RF-MEMS filters manufactured on silicon: key facts about bulk-acoustic-wave technology

Abstract

The working principle and performance of state-of-the-art Bulk-Acoustic-Wave (BAW) devices is reviewed. The importance for RF-filters in mobile phone applications is discussed and the benefit of silicon-based technologies highlighted. Challenges in manufacturing of BAWs are briefly reviewed. The most important performance parameters such as resonator bandwidth and Q-values - and their dependency on processing and design are described. Whether monolithic integration "System-On-Chip" together with RFICs or hybrid integration "System-In-Package" makes more sense is discussed. Examples of state-of-the-art in BAW filters in production and ramp-up status are presented.