Bunched Silicon Nanowires for Enhanced Light Trapping in Solar Cells

The enhancement in light trapping capabilities of bunched silicon nanowires were investigated using COMSOL Multiphysics. First, inclined nanowires (INWs) were optically modeled and their performance was compared with vertical nanowires (VNWs). An INW with a bend angle θ=7.6° generated more photocarriers inside the Si substrate in the wavelength range of 460nm to 680nm compared to its VNW counterpart. Also, in the INW array, a modulation in the electric field distribution in the substrate was observed. The study of the INW array leads to a deeper understanding of the effect of bunching on the performance of nanowire based solar cells.