Patent ID: 8212451

Claim:
A multi-layer piezoelectric element comprising: a stack having a plurality of piezoelectric layers and a plurality of metal layers, the piezoelectric layers and the metal layers being stacked one on another; a pair of external electrodes formed on the side faces of the stack, wherein at least one of the plurality of metal layers is a stress relieving layer having a plurality of partial metal layers and voids, the partial metal layers are scattered between two piezoelectric layers sandwiching the stress relieving layer in the direction of stacking, and wherein a plurality of junction sections are formed between said two piezoelectric layers to join said two piezoelectric layers with each other, the junction sections being disposed on both sides of an imaginary straight line which is drawn so as to connect the center in the direction of width of one of the external electrodes and the center in the direction of width of the other of the external electrodes in a plane that includes the stress relieving layer and is perpendicular to the stacking direction.