Hysol FP4581 and FP4583 are liquid epoxy encapsulants for use as underfills for flip-chip devices. FP4581 is formulated high-lead, bumped large die flip-chip packages. Is said to have low coefficient of thermal expansion properties and improved toughness over previous materials; forms a rigid, low-stress seal on solder joints. Is said to be ideal for flip-chip devices that require improved crack and fracture resistance. Is compatible with most no-clean flux systems. FP4583 is for applications requiring a fine filler. Contains fillers less than or equal to 2 µm in diameter; is formulated for overmolded components.

Henkel Corp., www.henkel.com/electronics