Design and Fabrication of 3300V 100mΩ 4H-SiC MOSFET with Stepped p-body Structure

In this paper, a 3300 V 100 mΩ 4H-SiC planar MOSFET with stepped p-body structure was designed and fabricated. 2D TCAD tool was used to design the MOSFET cell and field limiting ring junction termination structure. The junction field-effect transistor (JFET) region was optimized to get better trade-off between on-resistance and maximum gate oxide electric field in off-state. The stepped p-body was formed by two step ion implantations to transfer the avalanche point from the edge of the p-body to the deep p+ area. Finally, the threshold voltage of 1.7 V, subthreshold swing of 188 mV/decade and the average interface state density of 5.35E11 cm−2eV−1 were obtained from the measured transfer curve.