Modeling of Thermoelastic Stress Wave in Laser-Assisted Cell Direct Writing

Laser-assisted cell direct-write technique has been a promising biomaterial direct-write method. For safe and reproducible cell direct writing, the cell damage due to process-induced external stress must be understood in addition to biological property research. The objective of this study is to model the thermoelastic stress wave propagation inside the coating in laser-assisted cell direct writing when the vaporization or optical breakdown of coating materials is not available. It is found that a bipolar pressure pair has been developed within a finite thin coating medium, locations near the laser focal spot experience higher stresses, and shorter duration laser pulses lead to higher thermoelastic stresses. This study will help understand the photomechanical stress and its relevance with biomaterial damage in laser-assisted cell direct writing.