Plastic Land Grid Array (PLGA) Module and Printed Wiring Board (PWB) With Enhanced Contact Metallurgy Construction

An enhanced contact metallurgy construction for plastic land grid array (PLGA) modules and printed wiring boards (PWBs). The PWB may, for example, have subcomposite laminate construction and/or a double-sided LGA site. A plurality of preform contacts are each respectively soldered to one of a plurality of metal pads on a PLGA module carrier and/or a PWB. Each of the preform contacts comprises a metal preform base (e.g., copper, nickel) soldered to one of the plurality of metal pads and an electrolytic noble metal plating (e.g., gold) over the metal preform base. An electrolytic non-noble metal underplating (e.g., nickel) may be interposed between the metal preform base and the electrolytic noble metal plating. In one embodiment, the electrolytic non-noble metal underplating is 80-400 microinches thick to provide an enhanced diffusion barrier, and the electrolytic noble metal plating is 30-60 microinches thick and incorporates one or more hardening agents to provide enhanced wear and corrosion resistance.