Laser Application of Polymers - Original PDF
نویسندگان: Thomas Lippert
خلاصه: Abstract Laser ablation of polymers has been studied with designed materials to evaluate
the mechanism of ablation and the role of photochemically active groups on the ablation
process, and to test possible applications of laser ablation and designed polymers. The incorporation of photochemically active groups lowers the threshold of ablation and allows
high-quality structuring without contamination and modification of the remaining surface.
The decomposition of the active chromophore takes place during the excitation pulse of the
laser and gaseous products are ejected with supersonic velocity. Time-of-flight mass spectrometry reveals that a metastable species is among the products, suggesting that excited
electronic states are involved in the ablation process. Experiments with a reference material,
i.e., polyimide, for which a photothermal ablation mechanism has been suggested, exhibited pronounced differences. These results strongly suggest that, in case of designed polymers
which contain photochemically active groups, a photochemical part in the ablation mechanism cannot be neglected. Various potential applications for laser ablation and the special
photopolymers were evaluated and it became clear that the potential of laser ablation and
specially designed material is in the field of microstructuring. Laser ablation can be used to
fabricate three-dimensional elements, e.g., microoptical elements