Individual cavity resonators and acoustics of an electrical filter comprising individual cavity resonators acoustics

摘要

A single cavity acoustics resonator comprises: a first electrode; a second electrode; a third electrode, which is between the first electrode and the second electrode is arranged. The individual cavity acoustics resonator also contains: a first piezoelectric layer, which is arranged between the third electrode and the first electrode and a first c - axis with an orientation; and a second piezoelectric layer, which is arranged between the third electrode and the second electrode and a second c - axis with an orientation parallel to the first c - axis. An application of a time-variant electrical signal in the case of a drive frequency to either the third electrode or to the first and second electrode results in a resonance of the individual cavity acoustics resonator at twice a fundamental resonant frequency and a cancellation of substantially all of the mixed products of even order in the individual cavity resonator. An electric filter and a duplexer are also described.