A new vertical GaN Schottky barrier diode with floating metal ring for high breakdown voltage

A vertical GaN Schottky barrier diode (SBD) employing a floating metal ring as an edge termination is described. The breakdown voltage is larger than a device without any termination that has been fabricated on a bulk GaN substrate. Fabricated GaN SBD exhibits a high breakdown voltage of 353 V and very fast reverse recovery characteristics of 28 ns. The breakdown voltage of a device without termination is 159 V. It should be noted that the proposed device does not require any additional processes.