The effect of laser pulse length upon laser-induced forward transfer using a triazene polymer as a dynamic release layer

Abstract

Laser induced forward transfer (LIFT) is a laser direct write technique based on laser ablation. A UV-absorbing triazene polymer (TP) has been used as a sacrificial dynamic release layer (DRL) to propel other materials forward without damage. The effect of different laser pulse lengths (nanosecond and picosecond) on standard frontside TP ablation and backside TP ablation of aluminium thin films has been studied. Whilst the picosecond ablation causes the shock wave and the flyer to be faster, the ablation rate is considerably lower, suggesting an increase in ablation product energies and a decrease in loss mechanisms. The effect of beam energy homogeneity was seen to be an important factor for good flyer generation.