Investigation on the coating of high refractive index quarter-wavelength thick zirconium as a material layer for dielectric mirror / Noor Fariza Subari

Sol gel method for the preparation of Zr02 thin film using zirconium oxychloride as the starting precursor. Thin films were deposited using dip-coating method onto silicon wafer and glass substrate. The dip-coating rate was varied from lOmm/min to 40 mm/min to obtain the exact thickness of 71.5 nm as one-quarter wavelength. The surface morphology, crystalline structure, optical properties, thickness and refractive index of Zr02 thin film were investigated by using AFM, XRD, Uv-Vis, Surface Profiler and Prism Coupler measurement. The average surface roughness of Zr0>₂ thin film is about 2 nm respectively. The films present a tetragonal phase for annealing temperature 500°c. A large percent of transmission approximately 90% was present for fast dip-coating rate and very low dip-coating rate have percentage of transmission below 70%. At the dip-coating rate lOmm/min, the exact thickness of 72 nm was achieved. However, the crack formation of one layer of ZrC0₂ thin film was observed. Refractive index that characterize by prism coupler using wavelength, λ = 632nm give high refractive index for Zr0₂ (2.07 -2.15).