Design and fabrication of planar guard ring termination for high-voltage SiC diodes

An optimized multiple floating guard ring structure is investigated for the first time as an edge termination method for high voltage 4H-SiC planar de vices. Simulations were performed to investigate SIC guard ring termination , and determine the optimum guard ring spacing for planar diodes with up to four floating rings. Simulated optimized designs predicted breakdown value s from 40% of the ideal breakdown with a single ring, to 84% of the ideal v alue for diodes with four rings. Implanted 4H-SiC pn diodes with optimized guard ring designs were fabricated and results correlated to simulation. Ex perimental breakdown values of 1.2-1.3 kV for guard ring structure with fou r rings were in good agreement with simulated results. (C) 2000 Elsevier Sc ience Ltd. All rights reserved.