Abstract

The optical constant evaluation technique for absorbing films has been newly developed. This technique can handle absorbing films, which are used for solar controlling films, with sufficient accuracy. In this technique, we assumed that the absorbing film has a double-layer structure. For example, a stainless steel film is assumed that consists of a metal layer and a surface oxidized layer, and this is supported by the surface analysis using SIMS. The advantage of this technique is that it can evaluate not only complex refractive indices but also thicknesses of metal (nitride) and surface oxidized layers. Another advantage is that only spectrophotometer and monochromatic ellipsometer measurements are necessary to calculate the optical constants in a wide range of wavelength. The optical constants of various film materials such as stainless steel, chromium, titanium nitride, silicon carbide, and so on were obtained using this technique. The errors are small enough so that optical properties of the multilayers for solar controlling films can be predicted with sufficient accuracy. For example, the spectral reflectance of a two-layer system (air/titanium nitride/stainless steel/glass) which was evaluated from those optical constants agreed well with measured values within a 3% error.

© 1988 Optical Society of America