Title :
Effect of filler settling of underfill encapsulant on reliability performance
Author :
Fan, Lianhua ; Zhang, Zhuqing ; Wong, C.P.
Author_Institution :
Packaging Res. Center, Georgia Inst. of Technol., Atlanta, GA, USA
Abstract :
Flip chip technology has been evolving for some time, and underfill material has contributed a lot to its development. By filling the gap between silicon die and organic substrate, the polymeric underfill can dramatically enhance the reliability of the flip-chip device, as it couples the solder interconnection with die and substrate. Underfill materials are normally composed of a polymerizable/curable organic matrix, such as the epoxy/anhydride system, normally pre-filled with inorganic filler, such as silica. Filler settling is very likely to happen for silica of a much higher density than that of the organic matrix at typical processing temperatures. Pre-filling the underfill with silica filler would modify the overall properties of the underfill material, and filler settling within underfill would also result in completely different local material properties. This paper investigates the corresponding effect of silica-pre-filling as well as the potential consequence of filler settling on the reliability performance of the flip chip device and solder joint fatigue life under thermal cycle/shock conditions
Keywords :
encapsulation; filled polymers; flip-chip devices; impurity distribution; integrated circuit interconnections; integrated circuit packaging; integrated circuit reliability; microassembling; soldering; thermal shock; thermal stress cracking; SiO2; epoxy/anhydride system; filler settling; flip chip device; flip chip technology; flip-chip device; gap-filling; inorganic filler; organic substrate; polymeric underfill; polymerizable/curable organic matrix; pre-filled organic matrix; processing temperatures; reliability; reliability performance; silica density; silica filler; silica-pre-filling; silicon die; solder interconnection; solder joint fatigue life; thermal cycle/shock conditions; underfill encapsulant; underfill material; underfill material properties; underfill materials; Active matrix organic light emitting diodes; Filling; Flip chip; Inorganic materials; Material properties; Organic materials; Polymers; Potential well; Silicon compounds; Temperature;
Conference_Titel :
Advanced Packaging Materials: Processes, Properties and Interfaces, 2001. Proceedings. International Symposium on
Conference_Location :
Braselton, GA
Print_ISBN :
0-930815-64-5
DOI :
10.1109/ISAOM.2001.916578
