Fabrication and estimation of optical constants of hydrophobic Ta2O5 thin films

Abstract

Present study investigates the optical properties and film thickness estimation of tantalum oxide (Ta2O5) thin films of various thicknesses, deposited by physical evaporation technique. The optical constants and thickness of deposited films were estimated by using envelope method. The thickness value obtained from this method has been compared with in-situ (quartz crystal thickness monitor) as well as Ex-situ (Coherence Correlation Interferometry) thickness estimation techniques. Refractive index calculated by envelope method was also validated using Reflectometer. These thickness values were used for the estimation of other optical constants such as refractive index, absorption and extinction coefficients. Contact angle measurement studies are also performed on uncoated as well as Ta2O5 coated glass substrates, which indicate the hydrophobic nature of these films.