Effect of Fe alloying on the structural, optical, electrical and magnetic properties of spray-deposited CuO thin films

Pure CuO and CuO:Fe (10%) thin films were spray deposited on glass, silicon and quartz substrates at 500 °C. XRD patterns confirmed a monoclinic structure with cubic CuFe2O4 impurities. Surface morphology smoothed out on doping with Fe. The direct and the indirect band gaps of pure CuO and CuO:Fe (10%) films estimated from the spectral transmittance data indicated blue and red shifts respectively. X-ray photoelectron spectroscopy revealed the charge states of the elements. The activation energy for conduction was reduced on doping with Fe as estimated from an Arrhenius plot of the temperature-dependent resistivity. The magnetization of the CuO:Fe (10%) films at 300 K showed a hysteresis behavior with large coercivity. The large variation in the coercivity of the films due to pinned-type magnetic behavior may be useful for multilayer switching device applications.