Anyone working with BGA solder joint reliability should be used to X-ray detection, made possible by Si-Li and Ge-Li as well as Cd-Te and Cd-Zn-Te. These materials sense the X-rays and convert them into an electrical signal. X-ray equipment is great for classifying voids in BGA solder joints, some thermal interfaces, power die attach, and an array of different solder-related applications.
We've seen a lot of these x-ray images, and they usually tell a good story. If you'd like to share your x-ray story, send it to firstname.lastname@example.org. Disclosable stories can be shared on the blog.