Open AccessA strong antireflective solar cell prepared by tapering silicon nanowires
Author(s) -
JinWoo Jung,
Zhongyi Guo,
Sang-Won Jee,
HanDon Um,
Kwang-Tae Park,
Jung-Ho Lee
Publication year - 2010
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.18.00a286
Subject(s) - tapering , anti reflective coating , materials science , wafer , optoelectronics , etching (microfabrication) , optics , nanowire , silicon , solar cell , refractive index , nanotechnology , coating , layer (electronics) , computer graphics (images) , physics , computer science
Vertically aligned silicon nanowires (SiNWs) were cost-effectively formed on a four-inch silicon wafer using a simple room temperature approach, i.e., metal-assisted electroless etching. Tapering the NWs by post-KOH dipping achieved separation of each NW from the bunched NW, resulting in a strong enhancement of broadband optical absorption. As electroless etching time increases, the optical crossover feature was observed in the tradeoff between enhanced light trapping (by graded-refractive index during initial tapering) and deteriorated reflectance (by decreasing the areal density of NWs during later tapering). Compared to the bunched SiNWs, tapered NW solar cells demonstrated superior photovoltaic characteristics, such as a short circuit current of 17.67 mA/cm² and a cell conversion efficiency of ~6.56% under 1.5 AM illumination.