ABSTRACT
This chapter provides an overview of the basics of bulk acoustic wave (BAW) device physics. It explains the main resonator parameters and presents a concise introduction to the terminologies associated with BAW resonators. The good selectivity and steep transition band offered by the BAW resonators make them excellent components for interstage filters and duplexers used in mobile communication system and wireless applications. The chapter presents various loss mechanisms possible in BAW resonators and discusses their association with the quality factor. It discusses BAW resonator concept and the two generally adopted configurations. The chapter reviews the existing models for BAW device operation. It describes the key performance parameters for BAW resonators and deals with the loss mechanisms in thin-film BAW resonators and its association with the quality factor. The chapter also describes the BAW resonator measurements. BAW devices utilize the converse piezoelectric effect to generate a mechanical resonance from an electrical input.
