title: Broadband antireflective poly-Si nanosponge for thin film solar cells.
abstract: Antireflective nanosponges are fabricated on polycrystalline silicon (poly-Si) thin films using Ag-nanoparticles (NPs) assisted etching. Crystal orientations and grain sizes of the poly-Si thin films are investigated for the poly-Si nanosponge formation and the resultant optical properties. The Ag-NPs assisted etching preferentially etches the poly-Si thin films along crystal orientation of [110]. A 400 nm thick poly-Si nanosponge reduces effective optical reflection of the poly-Si thin film with substrate crystal orientation of (110) and averaged grain size of 250 nm from 26 % to 3 % at the wavelengths ranging from 400 nm to 1000 nm. Carrier lifetimes were found to be 41 and 36 mus for poly-Si thin film and RTO-passivated nanosponges, respectively.
authors.affiliation: Institute of Nanoengineering and Microsystems, National Tsing Hua University, Taiwan.
authors.forename: J Y
authors.initials: JY
authors.lastname: Chyan
authors.forename: W C
authors.initials: WC
authors.lastname: Hsu
authors.forename: J A
authors.initials: JA
authors.lastname: Yeh