| abstract |
In some embodiments, methods include drilling one or a plurality of PTHs with any industrial grade drill to fabricate holes with positive etch back, flooding the PTHs with a dilute solution of an acrylate monomer/oligomer containing an appropriate level of peroxide initiator, polymerizing the acrylate, and then rising the PTHs with the solvent used in the formulation of the acrylate material. In one embodiment, the printed circuit board may include a substrate comprising a plurality of metal layers separated by a plurality of insulating layers; a plurality of plated through holes formed in the substrate, each plated through hole comprising: recesses formed at each insulating layer, copper lands between the recesses, a polymer coating in each recess, and a metal layer lining the plated through hole. |