Optimization of multilayer antireflection coating for photovoltaic applications

• A general rigorous method of analysis optical property of antireflection coating (ARC) is presented.
• Angle of incidence, polarization, and wavelength dependence nature of refractive index is taken into account in analysis.
• Antireflection coating is optimized for photovoltaic applications using Differential Evolution algorithm.
• Solar spectrum and solar cell absorption characteristics are considered in the optimization calculations.
• The proposed method is used to design ARC for a silicon solar cell and a AlGaAs/GaAs/Ge multi-junction solar cell.

Multilayer antireflection coating (ARC) for photovoltaics is optimized using Differential Evolution (DE) algorithm. A general transfer-matrix based mathematical formulation is used for evaluating reflection spectra of the system. Exact and complete values of refractive indices are used in the analysis to provide higher accuracy of the results. The proposed optimization method takes into account the solar irradiance spectra, absorption characteristics of semiconductors and angle of incidence to maximize efficiency. This method is found to reduce the average reflectance for a wide range of angles of incidence. The proposed method is used to design ARC for silicon solar cell and a multi-junction AlGaAs/GaAs/Ge solar cell. Finally, comparative analysis of different ARC designs is provided in terms of corresponding solar cell characteristics.