Current Distribution in the Various Functional Areas of a 600V SiC MPS Diode in Forward Operation

The forward current distribution in SiC 600V merged pn-Schottky (MPS) diodes is visualized with the help of emission microscopy at various current densities. It is shown how the light emission develops with increasing current densities and extends from the Schottky contact areas into the pn junction areas. Large p + -regions e.g. in the edge termination contribute first by minority carrier injection, whereas the smaller p + hexagonal cells and the p + grid follow subsequently.