Oxygen-Assisted Photoinduced Structural Transformation in Amorphous Ge-S Films

Authors

Yoshifumi Sakaguchi, Japan Atomic Energy Agency (JAEA)Follow
Dmitri A. Tenne, Boise State UniversityFollow
Maria I. Mitkova, Boise State UniversityFollow

Document Type

Article

Publication Date

8-1-2009

Abstract

We report our results of continuous illumination of Ge₄₆S₅₄ chalcogenide glass films with bandgap light in air. The outcome of this process is the formation of Ge–S backbone depleted in germanium. We relate this to consumption of some of the germanium available in the initial material due to the occurrence of a photoinduced oxidation. This is proved using energy dispersion spectroscopy which shows the presence of 17.68 at.% oxygen in the glass post-radiation. Raman spectra demonstrate that the initial material shows breathing modes, characteristic for Ge₄₆S₅₄ glass. After prolonged illumination Raman spectra reveal structure characteristic for the composition of the Ge–S backbone close to Ge₃₃S₆₇. The oxide forms a film on the surface and this changes the surface relief, studied by atomic force microscopy, but the oxidation is not surface-limited. The oxidation process in these glasses is discussed and the higher priority of germanium oxidation compared to the oxidation of sulphur is stated.

Publication Information

Sakaguchi, Yoshifumi; Tenne, Dmitri A.; and Mitkova, Maria I.. (2009). "Oxygen-Assisted Photoinduced Structural Transformation in Amorphous Ge-S Films". Physica Status Solidi (B), 246(8), 1813-1819. http://dx.doi.org/10.1002/pssb.200982009