Ultra temperature-stable bulk-acoustic-wave resonators with SiO2 compensation layer.
This paper describes temperature compensated bulk acoustic-wave resonators (BAR) with temperature coefficient of frequency (TCF) less than 1 ppm/degrees C at above 3 GHz. The temperature compensation is produced from the unique physical property of silicon dioxide's positive TCF, unlike most other materials that have negative TCF. Two types of resonators have been explored: film bulk acoustic resonator (FBAR) composed of Al/ZnO/Al/SiO2 on a surface micromachined cantilever that is released by XeF2 vapor etching and high-overtone acoustic resonator (HBAR) composed of an Al/ZnO/Al resonator on a bulk micromachined SiO2/Si/SiO2 supporting substrate.
Yu
Hongyu
H
Department of Electrical Engineering, University of Southern California, Los Angeles, CA, USA. hongyuyu@usc.edu
Pang
Wei
W
Zhang
Hao
H
Kim
Eun Sok
ES