ON THE DETERMINATION OF REFRACTIVE INDEX AND THICKNESS OF THIN DIELECTRIC FILMS FROM MEASUREMENT OF TRANSMITTANCE

Refractive index and thickness of a transparent film (ZnS) on a transparent substrate (BK-7 glass) have been determined from measurement of normal incidence transmittance, using different methods. Some of the methods considered here are most widely used, as is apparent from the literature. The outcome of this study could help a researcher in selecting an appropriate method for such an application. The values of the refractive indices determined by different methods were found to be close to each other (within 0.5%). However, large (up to 4.4%) differences existed in the values of the thickness determined by different methods.