EPJ Photovoltaics 7, 70303 (2016)
https://doi.org/10.1051/epjpv/2016001

Solution-processed In₂S₃ buffer layer for chalcopyrite thin film solar cells

¹ Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, 14109 Berlin, Germany
² Qatar Environment and Energy Research Institute and Hamad Bin Khalifa University, Education City, Doha, Qatar
³ Freie Universität Berlin, Fachbereich Physik, Arnimallee 14, 14195 Berlin, Germany

^a e-mail: lan.wang@helmholtz-berlin.de

Received: 4 December 2015
Accepted: 27 January 2016
Published online: 26 February 2016

Abstract

We report a route to deposit In₂S₃ thin films from air-stable, low-cost molecular precursor inks for Cd-free buffer layers in chalcopyrite-based thin film solar cells. Different precursor compositions and processing conditions were studied to define a reproducible and robust process. By adjusting the ink properties, this method can be applied in different printing and coating techniques. Here we report on two techniques, namely spin-coating and inkjet printing. Active area efficiencies of 12.8% and 12.2% have been achieved for In₂S₃-buffered solar cells respectively, matching the performance of CdS-buffered cells prepared with the same batch of absorbers.