Improved Haacke's quality factor and paramagnetic-to-ferromagnetic transition realized in Ni co-doped CdO:Zn thin films

Cadmium oxide (CdO) is a promising transparent conducting oxide semiconductor whose optoelectronic and magnetic properties could be improved through doping. The role of synergetic effect between two metal dopants for enhanced optoelectronic and magnetic properties of CdO is not adequately studied. The mono-doping (Zn) and co-doping (Zn, Ni) effects on the optoelectronic and magnetic properties of CdO have been reported in this paper. Undoped, Zn-doped, and (Zn + Ni) co-doped CdO thin films have been deposited by spray technique using perfume atomizer. Crystallite size of pure CdO decreased from 35 to 29 nm with Zn doping and to 22 nm with (Zn + Ni) co-doping. Lattice parameter value of pure CdO decreased from 4.676 angstrom to 4.669 angstrom with Zn doping and with Ni co-doping it got reduced to 4.664 angstrom. Surface morphology improves with Zn and (Zn + Ni) co-doping. Better optical transparency and widened band gap values were realized for the Zn and (Zn + Ni) co-doped films. Oxygen-related peaks were observed in the PL spectra of all the films. Increased Haacke's quality factor was observed for the (Zn + Ni) co-doped CdO thin films. Paramagnetic-to-ferromagnetic transition has been realized for the co-doped films. The results obtained infer that the (Zn + Ni) co-doped CdO thin films are well suited for optoelectronic and spintronic device applications.