Ablation of submicron structures on metals and semiconductors by femtosecond UV-laser pulses

Ablation of submicron structures on nickel, aluminum, copper, chromium, gold, silicon and germanium is presented by short ultraviolet laser pulses (0.5 ps, 248 nm). Features like periodic line structures with a line-spacing below 400 nm, and holes with characteristic sizes well below 1 mu m are produced on the sample surface by single laser shot exposure. The structures are projection printed by a Schwarzschild-objective (N.A. = 0.4) in air environment. A comparison of the morphology of ablation sites of various materials with different pulse durations (100 fs-50 ps) is presented. The role of thermal diffusion effects is discussed.