Silicon and insulator thickness estimation in SOI by means of spectral estimators applied to transformed infrared reflectance data

Summary form only given. The estimation of film thickness from measured reflectance data for silicon-on-insulator material is discussed. Kamins and Colinge (1986) have proposed a technique whereby the thickness of both the silicon surface layer and the insulator are determined. The method compares the positions of minima in the optical reflectance pattern measured in the visible, to minima obtained by computer simulations of the reflectance curves. Although this method yields good results, it requires either a large amount of computer time or a nomograph for each different insulator thickness. A new technique which employs the frequency content of the transformed reflectance versus inverse wavelength data is presented. There is a significant reduction in the computation burden compared to the above mentioned method