• Becker, C.; Wyss, P.; Eisenhauer, D.; Probst, J.; Preidel, V.; Hammerschmidt, M.; Burger, S.: 5 x 5 cm2 silicon photonic crystal slabs on glass and plastic foil revealing broadband absorption and high-intensity near-fields. Scientific Reports 4 (2014), p. 5886/1-7

10.1038/srep05886
Open Access Version

Abstract:
Crystalline silicon photonic crystal slabs are widely used in various photonics applications. So far, the commercial success of such structures is still limited owed to the lack of cost-effective fabrication processes enabling large nanopatterned areas (>> 1 cm2). We present a simple method for producing crystalline silicon nanohole arrays of up to 5 x 5 cm2 size with lattice pitches between 600 and 1000 nm on glass and flexible plastic substrates. Exclusively up-scalable, fast fabrication processes are applied such as nanoimprint-lithography and silicon evaporation. The broadband light trapping efficiency of the arrays is among the best values reported for large-area experimental crystalline silicon nanostructures. Further, measured photonic crystal resonance modes are in good accordance with light scattering simulations predicting strong near-field intensity enhancements greater than 500. Hence, the large-area silicon nanohole arrays might become a promising platform for ultrathin solar cells on lightweight substrates, high-sensitive optical biosensors, and nonlinear optics.