POST ANNEALING EFFECT ON STRUCTURAL AND OPTICAL PROPERTIES OF (α-Fe2O3) THIN FILMS PREPARED BY SPRAY PYROLYSIS WITH MOVING NOZZLE

摘要

Hematite iron oxide (α-Fe2O3) thin films were prepared using spray pyrolysis with moving nozzle. Effects of 0-3 hours post heat treatment at 550°C on their structural and optical properties have been studied. XRD analyses avowed the formation of hematite thin films structure along (104) and (110) as preferred orientations and intensities of which change with post annealing whereas the grain size was varied in 40-48 nm upon time heat treatment. SEM images showed that all sample having uniform morphology with variant shape upon post annealing time. The transparency of hematite thin films was averaged around 65% in the visible region, with an direct band gap in the range 2.11-2.13eV. FTIR study affirms the abundance of Fe-O bond in all samples. Results indicate that the best time of post-annealing was 2 hours.