Optical and structural characteristics of electrodeposited Cd1-xZnxS nanostructured thin films

The structural and optical characteristics of Cd1-xZnxS (CdZnS) thin films grown by the electrodeposition method were investigated in the present paper. The crystalline structure of the grown CdZnS thin film was determined as cubic wurtzite due to observed diffraction peaks associated with (111) and (220) planes. Atomic compositional ratios of the constituent elements were obtained using energy dispersive spectroscopy and doping concentration of the Zn was found as 5% (x similar to 0.05). Scanning electron microscopy image of the studied thin film indicated that grown film is nanostructured. Raman spectra of CdS and CdZnS thin films were measured and it was seen that observed longitudinal optical modes for CdZnS present a blue-shift. Temperature-dependent band gap energy characteristics of the thin films were studied performing transmission experiments in the 10-300 K temperature range. The analyses of the recorded transmittance spectra showed that direct band gap energy of the films decreases from 2.56 eV (10 K) to 2.51 eV (300 K) with the increase of temperature. The band gap energy vs. temperature dependency was studied applying well-known Varshni optical model and various optical parameters of the films were reported according to the results of the applied model.

Automated summary

In this study, the structural and optical characteristics of Cd1-xZnxS (CdZnS) thin films grown by electrodeposition were investigated. The films exhibited a cubic wurtzite structure, with Zn doping concentration found to be 5%. Raman spectra showed a blue-shift for CdZnS, and temperature-dependent band gap energy decreased from 2.56 eV at 10 K to 2.51 eV at 300 K. The Varshni optical model was applied to study the dependency of band gap energy on temperature, and various optical parameters were reported based on the model results.