Investigation of Structural, Morphological, Optical, and Electro-optical Properties of PZT Thin Films Deposited by Custom-Made RF Magnetron Sputter

This study investigates the structural, morphological, optical, and electro-optical characteristics of Pb(Zr0.52Ti0.48)O3 (PZT) thinfilms deposited on fluorine-doped tin oxide (SnO2:F, FTO) substrates using a custom-made radio frequency (RF) magnetronsputtering system. The films were grown at a substrate temperature of 300 oC and subsequently annealed at 650 oC for 1 hourin a muffle furnace in an air ambient to promote crystallization and phase formation. XRD analysis confirms the formation ofpolycrystalline perovskite PZT with a preferred (110) orientation, average lattice constant of 4.09 Å, and average crystallite size of37.06 nm. SEM analysis reveals a homogeneous granular surface morphology with grain sizes ranging from 95 to 105 nm, whileEDS analysis verifies a Zr/Ti atomic ratio of 51.9/48.1, closely matching the morphotropic phase boundary (MPB) composition ofthe PZT in the target. Optical transmittance measurements show approximately 80% transmittance in the visible region, and Tauc’splot analysis yields a direct bandgap of 3.35 eV for the annealed film, representing a significant blue shift compared to the 2.66eV bandgap of the as-deposited film. The transient photocurrent measurements carried out under the Hg-Xe light excitation revealan increase from picoampere level (dark) to 17 nA (illuminated), with rise and fall times of ∼ 130 ms. The results demonstratethat RF magnetron sputtering combined with appropriate thermal treatment produces high-quality PZT thin films, which can besuitable for ultraviolet (UV) optoelectronic applications.