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Stability of Ge-related point defects and complexes in Ge-doped SiO_2

C. M. Carbonaro·V. Fiorentini·F. Bernardini
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Abstract

We analyze Ge-related defects in Ge-doped SiO_2 using first-principles density functional techniques. Ge is incorporated at the level of ~ 1 mol % and above. The growth conditions of Ge:SiO_2 naturally set up oxygen deficiency, with vacancy concentration increasing by a factor 10^5 over undoped SiO_2, and O vacancies binding strongly to Ge impurities. All the centers considered exhibit potentially EPR-active states, candidates for the identification of the Ge(n) centers. Substitutional Ge produces an apparent gap shrinking via its extrinsic levels.

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C. M. Carbonaro, V. Fiorentini, F. Bernardini. 2002-02-27. Stability of Ge-related point defects and complexes in Ge-doped SiO_2. https://doi.org/10.1103/physrevb.66.233201

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