Synthesis and characterization of nanocrystalline CdZnO thin films prepared by sol-gel dip-coating process

Nanocrystalline CdxZn1 − xO thin films with different Cd volume ratios in solution (x = 0, 0.25, 0.50, 0.75 and 1) have been deposited on glass substrate by sol-gel dip-coating method. The as-deposited films were subjected to drying and annealing temperatures of 275 °C and 450 °C in air, respectively. The prepared films were characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, UV–vis spectroscopy and dc-electrical measurements. The results show that the samples are polycrystalline and the crystallinity of the films enhanced with x. The average grain size is in the range of 20–53 nm. The atomic percent of Cd:Zn was found to be 9.50:1.04, 6.20:3.77 and 4.42:6.61 for x = 0.75, 0.50 and 0.25, respectively. It was observed that the transmittance and the band gap decreased as x increased. All the films exhibit n-type electrical conductivity. The resistivity (ρ) and mobility (μ) are in the range of 3.3 × 102 − 3.4 × 10− 3 Ω cm, and 1.5 − 45 cm2 V− 1 s− 1 respectively. The electron density lies between 1.26 × 1016 and 0.2 × 1020 cm− 3.