Effect of interface native oxide layer on the properties of annealed Ni/SiC contacts

The near-SiC-interfaces of annealed Ni/SiC contacts were observed directly by high-resolution transmission electron microscopy (HRTEM). 1 nm native oxide layer was observed in the as-deposited contact interface. The native oxide layer cannot be removed at 650 degrees C through rapid thermal annealing (RTA) and it was completely removed at 1000 degrees C RTA. The residue of native oxide layer resulted in the Schottky characteristics. High temperature annealing (>950 degrees C) not only removes the oxide layer in the near-SiC-interface, but also forms a well arranged flat Ni2Si/SiC interface, which contribute to the formation of ohmic behavior.