Ablation characteristics of aluminum oxide and nitride ceramics during femtosecond laser micromachining

摘要

Femtosecond laser ablation of aluminum oxide (Al_2O_3) and aluminum nitride (A1N) ceramics was performed under normal atmospheric conditions (λ = 785 nm, τ_p = 185 fs, repetition rate = 1 kHz), and threshold laser fluencies for single- and multi-pulse ablation were determined. The ablation characteristics of the two ceramics showed similar trends except for surface morphologies, which revealed virtually no melting in Al_2O_3 but clear evidence of melting for A1N. Based on subsequent X-ray photoelectron spectroscopy (XPS) analyses, the chemistry of these ceramics appeared to remain the same before and after femtosecond laser ablation.