Akustische Filmvolumenresonator-Vorrichtungen (FBAR-Vorrichtungen) ohne Hohlraum

摘要

The decoupled stacked bulk acoustic resonator (DSBAR) device has a lower film bulk acoustic resonator (FBAR), an upper FBAR stacked on the lower FBAR, and an acoustic decoupler between the FBARs. Each of the FBARs has opposed planar electrodes and a layer of piezoelectric material between the electrodes. The acoustic decoupler has acoustic decoupling layers of acoustic decoupling materials having different acoustic impedances. The acoustic impedances and thicknesses of the acoustic decoupling layers determine the acoustic impedance of the acoustic decoupler, and, hence, the pass bandwidth of the DSBAR device. Process-compatible acoustic decoupling materials can then be used to make acoustic decouplers with acoustic impedances (and pass bandwidths) that are not otherwise obtainable due to the lack of process-compatible acoustic decoupling materials with such acoustic impedances.