A study on the refractive index of sol-gel Ba1-xGdxTiO3 thin films using spectroscopic ellipsometry

Ba1-xGdxTiO3 thin films have been fabricated at different Gd3+ ionic concentrations, film thicknesses, and annealing temperatures using the sol-gel method. The refractive index of on a silicon substrate is characterized Spectroscopic Ellipsometry (SE), where ellipsometry angles Ψ Δ are fitted very well with Cauchy dispersion model. results show that 632.8 nm decreases from 2.18 to 1.892 increase ratio, while it increases thickness temperature. This trend for variation explained based interatomic spacing density densification films. Using Wemple–Di Domenico (WDD) model shows energy temperature doping. relatively high samples supports possibility as AR coating solar cells.