SPECTROSCOPIC ELLIPSOMETRY OF THIN COPPER-FILMS ON GLASS SUBSTRATES

The complex reflectance ratio, rho=R(p)/R(s), for p- and s-polarized l ights of copper island films with the mean mass thickness d(w) of 4 to 16 nm on glass substrates was measured in the visible region by means of in-situ ellipsometry. The observed wavelength dependence of rho wa s interpreted with the effective anisotropic continuous film model. Th e clear resonance peak of plasma oscillation in epsilon(x)'' was obser ved at E congruent-to 1.8 eV, which corresponded to the mean distance between the particles of 7.5 nm in the film of d(w)=4 nm. The estimate d particle radius r was smaller by a factor of 10(-1) or 10(-2) than t he island size directly observed by means of a scanning electron micro scope.