A high-performance quasi-vertical GaN Schottky barrier diode (SBD) was successfully fabricated by using a high-quality n ^- -GaN drift layer with a precisely-controlled n-type doping. A high current on/off ratio of 10 ¹⁰ , an ideality factor of 1.03, a low specific on-resistance of 1.41 mΩ·cm ² , and a relatively high breakdown voltage (BV) of 250 V have been achieved for the SBD without edge termination. Furthermore, with an Argon-implanted termination, the as-fabricated GaN-on-Si SBD shows a record high BV of 405 V, yielding a critical electric field of ~ 2 MV/cm, while the forward conduction characteristics are well maintained.