AlGaN/GaN Field Effect Schottky Barrier Diode for a Low Loss Switching Device

摘要

We have proposed a novel field effect Schottky barrier diode (FESBD) with a dual Schottky structure combined with an AlGaN/GaN heterostructure in order to obtain a very low on-voltage. This diode has a dual Schottky structure of a very low Schottky barrier metal and a high Schottky barrier metal for obtaining a low on-voltage. The leakage current at a reverse bias was suppressed by the pinch-off based on field effect of a higher Schottky barrier metal, resulting in increasing the reverse breakdown voltage. In this paper, we carried out a planer-type FESBD for a large current operation. The AlGaN/GaN heterostructure was grown by a metalorganic chemical vapor deposition (MOCVD). A dual Schottky structure was fabricated using Ti/Al and Pt. An ohmic electrode was also Ti/Al. As a result, the on voltage of FESBD was below 0.1 V. The reverse breakdown voltage was also over 400 V by pinch-off effect. The switching time of the diode was shorter than 3 ns.