Al/Ti Schottky barrier diodes with the guard-ring termination for 6H-SiC

In this report, three important technologies for SiC power devices are studied. One is the isolation technology for a p-n junction utilizing the local oxidation technique. For the second, Al/Ti is investigated as a Schottky metal, in which wet etching and the high temperature annealing are applicable. Finally, we propose a guard-ring structure as the edge termination for Schottky barrier diodes to sustain high voltage. The mesa structure of the guard ring is fabricated by local oxidation. The fabrication results showed that the guard-ring structure has improved the breakdown voltage to as high as p-n junction diodes.