Some insights into picosecond laser micromachining

Picosecond laser processing is a cold light source processing method. It has almost no heat-affected zone. Relatively speaking, the materials that can be processed have become very wide, and can even include some transparent materials in the visible light and near-infrared light regions. Picosecond laser is a kind of micro-processing method, usually used for micron-level processing needs, such as some ultra-fine holes and wire grooves. At the same time, it can avoid thermal damage to surrounding materials and have fewer burrs and carbonization on the processing edge. In simple terms, the purpose of micro-processing is to obtain fine and clean incisions with a minimum heat-affected zone (HAZ).

There are two basic mechanisms for using lasers to perform precision drilling (punching), scribing or cutting. In general, traditional applications rely mainly on infrared and visible light to adjust lasers, whose pulse widths are in the tens of nanoseconds range, to remove materials through photothermal effects (see the figure above). In this case, the focused laser beam is a confined, high-intensity heat source that rapidly heats the target material and eventually vaporizes it.