Patent ID: 6975183
Filing Date: 2005-12-13
Classification: H03H,Y10T

Abstract:
1. A bulk acoustic wave resonator, comprising a first piezoelectric layer made of a material oriented toward a first direction; and a second piezoelectric layer made of a material oriented toward a second direction opposed to the first direction; the first piezoelectric layer and the second piezoelectric layer being acoustically coupled with each other; a first electrode, on which the first piezoelectric layer is at least partially formed; a second electrode formed at least partially on the first piezoelectric layer, the second piezoelectric layer being at least partially arranged on a first portion of the second electrode; an additional first piezoelectric layer arranged at least partially on a second portion of the second electrode, the second piezoelectric layer and the additional first piezoelectric layer being arranged so as to be spaced apart from each other; a third electrode arranged at least partially on the second piezoelectric layer; and a fourth electrode arranged at least partially on the additional first piezoelectric layer.