Impact of a RbF post-deposition treatment on the chemical structure of wide-gap CuIn0.1Ga0.9Se2 thin-film solar cell absorber surfaces
Abstract
A detailed characterization of the impact of a RbF post-deposition treatment (RbF-PDT) on the chemical structure of a wide-gap Cu(In, Ga)Se2 thin-film solar cell absorber surface with a high Ga/(Ga + In) (GGI) ratio of 0.9 is presented. Using synchrotron- and lab-based x-ray photoelectron spectroscopy, as well as x-ray-excited Auger electron spectroscopy, we observe distinct differences to RbF-PDT on absorber surfaces with the common GGI of ∼0.3. In particular, RbF-PDT reduces sodium and oxide content at the surface, while the copper concentration at the surface is not affected. We find no spectral evidence for the formation of a distinct Rb–In–Se surface layer. In addition, we observe that the GGI ratio at the surface is slightly decreased due to a reduction of the Ga and an increase in the In concentration, which may explain the observed improvement in the power conversion efficiency after the PDT (from 6.8% to 7.3%).
Article Details
Journal Info
Applied Physics Letters
American Institute of Physics
Authors (10)
Luisa Both
Institute for Chemical Technology and Polymer Chemistry (ITCP), Karlsruhe Institute of Technology (KIT) 1 , Kaiserstr. 12, 76131 Karlsruhe,
Dirk Hauschild
Institute for Photon Science and Synchrotron Radiation (IPS), Karlsruhe Institute of Technology (KIT), Kaiserstraße 12, 76131 Karlsruhe, Germany
Mary Blankenship
Institute for Chemical Technology and Polymer Chemistry (ITCP), Karlsruhe Institute of Technology (KIT) 1 , Kaiserstr. 12, 76131 Karlsruhe,
Ralph Steininger
Institute for Photon Science and Synchrotron Radiation (IPS), Karlsruhe Institute of Technology (KIT), Kaiserstraße 12, 76131 Karlsruhe, Germany
Wolfram Witte
Zentrum für Sonnenenergie- und Wasserstoff-Forschung Baden-Württemberg (ZSW) 4 , Meitnerstraße 1, 70563 Stuttgart,
Dimitrios Hariskos
Zentrum für Sonnenenergie- und Wasserstoff-Forschung Baden-Württemberg (ZSW) 4 , Meitnerstraße 1, 70563 Stuttgart,
Stefan Paetel
Zentrum für Sonnenenergie- und Wasserstoff-Forschung Baden-Württemberg (ZSW) 4 , Meitnerstraße 1, 70563 Stuttgart,
Michael Powalla
Zentrum für Sonnenenergie- und Wasserstoff-Forschung Baden-Württemberg (ZSW) 4 , Meitnerstraße 1, 70563 Stuttgart,
Clemens Heske
Institute for Photon Science and Synchrotron Radiation (IPS), Karlsruhe Institute of Technology (KIT), Kaiserstraße 12, 76131 Karlsruhe, Germany
Lothar Weinhardt
Institute for Photon Science and Synchrotron Radiation (IPS), Karlsruhe Institute of Technology (KIT), Kaiserstraße 12, 76131 Karlsruhe, Germany