Wurtzite AlBN thin films were fabricated using flow-rate modulation epitaxy (FME), wherein group-III and group-V sources are alternatively supplied to the growing surface. A 350-nm -thick wurtzite Al1-x Bx N (x∼0.015) film grown by FME exhibited a single sharp peak in the ω-2θ scan of x-ray diffraction, a smooth surface with the root-mean-square roughness of 3.4 nm, and a sharp epitaxial interface with SiC(0001) substrate, whereas that prepared by conventional metalorganic chemical vapor deposition contained faceted columnar AlBN (1 1_ 01) crystallites several ten nanometers in width in an AlBN(0001) matrix. FME is useful for fabricating high-quality wurtzite AlBN thin films, because it suppresses polycrystallization through enhancement of the surface migration of boron atoms.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)