Standards for Which the Ellipsometric Parameter psi Remains Insensitive to Variations in the Angle of Incidence

We examine the possibility of using two- and three-phase systems suitable as standards for which the ellipsometric parameter ? remains insensitive to variations in the angle of incidence. These standards avoid propagation of errors in the angle of incidence with respect to the measured standard ? value. Different materials (dielectrics, metals, and semiconductors), adequate for the above purpose, are considered in different structure combinations, and their optical response are analyzed.