Sunlight harvesting in thin-film silicon solar cells using latticed Al₂O₃ anti-reflection coating, Ag disk NPs, and Ag back-reflector

Abstract

Solar energy is one of the renewable energy sources that has been made available to humans at no cost. Therefore, solar cells are a suitable alternative candidate for fossil fuels. Thin-film solar cells, despite being a cost-effective technology, have low efficiency. Therefore, in this research work, we provided a new architecture for a 200nm Si solar cell, in which a latticed Al2O3 ARC is used as an antireflection, and Ag disk shape nanoparticles are placed on the front surface of the active layer in the center of the lattices. Furthermore, an Ag film is used as a back-reflector in the rear surface of the cell. By this design, because of the forward light scattering and near-field enhancement plasmonic effect of the Ag disk, reducing the Fresnel reflection from the cell surface by latticed ARC, and recycling the unabsorbed transmitted photons by BRS, the short-circuit current density and the efficiency can be reached to 14.67 mA/cm2, and 7.11%, respectively. These parameters equal 3.94 mA/cm2, and 1.78% for the bare cell, respectively.