Influence of laser energy on spectroacopic analysis and structural and optical properties of (CdTe)_1−x:Sn_x thin films

This study is a spectroscopic study to investigate the effects of pulse laser energy and target content of (CdTe)_1−x:Sn_x on plasma parameters during deposition of thin film and the correlation of these parameters with the properties of the prepared thin films. The plasma parameters, including electron temperature and electron number density, in addition to other related parameters, were investigated for plasma produced by the pulse laser at different pulse energies of 200, 300, 400, and 500 mJ, in addition to the Sn content in the (CdTe)_1−x:Sn_x target as 0.1, 0.25, and 0.5. The relations between pulse laser energy and emission intensities correspond to Sn and Cd atoms to predict the variation of Sn content in the prepared thin films with the laser energy and the Sn content in the target. It was found that the low pulse energy may sputter a lower amount of the Sn content compared to its content in the target. While increasing laser energy may result in sputtered target components at the same efficiency. Plasma parameters, including electron number density, electron temperature, Debye length, plasma frequency, and Debye number, appeared to be related to the pulse laser energy but slightly varied according to the Sn content. The X-ray diffraction, FE-SEM, shows distinct variations in the Sn content’s structural characteristics and surface morphology. The elemental analysis by the EDX spectroscopy indicates a lower tin ratio in the deposited thin films than the ratio in the targets. This study suggests a practical approach for altering the properties of the deposited thin films.