Demonstration of 1200 V/1.4 mΩ cm ² vertical GaN planar MOSFET fabricated by an all ion implantation process

We present a vertical GaN planar metal-oxide-semiconductor field-effect transistor (MOSFET) fabricated by an all ion implantation process. The fabricated MOSFET shows an on-resistance of 2.78 mΩ cm 2 and a breakdown voltage of 1200 V, by applying the short cell pitch design to reduce the on-resistance and a Mg and N sequential implantation to improve the breakdown voltage of the pn-junction. By evaluating each on-resistance component in the fabricated vertical GaN planar MOSFET using the simultaneously formed test structures, an effective on-resistance of the active region excluding the source parasitic resistance is 1.4 mΩ cm 2 . Consequently, it was demonstrated that an all ion implantation process can fabricate a vertical GaN planar MOSFET with a high breakdown voltage and low on-resistance. This result will greatly contribute to the realization of GaN power devices.