As is sometimes the case, industry acceptance of an evolving packaging standard has preceded the "implementation technologies" necesitated by the new standard. BGA packaging is such a situation .While offering many clear advnatages, the BGA package yields several areas of trepidation, all of whihc grow in magnitude as the package size grows. The larger of the BGA packages, now numbering I/O counts in the 1000 to 2000 reange have frustrated many who have attempted to use them. Thses packages are difficult to reflow, expensive to inspect and all but impossible to rework. Traditionally, socketing solutions have helped bridge this gap. WIth BGA's however, these solutions have been slow in coming, as the package presents a very non traditional mating condition. The BGA solder ball is itself a poor point of contact for socketing, suited only to its intended purpose of being reflowed. It is inconsistent in shape, location, and hardness. It will cold flow over time against even the lowest of normal forces, and will fracture at the device if overly constrained or loaded.
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