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Description
Barium Strontium Titanate is a perovskite material known for its tuneable optoelectronic properties. Its optical properties are influenced by many factors including dopant incorporation and processing history. In this research, copped – doped Ba0.375Sr0.675TiO3 thin films were prepared from a seven – month old precursor. The study aims to investigate the combined effects of Cu incorporation and precursor aging on optical properties. Films with Cu concentrations of 0.0%, 0.5%, 1.0%, and 1.5% were evaluated for its thickness as well as utilizes UV – Vis spectroscopy to obtain bandgap and Urbach energy estimation, and X – Ray diffraction to evaluate the crystal structure of the film. Whilst film thickness may be influenced by aging, non – monotonic pattern was visible for increasing copper dopant concentration. Fresh undoped film showed a thickness of ~1386 nm whereas fresh undoped film showed a thickness of 22.91 nm. Additionally, the aged undoped film exhibited a direct optical bandgap of ~3.57 eV, higher than the non – aged undoped film at ~2.89 eV. Altered bandgap suggests that precursor aging may modify the optical properties of films. XRD results suggests that the films are tetragonal with a lattice parameter of a = 3.454 Å and c = 3.701 Å.
