ETECH inside faq

What do I need to provide to do 5DX inspection?

You must have a CAD file, a BOM and a build classification. Gerber files and assembly drawings my be required. A complete rundown of requirements can be found here.

Can you assemble from trays, or do you require tape-and-reel?
We will complete assembly from either.

What is involved in BGA reballing?
  1. Bake PCB – BGAs must be free of moisture prior to removing them from a PCB. The chip can be dried by baking the entire PCB per JEDEC standards (usually 125°C for 24 hours, but each board must be evaluated first). This removes moisture from the chip and PCB and eliminates the risk of “popcorning” the internal die of the BGA. If baking is not performed the component may be damaged. If damage does occur, the BGA cannot be repaired. Popcorning is often not visible to the naked eye and may only become apparent once the chip is placed back in service. eTech has the capacity to bake PCBs up to 33”x26”. We have multiple ovens and can accommodate a large quantity of PCBs and BGAs at one time.
  2. Remove BGA – The BGA removal process is performed using custom thermal profiles for each PCB and BGA location. Our operators are trained to spot potential problems during the BGA removal process.
  3. Bake BGA – BGAs must be dry before reballing can be attempted. BGAs do not need to be re-baked if they have not been subjected to atmospheric moisture after being removed from the PCB. BGAs that have been exposed to moisture in excess of the manufacturers’ moisture rating are baked 24 hours at 125°C. eTech’s philosophy is, “If in doubt, bake, because there is no such thing as too dry”.
  4. Site Dress BGA – eTech dresses BGA’s by hand under a microscope, removing the existing solder and cleaning the surface. Great care is taken to restore the component to its original condition, if possible.
  5. BGA Inspection – eTech carefully inspects each BGA under a microscope.
  6. Paste High Temperature BGA – Pasting is generally only required on high-temp BGAs to create a fillet around the spheres that do not reach reflow temperature during the BGA reballing process.
  7. Place BGA Solder Spheres – eTech designs and manufactures custom tooling for the application of solder spheres on BGAs. This gives eTech the flexibility to accommodate customer BGA reballing requirements including fine pitch (down to .4mm) and mixedpitched arrays, and to provide quick-turn reballing of small quantities as well as quantities of greater than 10,000 pieces. We use top quality, high tolerance solder spheres in our BGA reballing process. We stock both standard and metric sizes of lead and lead-free solder spheres. We keep more than 5 million spheres in stock to meet our customer’s BGA reballing needs.
  8. Reflow BGA – A thermal profile is developed and the BGA is heated to complete the process. Reballing temperatures are generally cooler than PCB assembly temperatures, as both sides of the component are exposed.
  9. BGA Reball Inspection Process – each reballed BGA is inspected after reflow to ensure adequate reflow, co-planarity, bridged spheres, etc.
  10. Clean/Wash Reballed BGA – isopropyl alcohol and water are used to hand wash the reballed BGA.
  11. BGA Reball Inspection Process – each reballed BGA is inspected again to check for cleanliness and any defects that might have been missed.
  12. Bake Reballed BGA – Depending on the process and chemistry used, reballed BGA’s are re-baked at 125°C to ensure that the BGA’s are dry and ready to encounter reflow temperatures during manufacturing.
  13. Mark or Dot BGA – eTech’s standard practice when reballing BGAs is to mark each chip, usually with a red dot on the top side of the BGA in the pin one corner. We can vary the color of the dot or use custom marking on request.
  14. Pack / Seal / Certificate of Compliance – Reballed BGAs are vacuum-packed and sealed in moisture-proof, antistatic bags. Moisture indicator strips and desiccant are included. We include a certificate of compliance for each job.

Do you have to bake my BGAs? How long will that take?

We recommend baking BGAs to meet with Joint Industry Standard Baking and Moisture Specifications J-STD-033B.

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PDFs of:
5DX requirements
quote requirements