PWB Interconnect Strategy Using a Full Build Electroless Copper Plating System:Part 2: Etch Characteristics Available to Purchase

This paper constitutes a follow‐up to earlier work published in Circuit World, Vol. 17, No. 4. The first paper studied the metallographic structures of two commercially available full build electroless copper foils. Part 2 reports the investigations carried out into the etching characteristics of these copper foils, chemically deposited from full build electroless copper baths designated high elongation (HE) and high strength (HS). It is shown that, although attention should be given to the choice of etchant for these copper foils, they do not exhibit an uncontrollable etch rate, as is often feared.