Ellipsometry Techniques and Their Application to Oxide Film Growth on Aluminum.

摘要

The results of ellipsometric measurements on 2024-T-3clad aluminum surfaces subjected to various etching treatments are presented. Measurements on the 'bare'aluminum substrate indicate the complex refractive index is 1.14 (1-i4.06). Oxide film growth on the substrate shows the ellipsometric parameter delta decreases linearly as the film grows to 300A. It is observed that the variation of the ellipsometric parameter psi with small changes in the absorption coefficient of the film is much larger than the variation in delta. The general results of this study reveal that in most cases an average oxide film thickness can be determined,but surface inhomogeneity due to the etching solution can lead to incorrect interpretation of oxide film thickness if ground rules for matching observed to calculated data are not established. (Author)