Morphology and Band Gap Controlled Studies of CdSxSe1−x Films Deposited by Laser Ablation

Abstract

Through the utilization of the pulsed laser ablation technique, binary and ternary CdS_xSe_1-x films, with a value of 0 ≤ x ≤ 1, were deposited on a quartz substrate. The formation of these films was accomplished by employing a pulsed Nd:YAG laser, maintaining a pressure of 4 × 10^-6 Torr within the growth chamber, and maintaining a substrate temperature of 550 ºC. The hexagonal structure of the CdS_xSe_1-x semiconducting films was validated by XRD, which indicated that the films possessed a preferential orientation in the (002) plane. This orientation was associated with the films’ exceptional crystal quality. The energy band gap (E_g) can be estimated with the help of transmittance spectra. The values that we have calculated for the ternaries are 1.78, 1.9, and 2.06 eV, whereas the values for CdSe are 1.68 eV and the values for CdS are 2.39 eV. All of the samples exhibited a robust luminescence emission when the temperature was at room temperature. Furthermore, Raman spectroscopy revealed that the phonons associated with LO-CdS and LO-CdSe were seen simultaneously in the compound of ternaries. There is a correlation between the content of sulfur and the changing intensities and positions of these peaks.