Title Effect of the burn-out step on the microstructure of the solution-processed Cu(In,Ga)$Se_{2}$ solar cells Author Batuk, Maria Buffiere, Marie Zaghi, Armin E. Lenaers, Nick Verbist, Christophe Khelifi, Samira Vleugels, Jef Meuris, Marc Hadermann, Joke Faculty/Department Faculty of Sciences. Physics Publication type article Publication 2015 Lausanne , 2015 Subject Physics Source (journal) Thin solid films: an international journal on the science and technology of thin and thick films. - Lausanne Volume/pages 583(2015) , p. 142-150 ISSN 0040-6090 ISI 000353812400024 Carrier E Target language English (eng) Full text (Publishers DOI) Affiliation University of Antwerp Abstract For the development of the photovoltaic industry cheap methods for the synthesis of Cu(In,Ga)Se-2 (CIGSe) based solar cells are required. In this work, CIGSe thin films were obtained by a solution-based method using oxygen-bearing derivatives. With the aimof improving the morphology of the printed CIGSe layers, we investigated two different annealing conditions of the precursor layer, consisting of (1) a direct selenization step (reference process), and (2) a pre-treatment thermal step prior to the selenization. We showed that the use of an Air/H2S burn-out step prior to the selenization step increases the CIGSe grain size and reduces the carbon content. However, it leads to the reduction of the solar cell efficiency from 4.5% in the reference sample down to 0.5% in the annealed sample. Detailed transmission electron microscopy analysis, including high angle annular dark field scanning transmission electron microscopy and energy dispersive X-ray mapping, was applied to characterize the microstructure of the film and to determine the relationship between microstructure and the solar cell performance. We demonstrated that the relatively low efficiency of the reference solar cells is related not only to the nanosize of the CIGSe grains and presence of the pores in the CIGSe layer, but also to the high amount of secondary phases, namely, In/Ga oxide (or hydroxide) amorphous matter, residuals of organicmatter (carbon), and copper sulfide that is formed at the CIGSe/MoSe2 interface. The annealing in H2S during the burn-out step leads to the formation of the copper sulfide at all grain boundaries and surfaces in the CIGSe layer, which results in the noticeably efficiency drop. (C) 2015 Elsevier B.V. All rights reserved. E-info http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000353812400024&DestLinkType=RelatedRecords&DestApp=ALL_WOS&UsrCustomerID=ef845e08c439e550330acc77c7d2d848 http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000353812400024&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=ef845e08c439e550330acc77c7d2d848 https://repository.uantwerpen.be/docman/iruaauth/7fff60/d47126009.pdf http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000353812400024&DestLinkType=CitingArticles&DestApp=ALL_WOS&UsrCustomerID=ef845e08c439e550330acc77c7d2d848 Handle