Thermal simulation of surface micromachined polysilicon hot plates of low power consumption

A simple, IC compatible, surface micromachined polysilicon membrane was technologically designed and thermally simulated by 3D finite element “COSMOS” program in order to investigate its capability to work as a micro hot plate for a gas sensing test structure of low power consumption. For an optimised lay-out based on four “poly” suspended bridges and a central “poly” pillar supporting the 110×110 μm “poly” membrane separated from the silicon substrate by 1 μm of air gap, temperatures as high as 673 K were obtained for an input power of 100 mW