An inspection process based on scanned-beam X-ray laminography (SBXLAM) is proposed herein for quantitatively monitoring the quality of ball-grid-array (BGA) joints. The long-term reliability of the BGA joints depends on the component-assembly process producing joints with sufficient solder volume and proper alignment. Inspection algorithms were developed to measure the critical BGA-joint characteristics, including the alignment between the ball and the PCB pad, the solder thickness, and the average joint-diameter, and thus, determine whether the joints are defective. The performance of the inspection algorithms was evaluated by inspecting samples with defects that were independently verified.
No takes yet. Share an insight, caveat, or question.
Rooks et al. (1995) studied this question.
Synapse has enriched one closely related paper. Consider it for comparative context: