Field-Controlled Ferroelectric Film Bulk Acoustic Wave Resonators and Filters

The exponential increase in the number of wireless devices as well as the limited wireless spectrum, poses significant challenges in the design of future wireless communication systems. Adaptive and reconfigurable radios that can change their frequency and mode of operation based on the unused/available wireless spectrum as well as their surrounding environmental conditions have been proposed to address such challenges. However, currently available RF and microwave circuit components cannot meet the performance requirements, and cost constraints necessary for the commercialization of such systems. This presentation is on the application of ferroelectric scandium aluminum nitride (ScAlN) and barium strontium titanate (BST) electric field controlled multilayer bulk acoustic wave resonators for the design of reconfigurable filters and filter banks. Various reconfigurable acoustic resonators and filters will be presented including recent results for mode-controlled film bulk acoustic resonators (FBARs) operating up to 56GHz.