To test for ball grid array (BGA) failure, you will need to use the dye and pry test method. This is a destructive test, but it is the most cost-effective way to examine the solder connections of the BGA and display cracks and leaks on the sealed parts.
What is the dye and pry test?
Dye and pry testing, also known as the dye penetrant test, is done to reveal discontinuities that may be hidden beneath surface mount technology (SMT) components.
How to test for BGA failure
- First you will need to remove the area of the board that contains the target component by using a diamond saw blade. Be careful to tamper vibrations and shear forces because they could put the integrity of the sample in jeopardy and create defects that weren’t there before.
- Following the above, you will need to immerse the sample into a red dye of low viscosity. This must be done inside a vacuum chamber so that the capillary action can pull the dye into each crevice. The pressure of the vacuum helps with this aspect.
- Once the dye immersion is complete, take your sample and bake it until dry in a moisture removal oven. The oven in your kitchen will not suffice.
- After baking, you will need to separate the component from the board with a puller assembly. Be careful when doing this to avoid breakage.
- The last step involves examining the component under a microscope to check for defects. If the dye does not penetrate and stain the component, then that signals that it is intact. However, if the dye does penetrate and stain the component, it will reveal any fractures on the solder joints.
Why do we use the dye and pry test?
Dye and pry testing provides a lower cost per joint and little sample preparation time. Furthermore, it allows you to look at all the solder connections at once and discover any anomalies. It’s important to keep in mind that the right equipment is necessary for the dye and pry testing process. Most people rely on professional testing companies and other electronics firms to provide the testing. If you try to test for BGA failures on your own, make sure you are using the right equipment and carefully handle the target component.
Please contact Circuits Central for more information about the dye and pry test process.