Numerical modeling of a micromachined thermal conductivity gas pressure sensor

We have developed a software package that simulates the operation of a silicon micromachined CMOS thermal conductivity gas pressure gauge. The performance of actual devices was compared against the simulated operation and was found to be in good agreement. The 3-dimensional simulation was reduced to two 2-dimensional simulations to reduce complexity. The two equations resulting from steady state energy balance considerations were discretized and an iterative nonlinear Gauss-Seidel procedure applied to solve the system of equations. Temperature profiles and contours were calculated and the effect of geometric and materials modifications was demonstrated.>