Adsorbed Mass Fluctuations of a Micro/Nanoresonator Surrounded by an Arbitrary Gas Mixture

Micro/nanoresonator mass and frequency fluctuations caused by sorption processes on a resonator surface are investigated. Arbitrary gas mixture is considered, assuming that particle arrivals at the surface are all poissonian in nature, independent from each other, and that sorption dynamics follows the Langmuir isotherm. Power spectral density for mass fluctuations are derived using the analytical Langevin approach. The results of simulations are given for a silicon micro/nanocantilever in the atmosphere of four gases. The presented analysis is useful for calculation of the ultimate performance of MEMS/NEMS sensors and oscillators, as well as for investigation of the possibilities of their parameters optimization by choosing the gas mixture in the cantilever´s atmosphere. Another objective is to consider the possibility of identification of gases in the mixture, based on the power spectral density of the adsorbed mass fluctuation