Electron density of states at Ge/oxide interfaces due to formation

✍ Scribed by Jan Felix Binder; Peter Broqvist; Alfredo Pasquarello

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 567 KB
• Volume: 88
• Category: Article
• ISSN: 0167-9317
• DOI: 10.1016/j.mee.2010.09.006

✦ Synopsis

An atomistic model of substoichiometric germanium oxide is generated through ab initio molecular dynamics. The resulting structure shows a predominance of threefold coordinated Ge and O atoms. We also generate substoichiometric models through bond-switching Monte-Carlo simulations, which preserve the fourfold Ge and the twofold O coordinations. These differing structures are energetically competitive. Alignment of their electron densities of states to that of GeO 2 reveals that the band-gap reduction is similar for both structures, mainly occurring through a shift of the valence band edge.