The effects of a double layer anti-reflection coating for a buried contact solar cell application

Theoretical and experimental investigations were performed on a double layer anti-reflection (DLAR) coating of MgF2/CeO2. We investigated CeO2 films as an AR layer because they have a proper refractive index of 2.46 and demonstrate the same lattice constant as the Si substrate. An optimized DLAR coating showed a reflectance value as low as 1.87% over wavelengths ranging from 0.4 to 1.1 μm. Buried contact solar cells (BCSC) were investigated using the following structure: MgF2/CeO2/Ag/Cu/Ni grid/n+ emitter/p-type Si base/P+/Al. The BCSC efficiency under an illumination of 50 mW/cm2 measured as high as 19.9% when employing DLAR coatings. MgF2/CeO2 DLAR coatings on the BCSC cell contributed to an increase of the fill factor (from 71% to 75%) and the Jsc (from 19.8 mA/cm2 to 22.6 mA/cm2).