Nanoscale growth control of functional thin films on atomically surface-controlled substrates by laser MBE

摘要

The nanoscale growth control of functional ceramic thin films was examined by our originally developed technique, which was based on the nanoscale substrate engineering as well as atomic layer control via laser molecular beam epitaxy (laser-MBE). The atomically controlled surface of the substrate such as the ultrasmooth sapphire (single-crystal Al_2O_3) substrate with atomic steps and atomically smooth terraces was found to enhance atomically layer-by-layer growth as well as self-assembled nucleation along the atomic steps. The novel epitaxial growths could be attained on the physically or chemically controlled substrates, that is, (1) termination-regulated molecular layer-by-layer epitaxy, (2) step-decoration epitaxy resulting in the nanowire or nanodots, (3) room-temperature epitaxial growth of AlN, and (4) self-organized formation of the nanogroove-striped pattern on the film surface.