Absorption Enhancement in Thin-Film Silicon Solar Cell using Plasmonic Nanoparticles

Use of plasmonic nanoparticles for achieving enhanced light absorption in a thin-film silicon solar cell is a promising technique. We have designed a plasmon enhanced thin-film silicon solar cell with a periodic array of indium (In) nanoparticles and a thin silicon nitride (Si
₃
N
₄
) layer at the front surface. The indium (In) nanoparticles are embedded in the Si
₃
N
₄
layer which serves as an antireflective coating and increases the absorption of light in the thin silicon film of the cell. Improvement in light transmission through the front surface and light absorption enhancement in the cell are observed via numerical simulations in Finite Difference Time Domain (FDTD) method. Diameter of the spherical indium (In) nanoparticles and separation distance between adjacent nanoparticles are optimized for the best light trapping performance. Simulation results show that indium (In) nanoparticles of diameter 150 nm and having separation of 150 nm between adjacent nanoparticles provide overall better front surface light transmittance. An average of 39.88% light absorption enhancement is observed in the thin silicon film of the cell with the designed light trapping configuration over the wavelength range of 0.4-1.1 μm.