The optical constants of as-prepared and thermally annealed Ge10Sb30Se60thin films were determined. Effect of heat treatment on the structure and optical properties of Ge10Sb30Se60 thin films in the range between the glass transition and crystallization temperature have been investigated. The glass transition and crystallization temperature of the synthesized sample was measured by non- isothermal DSC measurements. The microstructure and optical properties of these films were characterized by UV-VIS spectrum, scanning electron microscope (SEM) and X-ray diffraction (XRD). The optical band gap for as-prepared and annealed films have been calculated using Taucs low from the optical transmission and reflection spectra. The results indicate that the optical band gap Eopt increases when the annealing temperature (Ta) is lower than the glass transition temperature (Tg), while decreases with further increase of Ta. The XRD studies show that the as-prepared film is amorphous in nature, but the crystalline improved with increasing the annealing temperature. Furthermore the particle size and crystalline increases while the dislocation and strains decreases with increasing the annealing temperature. Thermal annealing was found to be accompanied by structural effects, which in turn, lead to change in the optical constants. The obtained results were explained in terms of the Mott and Davis model for amorphous materials and amorphous to crystalline structure transformations.
M. Hafiz, M.; El-Kabany, N.; Mahfoz Kotb, H.; and M. Bakier, Y.
"Annealing Effects on Structural and Optical Properties of Ge10Sb30Se60 Thin Film,"
International Journal of Thin Film Science and Technology: Vol. 4
, Article 2.
Available at: https://digitalcommons.aaru.edu.jo/ijtfst/vol4/iss3/2