Patent ID: 7073265
Filing Date: 2006-07-11
Classification: H01L

Abstract:
1. A stacked piezoelectric device comprising piezoelectric layers composed of a piezoelectric material and internal electrode layers containing Cu, each of the piezoelectric layers being stacked alternately with each of the internal electrode layers, wherein the internal electrode layer contains not less than 50 percent by weight of Cu element, and wherein, between the internal electrode layer and the piezoelectric layer, there is a diffusion region formed by mutual diffusion of components of the internal electrode layer and the piezoelectric layer to the other layer and comprising at least one component of the piezoelectric material and Cu, wherein the diffusion region occupies not less than 90 percent of an area of the whole interface between the internal electrode layer and the piezoelectric layer, and a thickness of the diffusion region is not more than 10 percent of a thickness of the internal electrode layer.