INTERFACIAL ROUGHNESS CORRELATION IN MULTILAYER FILMS - INFLUENCE OF TOTAL FILM AND INDIVIDUAL LAYER THICKNESSES

A series of W/C multilayer films sputter deposited on Si(100) substrates with total thickness ranging from 400 to 6400 angstrom and bilayer period from 20 to 160 angstrom were examined to explore the variation of interfacial roughness and interfacial roughness correlation with film thickness and period. The films were characterized with x-ray diffractometry. Average interfacial roughness is obtained from conventional (theta, 2-theta) scans, while information on roughness correlation is extracted from rocking-curve (transverse-profile) analysis. The magnitude of the roughness is found to depend more on bilayer period than on total film thickness. The observations suggest that interfaces retard the evolution of surface roughness and that thin "restarting" layers may be used to control the growth morphology of thin films.