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  • 1 National Center for Radiation Research and Technology Nasr City, Cairo Egypt
  • 2 Ain Shams University Physics Department, Faculty of Science Cairo Egypt
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Abstract  

In comparison with other chalcogenide glassy systems, less attention has been paid to the quasi-ternary (quaternary) system As2(S, Se, Te)3. In this paper, thermal methods were used to characterize ten different quaternary homogenous semiconductor glasses that were prepared by mixing the stoichiometric binary systems As2S3, As2Se3 and As2Te3. The ratios of the constituent binaries in the quasi-ternary glasses exerted a great influence on their thermal spectrum. The samples poor in As2Te3 showed neither the exothermic nor the endothermic peak due to crystallízation (Tc) and melting (Tm), respectively, but only the glass transition (Tg). Three transition temperatures,Tg, Tc andTm, were detected for other compositions. On the other hand, a phase separation was observed in the samples rich in As2Te3. A cyclic scanning technique was used to investigate the thermally-induced phases during two consecutive heat ing-cooling cycles covering the temperature rangeTg−Tm. The energy of decompositionEd decreased on increase of the ratio As2S3/As2Se3 (at constant As2Te3), whereas it increased on increase of the ratio As2Te3/As2Se3 (at constant As2Se3 or As2S3).