Ponente
Descripción
Ferroelectric thin films exhibit various properties, such as piezoelectric, pyroelectric, high dielectric constant, and a photovoltaic effect. The effect of sintering temperature of BiFeO3 (BFO) thin films on structural, ferroelectric, and photo-response properties was evaluated. BiFeO3 thin films were deposited on glass and FTO substrates by a three-step sputtering technique with a duration of 10, 30 and 50 min of deposit time at 100 W and 40 ccm of Ar flux, using 2-inch diameter ceramic targets obtained via a modified solid-state route. The films were heat-treated at a temperature of 550 °C for 15, 30, 45, and 60 min. The thickness of the sintered films were BFO15 = 267.79 nm, BFO30 = 191.58 nm, BFO45 = 164.53 nm, and BFO60 = 157.25 nm. The ABO3 perovskite-like crystal structure of the thin films was determined by X-ray diffraction (XRD). The diffraction peaks are in good agreement with the crystallographic planes of BiFeO3 datasheet PDF#86-1518 with a hexagonal-phase perovskite-like structure. Rietveld analysis was carried out to quantify the secondary phase of Bi2O2.33, lattice constants and crystal size. The microstructure and grain size by scanning electron microscopy (SEM) ranging from 96.01 nm to 63.82 nm; the roughness was obtained by atomic force microscopy (AFM) and a ferroelectric behavior was observed using piezoresponse force microscopy (PFM) with applied voltages of ±9 V. The photo-response was evaluated by I-V graphs with dark and UV light illumination.
