We investigate fluctuations in the mode amplitudes of vibrating micro mechined cantilevers in a gaseous environment. The movement of a micro-cantilever in thermal equilibrium consists of an superposition of its vibration modes. Each vibrating mode represents a degree of freedom of the vibrationg system, with the thermal energy given according to the equipartition theorem. The excitation of a mode is created by the molecules of the environment impinging on the cantilever surface. All modes have the same thermal energy their mean square amplitude is completely determined by the ambient temperature. The only difference bertween various environmental conditions occurs in the temporal behavior of the randomly vibrating cantilever. Thus only in the time correlation functions of the mode amplitudes the temporal behavior is notable. THe behavior of the correlation functions is investigated for different pressure conditions for the case of a gaseous environment.
Journal: TechConnect Briefs
Volume: Technical Proceedings of the 1999 International Conference on Modeling and Simulation of Microsystems
Published: April 19, 1999
Pages: 617 - 619
Industry sector: Sensors, MEMS, Electronics
Topics: Chemical, Physical & Bio-Sensors, MEMS & NEMS Devices, Modeling & Applications