This contribution analyses the impact of nonlinearities on the sensitivity of micro‐electro‐mechanical sensors measuring quantities based on a change in resonance frequency. The considered sensor is an array of cantilevers which have an integrated actuator and sensor. The mathematical model presented to describe the motion of this array is based on a coupled thermoelastic equation of motion which has a forced and a parametric excitation. Finally, a concept is presented to utilize a two‐to‐one internal resonance to increase a micro system's vibrational sensitivity. (© 2017 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)