Optimal design and fabrication of multilayer antireflection coating for III-V quadruple-junction solar cells

Optimal solution for the multilayers AR coating of 4J solar cell including design and fabrication was investigated. The real layer structure of 4J solar cell was determined first through reverse fitting, then the multilayers AR coating could be designed on the complete 4J solar cell to find the global optimization. After clarifying that the performance of multilayers AR coating is affected by oxidation of AlInP, the oxide layer was characterized and compensated to improve the spectrum. Through transmission electron microscopy (TEM), the oxidation depth was determined to be 5nm. Finally, the multilayers AR coating was re-optimized by considering oxidation layer into 4J solar cell. Using ion assisted deposition, the multilayers AR coating was fabricated with a slightly increased weight average reflectance of only 0.5%.