Inner copper layers are covered by drill residues, mainly consisting of polymers (epoxy resin, polyimid, and acrylic adhesive). These layers are reducing contact between inner layer copper surface and copper coating of hole after plating.
The Desmearing plasma systems provide fast cleaning of mechanically drilled holes and excellent teflon activation. The printed circuit boards are exposed to low pressure plasma, which reduces, oxidizes or etches, according to its composition. The plasma is obtained with the help of a high frequency field applied to the electrodes, which assure homogenous distribution of the plasma in the chamber.
Desmearing and etchback of multilayer PCBs, Flex-Rigid PCBs and Flexboards, as well as surface treatment of polyimide, epoxy and teflon films.