Design, fabrication, and characterization of low forward drop, low leakage, 1-kV 4H-SiC JBS rectifiers

The 1-kV 4H-SiC planar junction barrier Schottky (JBS) rectifiers were designed, fabricated, and characterized. Different p+ implantation dosages and activation anneal methods were used to determine an optimum baseline process. Using the optimized process, the forward drop of our JBS rectifiers is <1.5 V while the reverse leakage current density is <1×10^-5 A/cm^-2. Blocking voltage>1 kV was achieved using a single-zone junction termination extension termination. It was shown experimentally that 4-μm p-type implantation window spacing gives an optimum tradeoff between forward drop voltage and leakage current density for these rectifiers, yielding a specific on-resistance of 3 mΩ·cm².