Phase evolution and surface analysis of electron beam evaporated calcium and yttria-stabilized zirconia thin films

The manuscript investigates the structural and morphological characteristics of thin films of calcium stabilized zirconia (CSZ, 16 mol % CaO), synthesized through electron beam deposition on silicon wafers, with a focus on the phase evolution during annealing at 800 °C. The study compares these properties with yttria stabilized zirconia (YSZ, 8 mol % Y₂O₃) thin films. Rutherford backscattering spectrometry validates film composition, with thicknesses of ∼315 nm for CSZ and ∼285 nm for YSZ. X-ray diffraction initially identifies an amorphous structure, transitioning to a cubic phase post-annealing, with average crystallite sizes of 18.07 nm for CSZ and 16.22 nm for YSZ, corroborated by Raman spectroscopy. The lattice parameters are determined using Rietveld refinement. Surface morphology is investigated through field emission scanning electron microscope and atomic force microscopy shows a reduction in surface roughness from 6.05 nm to 1.34 nm for CSZ and from 4.54 nm to 1.64 nm for YSZ post-annealing, indicating enhanced homogeneity. Elemental distribution analysis using energy dispersive X-ray spectroscopy confirms film uniformity. The study provides insights into the structural evolution and morphological characteristics of calcium stabilized zirconia thin films, particularly at the nanoscale level, offering valuable contributions to its industrial applicability.