Towards macroporous phononic crystal based structures for FBAR applications. Theoretical investigation of technologically competitive solutions

Abstract

The research work of current contribution is focused on the study of periodic macroporous arrangements, their designs scaling ability and performance depending on a possible technological imperfection. The studied in this work phononic structures are designed for a subsequent integration into the new class of integrated solutions on a basis of solid mounted film bulk acoustic resonators (SMR FBARs). Devices completed on a basis of developed solutions are intended for front-ends of telecommunication and radar systems applications. The main purpose of the research is an initial step towards enabling an efficient operation of integrated FBAR devices in a broad band or in several frequency bands using a multiple bandgap reflecting solid arrangements that ensure the isolation of acoustic energy within the piezoelectric layer for selected operation bands. The possibility of technological integration of periodic structures into the FBAR platform is a main critical point that limits the application of certain approach. Proposed in current work phononic crystal macroporous arrangements can be applied to improve an isolation of film bulk acoustic modes for SMR at specific frequencies; improve isolation and spatial separation of FBAR filter banks; enable an efficient operation of switchable and tunable SMR FBARs.