This technology provides an improved MOSFET structure for power switching applications. An n- GaN reduced surface field (RESURF) region is created using epitaxial growth and selective etching of an n- drift layer. This is followed by ion implantation to achieve n GaN contact regions for the source and drain. This avoids the difficulties in controlling doping levels, leakage current, and electron mobility when using ion implantation alone to achieve the two different doping zones.