Chemical order in Ge{sub x}As{sub y}Se{sub 1-x-y} glasses probed by high resolution X-ray photoelectron spectroscopy
- Laser Physics Centre, Research School of Physics and Engineering, Australian National University, Canberra, ACT 0200 (Australia)
- Department of Physics and Astronomy, Austin Peay State University, Clarksville, Tennessee 37043 (United States)
- Department of Materials Science and Engineering, Lehigh University, 5 East Packer Avenue, Bethlehem, Pennsylvania 18015-3195 (United States)
We have measured high-resolution x-ray photoelectron spectra of Ge{sub x}As{sub y}Se{sub 1-x-y} glasses with a mean coordination number (MCN) from 2.2 to 2.78. The valence band spectra showed that a number of Se–Se–Se trimers can be found in Se-rich samples, whilst multiband features induced by phase separation can be observed in extremely Se-poor samples. When the Ge, As, and Se 3d spectra were decomposed into several doublets, which correspond, respectively, to different chemical environments, the perfect AsSe{sub 3/2} pyramidal and GeSe{sub 4/2} tetrahedral structures in Se-rich samples gradually evolved into defect structures, including As–As and Ge–Ge homopolar bonds, with increasing Ge and As concentrations. Two transition-like features were found at MCN = 2.5 and 2.64–2.72 that correspond first to the disappearance of Se-chains in the glass network and, subsequently, destruction of the perfect GeSe{sub 4/2} tetrahedral structures, respectively.
- OSTI ID:
- 22277963
- Journal Information:
- Journal of Applied Physics, Vol. 115, Issue 8; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
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