The Development and use of a Modified Immersion Tin as a high performance solderable Finish

摘要

The inexorable trend of miniaturization continues ot challenge all the processes used in PWB fabricatioin. The need for an acceptable final finish, which meets or exceeds the exacting requirements of planarity, solderability, ionic cleanliness and surface insulation resistance, is no exception. The traditional HOt Air Soldr Leveled finish has long since reached its technological zenith and nw faces increasing competition form a variety fo alternative finishes. A range of technologies are now available, including those based on Nickel/Gold, Pallladium, Silver, and also a variety of Organic Solderability Preservatives. These options, in most cases, differ fundamentaly with respect ot their surface properties, methods, costs of application and, perhaps more importantly, their ultimate performance capabilities.