Plastics

Plastics play a key role in electronics. Printed circuit boards - whether rigid, flexible or a combination of both - are the basis of electronic devices. They are usually made of glass-fiber-reinforced epoxies (FR3, FR4, FR5) or flexible polyimide films. However, adhesive films or thermally conductive films are also becoming increasingly important in terms of overall assembly costs as well as thermal management. Many manufacturing processes reach their limits in plastics processing: The elasticity, insulating effect and low thermal stability of the materials make micro-machining especially difficult.

POM, PMMA, PVC
Polyimide (PI)
Adhesive foils
Heat conducting foils

Flex and rigid printed circuit boards are cut with the laser without leaving any residue. In laser depaneling, the individual PCBs are separated from the overall panel. The advantages of laser processing are clean cut edges without burrs or dust, which protects the PCB from contamination. In addition, laser processing is fast, precise and contact-free. This makes it possible to realize complex geometries with the finest contours as well as smooth, vertical cut edges. Post-processing becomes superfluous.

If thin foils are to be processed cleanly, without distortion and burr-free, USP lasers are the solution in plastics processing. The thermal influence in the material is very low and also prevents delamination of the material composites. Even different material thicknesses and combinations can be cut with the laser in just one operation.

Furthermore, the laser is used for through-hole plating of the printed circuit boards, i.e., the insertion of so-called connection holes (vias, microvias, blind vias). The laser process guarantees a very good hole quality with a high throughput at the same time. Depending on the material and the requirements for the hole size and geometry, (pulsed) UV, CO2 lasers or even hybrid processes are used here and the process parameters, such as pulse duration and pulse frequency, are adapted accordingly.

Likewise, damage-free identification/marking is possible by laser marking. Due to the ever-increasing packaging densities with simultaneous miniaturization, the possible area for marking on PCBs is decreasing. Pulsed fiber lasers in the green (532 nm) and blue (450 nm) wavelength range enable very small spot diameters and remove the solder resist down to the underlying copper layer, so that even the smallest code sizes are no problem. In the same way, solder joints can be exposed and adhesive surfaces can be cleaned by laser to enable high adhesion of the adhesive.