Atomic topography change of SiO2/Si interfaces during thermal oxidation

Using an Si(111) surface with atomically flat, wide terraces, the topographic change Of SiO2/Si interfaces during thermal oxidation was investigated at an oxidation temperature of 1050degreesC using an atomic force microscope, Vestiges of two-dimensional oxide-island growth were observed at the interface, Then, a histogram for roughness height distribution based on atomic force microscope (AFM) data was plotted in order to evaluate the roughness within the ten-aces at the interface instead of the root mean square (RMS). This method revealed that the SiO2/Si interface consists of at least three layers separated from one another by 0.3 nm. This result provides evidence of the layer-by-layer model breaking down at the SiO2/Si interfaces.