Bideposited thin-film retardation plates for use at deep UV wavelengths

The physical vapour deposition process of serial bideposition is used to fabricate inorganic retardation plates of LaF3, NdF3, Sc2O3 and SmF3. For a deposition angle of 70° the form-birefringent materials exhibit linear birefringence in the range 0.09–0.13 at wavelength 248 nm. The study shows that NdF3 and Sc2O3 are unsuitable for use at 193 nm, due to excessive absorptive loss, and that LaF3 is the preferred material.