SMT Reflow Temperature Profiling and Defect Analysis for Lead Free Assemblies
Optimized lead-free reflow profiling requires thermal deltas under eight degrees, controlled time above liquidus, and precise paste transfer efficiency.
3d X-Ray Laminography
Tomographic Reconstruction
Radiographic inspection techniques using planar motion provide high resolution imaging of specific horizontal depths within a solid assembly. This 3d x-ray laminography isolates a single plane of interest by moving the source and detector in synchronous patterns. Results show a sharp focus at the fulcrum height while features above and below that level appear blurred.
Layer Isolation
Vertical reconstruction relies on capturing multiple angular projections to resolve overlapping features in complex board designs. Because 3d x-ray laminography focuses on a specific slice, it allows inspectors to examine double sided surface mount assemblies without interference from the opposite side. Individual solder joints appear as distinct images.
Automated algorithms then compare these slices against design data to detect voids or shorts.
Defect Resolution
Specific defect identification occurs when the software processes these isolated layers to find structural anomalies that would escape detection in a single plane of focus. Unlike traditional x-ray, 3d x-ray laminography provides the depth information needed to verify heel fillets on leadless components. The system identifies insufficient wetting or head in pillow defects that would remain hidden in a standard top down view.
Mechanical precision of the motion system determines the accuracy of the final image. Precision matters.