Validated electro-thermal simulations of two different power MOSFET technologies and implications on their robustness

Power MOSFETs integrated in modern Smart Power switches feature a substantial high current capability due to the very low value of their transconductance coefficient K. In this paper we demonstrate that the trend related to the increasing current capability implies a reduced thermal stability range which may lead to less robust devices. Electro-thermal simulations of two test chips featuring two different technologies show that the higher the value of K, the less stable the device thermal behavior. Simulation results have been validated by means of temperature measurements performed using an integrated temperature sensor.