High-voltage 4H-SiC trench MOS barrier Schottky rectifier with low forward voltage drop using enhanced sidewall layer

Abstract

In this paper, a 4H-SiC trench MOS barrier Schottky (TMBS) rectifier with an enhanced sidewall layer (ESL) is proposed. The proposed structure has a high doping concentration at the trench sidewall. This high doping concentration improves both the reverse blocking and forward characteristics of the structure. The ESL–TMBS rectifier has a 7.4% lower forward voltage drop and a 24% higher breakdown voltage. However, this structure has a reverse leakage current that is approximately three times higher than that of a conventional TMBS rectifier owing to the reduction in energy barrier height. This problem is solved when ESL is used partially, since its use provides a reverse leakage current that is comparable to that of a conventional TMBS rectifier. Thus, the forward voltage drop and breakdown voltage improve without any loss in static and dynamic characteristics in the ESL–TMBS rectifier compared with the performance of a conventional TMBS rectifier.

Understanding High Temperature Static and Dynamic Characteristics of 1.2 kV SiC Power MOSFETs

“…Silicon carbide (SiC) power MOSFETs are believed to be the ideal choice for future power electronics due to many superior properties of the SiC material [1][2][3][4] . Besides the high blocking voltage, small on-state resistance and fast switching speed, another property that researchers are particularly interested in is the high temperature capability of SiC MOSFETs, which is becoming more important as power electronics faces wider applications in harsh environments.…”