Laser Ablation. Development and Application of Nanosecond Interferometry for the Clarification of Laser Ablation Dynamics.

Abstract

A nanosecond interferometric technique and its applications for the clarification of laser ablation dynamics are reviewed, and the morphological dynamics of the irradiated polymer films during or just after the excitation laser pulse is described. Since the nanosecond interferometric technique is based on the Michelson interferometer combined with a Q-switched Nd3+:YAG laser, expansion and contraction of the irradiated films about 20-30nm can be resolved with a time resolution of -10 ns. It is clarified that morphological dynamics of polymer films with different chemical and physical properties show a different morphological behavior depending on their chemical and physical properties upon laser ablation. On the basis of the revealed expansion and etching dynamics, ablation mechanism is discussed.