Surface morphology of thin Si layers in SOI structures studied by scaling analysis and Fourier transformation of AFM images

Oxidation is one of the technological ways to manage of the top silicon film thickness for modern VLSI creation. DeleCut wafers are a promissing candidate for ultra thin SOI creation. It is known that thermal oxide has abrupt compositional transition between Si and SiO₂ through one Si atomic layer. Another one is a structural transition layer which is a sum of two Si atomic layers 0.2 nm and ∼0.8 nm on the SiO₂ side of the interface. The experimental investigation of layer-by-layer oxidation process and surface morphologies of the created SOI structures was made in the present work. We show that oxidation is really smooth and a slowdown at the SOI thickness less than 10 nm following oxidation induced defect and stress generation.