Structural, optical and room temperature ferromagnetic properties of Sn_(1_x)Fe_xO_2 thin films using flash evaporation technique

摘要

Iron doped tin oxide thin films (Sn_(1_x)Fe_xO_2) at x = 0.00, 0.03, 0.05, 0.07,0.10 and 0.15 were prepared onto Corning 7059 substrates using flash evaporation technique and studied the effect of iron (Fe) doping concentration on structural, optical and magnetic properties of the prepared thin films. From the X-ray diffraction patterns, it was found that the Sn_(1_x)Fe_xO_2 thin films were poly-crystalline with tetragonal structure. The crystallite sizes of the films were calculated using Scherrer's relation and found that it was about 25 nm. The chemical composition and oxidation states of the elements were found using energy dispersive analysis of X-rays and X-ray photo-electron spectroscopy. From this it was confirmed that the Fe was substituted Sn sites and is in Fe~(+3)states. The optical band gap of the films decreased from 3.98 to 3.76 eV with increase of Fe doping concentration. The pure SnO_2 thin films exhibited diamagnetism whereas Sn_(1_x)Fe_xO_2 thin films exhibited ferromagnetism at room temperature. A magnetic (M_s), coercivity (Hci) and retentivity (M_r) were found to be 13.062 emu/cm3, 114.98 G, 7.487 x 10~(-6) emu/cm3, respectively Sn_(1_x)Fe_xO_2 thin films at x = 0.07.