Over 2000 V FLR termination technologies for SiC high voltage devices

The Field Limiting Ring (FLR) termination structures are examined in order to confirm the high voltage technology of SiC diodes and FETs. Elemental devices with planar FLR terminations are fabricated and their reverse I-V characteristics are determined using 4H n-type SiC. First demonstrations of breakdown voltages higher than 2000 V are succeeded by using FLR terminations. Optimal FLR spacing of the boron termination is wider than that of the aluminum case. This difference is considered to show that the lateral diffusion is remarkable for the process using boron implantation.