Growth and charactarization of Bi2o3 thin film

In this thesis study, Bi2O3 thin films were grown under different deposition parameters onto the glass, silicon and indium tin oxide (ITO) by using radio frequency magnetron sputtering technique. Bi2O3 target was used as the source of bismuth oxide. Initially growths were done under 40 W, 80 W and 120 W power levels in order to investigate the power difference effect on deposition. Then growths were done between 8-24mTorr (every 4mTorr) working pressure levels in order to investigate the pressure difference effect on deposition. Finally growths were done under 8mTorr and 24mTorr working pressure, 15sccm and 45 sccm partial O2 pressure levels in order to investigate the partial O2 pressure difference effect on deposition. X-Ray Diffractometer (XRD), Energy Dispersive Spectroscopy (EDAX), Scanning Electron Microscope (SEM) and absorption measurement technique were used for investigation of structural, morphological and optic properties. XRD analyzes have shown that all films have had growth direction along the (111) fcc-Bi2O3 and (222) fcc-Bi2O3 structures. Monoclinic and tetragonal polymorphs were formed and the directions and intensity of XRD peaks were changed with growth parameters difference. SEM analyzes have shown that the surface morphology, homogeneity and intensity were changed and different structures were formed on surfaces with growth parameters difference. Optical analyzes have shown that the films have had 2,02 eV - 2,94 eV band gap and the band gap have decreased with the increase of working pressure. Films were annealed at 400°C atmosphere environment in order to investigate the annealing effect. XRD analysis of annealed films have shown that new polymorphs were formed and peak intensity were increased. Optical analyzes have shown that the band gaps of films were increased and the absorption results were improved. The experimental studies have shown that growth power, working pressure and substrate are very effective on the structural, optical and morphological properties of Bi2O3 thin films.