SURFACE-ROUGHNESS AND INPLANE TEXTURING IN SPUTTERED THIN-FILMS

Real surfaces are not flat on an atomic scale, Studying the effects of roughness on microstructural evolution is of relevance because films are sputtered onto nonideal surfaces in many applications. To this end , amorphous rough substrates of two different morphologies, either elo ngated mounds or facets, were fabricated. The microstructural developm ent of films deposited onto these surfaces was examined. In particular , the development of a preferred crystallographic orientation in the p lane of growth in 400 nm thick Mo films grown on the rough substrates was studied using scanning electron microscopy, transmission electron diffraction, and high resolution x-ray diffraction (using phi scans in the symmetric grazing incidence x-ray scattering geometry with a sync hrotron light source). It was found that the degree of texturing was d ependent upon the type of roughness and its orientation during deposit ion. By limiting the average oblique angle of incident adatom flux, ro ugh surfaces slowed the development of in-plane texture. Comparison be tween experimental data and theoretical predictions showed that a rece nt analytical model is able to reasonably predict the degree of textur ing in films grown onto these surfaces, (C) 1998 American Institute of Physics.