Ideal N-type SiC/metal Contacts by Reduction of the Density of Interface State

The ideal SiC/metal contacts were formed by controlling the barrier height on the ideal SiC surface. The ideal SiC surface was realized by lowering the density of surface states owing to SiC surface hydrogenation. The mechanism of surface hydrogenation was studied in this paper. Using the surface hydrogenation treatment, SiC Schottky diodes with ideality factor of 1.2-1.25 and ohmic contacts with specific contact resistance of 5 times 10^-3~ 7 times 10^-3 Omega cm2 were obtained below 100degC for the first time. Its advantages lay in not only avoiding the annealing at 800-1200degC for Ohmic contacts in the conventional process, but also improving the electrical performances of SiC Schottky diodes.