Nanomechanics

Electromechanical systems are being miniaturized, following the trend in commercial transistor electronics. First generation miniature electromechanical systems, Microelectromechanical Systems (MEMS), have been successfully integrated as low frequency sensors and actuators. With the advances in surface nanomachining processes, their submicron counterparts Nanoelectromechanical Systems (NEMS) are emerging as strong candidates for a host of technological applications. Their high operation frequencies, low power requirements, compactness and full integrability with modern semiconductor electronics offer exciting device prospects such as ultrafast sensors and actuators and mechanical signal processing components. There are, however, a number of technological and fundamental challenges to NEMS optimization, the most important being the unprecedented energy losses and resonance instabilities due to their extreme surface to volume ratios and small sizes.

In this talk, I will introduce nanomechanics with emphasis on device fabrication and RF measurement techniques. I will focus on our recent results on effects due to surfaces and surface related phenomena in NEMS. In particular, I will discuss prospects for NEMS based mass spectrometry in the light of our recent mass sensitivity measurements in the attogram (10^-18 g) range. I will also propose NEMS based energy dissipation measurements in surface adsorbates.

[Work done in collaboration with Y.T. Yang, X.M.H. Huang and M.L. Roukes.]