Physical structural thermal and optical properties of ternary and quaternary chalcogenide glassy semiconductors

Abstract

This thesis reports the work on two chalcogenide systems viz ternary and quaternary chalcogenide glasses and their thin films Bulk samples of the chalcogenide glasses have been synthesized using melt quench technique Thin films of bulk samples have been deposited using thermal evaporation technique newlineIn ternary Ge Se Sb glasses the composition Ge19Se81xSbx has been expanded by replacing Se with Sb from 4 at percent to 20 at percent The physical structural thermal and optical properties for Ge19Se81xSbx x equal two 0 4 8 12 16 172 20 system have been investigated systematically Bonding arrangements of ternary system have been carried out using FarIR transmission spectroscopy Thermal stability and crystallization kinetics have been studied under nonisothermal conditions using differential thermal analysis for Sb alloyed GeSe system UVVisNIR spectrophotometer has been used for the study of Ge19Se81xSbx thin films for their optical parameters like refractive index absorption coefficient optical band gap etc newlineIn quaternary Ge Se Sb Te glasses composition Ge19ySe638Sb172Tey has been extended with the replacement of Ge with Te from 2 at percent to 10 at percent Impurity effects in chalcogenides have importance in the formation of glassy semiconductors These impurity atoms are supposed to satisfy all the valence requirements when they enter the glassy network newline