PZT transduced high-overtone width-extensional resonators above 1 GHz

Hengky Chandrahalim, Sunil A. Bhave, Ronald G. Polcawich, Jeffrey S. Pulskamp, Roger Kaul
2009 2009 IEEE International Ultrasonics Symposium  
This paper provides the theoretical modeling, simulation, and quantitative comparison that explore the design space of PZT-only (Lead Zirconate Titanate) and PZT-on 3, 5 and 10 µm single-crystal silicon high-overtone width-extensional mode (WEM) resonators with identical lateral dimensions for incorporation into radio frequency microelectromechanical systems (RF MEMS) filters and oscillators. A novel fabrication technique was developed to fabricate the resonators with and without silicon layer
more » ... hout silicon layer using the same mask-set on the same wafer. The air-bridge metal routings were implemented to carry electrical signals while avoiding large capacitances from the bond-pads. We theoretically verified and experimentally measured the correlation of motional impedance (RX ), quality factor (Q), and resonance frequency (f ) with the resonators' silicon layer thickness (tSi) up to above 1 GHz frequency of operation. For identical lateral dimensions and PZT-layer thickness (tPZT ), the resonators with thicker silicon layer have higher f . The resonators with thicker silicon also have higher Q and lower RX up to 900 MHz frequency. 978-1-4244-4390-1/09/$25.00
doi:10.1109/ultsym.2009.5441468 fatcat:4kb3s6h3cvcxphj7q4rlxadake