The new shadow line for a perfect metallization of micro- and blind holes

Fifteen meters of automatic horizontal line for removing all the impurities from the holes, making them conductive through the graphite deposit. A process that improves depositing the copper electrolytic in the holes thanks to the 30% increase in the spreading speed of the galvanic copper. A process that ensures a perfect metalizing.

When drilling holes in the dielectric materials, the high temperature reached by the tools generates a residue of dissolved resin on the walls of the holes (smear). The first part of the new line removes this residue. Thus, within the line there is a homogeneous chemical process for the removal of any impurities present on the wall of the holes (de-smearing).
The second part of the line deposits a thin layer of graphite (pre-metalizing shadow) on the walls of the hole just treated, by means of a forced pump process.

The line allows for treating most types of PCBs (rigid, semi-flexible, HDI) made with different types of basic materials (standard FR4, medium and high TG, high CTI, Radio Frequency laminated). It permits a high level of productivity, bringing two exceptional advantages for each type of hole when compared to other metalizing processes:

• Perfectly uniform final metalizing of micro-holes and blind holes, because the process ensures a greater spreading speed for the copper which is subsequently given a galvanic finish.

• Increased reliability of multilayer electrical connections: the reduced graphite deposit requires a smaller micro-incision (less than 4 microns) and therefore a smaller retraction of the intermediate metal layers in the multilayer connections.