Initial growth behaviour of LiNbO3 films on α-Al2O3 substrates with atomic scale step structure

Evolving morphology of the LiNbO3 films growth on C(001), A(110) and R(102) α-Al2O3 substrates with atomic scale step structure was investigated during the initial stage of the growth. On C(001) substrate, LiNbO3 nucleated randomly irrespective of the step structure on the substrate, while this material showed preferential nucleation along the step edges on the surface of A(110) and R(102) substrates. This tendency of initial growth of LiNbO3 on A(110) and R(102) substrates enhances the step-flow growth, allowing the fabrication of nanometric wire and smoother films.