Glass formation, density, microhardness, and optical properties of As–Si–Te chalcogenide alloys (original) (raw)

1999, Journal of Non-Crystalline Solids

The As±Si±Te glasses are IR transparent, have relatively high glass transition temperatures among the chalcogenide glasses, and thus have been considered suitable in high temperature IR-optical applications. Sixty one As±Si±Te alloys of various compositions were prepared, and their glass formation, glass transition temperatures, density, microhardness, and IR transmittance were experimentally determined. By quenching the As±Si±Te melt in air, glasses can be formed in the As±Si±Te system. Some of the as-quenched alloys are completely amorphous, and some are partially amorphous and partially crystalline. Most notably, some As±Si±Te alloys exhibit volatility. Although the As±Si±Te glasses have good IR transmittance, the oxygen impurities in the glasses cause IR absorption at the wave numbers of 690 cm À1 and 960 cm À1 . Their glass transition temperature (T g ) decrease with Te contents, and the highest T g found in this study is at 394°C for the As 0X2 Si 0X4 Te 0X4 . The densities of As±Si±Te alloys increase with higher silicon content. The microhardness of As±Si±Te alloys is relatively high among chalcogenide glasses and its value increases with increasing silicon content. Ó 0022-3093/99/$ -see front matter Ó 1999 Elsevier Science B.V. All rights reserved. PII: S 0 0 2 2 -3 0 9 3 ( 9 9 ) 0 0 4 1 3 -5