Self-consistent modeling of jet formation process in the nanosecond laser pulse regime

Laser induced forward transfer (LIFT) is a direct printing technique. Because of its high application potential, interest continues to increase. LIFT is routinely used in printing, spray generation and thermal-spike sputtering. Biological material such as cells and proteins have already been transferred successfully for the creation of biological microarrays. Recently, modeling has been used to explain parts of the ejection transfer process. No global modeling strategy is currently available. In this paper, a hydrodynamic code is utilized to model the jet formation process and estimate the constraints obeyed by the bioelements during the transfer. A self-consistent model that includes laser energy absorption, plasma formation via ablation, and hydrodynamic processes is proposed and confirmed with experimental results. Fundamental physical mechanisms via one-dimensional modeling are presented. Two-dimensional (2D) simplified solutions of the jet formation model equations are proposed. Predicted results of the model are jet existence and its velocity. The 2D simulation results are in good agreement with a simple model presented by a previous investigator.