Optical absorption and photoelectrochemical performance enhancement in Si tube array for solar energy harvesting application

We studied large-scale fabrication and photovoltaic properties of Si tube array (SiTA) for solar energy harvesting application. The SiTA is fabricated with photolithography by using Poisson spot effect, followed by investigating its light absorption properties and photoelectrochemical performance to compare its solar energy harvesting property with the well studied Si hole and Si pillar array. It was found that SiTA has the highest onset potential and photocurrent among the three Si micro/nanostructures because of its hole-in-pillar hierarchal structures. The result suggests an alternative strategy in enhancing the efficiency of Si photovoltaic devices using this hierarchal structure. (C) 2013 AIP Publishing LLC [http://dx.doi.org/10.1063/1.4802997]