Complete optical analysis to obtain the absorption coefficient of the interstitial oxygen vibration in silicon

The concentration of interstitial oxygen in single-crystal silicon is linearly dependent on the absorption coefficient of the corresponding local vibration in the infrared. This absorption coefficient is usually determined from the spectral absorbance. Optical and geometrical parameters of the investigated sample influence the measurements and lower the determination precision. Instead of this standard method, the application of complete optical analysis for the investigated sample is shown. The proposed method overcomes most problems that are involved in the standard procedure. The thickness and degree of rear surface damage of the reference sample are immaterial. The error of the standard determination procedure is discussed in terms of its dependence on the degree of sample surface damage.