Frequency stability methods for tensioned micromechanical resonators

In tensioned micromechanical resonators, frequency shifts can be used for bolometric sensors operating at room temperature. To advance these sensors to competitive parameter space, improving sensitivity via characterizing and reducing frequency noise in micromechanical resonators is critical. We measure dual mechanical mode frequency shifts in a tensioned silicon nitride micromechanical resonator. We show one can achieve fractional frequency Allan deviations limited by thermomechanical noise by correcting for common mode frequency drifts.