Laser processing of flexible substrates

The paper describes some results of a research project aimed at the application of CO₂ and frequency multiplied Nd:YAG lasers for drilling via holes into copper clad flexible laminates of polyimide and polyester based materials. We have also carried out experiments for removing the insulation layer from the copper foil to open windows, i.e. to obtain clean copper areas. This can be a key process in the production of TABs. Three wavelengths (10600 nm, 1064 nm and 355 nm) were used to find the optimal process parameters for drilling and layer removing. The samples were examined and evaluated many ways to conclude the general behaviour of the material and its interaction with different laser beams.