An in-depth investigation of physical properties of Nd doped CdS thin films for optoelectronic applications

Abstract

The different contents (0 wt.%, 1 wt.%, 3 wt.% and 5 wt.%) of Nd @CdS films were casted using spray pyrolysis deposition procedure. The preferential orientation of crystallites along (002) for all films was noted by XRD profiles. The mean crystalline size (Davg), strain (ɛavg) and dislocation density (δavg) have also been evaluated using XRD results and discussed. The spherical shape morphology of nanoscale particles of Nd@CdS films were analyzed by FE-SEM, exhibits the increased grain sizes with Nd doping concentration. The optical band gaps (2.4–2.36 eV) were found to be decreased with increasing Nd doping content upto (3 wt.%) and increased at 5 wt.% The PL profile displays a stout intensity peak observed at 532 nm and week emission band at 638 nm. The dielectric constant, loss and loss tangent of pristine and Nd@CdS thin films were investigated by dielectric measurements. The optimum values of non-linear refractive index 1.06 × 10−10, 4.41 × 10−11, 3.44 × 10−11 and 1.85 × 10−10 were observed for Nd content varies from pristine to 5 wt.% respectively. Furthermore, optimum non-linear susceptibility values 7.31 × 10−12, 1.079 × 10−12, 4.53 × 10−13 and 1.36 × 10−11 were observed for 0, 1, 3 and 5 wt.% of Nd contents respectively in CdS. Such type of characteristics of Nd doped CdS thin films can be useful for optical devices.