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 (Rλ), internal quantum efficiency (IQE), series resistance (Rs) 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 (∼5.15) with appropriate density (∼34.5%) of PSG-doped straight-aligned SiNW arrays possessed better solar cell (∼10.15%) performance. The SiNW array solar cells showed potential for low cost and mass-production in commercial solar cells applications.