Patent ID: 7161284
Filing Date: 2007-01-09
Classification: C04B,H01L

Abstract:
1. A multilayered piezoelectric/electrostrictive device comprising: a ceramic substrate, a plurality of piezoelectric/electrostrictive portions comprising a piezoelectric/electrostrictive ceramic composition; and a plurality of electrodes electrically connected with the piezoelectric/electrostrictive portions; wherein the piezoelectric/electrostrictive portions and the electrodes are alternately layered on the substrate; wherein a lowermost one of the piezoelectric/electrostrictive portions positioned in a lowermost piezoelectric/electrostrictive layer adheres to the substrate directly or through a lowermost one of the electrodes positioned in a lowermost electrode layer; and wherein a ratio (α=A/B) of an average particle size (A) of the piezoelectric/electrostrictive ceramic of the piezoelectric/electrostrictive portion to a thickness (B) of the piezoelectric/electrostrictive portion is greater than 0.2 and not more than 0.4 in each of the piezoelectric/electrostrictive portions.