Computational Analysis of Antireflection Coatings for Semiconductor Solar Cells

One of the prominent techniques towards the improvement of solar cell designs based on conventional semiconductor materials is the inclusion of antireflection layers into the solar cell architecture. This work, is a proof of concept study which analyzes the effect of different antireflection coating (ARC) materials and their varied thicknesses on the reflectance of planar solar cell designs. Firstly the importance and design considerations for optimal ARC configuration are reviewed followed by Finite Difference Time Domain numerical simulations to verify the accordance of the results with respect to mathematical formulation. The refractive index of the ARC, its thickness and maximum possible current density were identified as the main design considerations for solar cells with antireflection coatings. It was observed that for the ARC of a particular refractive index, choosing an optimal thickness where lowest reflectance and maximum power absorption is obtained is a very important parameter for improving the overall performance of the solar cell. Further, it was observed that the cell with a coating of MgF2 shows a weaker sensitivity to the random thickness variations which are common in the process industry, making MgF2 a desired single layer ARC coating for semiconductor solar cells.