Henkel Launches New Series of Underfills for Flip-Chip Applications

As flip chip technology proves its advantages not only for smaller footprint packages such as BGAs and CSPs but also for larger applications including ASICs and microprocessors, new materials will be required to meet the challenges associated with devices of varying sizes, a recent report by Henkel indicated.

To this end, Henkel has introduced two advanced liquid epoxy encapsulants designed for use as underfills for flip chip devices, Hysol FP4581 and Hysol FP4583.

“The electrical efficiency and higher density benefits of flip chip technology have been well proven for smaller footprint devices,” explains Dan Loskot, Director of Global Product Management, Liquids, for the electronics group of Henkel. “But, the inherent stress induced on larger die-–20mm and above--has made manufacturers of bigger devices a bit more cautious about the adoption of flip chip technology. Henkel says its new Amine-based underfill, Hysol FP4581 changes the game, though, delivering the reliability required while allowing these packages to benefit from the advantages of flip chip technology.”

In addition to the stress issues associated with flip chip applications, there have also historically been challenges with adhesion to Silicon Nitride (SiN), which is one of the most common die passivations employed by today’s packaging specialists. Older generation underfill systems had difficulty adhering to SiN, thus resulting in delamination and, ultimately, catastrophic device failure.

www.henkel.com/electronics