Ultrashort pulse laser ablation of polycarbonate and polymethylmethacrylate

Ablation experiments with ultrashort laser pulses (pulse duration 150 fs, w avelength 800 nm) on polymers (PC, PMMA) relevant for biomedical technology have been performed in air. The lateral and vertical machining precision w as evaluated by optical, atomic force and scanning electron microscopy. The ablation threshold reaches values in the range of 0.5-2.5 J/cm(2) and depe nds significantly on the number of laser pulses applied to the same spot. T he hole diameters are influenced by the laser fluence and the number of las er pulses. The relation between the ablation threshold and the number of la ser pulses applied to the same spot is described in accordance with an incu bation model. (C) 2000 Elsevier Science B.V. All rights reserved.