Improved CIGS modules by KF post deposition treatment and reduced cell-to-module losses

Abstract

The significant gain in efficiency by a KF post deposition treatment (PDT) on small cells, observed by several groups, can be scaled to full size modules. This is shown here by a significant gain for full size modules with KF PDT and a module reaching 17.2% (aperture area efficiency, externally confirmed). Another important topic is reducing the cell-to-module losses. Two different methods are presented and compared, a metal grid on top of the TCO and an improved TCO (ZnO:B). A sub-module (300×275 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) reaching 17.6% efficiency and a mini-module (50×50 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) reaching 18.7% efficiency is presented and confirms the reduction of cell-to-module losses.