Ablation of polymer films by a femtosecond high-peak-power Ti:sapphire laser at 798 nm

Femtosecond infrared pulses from an ultrashort high-peak-power Ti:sapphire laser were successfully utilized for ablation of polymer films such as polytetrafluoroethylene, tetrafluoro- ethylene-hexafluoropropylene copolymer, and polyimide. Good agreement between experimental data and calculations from a model suggested that simultaneous absorption of three photons for polyimide and five photons for tetrafluoroethylene-hexafluoropropylene copolymer predominated over the other absorptive channels and that such a multiphoton absorption was induced efficiently.