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The glass transition and the crystallization kinetics of Zn10Se90 glass by differential thermal analysis (DTA) technique under non-isothermal conduction were studied. The effective activation energies of the glass transition and the crystallization have been evaluated on the basses of the Kissinger and Matusita et al. approximations. Kinetic parameters of the crystallization process are significantly influenced by the heating rate. We have compared the experimental DTA with the calculated data curves for Zn10Se90 system using the Johanson–Mehl–Avrami (JMA) and Sestak–Berggren SB(M,N) models. Simulation results indicated that the SB(M,N) model is more suitable for describing the crystallization kinetics for the studied composition. Furthermore, the crystalline phases of annealed Zn10Se90 were characterized by X-ray diffraction. The surface morphology of the annealed samples was examined using scanning electron microscopy.

Bulk of ZnxSe100−x (x=10, 20 and 40 at%) was prepared by the usual quench melt technique. Thin films of these compositions were prepared by thermal evaporation. Differential thermal analyses (DTA) on powder samples under non-isothermal conditions show that the glass transition temperature Tg increased and crystallization temperature Tp decreased with increasing Zn content. The average particle size of the crystalline ZnSe phase deduced from X-ray diffraction (XRD) patterns show a decrease with increasing Zn content. These results were confirmed with the results obtained by scanning electron microscopy (SEM). The optical properties of ZnxSe100−x have been studied at a wavelength range (300–900 nm), and it was found that the optical band gap (Eg) increases with increasing Zn concentration in the ZnxSe100−x system. The results can be interpreted on the basis of the chemical bond approach proposed by Bicermo and Ovshinsky. The value of the extinction coefficient (k) decreases with increasing wavelength and Zn content. On the other hand, the optical energy gap (Eg) decreased with increasing the annealing temperature for Zn10Se90 thin films. These results can be interpreted by the Davis and Motte model.