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ARTICLE

Fabrication and characterization of Se₆₆S_44-xAs_x thin films chalcogenide

D. M. A. Latiff, B. A. Ahmed, S. M. Ali, K. A. Jasim^*

Department of Physics, College of Education for Pure Sciences ibn Al-Haitham, University of Baghdad, Iraq

* Corresponding Author:

Chalcogenide Letters 2025, 22(6), 521-528. https://doi.org/10.15251/CL.2025.226.521

Received 25 March 2025; Accepted 10 June 2025;

Abstract

In this paper, the effect of sulfur substitution by arsenic on the structural, optical properties of thin films of the trivalent chalcogenide Se₆₆S_44-xAs_x at different concentrations (where x = 0, 8, 16, and 24 at %) was studied. Thin films with a thickness of (300±10 nm) were prepared using thermal evaporation of bulk samples. Structural examinations were performed using XRD and AFM techniques. All the studied film samples were amorphous in structure and the intensity of the crystalline parts was high in the range of 10-40. Also, in Atomic Force Microscopy (AFM). It was found that increasing the concentration of arsenic affects the structural parameters such as surface roughness, particle density, and average grain size. As the arsenic element increased by 0.24, the grains became more regular, and the particle density increased. UV-Vis measurements reveal that the prepared films' absorption in the spectral wavelength range from 200 to 1100 nm. It was found that increasing the arsenic content led to a change in the absorbance of the films. The optical energy gap of Se₆₆S_44-xAs_x thin films was determined and it was found that increasing arsenic content affected the energy gap differently as it changed within the range (2.35-2.19 eV). The energy gap increased at concentrations of (8, 16%) while the energy gap decreased at concentrations of 24%.

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Keywords

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