High Breakdown Voltage and Low Specific On-resistance C-doped GaN-on-sapphire HFETs for Low-loss and High-power Switching Applications

High-quality C-doped GaN buffers grown on sapphire substrates were employed for the fabrication of high-power AlGaN/GaN heterojunction field effect transistors (HFETs). The fabricated device exhibited a very high breakdown voltage (BV) over 1350 V and low specific on-resistance (ARDS(ON)) of 3.4 m¿m2. This result is very close to the 4H-SiC theoretical limit and a record achievement for GaN-based HFETs realized on sapphire substrates, to the best of our knowledge.