Efficient Nanostructure Formation on Silicon Surfaces and in Indium Tin Oxide thin Films by sub-15 fs pulsed near-infrared Laser Light

High-repetition rate sub-15 fs pulsed near-infrared laser light facilitates production of self-assembled nanostructures on surfaces of crystalline silicon and in thin indium tin oxide films. Ripples at a periodicity of 130 - 140 nm as well as random nanopore arrangements were induced on Si(100) surfaces by scanning a high-numerical aperture focal spot in water across a predefined area. In indium tin oxide films periodic parallel cuts as well as single sub-20 nm cuts were generated at pulse energies less than 0.3 nJ. Nanowires of 150 - 300 nm in diameter were fabricated by laser annealing and subsequent hydrochloric acid etching.