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Refractive indices of layers and optical simulations of Cu(In,Ga)Se₂ solar cells.

ABSTRACT: Cu(In,Ga)Se₂ based solar cells have reached efficiencies close to 23%. Further knowledge-driven improvements require accurate determination of the material properties. Here, we present refractive indices for all layers in Cu(In,Ga)Se₂ solar cells with high efficiency. The optical bandgap of Cu(In,Ga)Se₂ does not depend on the Cu content in the explored composition range, while the absorption coefficient value is primarily determined by the Cu content. An expression for the absorption spectrum is proposed, with Ga and Cu compositions as parameters. This set of parameters allows accurate device simulations to understand remaining absorption and carrier collection losses and develop strategies to improve performances.

SUBMITTER: Carron R

PROVIDER: S-EPMC5954485 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Refractive indices of layers and optical simulations of Cu(In,Ga)Se2 solar cells.

Carron Romain R Avancini Enrico E Feurer Thomas T Bissig Benjamin B Losio Paolo A PA Figi Renato R Schreiner Claudia C Bürki Melanie M Bourgeois Emilie E Remes Zdenek Z Nesladek Milos M Buecheler Stephan S Tiwari Ayodhya N AN

Science and technology of advanced materials 20180515 1

Cu(In,Ga)Se2 based solar cells have reached efficiencies close to 23%. Further knowledge-driven improvements require accurate determination of the material properties. Here, we present refractive indices for all layers in Cu(In,Ga)Se2 solar cells with high efficiency. The optical bandgap of Cu(In,Ga)Se2 does not depend on the Cu content in the explored composition range, while the absorption coefficient value is primarily determined by the Cu content. An expressi ...[more]

PMID: 29785230

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