Structural and electronic studies of a:Si Ge:H alloys
- Harvard Univ., Cambridge, MA (USA)
This report describes a research program to investigate hydrogenated amorphous silicon-germanium alloys (a-Sil-xGex:H) for solar-cell applications. Specifically, studies were carried out to determine why these low-band-gap alloys exhibit photo-electronic properties inferior to those of hydrogenated amorphous silicon (a-Si:H). Two contributors to this phenomenon were established: (1) An amorphous semiconductor of smaller band gap than a-Si:H, but possessing tails to the conduction band and valence band densities of states of the same extent as in a-Si:H, and also possessing at least the same density of defect-related states, was bound to have shorter electron and hole lifetimes. (2) The structure of alloy films (whether with smaller or larger band gaps than that of a a-Si:H), exhibited considerable inhomogeneity; this led to an even greater reduction in the quantum-efficiency mobility lifetime product. The extensive studies confirmed that a-Ge:H is much poorer than a-Si:H from a photoelectronic standpoint.
- Research Organization:
- Solar Energy Research Inst. (SERI), Golden, CO (United States); Harvard Univ., Cambridge, MA (USA)
- Sponsoring Organization:
- DOE/CE
- DOE Contract Number:
- AC02-83CH10093
- OSTI ID:
- 6956436
- Report Number(s):
- SERI/TP-211-3655; ON: DE90000313
- Country of Publication:
- United States
- Language:
- English
Similar Records
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Related Subjects
36 MATERIALS SCIENCE
GERMANIUM ALLOYS
ELECTRICAL PROPERTIES
PHOTOVOLTAIC CELLS
FABRICATION
SILICON ALLOYS
ACTIVATION ENERGY
AMORPHOUS STATE
DEPOSITION
GERMANIUM HYDRIDES
GLOW DISCHARGES
HYDROGEN
OPTICAL PROPERTIES
PROGRESS REPORT
SEMICONDUCTOR MATERIALS
SUBSTRATES
TEMPERATURE DEPENDENCE
ALLOYS
DIRECT ENERGY CONVERTERS
DOCUMENT TYPES
ELECTRIC DISCHARGES
ELEMENTS
ENERGY
GERMANIUM COMPOUNDS
HYDRIDES
HYDROGEN COMPOUNDS
MATERIALS
NONMETALS
PHOTOELECTRIC CELLS
PHYSICAL PROPERTIES
140501* - Solar Energy Conversion- Photovoltaic Conversion
360603 - Materials- Properties
360601 - Other Materials- Preparation & Manufacture