Low Interface State Densities At Al2o3/Gan Interfaces Formed On Vicinal Polar And Non-Polar Surfaces

Ni/Al2O3/GaN structures with vicinal GaN surfaces from the c- or m-plane were formed. Then, electrical interface properties of the structures were systematically investigated. It was found that interface state density (D-it) at the Al2O3/GaN interface for the c-plane is higher than that for the m-plane, and post-metallization annealing is quite effective to reduce D-it for both c- and m-planes. As a result, the low D-it value of similar to 3x10(10)eV(-1)cm(-2) was demonstrated for both planes.