PZT thin film bulk acoustic wave resonators and filters

Thin Film Bulk Acoustic Wave Resonators (FBAR) using Lead Zirconate Titanate (PZT) thin films as the piezoelectric active layer are favourable for voltage controlled oscillators and wide band filters due to the large electro-mechanical coupling coefficient of PZT. This paper reports the fabrication process and results of PZT FBARs and filters. The temperature coefficient and bias voltage effect are also presented.