A simple and low-cost technique for silicon nanowire arrays based solar cells

A new PSG doping process was developed using a sol-gel method with phosphorus pentoxide (P2O5) powder combined with a screen-printing technique for the fabrication of electrodes. This process was applied in silicon nanowire (SiNW) arrays based solar cells. The PSG-doped SiNW arrays were used as both the anti-reflectance layer and the n(+) emitter for the solar cells. The morphology and photoelectric characteristics of the SiNW array solar cells were measured by a scanning electron microscope (SEM), a UV/VIS/NIR spectrophotometer, a quantum efficiency measurement system and a solar cell simulator. It was found that the reflectivity (R-lambda), internal quantum efficiency (IQE), series resistance (R-s) and power conversion efficiency (PCE) were influenced by the aspect ratio and the density of the PSG-doped SiNW arrays. Results indicate that there is a competition phenomenon between the aspect ratio and the density. It was observed that certain aspect ratio (similar to 5.15) with appropriate density (similar to 34.5%) of PSG-doped straight-aligned SiNW arrays possessed better solar cell (similar to 10.15%) performance. The SiNW array solar cells showed potential for low cost and mass-production in commercial solar cells applications. (C) 2011 Elsevier B.V. All rights reserved.