Design optimization of a high temperature 1.2 kV 4H-SiC buried grid JBS rectifier

1.2 kV SiC buried grid junction barrier Schottky (BG-JBS) diodes are demonstrated. The design considerations for high temperature applications are investigated. The design is optimized in terms of doping concentration and thickness of the epilayers, as well as grid size and spacing dimensions, in order to obtain low on-resistance and reasonable leakage current even at high o temperatures. The device behavior at temperatures ranging from 25 to 250 C is analyzed and measured on wafer level. The forward voltage drop of 1.1 V at 100 A/cm ² and 3.8 V at 1000 A/cm ² is measured, respectively. At reverse voltage of 1 kV, a leakage current density below 0.1 μA/cm ² and below 0.1 mA/cm ² is measured at 25 and 250°C, respectively. This proves the effective shielding effect of the BG-JBS design and provides benefits in high voltage applications, particularly for high temperature operation.