Ball grid array reliability assessment for aerospace applications

摘要

Reliability of ball grid arrays (BGAs) was evaluated with specail emphasis on space applications. This work was performed as part of a consortium led by the Jet Propulsion Laboratory (JPL) to help build the infrastructure necessary for implementing this technology. Nearly 200 test vehicles, each with four package types, were package type, board material, surface finish, solder volume, and environmental conditon. The packages used for this experiment were ocmmerically available packages with over 250 I/Os including both plastic and ceramic BGA packages. The test vehicles were subjected to thermal and dynamic environments represetnative of aerospace applications. Two different thermal cycling conditions were used, the JPL cycle ranged from-30degC to 100degC adn the Boeing cycle ranged from -55deg to 125degC. The test vehicles were monitored continuously to detect electrical failure and their failure mechanisms were characterized. They were removed perodically for optical inspection, scanning electron microscopy (SEM) evaluation, and cross-sectioning for crack propagation mapping. Data collected from both facilities were analyzed adn fitted to distributions using the Weibull distribution adn Coffin-Manson relationships for failure projection. This paper will describe experiment results as well as those analyses.