580 v Breakdown Voltage in Vertical Diamond Trench MOSFETs with a P^--Drift Layer

This letter reports the successful demonstration of large-current and high-voltage (001) vertical-type two-dimensional hole gas (2DHG) diamond trench metal-oxide-semiconductor field-effect transistors (MOSFETs) with a p-drift layer. The fabricated transistor demonstrated a maximum drain current density of 210 mA/mm, a field-effect-mobility of 61 cm2V-1s-1, and a specific on-resistance of 23 mOmega cm2. Moreover, a high breakdown voltage of 580 V with a gate-drain length of 10 mu\text m was obtained, which is the highest value reported for a vertical-type diamond MOSFET to date. These characteristics indicate that a vertical-type diamond MOSFET using a p-drift layer may be used to realize a p-channel power device with a high breakdown voltage and low on-resistance.