The on-resistance limits of high cell density power MOSFET´s

In this paper, the on-resistance limits of low-voltage power VDMOSFET´s and trench power MOSFET´s are studied, based on an analytical approach and 2D device modelling. It is shown that, unlike VDMOSFET, the trench MOSFET performance is not limited by the “JFET effect”. From a theoretical point of view, for N-channel devices, the 60 V optimized trench MOSFET would present a specific on-resistance equal to 0.32 mΩ.cm² while the equivalent VDMOSFET would present a specific on-resistance of 0.51 mΩ.cm²