Deposition parameters required for producing zirconia films for use in optical multilayer systems by electron-beam gun evaporation of zirconia and zirconium starting materials were investigated. The optical constants were determined as a function of distance, partial pressure of oxygen, and angle of incidence. The direct and reactive evaporation processes yielded ZrO2 films with refractive indices of 2.08 and 2.14, respectively, for vapor incident on the substrate at normal incidence.
J. A. Dobrowolski, P. D. Grant, R. Simpson, and A. J. Waldorf, "Investigation of the evaporation process conditions on the optical constants of zirconia films," Appl. Opt. 28, 3997-4005 (1989)