Hydrogen diffusion in {ital a}-Si:H: Solution of the tracer equations including capture by exchange
- Department of Engineering Physics, Ecole Polytechnique de Montreal, Montreal, Quebec, Canada H3C-3A7 (Canada)
- National Renewable Energy Laboratory, Golden, Colorado 80401 (United States)
We propose a model of trap-controlled diffusion in which diffusing atoms can be captured either by trapping at an empty trap or by exchange with chemically identical trapped atoms of different isotope number. We solve the model`s equations describing tracer diffusion experiments, and compare the predictions in the cases of dominant exchange and of dominant trapping. Comparison with experiments in {ital a}-Si:H shows that exchange is the dominant capture mechanism in D tracer diffusion measurements. This allows us to understand the relatively short distance ({similar_to}200 A) D travels before trapping. It also reconciles the smoothness of the D tracer diffusion profiles at long times with the existance of deeply bound ({gt}2.0 eV) H in {ital a}-Si:H.
- Research Organization:
- National Renewable Energy Laboratory
- DOE Contract Number:
- AC36-83CH10093
- OSTI ID:
- 130712
- Journal Information:
- Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 19 Vol. 52; ISSN PRBMDO; ISSN 0163-1829
- Country of Publication:
- United States
- Language:
- English
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