Ball Grid Arrays (BGAs)
During PCB assembly and manufacturing, Ball Grid Arrays (BGAs) may need to be re-balled, from time to time. Sometimes a BGA may get damaged or a cold solder or bridge is created, which require depopulating the BGA for BGA Rework. The EMS provider should have certain capabilities and experience to deal with this issue. Those capabilities involve printed circuit board materials, BGA placement systems, and specific BGA rework systems.
If a particular BGA-populated application requires considerable rework, it’s a good idea to select a high-temperature FR4 material like FR408 or FR406 due to their tolerance for high temperature re-flows. BGA assembly, BGA inspection, removing and populating systems play a major role in manufacturing. Of particular importance is BGA placement system with bottom heaters that provides uniform temperature across the entire PCB, on top PCB surface as well as on bottom PCB surface. Lastly, the OEM should expect the EMS provider to perform BGA rework on a standalone system for testing purposes, as well as installing BGAs as part of SMT applications.
BGAs can be damaged by excessive heat being applied as a result of using wrong thermal profile at the reflow ovens in the manufacturing stages. The key to install a clean BGA is to make sure that the PCB surface is flat and clean, using the right thermal profile and proper BGA placement system and verifying this placement by using a high powered X-ray machine.
To summarize, it is important to assure that pin-configurable BGAs should be partitioned properly using the correct ground and power pins outs. These BGAs should also be routed with utmost care to make sure that decoupling is properly implemented, and noise has been suppressed. At the manufacturing level, each BGA should be properly mounted with a precise vision placement system and then its connections verified by powerful X-ray equipment.
For further information on Ball Grid Arrays (BGAs) Assembly, BGA repair, and BGA rework, Contact us for free consultation and quote.
To learn more about BGAs, visit our Ball Grid Array (BGA), Underfill, BGA Escape Routing Tips, and Via in Pads and BGA pages.