Design and Simulation of 1.2kV SiC Super-junction SBD with Vertical Variation Doping

In this paper, a 1.2kV SiC super-junction SBD with vertical variation doping (VVD-SJ-SBD) is proposed and investigated by Sentaurus TCAD. It is known that the breakdown voltage (BV) of conventional SiC super junction Schottky diode (C-SJ-SBD) is sensitive to the doping of p-type region due to the essential charge balance required in a SJ-based structure, resulting in a poor process tolerance. The n-type epi-layer of SiC VVD-SJ-SBD proposed in this paper is divided into three layers. The middle layer is heavily doped, and sandwiched between two lightly doped layers. By introducing such vertical variation doping profile into the epitaxy, the SiC VVD-SJ-SBD structure can reduce the sensitivity of BV to the doping concentration of p-type region, resulting in the improvement of the process window. Furthermore, the influence of parameters variation on BV of SiC VVD-SJ-SBD is addressed as well.