Final Steps of BGA Repair: A Comprehensive Guide – Part II

May 08,2017

BGA rework is a very critical process, and it requires a high level of expertise in handling the equipment with precision. In the last post, we covered a few steps of the BGA rework process. In this post, we will move forward with the final steps of this process.

Repairing BGA Assembly

Here are the final steps that complete the process of BGA repairing:

• Step 6 – Placing BGA Solder Spheres: A special machine or custom tooling is used to place solder spheres on the ball grid assembly. Make sure that you use good quality solder spheres of high tolerances for a better application.

• Step 7 – Reflow: In this step, the equipment is dismantled, and faulty circuit board is removed. The removed boards are placed in an oven for preheating. Once this is done, the non-functioning components are heated to melt the solder. The boards are cooled, which is followed by deciding on the thermal profile and reassembly. By this process, a bad connection can be repaired without the need of removing or replacing the components.

• Step 8 – BGA Reball Inspection Process: As the name of the step implies, inspection of the reballed BGA is performed in this step. It is checked for bridge spheres, and co-planarity. If the BGA has any bridge spheres, then the step 7 above is repeated.

• Step 9 – Cleaning Reballed BGA: This is the cleaning stage, where the reballed BGA is treated with water and isopropyl alcohol to enhance its appearance, and make it look new. You may also use acetone for the cleaning purpose. If the BGA is heavily soiled, then you can use ultrasonic cleaners to clean it.

• Step 10 – BGA Reball Inspection Process: The reballed BGA is inspected again for any minor faults. This step is repeated after cleaning stage, so that it gives a clearer view of the assembly, and makes it easier to spot faults.

• Step 11 – Baking Reballed BGA Again: This is the last step in the rework process. In this step, the reballed BGA is baked again at 125° C. This ensures that the assembly is dry and ready to bear the reflow temperatures during the PCB manufacturing process.

With this, it completes the process of BGA rework. If you follow all the steps covered in this post and the previous one, you will be able to do a better BGA repair. You may also opt getting the assembly repaired from an expert like Creative Hi-Tech. The company is known for providing PCB design and assembly. They are experts in BGA assembly manufacturing, as well as rework.