Nanomechanical resonant structures in silicon nitride: fabrication, operation and dissipation issues

We report the fabrication of silicon nitride mechanical devices with lateral dimensions as small as 50 nm. The measured resonant frequencies of these devices (8.5-171 MHz) are the highest reported for silicon nitride structures. We have employed both electrostatic and piezoelectric excitation of these structures. We have also studied the effects of thin metal films on dissipation in these structures and found that the absence of these metal coatings results in a three to four times higher quality factor of the structures. (C) 2002 Elsevier Science B.V. All rights reserved.