This paper reports on vertical GaN Schottky barrier diodes (SBDs) fabricated on a free-standing GaN substrate with different sizes of Schottky electrode. The fabricated SBDs with 3 × 3 mm2 Schottky electrodes exhibited both a forward current of 50 A and a blocking voltage of 790 V. To our knowledge, the characteristics of operation with a simultaneous high forward current and high blocking voltage are reported for the first time for vertical GaN SBDs on free-standing GaN substrates. The dependence of these characteristics on the Schottky electrode size is also reported in detail.

In this paper, we report on a vertical GaN trench MOS barrier Schottky (TMBS) rectifier for attaining low leakage current at high temperature and high reverse voltage. At 200 °C, a high blocking voltage of 750 V was achieved at a leakage current of 1 mA/cm2. To the best of our knowledge, this blocking voltage is the highest ever reported for GaN Schottky rectifiers operating at such a high temperature. Furthermore, the fabricated TMBS rectifier operated at large forward currents up to 10 A. These results verify that the developed vertical GaN TMBS rectifiers have great potential as high-power and high-temperature devices.