High off-state voltage (4266 V) diamond metal oxide semiconductor field effect transistors

In this study, diamond metal–oxide semiconductor field-effect transistors (MOSFETs) with NO2 p-type doping and Al2O3 passivation layer having a gate-to-drain length of 50 μm showed a record high off-state breakdown voltage of 4266 V. A MOSFET with a gate-to-drain length of 11.5 μm exhibited a maximum drain current density of 409 mA/mm with a low on-resistance of 80.3 Ω·mm and a maximum available power density (Baliga’s figure of merit) of 162 MW/cm2. Furthermore, the subthreshold swing was determined to be 227 mV/dec with a corresponding interfacial states density of 7.07 × 1012 eV−1 cm−2. This study explores the feasibility of diamond MOSFETs in withstanding high off-state voltage for prospective applications in power electronics.