The Improvement Breakdown Voltage of GaN on Si Pin Diode by Stepped Sidewall Treated with Fluorine Plasma

In this work, we show a GaN-on-Si quasi vertical PiN diode via the combination of stepped sidewall and fluorine plasma treatment. We achieved a 43.2% increase in breakdown voltage (V
BR
). Meanwhile, the off-state leakage is greatly reduced. The diode with stepped sidewall treated with fluorine plasma achieved a low specific on-resistance (Ron,sp) of 0.51 mΩ·cm
²
, and a high Baliga's figure of merit (BFOM) of 0.83 GW/cm
²
. On the one hand, this work demonstrates the effect of the combination of stepped sidewall and fluorine plasma treatment of GaN-on-Si quasi vertical PiN diode, and on the other hand, shows a broad prospect of GaN on Si PiN diode for power electronics application.