Evolution of local surface roughness in 193 nm ArF excimer laser ablation of ground Yb:YAG crystal

Abstract

The surface quality of YAG crystals plays a decisive role in the output performance of the device. In this investigation, it was found that the surface quality of Yb:YAG crystal was improved by 193 nm ArF excimer laser ablation. The influence of laser energy density and pulse numbers on the surface roughness of Yb:YAG crystal was obtained. The possible laser ablation mechanism of YAG crystal was analyzed by thermal conduction and photodissociation theory. Surface profile analyses reveal that photochemical ablation was the dominant mechanism of material removal.