Inverse opal photonic crystal of chalcogenide glass by solution processing

Chalcogenide opal and inverse opal photonic crystals were successfully fabricated by low-cost and low-temperature solution-based process, which is well developed in polymer films processing. Highly ordered silica colloidal crystal films were successfully infilled with nano-colloidal solution of the high refractive index As30S70 chalcogenide glass by using spin-coating method. The silica/As-S opal film was etched in HE acid to dissolve the silica opal template and fabricate the inverse opal As-S photonic crystal. Both, the infilled silica/As-S opal film (Delta n similar to 0.84 near lambda = 770 nm) and the inverse opal As-S photonic structure (Delta n similar to 1.26 near lambda = 660 nm) had significantly enhanced reflectivity values and wider photonic bandgaps in comparison with the silica opal film template (Delta n similar to 0.434 near lambda = 600 nm). The key aspects of opal film preparation by spin-coating of nano-colloidal chalcogenide glass solution are discussed. The solution fabricated "inorganic polymer" opal and the inverse opal structures exceed photonic properties of silica or any organic polymer opal film. The fabricated photonic structures are proposed for designing novel flexible colloidal crystal laser devices, photonic waveguides and chemical sensors. (C) 2010 Elsevier Inc. All rights reserved.