An NMR investigation of H cluster configurations in a-Si:H
In this work the characteristics of hydrogen clusters in hot filament assisted CVD and conventional glow discharge a-Si:H films are discussed. Computer simulations of the observed free-induction decays of the {sup 1}H NMR signals indicate that the distribution of the nearest-neighbor distances between H atoms in the H clusters is quite narrow in hot filament assisted CVD a-Si:H whereas the distribution is larger in glow discharge a-Si:H. This is clear evidence of improved structural order in hot filament assisted CVD a-Si:H. The relaxed hydrogenated divacancy and multi-vacancy models reproduce the main features of the observed free-induction decay in hot-wire a-Si:H very well. Computer simulations of the multiple-quantum NMR spectra indicate that a relaxed hydrogenated divacancy configuration leads to good agreement with experimental observations in device quality glow discharge a-Si:H. Results of simulations based on other H cluster configurations are also discussed. These results provide restrictions on the possible models for H clusters in a-Si:H.
- Research Organization:
- Univ. of North Carolina, Chapel Hill, NC (US)
- Sponsoring Organization:
- National Science Foundation (NSF); National Renewable Energy Laboratory
- OSTI ID:
- 20085477
- Resource Relation:
- Conference: Amorphous and Microcrystalline Silicon Technology - 1997, San Francisco, CA (US), 03/31/1997--04/04/1997; Other Information: PBD: 1997; Related Information: In: Amorphous and microcrystalline silicon technology--1997. Materials Research Society symposium proceedings, Volume 467, by Wagner, S.; Hack, M.; Schiff, E.A.; Schropp, R.; Shimizu, I. [eds.], 999 pages.
- Country of Publication:
- United States
- Language:
- English
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