High performance RF-filters suitable for above IC integration: film bulk-acoustic- resonators (FBAR) on silicon

The fundamentals of bulk-acoustic-wave (BAW) devices and the performance of state-of-the-art film bulk-acoustic-resonator (FBAR) filters is reviewed. The key role that high performance RF-filters play in handset applications is discussed and the benefit of silicon technologies outlined. Key processes in manufacturing of FBARs are briefly reviewed. The appealing simplicity of filter modeling and design is presented. Monolithic integration of "system-on-chip" together with RF-ICs is technically feasible and has been demonstrated. Conditions under which this will commercially make sense as compared to hybrid integration "system-in-package" is discussed. Examples of state-of-the-art in BAW filters in production and ramp-up status are presented.