Ohmic performance of ZnO and ITO/ZnO contacted with n-type GaN layer

The electrical characteristics of the ITO/ZnO multilayers contacts on n-GaN have been investigated. Ohmic behavior and the measured special contact resistance of 3×10−4 Ω cm2 were achieved for the ITO/ZnO/GaN structure annealed at 500°C for 5 min in hydrogen ambient. These results could be attributed to the ITO/n-ZnO/n-GaN isotype conjunction and the quantum confinement effect in a thin ZnO buffer layer.