Thermally Induced-Noise Reduction Using an Electrostatic Force Feedback

H. Lee, and J.V. Clark
Purdue University, West Lafayette, IN, USA

In this paper we present a method to mitigate the effect of thermally-induced noise in Micro-Electro-Mechanical Systems (MEMS) through a force feedback circuit. Inherent noise-induced vibrations, which would be inconsiderable in macro scale, are considered as a limitation in micro- and nano- scale since it diminishes the high performance of MEMS devices. For instance, depending on the stiffness of a structure, the amplitude of a noise would severely limit the resolution of the resulting displacement to several nm, which is undesirable for highly sensitive devices used in atomic scale manipulations such as atomic force microscope (AFM). Using COMSOL Multiphysics, the force-displacement transducer is combined with the SPICE circuit that corresponds to the force feedback loop.