The effect of edge-terminated structure for lateral AlGaN/GaN Schottky barrier diodes with gated ohmic anode

We have investigated the effect of an edge-terminated structure in the anode of a gated ohmic anode AlGaN/GaN lateral Schottky Barrier Diode (SBD) device. The edge-terminated structure in the anode serves as a kind of field plate, which suppresses a reverse leakage current and improves a switching characteristic by reducing trapping effect at the active region. According to our two-dimensional simulation results, the electric field concentration near the edge of the anode was relatively reduced by the edge-terminated structure. For the fabricated devices, it was exhibited that the diode with proposed structure has lower reverse leakage current density without degradation of the forward current density, compared to the diode without the edge-terminated structure. In addition, the pulse response degradation was significantly improved from 16 to 3.5% at the forward voltage of 1.5 V when the reverse voltage of -100 V was applied.