Effect of 1 MeV electron irradiation on TiO_2/Al_2O_3/MgF_2 anti-reflective coating for GaInP/InGaAs/Ge triple junction solar cells

摘要

In this study, a high performance TiO2/Al2O3/MgF2 multilayer anti-reflective (AR) coating, with an average reflectivity of 6.36% in spectral range of 300-1800 nm, applied on GaInP/GaAs/Ge triple-junction solar cell was designed by Essential Macleod Program (EMP) software. Based on the simulation results, TiO2, Al2O3, MgF2 single layer and TiO2/Al2O3/MgF2 multilayer AR coating samples were grown by Electron Beam Evaporation (EBE) system for 1 MeV electron beam irradiation experiment. The overall reflectivity of TiO2/Al2O3/MgF2 multilayer AR coating is decreased with the increase of electron irradiation fluence due to the change of reflectivity of each AR layer caused by the refractive index changes. This result indicates that the TiO2/Al2O3/MgF2 multilayer AR coating can improve the triple junction solar cell radiation resistance by achieving favorable permeability in the broadband solar spectrum, especially in 750-900 nm region where the main degradation spectral window for triple junction solar cell.