Mixed-phase p-type silicon oxide containing silicon nanocrystals and its role in thin-film silicon solar cells

Duncan Alexander, Christophe Ballif, Mathieu Gérard Boccard, Grégory Bugnon, Peter Cuony, Matthieu Despeisse, Michael Marending
American Institute of Physics, 2010
Article

Résumé

Lower absorption, lower refractive index, and tunable resistance are three advantages of amorphous silicon oxide containing nanocrystalline silicon grains nc-SiOx compared to microcrystalline silicon c-Si, when used as a p-type layer in c-Si thin-film solar cells. We show that p-nc-SiOx with its particular nanostructure increases c-Si cell efficiency by reducing reflection and parasitic absorption losses depending on the roughness of the front electrode. Furthermore, we demonstrate that the p-nc-SiOx reduces the detrimental effects of the roughness on the electrical characteristics, and significantly increases c-Si and Micromorph cell efficiency on substrates until now considered too rough for thin-film silicon solar cells.

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https://infoscience.epfl.ch/record/155060?ln=fr

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