Meaning
Non-destructive testing method that uses electromagnetic radiation to image the internal structure of an electronic assembly or component. X-ray inspection allows quality control technicians to evaluate hidden solder joints, internal voiding, and wire bond alignment without physically damaging the device. This technique is critical for inspecting complex packages like ball grid arrays where the solder joints are obscured from view.
Process Validation
Verification of solder quality is achieved by analyzing the density and shape of the solder connections on the circuit board. Automated x-ray inspection systems use computerized algorithms to detect bridges, shorts, and solder voids in real time on the assembly line. This rapid check allows operators to adjust the solder paste printing and reflow parameters before high volumes of boards are processed.
Component Verification
Counterfeit detection programs utilize radiography to compare the internal die size and lead frame geometry of a received batch against a known genuine reference. Discrepancies in the internal structure under x-ray inspection indicate that the components may be from a different production run or re-packaged. This step is a standard part of the incoming inspection protocol for high-reliability applications.
Technicians check the consistency of internal bond wire connections across all sampled units to ensure batch homogeneity.
Safety Limit
Exposure times and radiation levels must be carefully managed to prevent damage to sensitive semiconductor structures like flash memory cells. While x-ray inspection is generally considered non-destructive, excessive radiation doses can cause charge trapping and lead to premature failure of the device.
