UV-nano-imprint lithography technique for the replication of back reflectors for n-i-p thin film silicon solar cells

Texturing of interfaces in thin film silicon solar cells is essential to enhance the produced photocurrent and thus the efficiencies. A UV nano-imprint-lithography (UV-NIL) replication process was developed to prepare substrates with textures that are suitable for the growth of n-i-p thin film silicon solar cells. Morphological and optical analyses were performed to assess the quality of the replicas. A comparison of single junction amorphous solar cells on the original structures and on their replicas on glass revealed good light trapping and excellent electrical properties on the replicated structures. A tandem amorphous silicon/amorphous silicon (a-Si/a-Si) cell deposited on a replica on plastic exhibits a stabilized efficiency of 8.1% and a high yield of 90% of good cells in laboratory conditions. It demonstrates the possibility to obtain appropriate structure on low cost plastic substrate. Copyright (C) 2010 John Wiley & Sons, Ltd.