Dynamics study of multiwavelength excitation process using F_2 and KrF excimer lasers

摘要

Ablation dynamics of fused silica by multiwavelength excitation process using F_2 and KrF excimer laser has been investigated by energy analyzed mass spectrometry of ablated species. The number of Si ion generated by multiwavelength excitation process corresponds to that by single-F_2 laser ablation and to approximately 2.1 times larger than that by single-KrF excimer laser ablation. In addition, kinetic energy distribution of Si~+ ablated by multiwavelength excitation process shows almost same as that by single-F_2 laser ablation. We regard that absorption of KrF excimer laser by excited state generated by F_2 laser (excited-state absorption: ESA) causes similar electron excitation process to single-F_2 laser irradiation, resulting in enhancement of Si ion with higher kinetic energy and then in high-quality ablation.