Improvement of multicrystalline silicon solar cell performance via chemical vapor etching method-based porous silicon nanostructures

In this paper, we report on the effect of chemical vapor etching-based porous silicon (PS) on the performance of multicrystalline silicon solar cells performed via deep n(+)/p junction-type structures. Chemical vapor etching of silicon leads to the formation of porous silicon (PS) nanostructures that dramatically decrease the surface reflectivity from 30% to about 8%, and increase the minority carrier diffusion lengths from 90 mu m to 170 mu m. As a result, the short-circuit current density was improved by more than 20% and the fill factor (FF) by about a 10%. An enhancement of the photovoltaic conversion energy efficiency of the solar cells from 7% to 10% was observed. This low-cost PS formation process can be applied in the photovoltaic cell technology as a standard procedure. (C) 2012 Elsevier Ltd. All rights reserved.