Low-Temperature Growth of A1N thin films on ZnO templates prepared on Ak2O3 substrates

We have investigated the low-temperature growth of AlN layers on ZnO/MgO/c-sapphire with varying growth temperature and Al flux. Single-crystalline AlN layers can be grown at 400degC, which is quite low compared to the conventional growth temperature of 1000degC. The interdiffusion of Al and N into ZnO layers and Zn and O into AlN layers are evaluated by SIMS. It was found that the diffusions of Al atoms were affected by the crystal quality of AlN layers and growth temperature. Very low diffusion length of Al below 100 nm into ZnO was observed at the interface between AlN and ZnO.