Optical and dispersion studies of thin S35-xGe15SnxTe50 films: Assessment of some physical parameters of samples. (1st April 2023)

• Record Type: Journal Article
• Authors: Hassanien, Ahmed Saeed; Sharma, Ishu; Sharma, Pankaj
• Is Part Of: Physica scripta. Volume 98:Number 4(2023)
• Publication Date: 2023-04-01
• Subjects: glassy semiconductor -- amorphous thin films -- optical and physical properties -- refractive index dispersion -- nonlinear refractive index -- average heat of atomization; Physics -- Periodicals; 530.05
• DOI: 10.1088/1402-4896/acc2f9
• Languages: English
• ISSNs: 0031-8949

Abstract

Abstract: This article presents a study on the optical and dispersion characteristics of a group of thin films with exciting potential for optical applications. Thermally evaporated a-S35−x Ge15 Snx Te50 thin films (SGST) where x ranges from 0 to 10 at.% have been investigated. XRD, EDX, and FE-SEM techniques are utilized to examine the samples' physical properties. Meanwhile, optical characteristics are studied in the 300–2500 nm region through transmission and reflection measurements. Experimental and theoretical methods were employed to determine the optical bandgap energies (Eg ), indicating that the films' electronic transition is indirectly allowed. The Eg -values decreased as Sn-content increased, reaching a range of 1.031 eV to 1.301 eV, while the refractive index increased from 2.513 to 2.741. In addition, the Wemple-Di-Domenico model was used to determine the dispersion energies (Eo and Ed ), and it is found that they decreased as Sn-content increased, from 2.014 eV to 2.672 eV for Eo, and from 13.009 eV to 15.334 eV for Ed . Many other important parameters, such as the average heat of atomization, total mean bond energy, and deviation from stoichiometry, are also calculated and discussed. The results of this investigation suggest that these SGST samples could be used in various optical applications and provide a basis for further research and innovation in this exciting field.