High Resolution Automatic X-Ray Inspection for Continuous Monitoring of Advanced Package Assembly

Abstract

At the same time that IC packaging interconnect is being driven towards higher density and more solder connections, the market's tolerance for defective materials is rapidly disappearing. Existing techniques for inspecting solder joints inside of packages such as cross sectioning and conventional high-resolution X-ray are time consuming and impractical for 100% monitoring and process feedback. A novel X-ray system architecture combined with advanced machine learning algorithms enables high speed automated inspection of complex IC package structures. Just as Automated Optical Inspection (AOI) has been widely deployed for visible structures and Automated X-ray Inspection (AXI) for Ball Grid Array solder joints, High Resolution Automated X-ray inspection (HR-AXI) brings inline inspection to fine pitch flip chip solder joint assembly processes. HR-AXI delivers orders of magnitude higher inspection speeds with greater sensitivity than conventional point projection X-ray systems. Device damage is reduced as a result of shorter exposure times and an optimized system configuration. Using single top down images, advanced machine learning algorithms rapidly find defects such as non-wets, voids, and bridges.