SCANNING-TUNNELING-MICROSCOPY CHARACTERIZATION OF THE MORPHOLOGY OF FE C MULTILAYERS GROWN ON SILICON SUBSTRATES/

Fe/C multilayers have been deposited by rf sputtering on two silicon s ubstrates with a significant difference in surface quality. Scanning t unneling microscopy (STM) shows a roughness replication process: the s moother the substrate, the smoother the final surface. Both samples pr esent a Gaussian height distribution. The fractal analysis of the STM data shows that, for dimensions larger than the grain size, the surfac e can be described as a self-affine fractal with a fractal dimension o f 2.6+/-0.1, which agrees with the prediction of ballistic deposition models without restructuring. For dimensions lower than the grain size , the fractal dimension is close to the Euclidean value 2.