Tuning optical properties of thin films based on selenium tellurium

Abstract Glasses of (Se90Te10)95M5 (M = In, Sb, and S) are set by melt-quench procedure. The incorporated elements were selected as examples from basic metal, semimetal, and nonmetal groups, respectively. Films of these glasses were evaporated onto glass substrates. The nature of the films was affirmed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The amorphous nature of the prepared films was confirmed by XRD measurements. Absorption coefficient, α, and refractive index, n, were estimated for all (Se90Te10)95M5 (M = In, Sb, and S) films. It is found that the optical band gap Eg decreases in the basic metal and semimetal groups, whereas it increases in the nonmetal group. The optical constants were estimated according to the single-oscillator model. The estimated results confirmed that the modified samples can be employed in the optoelectronic applications.