Resist Exposure

Laser direct imaging (LDI) of photosensitive resist

For the structuring and/or production of PCB circuits the board is first coated with a photo sensitive resist by dry film lamination or a lacquer.  With negative resists the laser exposed area is applying.  In the case of positive resists the areas exposed to UV light are disintegrated. These areas can be washed away by an aqueous-alkaline solution.  The exposure process is followed by developing and etching.  The very finest structures can be imaged by means of laser beam.  Apart from the ability to produce the finest structures the possibility of correcting distortion, shrinkage or positional errors caused by the preceding process steps is a substantial advantage.