Fabrication, characterization and simulation of 3-D inverse-opal photonic crystals using laser-assisted imprinting

Three-dimensional (3-D) photonic crystals were fabricated by laser-assisted imprinting of self-assembled silica particles into silicon substrates. The multilayer self-assembly of silica particles were formed on the silicon substrates using isothermal heating evaporation approach. A KrF excimer laser pulse with a wavelength of 248 nm and a duration of 23 ns was used to melt the silicon substrate surface, which infiltrated and solidified over the assembled silica particles. By removing the silica particles embedded in the silicon using hydrofluoric (HF) acid, inverse-opal photonic crystals were fabricated This technique is capable of fabricating structures with complete photonic bandgaps (PBG), and engineering the photonic bandgaps by flexibly varying the silica particle size.