High-rate growth of bicrystal ZnO films on a rhombohedral sapphire plane

A method for growing bicrystal ZnO films using the specific features of magnetron sputtering and the orienting effect of a rhombohedral sapphire plane is proposed. It is shown that the successive application of two deposition regimes ($\sim$2 and $\sim$16 nm/s) leads to the formation of a bicrystal film with the (110)-oriented lower sublayer and the (002)-oriented upper sublayer. Recrystallization annealing at 1000$^\circ$C for 10 h does not affect the upper (002)-oriented layer and induces stress relaxation in the lower (110)-oriented layer.