DETERMINATION OF THE OPTICAL-CONSTANTS AND THICKNESS OF THIN-FILMS ONSLIGHTLY ABSORBING SUBSTRATES

A method for solving the optical constants of a thin film on a slightl y absorbing substrate is proposed. Using only a single-reflectance mea surement together with the interference fringes, one can calculate wit h good accuracy the thickness and the real and imaginary parts of the refractive index of the film. Besides its simplicity, this method also avoids the problem of multiple solutions. We show that this technique is effective in solving for the optical constants of thin films with weak or moderate absorption characteristics, and in particular we appl ied it to obtain the optical properties of amorphous C thin films on S i. (C) 1995 Optical Society of America