Authored By:
Bob Wettermann, MIT
BEST Inc.
Rolling Meadows, IL, USA
Summary
As BGA component package dimensions continue to get thinner as more of them are being used in handheld device applications. End use device requirements include the need to maintain their interconnections, even when dropped, thus necessitating the use of underfill. The increased demand for higher board densities requires neighboring or mirrored devices during the rework process to be more challenging. Higher reflow temperatures of 'lead free' rework increases the pressure for properly shielding the neighboring components. These developments are causing BGA rework challenges. This summary will discuss the most challenging aspects of BGA rework and options for solutions.
Conclusions
The above discussion is a snapshot in time with respect to the top BGA rework challenges. These challenges, in no particular order, were that of: Excessive BGA warping due to thinning packages, shielding of neighboring devices in an era of increasing component density, underfilled BGA device removal and replacement, as well as the repair of solder mask. In addition to these current challenges others including reworking ever-finer devices pitches and integrating lower reflow temperature solders are rework trials that will be added to this list soon.
Initially Published in the SMTA Proceedings
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