Large range MEMS motion detection using integrated piezo-resistive silicon nanowire

Electrostatically actuated MEMS devices integrating surface micromachined silicon piezoresistive nanowires were batch processed to investigate a silicon nanowire detection scheme allowing an arbitrary choice of MEMS motion detection range and an increase of nanowire gauge factor measurement stress resolution. It is demonstrated that an in-plane MEMS displacements up to 180 nm with a resolution down to a few Angströms can be achieved as well as a MEMS resonance detection. Results are compared with ex-situ MEMS optical microscopy and in-situ capacitive measurements of MEMS displacement.