Tunable FBARs: Intrinsic vs. extrinsic tunability.

The methods used to make the Film Bulk Acoustic Resonators (FBAR) tunable is reviewed. Intrinsically tunable FBARs make use ferroelectrics in ferroelectric and paraelectric (non-polar) phases have tunabilities up to 5% and more. Extrinsically tunable resonators are based on traditional piezoelectric FBARs and make use of external varactors and inductors. The low tunability (<2%) and low Q-factor (Q<100 due to tuning components) limits applications of these resonators. [ABSTRACT FROM PUBLISHER]