10.3% efficient Cu(In, Ga)Se2 solar cells fabricated by selenization of Cu-In-Ga precursors

In this letter, Cu-In-Ga precursor films are fabricated by one-step direct current (DC) sputtering of single ternary alloy target. After the post-selenization by rapid thermal processing (RTP), chalcopyrite-type Cu (In, Ga)Se-2 absorber layers in pure phase are obtained. Energy dispersive X-ray spectroscopy (EDS) results reveals that the Cu(In, Ga)Se-2 absorber layer is in a Cu-poor stoichiometry. Standard soda lime glass (SLG)/Mo/CIGS/CdS/i-ZnO/ITO/Ag grid structural solar cells are fabricated. A highest conversion efficiency of 10.33% with a V-oc 450 mV, a J(sc), of 37.5 mA/cm(2) and a FF of 61.3% without antireflection coating has been achieved. Our results demonstrate the selenization of Cu-In-Ga precursors sputtered from a single ternary target is a promising strategy for developing high efficient Cu(ln, Ga)Se-2 thin film solar cells. (C) 2016 Elsevier B.V. All rights reserved.