The photomodulation of the sub-bandgap optical absorption spectrum was measured for a series of amorphous hydrogenated silicon germanium (a-Si1-xGex:H) alloy specimens. For atomic germanium concentration exceeding 0.10 a single well-defined defect absorption band was observed which was associated with the germanium-related D-center found by electron spin resonance. The absorption peak was displaced by 0.4 eV from the optical gap as the gap varied from 1.65 to 1.0 eV.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Ceramics and Composites
- Condensed Matter Physics
- Materials Chemistry