Integration of MOSFET Transistors in MEMS Resonators for Improved Output Detection

Micro-electromechanical (MEM) laterally vibrating square resonators and beams, fabricated via a prototyping technology combining FIB-micromachined gaps with conventional UV lithography in 1.35 mum thick SOI are presented. Resonators with both capacitive and MOSFET detection and gaps of ~100 nm are demonstrated. Resonance frequencies of 32 MHz and 13 MHz were measured for squares and beams, respectively. The square shaped resonators have Q-factors in the order of 4000. This paper reports on a vibrating body MOS transistor active detection scheme integrated in a MEMS fabrication process to improve the signal read out.