High-quality hydrogenated intrinsic amorphous silicon oxide layers treated by H2 plasma used as the p/i buffer layers in hydrogenated amorphous silicon solar cells

The treatment of hydrogenated intrinsic amorphous silicon oxide (i-a-SiOx:H) films by H-2 plasma is found through Fourier transform infrared (FTIR) spectroscopy to significantly improve the quality of the layers, which is attributed to variation in the Si-H-n, bonding structure and an improvement of bonding order. Meanwhile, scanning electron microscopy (SEM) results indicate that the initial growth of a hydrogenated intrinsic amorphous silicon (i-a-Si:H) layer deposited on a treated i-a-SiOx:H film is also improved, which is beneficial to the performance of solar cells deposited on highly textured front electrodes. By inserting an i-a-SiOx:H film that is optimized in terms of H2 plasma treatment time as a p/i buffer layer in hydrogenated amorphous silicon (a-Si:H) solar cell, a significant increase in fill factor and open-circuit voltage are also observed. In this way, a high initial conversion efficiency of 11.3% can be achieved in a single-junction a-Si:H solar cell with an active layer thickness of 300 nm. (C) 2015 Elsevier B.V. All rights reserved.