In-plane nanoelectromechanical resonators based on silicon nanowire piezoresistivedetection

Abstract

We report an actuation/detection scheme with a top-down nanoelectromechanical system(NEMS) for frequency shift based sensing applications with outstanding performance. Itrelies on electrostatic actuation and piezoresistive nanowire gauges for in-planemotion transduction. The process fabrication is fully CMOS (complementarymetal–oxide–semiconductor) compatible. The results show a very large dynamic range ofmore than 100 dB and an unprecedented signal to background ratio of 69 dB providing animprovement of two orders of magnitude in the detection efficiency presented in the stateof the art in NEMS fields. Such a dynamic range results from both negligible1/f noise and very low Johnson noise compared to the thermomechanical noise. This simple lowpower detection scheme paves the way for new class of robust mass resonant sensors.