A study of superstrate amorphous silicon thin film solar cells and modules on flexible BZO glass

Abstract

Flexible thin film silicon solar modules on heat-resistant transparent flexible substrates are promising to achieve high efficiency by a combination of high-quality silicon thin films and fully monolithic series integration. In this work, performance of superstrate hydrogenated amorphous silicon (a-Si:H) thin film solar cells and modules on flexible glass using boron-doped zinc oxide (BZO) front electrode have been investigated. Compared with conventional glass, BZO thin films on flexible glass exhibited mixed structure of large-sized pyramid and small-sized grain, preferential crystalline orientations of (100) and (110), relatively lower surface roughness and scattering ability. Accordingly, compared with conventional BZO glass, a-Si:H thin film solar cells on flexible BZO glass exhibited a relative increase in open-circuit voltage, fill factor, and efficiency of 2.0, 5.5, and 3.4%, respectively. Finally, ∼50 cm2 flexible a-Si:H thin film solar modules were prepared by fully monolithic series integration using laser scribing, and relatively higher efficiency was achieved by improving thin films uniformity.