An Influence of an Electrode Configuration on Electrical Parameters of a Microelectronic Bulk Acoustic Wave Resonator with a Bragg Reflector

A microelectronic bulk acoustic wave (BAW) resonator based on piezoelectric AlN with an acoustic Bragg reflector of Mo and Al films are considered. The working frequency of the resonator prototype is $3.63\dots 3.78$ GHz and the quality factor is $270\dots 360$. The electromechanical coupling coefficient of the resonators is equal to $1.2\dots 1.5$ %. The effect of a configuration of upper electrode on electrical characteristics and equivalent electrical parameters of the resonator are studied. It is shown that with increasing the upper electrode area of the resonator the dynamic inductance decreases and the static capacitance, dynamic resistance and capacitance increase. It is shown to control the frequency parameters of BAW resonators various configurations of the upper electrode of the resonator can be used.