Effects of epoxy molding compound composition on the warpage and popcorn resistance of PBGA

Moisture sensitivity performance and warpage are known to be the primary reliability limitations of plastic ball grid array (PBGA) packaging. This study investigates how epoxy molding compound composition affects the warpage and popcorn resistance of PBGA. By using experimental design, the filler content, hardener-to- epoxy equivalent ratio and stress release agent content are chosen to investigate the individual and mutual effects on warpage and popcorn resistance. By using the same die attach die size and substrate combinations, the best composition passes JEDEC level 3 moisture sensitivity test; the warpage is about 3mil. Results in this study demonstrate that the adhesion strength of epoxy molding compound to solder mask is the most critical factor for enhancing popcorn resistance.