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Abstract

This paper studies the effects of pressurized underfill process during chip encapsulation process on a 10 by 10 ball-grid-array (BGA) orientation. Underfill encapsulation play an important role to improve the reliability of flip chip package, yet the conventional capillary underfill (CUF) encapsulation process is subjected to several drawbacks such as extended filling time, incomplete filling and voids formation. To avert this problems relating to fluid flow, pressurized underfill (PUF) is introduced. The filling time, pressure, velocity and flow front propagation are observed during the pressurized filling process. The findings show velocity and pressure buildup at the start of the filling. Moreover, racing effect can observed during the whole filling process due to forced flow.