SiC Schottky-Barrier Diode without Ion-Implanted P-Type Regions

This paper shows results of SiC Schottky diodes fabricated without ion-implanted P-type regions. Diodes with blocking voltages up to 4,500 V are demonstrated utilizing an epitaxial P-type ring with sloped edges for the edge termination. Reverse-bias currents at temperatures higher than 60°C, and at nominal blocking voltages of 650 V, 1200 V, and 1700 V, are shown to match the theoretical values based on the two fundamental current mechanisms: tunneling and thermionic emission. In comparison to JBS and MPS diodes, the whole anode area is active, which enables homogeneous current flow and comparable isothermal characteristics without the usual wafer thinning. In addition, the non-thinned wafer results in larger thermal capacitance, allowing for higher repetitive peak surge currents for the same junction temperature within the maximum operating temperature of 175°C.