High-Voltage and High- $I_{\text {ON}}/I_{\text {OFF}}$ Vertical GaN-on-GaN Schottky Barrier Diode With Nitridation-Based Termination

We report a high-performance vertical GaN-on-GaN Schottky barrier diode (SBD) with a planar nitridation-based termination (NT) technique. The developed NT-SBD with nearly ideal Schottky contact exhibits a forward current density over kA/cm
²
, current swing over 10
¹³
, and differential specific ON-resistance of 1.2 cm
²
. The breakdown voltage is boosted from 335 V for unterminated-SBD to 995 V after termination, whereas a high ON/OFF current ratio (I
_ON
/I
_OFF
at -600 V) of ~10
⁸
is realized in the NT-SBD. It has been verified that the NT technique can favorably modify GaN surface condition, leading to suppressed leakage current at the junction edge and enhanced breakdown voltage.