Fresnel calculations of double/multi-layer antireflection coatings on silicon substrates

Reflectance spectra calculations of double and multi-layer antireflection coating (ARC) structures based on Fresnel equations were studied in this work. A detailed explanation of Fresnel equations was presented with different polarization of incoming light for multi-layer antireflection coatings for solar cell applications. TiO₂/SiN_x, MgF₂/ZnS thin film stacks for double-layer ARC and SiO₂/Al₂O₃/TiO₂, MgF₂/SiO₂/TiO₂ thin film stacks for multi-layer ARC were studied. Transfer matrix method and PC1D simulation software were additionally used to simulate crystalline silicon solar cells with the considered double and multi-layer ARC films on their front surface with calculated thicknesses. The average reflectance (400-1100 nm) of the silicon surface calculated by Fresnel equations with triple-layer ARC was around 2.72%. Solar cell performances with each ARC structure were compared to evaluate the achieved output reflectance of the investigated thin films. Simulated short-circuit current density of solar cells with tri-layer ARC was 39.71 mA/cm², significantly higher than that of the ARC-free solar cells, resulting in an efficiency of 19.1%.