A precise method of analyzing O depth profiles in O-ion (16O+)-implanted substrates, by spectroscopic ellipsometry, was developed. The specimens were formed by 180keV 16O+-implantation into Si(111), to O doses ranging from 3 x 1017 to 1018/cm2. Optical characteristics, such as the amplitude ratio angle and phase difference angle versus wavelength of the specimens, were measured via spectroscopic ellipsometry. The 16O+-implanted Si layer was modeled as being a transition layer which was composed of crystalline Si and SiO2. The composition ratio of crystalline Si to SiO2 was assumed to change continuously in the depth direction. Using this model, the amplitude ratio angle versus wavelength and phase difference angle versus wavelength spectra were calculated in reverse by using the effective medium approximation analysis method. In the simulation, fitting was performed in order to correlate the measured characteristics. The simulated O depth profile and the modeled layer structure were compared with actual results obtained by Rutherford back-scattering spectroscopy and cross-sectional transmission electron microscopy.

High-Precision Analysis of Oxygen Depth Profile in 16O+-Implanted Silicon Substrates by Spectroscopic Ellipsometry. H.Iikawa, M.Nakao, B.Gruska, K.Izumi: Journal of the Electrochemical Society, 2004, 151[5], G373-6