Growth and Characterization of Iron Oxide Nanocrystalline Thin Films via Sol-Gel Dip Coating Method

In this paper, iron (III) oxide thin films are deposited on glass substrate via sol-gel dip coating by increasing withdrawal speeds in the range 100-250 mms^-1. Prepared thin films were characterized by UV-VIS spectrophotometer, spectroscopic ellipsometry (SE), X-ray diffraction (XRD), scanning electron microscope (SEM), vibrating sample magnetometer (VSM) and Fourier transform infrared (FTIR) spectroscopy. UV-VIS spectrum and SE show decrease in bandgap energy from 2.8 to 1.6 eV with increased withdrawal speed. FTIR results indicate formation of α-Fe₂O₃ (hematite) phase of iron oxide with preferred orientation along (104) plane. From SEM studies, it is observed that the developed α-Fe₂O₃ films are nanocrystalline with small grain size. The surface of α-Fe₂O₃ films is smooth and homogenous, which also supports the XRD results. VSM results show that α-Fe₂O₃ thin films have ferromagnetic behavior.