The increasing complexity of electronic components imposes limits on two-dimensional radioscopy, such as in double-sided board assemblies where individual elements overlap. That is where 3D technologies such as computed tomography (CT) or computed laminography (CL) come in.

Cracks in bonding wires can reliably get detected using computed tomography; however, it is not non-destructive because CT can only get applied with small samples. Therefore, the area to be inspected must get cut out of the board. When it comes to evaluating individual, overlapping layers, computed laminography is the technology that provides definite results. That is particularly important for detecting HoP defects in BGAs, problems in inner layers, trace interruptions, and, of course, surface soldering, which must get checked for voids to ensure the functionality of the component.

A void analysis is necessary at BGA, LGA, IGBT, BTC, QFN, and LED. Especially for BGA, computer laminography offers the possibility to measure voids separately at the top and bottom of the interfaces, where they are particularly critical. Voiding at the interfaces has a direct influence on e.g. the thermal stability of the entire BGA. By dividing the virtual 3D volume into individual cross-sections, the voiding at the interfaces can precisely get evaluated.

With additional possibilities to integrate laminography sequences into inspection programs and the new VoidInspect software for automatic evaluation of voids, users benefit from high-quality images at increased inspection speed. Laminography 3D volumes can even be created with very few projections to achieve high-quality void analyses.




Speaker: Peter Koch, Yxlon International

Dipl.-Ing. Peter Koch studied materials science at the FAU Erlangen-Nuremberg. He has been working in electronics for over 20 years, including 17 years in X-ray inspection focusing on DR, CL, and CT. As a product manager and specialist for failure analysis in electronics, he supports further developments of features and workflows.