Ball grid array package for enhanced stress tolerance

摘要

The thermomechanical stress sensitivity of ball grid array (BGA) solder connections is significantly reduced, when the solder connections solidify in column-like contours after the reflow process-a result achieved by using the solder material in tapered openings of a thick sheet-like elastic polymer adhered to the BGA substrate and selected for its characteristics of non-wettability to solder and volumetric shrinkage greater than solder.