Patent ID: 8461941

Claim:
Bulk acoustic wave resonator with adjustable resonance frequency, comprising: a piezoelectric element having first and second electrodes; and a switching element forming an additional electrode having a first position and further having a second position wherein the additional electrode is selectively disposed on top of one of the first and second electrodes in order to increase a total thickness of the electrode resulting in a modification of the resonance frequency of the resonator between a first non-zero resonance frequency and a second, different, non-zero resonance frequency; wherein the switching element comprises at least one contact bar deformable between the first position in which the additional electrode is separated from said one of the first and second electrodes and the second position in which the additional electrode is applied against said one of the first and second electrodes; wherein the first and second positions are stable positions; and wherein the contact bar comprises bistable internal electrodes which maintain the contact bar in the second position in response to heat.