Simulation of a thermomechanically actuated gas sensor

The physical dimensions of microsystems make the characteristic times of thermal and mechanical phenomena comparable. Thus, for the first time, we require the coupled analysis of this system. This paper tackles this challenge, presenting a general method to routinely investigate the frequency-domain behaviour of MEMS devices thermo-mechanically excited by an AC heating power. In particular, an application to a gas sensor is presented. For the device we can now correctly determine the amplitude/heating power ratio, given the air and structural damping model, together with the geometry and material description, Characteristics of the method are the use of finite elements for the space-discretization, and spectral analysis for the reduction of mechanical degrees of freedom.