Dear Phil: As you indicated, the potential for circumferential voiding exists in any direct plating process that would remove the underlying copper from the conductive deposit. This condition is commonly referred to as wedge voiding, as it exhibits itself as a wedge shaped defect in cross sectional examinations. Further, this condition manifests itself typically on the oxide treated surface of the foil only. Actual production using palladium based direct plating systems can occasionally exhibit this defect, but the liklihood is not very great. Further, because palladium systems can modify the process sequence to incorporate microetching prior to conditioning, the chance of the defect occuring is further reduced. Finally, substituting double treat foil for oxide treated foil will eliminate the chance of wedge voiding in all but the most severe cases. Kevin H. Baranowski Atotech USA Inc.