Micromachined polysilicon power dissipation: simulation and experiment

In this paper, we present and implement a novel procedure for the accurate simulation of the thermoelectric effects which determine micromachined structures' behavior. This approach is simple to discretize, with rapid numerical convergence properties, and it yields results which are in very good agreement with experimental observations. We employ this procedure in particular to calculate P/sub 1ATM//P/sub VAC/, where P/sub 1ATM/ (resp. A/sub VAC/) denotes heat conducted down the micromachined structure supporting arms at one atmosphere (resp. vacuum) when the device is at the same average temperature. We show that P/sub 1ATM//A/sub VAC/ may not be unity, as had been earlier assumed, but is independent of input current. Finally, for a special class of devices, an analytical formula is obtained for P/sub 1ATM//P/sub VAC/ in terms of device parameters, and this result is also compared with the numerical simulation results.