A Study of Reversible γ-Induced Structural Transformations in Vitreous Ge_23.5Sb_11.8S_64.7 by High-Resolution X-ray Photoelectron Spectroscopy

Abstract

The structural origin of reversible gamma-induced effects in vitreous Ge(23.5)Sb(11.8)S(64.7) has been investigated by high-resolution X-ray photoelectron spectroscopy (XPS). The changes in valence band spectrum from gamma-irradiation suggest a decrease of sulfur lone pair electron concentration accompanied by changes in bonding states of S and Ge. The appearance of additional doublets in the core-level XPS spectra of Ge, Sb, and S atoms for gamma-irradiated sample is described by the formation of over- and under-coordinated charged defect pairs (Ge(3)(-)-S(3)(+)) as a result of radiation treatment. The results verify the switching of Ge-S covalent bonds into S-S bonds as the main microstructural mechanism for gamma-induced optical effects in this glass.

Short-range order evolution in S-rich Ge–S glasses by X-ray photoelectron spectroscopy

“…component (2p 3/2 ) at~161.7 eV can be attributed to S-S-S (in chain, ring or ring-like configurations), at~161.1 eV to Ge-S-S and at 160.6 eV to Ge-S-Ge structural fragments (the analyzed core level element is written in bold font). The obtained positions are in good agreement with those reported previously for various sulfur-containing glasses[15,16,23].…”

Extended free‐volume defects in chalcogenide glassy semiconductors induced by high‐energy γ‐irradiation

“…This result well correlates with recent study of γ-induced structural transformations in glassy Ge-Sb-S using high-resolution X-ray photoelectron spectroscopy, showing that only Ge 3 -defects appear in the structure of γ-irradiated samples [18].…”

Structure of SbxGe40-xSe60 glasses around 2.67 average coordination number

“…The Ge 4p electronic states of the atoms participating in Ge-Ge bonding should contribute to the peak around~3.0 eV [16,19], but it could be masked by the stronger Se 4p band. The next broad features in the range 6-16 eV correspond to the signal from Ge 4 s, Sb 5 s and Se 4 s electrons [8,16,19,20].…”