Reliability qualification of a demountable packaging technology

Demountable TAB (or DTAB) is a detachable, solderless, IC packaging technology based on using separable pressure contacts directly between the package and the substrate (e.g. PC board). Developmental reliability testing was used as a principal tool in the engineering of DTAB. Nevertheless, upon completion of the development effort, the technology was required to pass a formal qualification with pre-set sample sizes, strife conditions, and allowable failure rates. Because of the fundamental differences between DTAB and conventional packages, new approaches were required in the design of the tests and test protocols. The qualification vehicle was a 432-lead package containing a 14-mm sq. chip and a 48-mm sq. TAB frame, both designed specifically for the purpose. The qualification program consisted of two distinct batteries of tests, one for the package, and the other for the package-to-board contacts.<
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