The impact of the Island Layout on the Performance of the 4H-SiC Floating Island Device

Abstract

Abstract The Floating Island (FI) structure in 4H-SiC device is able to break the “SiC 1D-Limit”. This is achieved by transforming the electric field distribution in the drift region from a single-triangle profile into a multiple-triangle profile, both of which have the same triangle height and width. With such an electric field distribution, the trade-off between breakdown voltage (BV) and specific ON-resistance (RON,sp) can be significantly improved. In this paper, the 4H-SiC FI Junction Barrier Schottky (JBS) diodes with four different island layouts, namely the stripe, the hexagon island, the hexagon hole and the hexagon cell, have been fabricated and tested. The results show that RON,sp is virtually the same at the same N-type area ratio, but BV diverges at the same N-type area ratio for different layouts. The stripe layout has the highest BV among the four island layouts. A BV of 2200V and RON,sp of 3.8mΩ.cm2 has been achieved with the stripe design.