The process of BGA rework on a motherboard involves several complex steps that must be strictly followed to ensure successful rework. Let’s delve into the specific methodological steps for BGA rework on motherboards, as detailed by Silman Tech, a manufacturer of BGA rework stations.
- Soldering Method for Motherboard BGA Pins: Considering the dense arrangement of pins on the motherboard’s BGA, they typically cannot be directly routed from the top layer. Instead, they need to be routed through vias to the bottom layer, avoiding the outermost pins.
- Configuration of Solder Paste during BGA Rework: Apply solder paste onto the top-layer pads and vias leading to the pads, followed by applying it to the bottom-layer pads leading to the vias. The solder paste must be clean, and the cleaning solution used for the board must also be clean.
- Ensuring Proper Alignment of BGA Chip Pins for Successful Soldering: Align the pins of the chip BGA on the motherboard. This step is challenging, but rough alignment is usually sufficient. Ensure that the pins do not touch adjacent pad vias.
- Setting the Melting Point of Solder Paste for Motherboard BGA Rework: Use a hot air gun to heat the pads leading to the vias on the bottom layer. Avoid using a nozzle attachment on the hot air gun to prevent uneven heating. Directly using a wide nozzle should provide uniform heating, as the surface area of BGA chip packages is not large. Heat the pins on the BGA chip until they melt, typically for about 10 seconds, until the solder paste fumes dissipate.
- Cleaning the BGA: After completing the above steps, clean off the black residue from the solder paste using clean washing solution. With this step, the basic process of BGA rework soldering on the motherboard is completed.
If you lack experience or require high precision due to large batch sizes, it’s recommended to invest in a professional BGA rework station. Using such equipment significantly improves the speed and efficiency of the rework process, leading to a higher success rate. After training and guidance from Silman Tech, for instance, the success rate of BGA rework using their equipment typically exceeds 99%. If you don’t have a BGA rework station yet, consider exploring Silman Tech’s offerings, which feature automatic BGA chip rework with exceptionally high success rates, chosen by many globally renowned companies.