Black silicon solar cells with interdigitated back-contacts achieve 22.1% efficiency

The nanostructuring of silicon surfaces—known as black silicon—is a promising approach to eliminate front-surface reflection in photovoltaic devices without the need for a conventional antireflection coating. This might lead to both an increase in efficiency and a reduction in the manufacturing cost...

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Detalles Bibliográficos
Autores: Savin, Hele, Repo, Päivikki, von Gastrow, Guillaume, Ortega Villasclaras, Pablo Rafael|||0000-0001-6577-614X, Calle, Eric, Garin Escriva, Moises|||0000-0003-1309-7457, Alcubilla González, Ramón|||0000-0003-4827-4513
Tipo de recurso: artículo
Fecha de publicación:2015
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/81173
Acceso en línea:https://hdl.handle.net/2117/81173
https://dx.doi.org/10.1038/NNANO.2015.89
Access Level:acceso abierto
Palabra clave:Solar cells
Photovoltaic power generation
Nanowires
Cèl·lules solars
Energia solar fotovoltaica
Àrees temàtiques de la UPC::Energies::Energia solar fotovoltaica::Cèl·lules solars
Àrees temàtiques de la UPC::Energies::Energia solar fotovoltaica
Descripción
Sumario:The nanostructuring of silicon surfaces—known as black silicon—is a promising approach to eliminate front-surface reflection in photovoltaic devices without the need for a conventional antireflection coating. This might lead to both an increase in efficiency and a reduction in the manufacturing costs of solar cells. However, all previous attempts to integrate black silicon into solar cells have resulted in cell efficiencies well below 20% due to the increased charge carrier recombination at the nanostructured surface. Here, we show that a conformal alumina film can solve the issue of surface recombination in black silicon solar cells by providing excellent chemical and electrical passivation. We demonstrate that efficiencies above 22% can be reached, even in thick interdigitated back-contacted cells, where carrier transport is very sensitive to front surface passivation. This means that the surface recombination issue has truly been solved and black silicon solar cells have real potential for industrial production. Furthermore, we show that the use of black silicon can result in a 3% increase in daily energy production when compared with a reference cell with the same efficiency, due to its better angular acceptance.