Laser ablation of nylon 6.4 under UV irradiation at 193 and 248 nm

We report on the ablative etching of Nylon 6.6 [-NH-(CH2)(6)-NH-CO-(CH2)(4)-CO-] at 193 nm and 248 nn, using a pulse discharged ArF and KrF excimer laser respectively. The etch rate at different fluences was determined for both wavelengths, along with other descriptive parameters such as the threshold fluence. The mass spectroscopic analysis showed that even at low laser energies there was a complete braking of the polymer chain bonds at both wavelengths. Moreover it seems that photofragments with two carbon atoms along with the C=O radical, have a higher probability to be ablated, while photofragments with three carbon atoms appear only under irradiation at 248 nm. No significant photofragments beyond 50 amu were recorded at both laser wavelengths.