On Pulsed Laser Ablation of Metals: Comparing the Relative Importance of Thermal Diffusion in the Nanosecond - Femtosecond Regime

In recent years numerous reports on pulsed laser ablation of metals using various laser sources have fostered the discussion regarding the limitations due to thermal diffusion to produce feature sizes on (sub-)micron scale smaller than the diffusion length. Particularly in the light of novel micromachining applications, the relative benefits of using pulsed nanosecond (ns) lasers in the visible, such as copper vapour lasers and frequency doubled Nd:YAG, versus femtosecond (fs) Ti:Sapphire lasers operating in the infrared, remains debatable.