Computational Study on the Effect of the Pulse Length on Laser Ablation Processes

Laser assisted ablation technology is widely used for micro-fabrication of metal and semiconductor components in the electronic industry. The outcome of those processes strongly depends on several variables such as the used material and different laser parameters. For a better understanding of these processes a study on the effect of the pulse length based on multi-physical simulations was performed. The use of a complex model which extends original CFD-capabilities of OpenFOAM simulation software with multiple physics allows us to obtain detailed description of the phenomena taking place during the process. Special attention is paid to transient process characteristics including melt ejections and metal vapor dynamics as well as ablation depth and their dependency on the pulse length scales applied. The limitation of the model, especially at ultra short pulses, is analyzed and possible improvements are discussed. Apart from the computational investigation comparison of simulated results against available experimental data is finally provided.