Study of negative side wall surface roughness by picosecond photonic impact microdeposition

Laser-induced forward transfer (LIFT) has been well studied for metals but for non-metals published work is scarce. With recent advance of picosecond laser, non-metal in the direction of photonic impact is giving more flexibility of deposition control, including the control of depositing position and the control of surface roughness of deposited structures. In view of producing microstructures in micromould demands high side wall surface quality that current LIFT or similar laser-assisted method could not achieve, this study introduces the control of size and shape of micropatches by adjusting the distance and environment of deposition using a picosecond laser beam. A new method is proposed to change the shape of each micropatch by using multiple photonic impacts rather than single impact to achieve high surface quality, which had never been reported. It enables production of microstructures where current single impact deposition methods have not yet been solved.