TY - JOUR T1 - Effects of heavy alkali elements in Cu (In, Ga) Se2 solar cells with efficiencies up to 22.6% JF - physica status solidi (RRL)–Rapid Research Letters Y1 - 2016 A1 - Jackson, Philip A1 - Wuerz, Roland A1 - Hariskos, Dimitrios A1 - Lotter, Erwin A1 - Witte, Wolfram A1 - Powalla, Michael VL - 10 KW - jackson2016effects ER -