Effective modelling of silicon nanowire solar cells

In this paper, the 3D finite difference time domain method (FDTD) has been used to investigate the effects of the surface roughness of the silicon nanowires (SiNWs) on their optical characteristics for solar cell applications. The ultimate efficiency (η) is used as a figure of merit to measure the absorption capabilities of the SiNWs. The numerical results show that the absorption of the SiNWs with surface roughness is higher than their smoothed cylindrical counterpart. This enhancement is attributed to the surface roughness which allows multiple scattering between nanowire sides. Therefore, the light trapping and the absorption through SiNWs are enhanced.