J. Phys. Colloques
Volume 42, Numéro C4, Octobre 1981Proceedings of the Ninth International Conference on Amorphous and Liquid Semiconductors
|Page(s)||C4-931 - C4-934|
J. Phys. Colloques 42 (1981) C4-931-C4-934
HARDNESS AND THERMAL CONDUCTIVITY OF As-Se-Te CHALCOGENIDE GLASSESM.F. Kotkata and M.B. El-den
Physics Department, Faculty of Science, Ain Shams University, Cairo, Egypt.
The results of the Vickers Hardness (VH) and the thermal conductivity (K) of the As-Se-Te glasses containing : 28.5 - 50 at % As, 5 - 41.4 at % Se, and 0.0 - 57 at % Te are given. A trend in the variation of VH (room temperature) with composition has been observed. The difference in nature and concentration of the chemical bonds between the stoichiometric system, As2Se3-As2Te3, and the other two alloy systems, AsSe-AsTe and As2Se5-As2Te5, are used to explain the contrasting results. Below Tg (the glass transition temperature) the thermal conductivity of the glasses increase with temperature. Such increase is pronounced at some compositions. The compositional variation of K for the chalcogenide systems all exhibit a dip in the conductivity at equal proportions of Se and Te. The value of K (20C) of the AsSexTex glasses varies between 0.18 - 0.95/10-2/cal/cm.sec.deg. The electronic contribution of the thermal conduction in each system is stimulated with Te, whereas the main mechanism of heat transport is by phonons. So, the increase in K toward the composition ends is controlled by the number of scattering centres in the glass matrix.