Electroplating equipment design considerations for copper microvia filling

Electrolytic copper microvia filling is an enabling technology, prominently used in today´s manufacture of advanced HDI and packaging substrate product. In the high volume mass production of copper filled microvias, a wide variety of electroplating equipment designs are available to the fabricator. In this article, various aspects of electroplating equipment design used in the mass production of copper filled microvias are discussed, including a comparison of continuous and batch systems, anode materials, solution delivery (convection), and copper replenishment. The impacts of these variables on microvia filling performance, plated through hole throwing power, surface distribution, trace profile and bath life are described.