Thermal-Mechanical Analysis of a Multi-Layer MEMS Membrane
This paper examines the modelling of a square four layer MEMS membrane for a combined thermal and structural analysis. The membrane consists of four dissimilar layers, two polymer and two metal layers. Only the bottom polymer layer is fixed to the substrate and only around the perimeter. The second polymer layer is sandwiched between two metal layers. Dielectric loss in this polymer induced by a high frequency AC voltage between the metal layers heats the membrane and deforms it. Due to the extreme aspect ratios of the membrane, up to 3,500:1 for the metal layers, solid modelling proves inefficient and alternatives are examined in this paper. It is shown that for this specific membrane set-up axisymmetric modelling yields results that are sufficient for parameter optimization. The shortcom-ings of this method are presented as well.