Femtosecond Laser Drilling of Copper: Modeling and Experiment Comparison

This study experimentally and theoretically investigated the ablation of copper by a femtosecond green laser pulse of wavelength 515 nm and pulse duration 300 fs. The copper was processed by a single laser pulse with fluences up to 789 J/cm2. A modified Drude-critical point (DCP) model that considers the temperature-dependent inter-band transition, a two-temperature model (TTM), two phase change models, and a phase explosion model were adopted to obtain the temperature-dependent properties and ablation depth. The simulated ablation depths by the proposed DCP-mod method were in better agreement with the experimental results than those by the conventional DCP model.