Self-assembled island formation of LiNbO3 by pulsed laser deposition on α-Al2O3 substrate

LiNbO(3)(0001) films were grown epitaxially on alpha-Al(2)O(3)(0001) substrate by pulsed laser deposition (PLD). The initial growth of LiNbO(3) film on atomically flat sapphire (alpha-Al(2)O(3)) substrates has been investigated by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The two-dimensional LiNbO(3) layer with thickness of about 1 nm was formed before three-dimensional growth occurred. Subsequently grown islands were distributed uniformly on the terrace surface. This result indicates that the LiNbO(3) grows in the Stranski-Krastanov growth mode. Judging from X-ray 2 theta-theta diffraction (XRD) and reflection high-energy electron diffraction (RHEED) patterns, high quality epitaxial film was obtained. And, the film emitted visible photoluminescence (PL) at room temperature. (C) 1998 Elsevier Science B.V.