Optimization of the back contact for 1.43 m2 a-Si:H photovoltaic module products based on the indoor light soaking test

Abstract

We have investigated the optimization of the sputtered metal back contact coupled with the B-doped zinc oxide (ZnO:B) back reflector for 1.43m2 p–i–n type hydrogenated amorphous silicon (a-Si:H) single-junction photovoltaic modules. The module with the Al back contact leads to the high stabilized aperture-area efficiency (ηAPER) of 7.3% with the low light-induced degradation ratio of 12.6% despite low initial ηAPER of 8.3%. However, the insertion of Ag causes a severe light-induced degradation. Through the further optimization, the stabilized maximum power of 100.2W is achieved. This is corresponding to stabilized ηAPER of 7.4%, which is the highest value for the certified industrial products of 1.43m2 a-Si:H single-junction photovoltaic modules.