Investigation on the device geometry-dependent reverse recovery characteristic of AlGaN/GaN lateral field-effect rectifier (L-FER)

Abstract

In this work, the dependence of the AlGaN/GaN L-FERs’ reverse recovery characteristics on the device geometry (MOS-controlled channel length) is investigated by TCAD Sentaurus. It is found that the reverse recovery time and reverse recovery loss of the AlGaN/GaN L-FERs are increased with the decrease of MOS-controlled channel length. And, the increase of the applied voltage will lead to much higher increase in reverse recovery time and reverse recovery loss for the AlGaN/GaN L-FERs with shorter MOS-controlled channel length. Based on the above results, the drain-induced barrier lowering effect is regarded as the reason for the inferior reverse recovery characteristics of the AlGaN/GaN L-FER with short MOS-controlled channel length. Because, the decrease of MOS-controlled channel length and the increase of the applied voltage will lead to the significant reduction in barrier thickness, which makes the electron more easily transit from the Ohmic contact of anode to cathode-side gate edge in high frequency, subsequently making it difficult to reach equilibrium state.