@misc{BaerSongCaballeroetal., author = {B{\"a}r, Marcus and Song, X. and Caballero, R. and Duarte, Roberto Felix and Gerlach, Dominic and Kaufmann, Christian and Schock, Hans-Werner and Wilks, Regan G.}, title = {Na incorporation into Cu(In,Ga)Se2 thin-film solar cell absorbers deposited on polyimide: Impact on the chemical and electronic surface structure}, series = {Journal of Applied Physics}, volume = {111}, journal = {Journal of Applied Physics}, number = {3}, issn = {1089-7550}, pages = {034903}, abstract = {Na has deliberately been incorporated into Cu(In,Ga)Se2 ("CIGSe") chalcopyrite thin-film solar cell absorbers deposited on Mo-coated polyimide flexible substrates by adding differently thick layers of NaF in-between CIGSe absorber and Mo back contact. The impact of Na on the chemical and electronic surface structure of CIGSe absorbers with various Cu-contents deposited at comparatively low temperature (420 °C) has been studied using x-ray photoelectron and x-ray excited Auger electron spectroscopy. We observe a higher Nasurface content for the Cu-richer CIGSe samples and can distinguish between two different chemical Na environments, best described as selenide-like and oxidized Na species, respectively. Furthermore, we find a Cu-poor surface composition of the CIGSe samples independent of Na content and — for very high Na contents — indications for the formation of a (Cu,Na)-(In,Ga)-Se like compound. With increasing Nasurface content, also a shift of the photoemission lines to lower binding energies could be identified, which we interpret as a reduction of the downward band bending toward the CIGSe surface explained by the Na-induced elimination of InCu defects.}, language = {en} } @inproceedings{LipsSchulzeStarretal., author = {Lips, Klaus and Schulze, Tim F. and Starr, David E. and B{\"a}r, Marcus and Wilks, Regan G. and Fenske, F. and Ruske, Florian and Reiche, Martin and Krol, Roel van de and Reichardt, Gerd and Sch{\"a}fers, Franz and Hendel, Stefan and Follath, Rolf and Bahrdt, Johannes and Peredkov, Sergey and DeBeer, Serena and H{\"a}vecker, Michael and Knop-Gericke, Axel and Rau, Bj{\"o}rn and Kaufmann, Christian and Schlatmann, Rutger and Schl{\"o}gl, Robert and Rech, Bernd and Raoux, Simone}, title = {EMIL: The Energy Materials In-situ Laboratory Berlin - A novel characterization facility for photovoltaic and energy materials}, series = {31st European Photovoltaic Solar Energy Conference and Exhibition, proceedings of the international conference held in Hamburg, Germany, 14 -18 September 2015}, booktitle = {31st European Photovoltaic Solar Energy Conference and Exhibition, proceedings of the international conference held in Hamburg, Germany, 14 -18 September 2015}, publisher = {WIP}, address = {M{\"u}nchen}, isbn = {3-936338-39-6}, doi = {10.4229/EUPVSEC20152015-1AO.2.1}, pages = {25 -- 28}, language = {en} }