Raman characterization of molecular bonding and phase homogeneity in thin optical films

Submicrometer dielectric films have been analyzed by Raman spectroscopic techniques with respect to phase composition and homogeneity. Residual film stress has also been evaluated from measured vibrational band shifts in sol-gel as well as sputter-deposited films using available data from bulk studies of the pressure dependence on Raman frequencies. Dynamic studies of temperature and laser-induced phase transformations have been performed in situ, suggesting the applicability of this technique for film analysis during deposition. The potential advantages and limitations associated with Raman characterization of thin dielectric films will be addressed in this review using examples from current research in this area. 22 refs., 9 figs