Transition metal Mn/Cu co-doped CdO transparent conductive films: Effect on structural, morphological and optical characteristics

Abstract

The transparent conducting un-doped, Cd0.99 Mn0.01O (Mn: 1.0%) and Mn/Cu co-doped CdO [(CuxMn0.01Cd0.99-x) (x: 0.005, 0.01 and 0.02 respectively)] films were prepared by successive ionic layer adsorption and reaction (SILAR) technique on soda lime glass substrates. The effect of Mn and Cu-dopant on structural, morphological and optical characteristics of the CdO films was analyzed by XRD, SEM, UV–Visible spectrophotometer and FT-IR spectroscopy. The XRD studies showed that the all-SILAR prepared films were polycrystalline and had preferential growth along the (111) directions. SEM analysis revealed that the Mn doping and Mn/Cu co-doping significantly influenced the surface morphologies of the CdO films. The EDX results confirmed that the dopant ions were incorporated properly into the CdO lattices. The optical band gap energy values of the all deposited films were determined by extrapolation method and observed to be in the range of 2.08–2.38 eV. Optical analysis results disclosed that doping alters the band gap facilitating the potential of transparent conductive films to be exploited in optoelectronic devices. Furthermore, FT-IR was used to confirm the existence of metal-doped CdO. The investigations showed that co-doping significantly affects the physical properties of SILAR-grown CdO films.