Patent ID: 7524038

Claim:
A liquid-jet head comprising: a passage-forming substrate on which pressure generating chambers each communicating with a nozzle orifice are formed; piezoelectric element which is provided on one surface of the passage-forming substrate with a vibration plate interposed therebetween, and includes a lower electrode, a piezoelectric layer and an upper electrode; and a laminated electrode which includes layers different from layers forming any one of the lower electrode and the upper electrode, is provided on the vibration plate outward of regions corresponding to the pressure generating chambers, and is electrically connected to the lower electrode, wherein a stress relaxing layer is provided at least in regions corresponding to edge portions of the laminated electrode between the laminated electrode and the vibration plate, the stress relaxing layer being formed of a material having a linear expansion coefficient greater than that of the vibration plate and less than that of the laminated electrode.