Flexible, Monolithically Integrated Cu(In,Ga)Se2 Thin-Film Solar Modules

Abstract

AbstractCIGS (Cu(In,Ga)Se2) thin-film solar modules on glass substrates are currently on the verge of commercialization. Entirely new application areas could be accessed with CIGS modules fabricated on thin and flexible non-glass substrates. Additionally, the roll-to-roll manufacturing of such flexible CIGS modules promises to be a low-cost production method. Different external Na supply methods and a vacuum-deposited buffer were investigated in this contribution, a sample of the challenges we face when modifying the standard, industrial CIGS module production process to the particular requirements of flexible substrates. Both metal foil substrates and polymer films are considered. Our excellent best results of above 14 % for single cells on titanium, more than 11% on polyimide, and around 7 % for modules on both substrates indicate our progress in developing flexible CIGS.