Physical mechanisms for picosecond laser ablation of silicon carbide at infrared and ultraviolet wavelengths

Investigations have been performed on the physical mechanisms of picosecond laser ablation of silicon carbide at 355 and 1064 nm, which have not been well understood yet. The study shows that the low-fluence ablation rates are close for 355 and 1064 nm, and the dominant material removal mechanism should be surface evaporation. At fluences above ∼2 J/cm2, the ablation rate increases very quickly for 355 nm, and the associated dominant mechanism is very likely to be critical point phase separation. For 1064 nm, the ablation rate variation with fluence above ∼2 J/cm2 follows the same trend as that for low fluences, and the mechanism should remain as surface evaporation.