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Carrier drift-mobilities and solar cell models for amorphous and nanocrystalline silicon

Published online by Cambridge University Press:  31 January 2011

Eric A Schiff
Eric A Schiff*
Affiliation:
easchiff@syr.edu, Syracuse University, Physics, 201 Physics Building, Syracuse, New York, 13244-1130, United States, 315-443-3901
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Abstract

Hole drift mobilities in hydrogenated amorphous silicon (a-Si:H) and nanocrystalline silicon (nc-Si:H) are in the range of 10-3 to 1 cm2/Vs at room-temperature. These low drift mobilities establish corresponding hole mobility limits to the power generation and useful thicknesses of the solar cells. The properties of as-deposited a-Si:H nip solar cells are close to their hole mobility limit, but the corresponding limit has not been examined for nc-Si:H solar cells. We explore the predictions for nc-Si:H solar cells based on parameters and values estimated from hole drift-mobility and related measurements. The indicate that the hole mobility limit for nc-Si:H cells corresponds to an optimum intrinsic-layer thickness of 2-3 μm, whereas the best nc-Si:H solar cells (10% conversion efficiency) have thicknesses around 2 μm.

Keywords

amorphousoptoelectronicSi
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 1153: Symposium A – Amorphous and Polycrystalline Thin Film Silicon Science and Technology–2009 , 2009 , 1153-A15-01
Copyright
Copyright © Materials Research Society 2009

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