Density-functional supercell calculations are employed to follow the location of the donor levels arising from interstitial carbon and interstitial carbon-oxygen complexes in SiGe alloys. We show that these complexes interact weakly with neighboring Ge atoms, and that energetics rules out the existence of defect-Ge complexes involving direct Ge-C or Ge-O bonds. The C iOi defect is predicted to produce a hole trap that varies as E(0/+) - Ev = 0.41 - 0.76x eV, implying its disappearance for Ge fractions x greater than 0.5.
|Number of pages||3|
|Journal||Materials Science and Engineering B: Solid-State Materials for Advanced Technology|
|Issue number||SPEC. ISS.|
|Publication status||Published - 15 Dec 2004|
- Carbon-oxygen complexes
- Interstitial carbon
- SiGe alloys