Abstract

The surface structure characterization our team has developed for several years (based on microdensitometer analysis of shadowed surface replicas) makes it possible to determine the statistical parameters which describe any microrough surface. In particular, it is easy to compute the power spectrum, which is a 1-D function. How the 2-D power spectrum which characterizes an isotropic rough surface can be computed from the 1-D one is shown here. Then, it is possible to compare—in the low spatial frequency range—the results given by this method with those obtained by optical methods. We present the results we obtained for the 2-D power spectra connected with a large set of microrough silver thin films, the rms height of which varies from 10 to 80 Å. (These silver films were evaporated onto fluoride underlayers.) Results are compared with those obtained by FECO, scattering studies, etc. Moreover, the study of the optical reflectance of these silver films near the surface plasmon makes it possible to compute these 2-D power spectra in another way and to compare their numerical values with the previous results.

© 1989 Optical Society of America