IR studies of impurities in chalcogenide glasses and thin films of the Ge-Sb-S-Te system

Chalcogenide glasses with composition GexSb40-xS50Te10 (x = 10, 20 and 27 at.%) were synthesized and thin films from these parent materials were evaporated onto glass substrates. The vibrational properties of the impurities in the powdered glasses and the corresponding films were studied by FTIR spectroscopy. Vibrational modes attributed to O-H hydroxyl groups, molecular H2O and carbon impurity atoms were detected in the IR spectra of powdered glasses, but were absent in the IR spectra of the films. Vibrational modes of oxygen atoms bonded to basic elements, such as Ge-O and Te-O bonds, were present in the IR spectra of both kinds of samples.