Determination of thickness and index of refraction of ZT (ZrO2+Ta2O5) thin film using Swanepoel method

Abstract

Thin films of ZT (ZrO₂+Ta₂O₅) have wide applications from antireflection (AR) coatings to optical filters. The index of refraction as a function of wavelength is important in the design of antireflection coatings. From the transmission spectrum of the thin film and by using Swanepoel method, the index of refraction as a function of wavelength and thickness were obtained. The transmission spectrum of ZT (ZrO₂+Ta₂O₅) thin film was measured using Red Tide USB650 spectrometer and U-4100 spectrophotometer. Calculated thicknesses of thin film were (7.1 ± 0.2) x 10² nm and (7.36 ± 0.08) x 10² nm for Red Tide USB650 spectrometer and U-4100 spectrophotometer, respectively.  Results have fractional error from 0.01-0.03 and are in good agreement with those reported in literature.