An effect of La doping on physical properties of CdO films facilely tasted by spin coater for optoelectronic applications

Transparent conducive oxides (TCOs) are having emerging applications in optoelectronic technology. Hence, herein, we have designed and fabricated the cadmium oxide (CdO/FTO) TCO films with different concentrations of Lanthanum (La) through a facile spin coating technique. The crystal system and phase confirmation of fabricated films was analyzed by X-ray diffraction analysis. The values of D-200 are found in the range of 25-31 nm indicates nanostructured thin films fabrication. EDX/SEM mapping revealed the presence of La and its homogeneity in CdO film. Atomic force microscopy was carried out to investigate the effect of La doping on surface topography of CdO films. The average values of grain size were estimated in the range of 7.56-10.95 nm along with surface roughness in range of 15.25-17.56 for pure and La-doped CdO films. The optical transparency of films was noticed in range of 75-85% in the NIR region. Direct and indirect band gap values are found in the range of 2.55-2.8 eV and 2.0-2.4 eV, respectively. The dielectric constant, loss, refractive and absorption indices were also calculated. Moreover, the linear, nonlinear susceptibilities and refractive index values were estimated and found in the range of 0.1-3, 1 x 10(-12) to 1.6 x 10(-7)esu and 2 x 10(-12) to 1.28 x 10(-8)esu, correspondingly.