Light management on silicon utilizing localized surface plasmon resonance of electroless plated silver nanoparticles

In this paper, a time- and cost-effective method of fabricating a light management structure on the surface of planar silicon (Si) substrates is developed utilizing localized surface plasmon resonance (LSPR) of silver (Ag) nanoparticles (NPs). The Ag NPs are produced by an electroless plating method and then modified in hot water. The resulting randomly distributed Ag NPs can reduce the reflection of the Si surface in the entire visible spectrum. With the help of a MATLAB-based analytical model on Mie theory, the size distribution of Ag NPs for desired optical properties is determined, and the reflection of the best performance sample decreases by up to 24.8% at a wavelength of 371 nm. An atmospheric degradation study of the Ag NPs is also reported, which demonstrates that the LSPR response of unprotected Ag NPs is markedly impaired after 14 days, while the LSPR response of aluminum oxide (Al2O3) protected Ag NPs is unchanged even after 90 days. The Al2O3 coated sample also shows a strong reflection reduction, exhibiting a reflection of as low as 7.6% at a wavelength of 662 nm and a weighted average spectral reflectance (Rave) of 12.2%.