Abstract: A Thin Film Bulk Acoustic Wave Resonator (FBAR), comprising a top electrode layer, a substrate, an acoustic mirror that is formed atop the substrate, and a piezoelectric layer that is formed between the top electrode layer and the acoustic mirror. The acoustic mirror is comprised of a plurality of stacked layers. One of the stacked layers forms a bottom electrode layer. At least another one of the stacked layers comprises a polymer material. The piezoelectric produces vibrations in response to a voltage being applied between the top electrode and the bottom electrode. The acoustic mirror acoustically isolates these vibrations from the substrate. The polymer material is preferably an electronic grade polymer and has a capability of withstanding a deposition of the piezoelectric layer at an elevated temperature. The layers forming the acoustic mirror which do not comprise the polymer material comprise a high acoustic impedance material such as, by example, tungsten (W).