AlN films grown on diamond and silicon carbide

Structural changes in surface layers of CVD AlN films were studied by the reflection high-energy electron diffraction technique. Film thickness was varied from 0.2 to 20 mu m. Single crystals of diamond, silicon carbide and also bilayered structures of natural diamond/CVD diamond films were used as substrates. On the (111) surfaces of natural diamond, (111) CVD diamond films and (00.1) 6H-SiC at AlN thickness up to 1 mu m one can observe the epitaxial correspondence between the growing him and the substrate: (00.1) [11.0] AlN//(111) [110] C-alpha or (00.1) [10.0] AlN//(00.1) [10.0] 6H-SiC. At larger film thickness the epitaxial growth was replaced gradually by the formation of one of axial textures for which the planes (00.1), (10.3) or (11.4) of wurtzite-like aluminum nitride were parallel to the substrate. During the epitaxial growth the twinning structures with the twinning planes of types (10.1) and (11.1) were observed. (C) 1999 Elsevier Science S.A. All rights reserved.