Bulk acoustic resonator with matched resonance frequency and fabrication process

摘要

The resonator comprises a piezoelectric layer arranged between two electrodes. An electrical heating resistor is arranged in thermal contact with at least one of the electrodes. Temporary heating of the electrode enables the material constituting the electrode to be partially evaporated, so as to thin the electrode and thus adjust the resonance frequency. Measurement of the resonance frequency in the course of evaporation enables the heating to be interrupted when the required resonance frequency is obtained. One of the electrodes can be arranged on a substrate formed by an acoustic Bragg grating. The resonator can comprise a substrate comprising a cavity whereon one of the electrodes is at least partially arranged.