Improved SiC JBS rectifier based on P+ grids on P-well structure

Compared with the common junction barrier Schottky (JBS) rectifier, a recently reported SiC JBS device with P+ grids on P-well (POP) exhibited an increasing breakdown voltage and Baliga´s figures of merit (4×Vbr²/Ron) due to a uniform electric field. To further enhance the performance, an improved POP structure is proposed. It features the upper part of the p-well sharing the same width with the p+ region to reduce the electric field crowding at the corner of that region. Detailed discussions about the device parameters combined with simulation results show that with the same photomask set and similar process flow, the BFOM of this device is 5% more than that of the original structure, and the breakdown voltage can be increased by 8.5%.