Dielectric Thin Films*

Abstract

The factors which influence the properties of dielectric films formed by thermal evaporation are discussed. Detailed results are given for several materials which are of practical importance. The results obtained for the refractive index of transparent films (a) by the Brewster angle method and (b) by the measurement of film reflectance are considered. It is concluded that differences observed in certain cases cannot be ascribed to the use of different methods of measurement. Some tentative comments are made on the connection between the observed mechanical stress and structure of films of ZnS, MgF2, cryolite, LiF, and CaF2.