Infrared spectroscopy of thin silicon dioxide on silicon

An infrared technique has been devised to study the structure of very thin films on substrates of high refractive index. Optical spectrum amplification of three orders of magnitude is theoretically available. A series of refractive index enhanced multiple internal reflection spectra reveals a clear thickness-dependent structural transformation in thermal SiO2. The spectra suggest a shift in ring statistics, from smaller to larger, with increasing distance from the oxide-silicon interface.