Materials Characterization of WSi Contacts to n+‐GaN as a Function of Rapid Thermal Annealing Temperatures

Interfacial reactions between sputtered WSi ohmic contacts and single crystal GaN were investigated as a function of rapid annealing temperatures up to 800°C. For annealing temperatures ⩽600°C the metal‐semiconductor interface remained structurally and chemically unaltered. The interfacial phase was observed after annealing at 700 and 800°C. Optimization of this phase and moderate suppression of interfacial irregularities occurred after annealing at 800°C. Our results suggest this contact metallization scheme to be a reasonable choice for high temperature electronics applications, however temperate interfacial irregularity may compromise some device designs.