Simulation and Modeling of Microsensor Structures Using Multiphysics Tool

It is generally believed that simulation software tools can analyze and solve complex problems associated with sensor properties. But is this really true? How much can we rely on simulation results? How well does the simulation match with the measurements of fabricated devices? Several microsensor structures were designed, simulated, fabricated, and measured. A comparison between the simulated and measured results was performed. The discrepancies between the measured and simulated results were studied to determine the reason for the differences. We have studied three different sensor cases. The first sensor type was a micro-machined micro-bolometer. In the second case a magnetic microsensor was studied to find out the design guidelines for the optimization of a micro-coil used for onboard reference magnetic field generation. Several different micro-coils were fabricated and characterized. The third case examined an integrated micro-heater used as the heat source needed to provide the operating temperature of gas sensors. After the creation of models´ geometries, the most difficult part was determining the correct model material parameters. Problems in model evaluation emerged after the fabrication of the structure, and as in many cases, a direct measurement of the investigated physical quantity was either impossible or was not accurate enough.