Ablation Threshold of Sapphire by Pulsed Green Laser in Nanosecond Regime

Abstract

To establish the green laser ablation process more accurately, a detailed knowledge of the exact value of ablation threshold is of great importance. Therefore, the presented paper has investigated the single pulse ablation threshold using four different methods, namely, fitting method via diameter square, fitting method via depth, micro-topography method and the one-dimensional heat conduction model. Through this research, the well-defined threshold in term of laser fluence (J/cm2) is obtained, and the comparison among different methods casts a light on the effective way to determine the ablation threshold. Also, the underlying laser-material interaction mechanism is analyzed.