upper electrode in the width direction are parallel to the first (111) plane of the pressure generating chamber.