A New 200 V Dual Trench MOSFET With Stepped Oxide for Ultra Low RDS(on)

A new 200 V rating power trench MOSFET having dual trench structures with stepped oxide in the drift region, used here for the first time has been proposed and implemented to obtain higher breakdown voltages with lower drain-source on-state resistance, R
_DS(on)
. A more efficient reverse blocking voltage capability to reduce the drift region resistance by increasing doping concentration of the drift region has been demonstrated by this approach. We obtained Rsp = 215mΩ·mm
²
at the breakdown voltage of 225 V from the first fabricated devices, and Rsp = 196 mΩ·mm
²
at 224 V from the simulated devices, which positions them as the best-in-class on-state drain-source specific resistance, Rsp, with comparable voltage rating devices.