Inspection Leakage
Statistical measurements quantify the percentage of minute fractures in a substrate or component that bypass quality control filters and reach the customer. A high micro-cracking defect escape rate indicates that the detection system is insensitive to the specific size or orientation of these flaws. These defects often reside inside buried vias or along the interface of the resin and glass fibers.
Automated optical inspection frequently misses such internal anomalies.
Detection Failure
Hardware limitations in scanning resolution or lighting angles prevent the identification of tight cracks. If the micro-cracking defect escape rate rises, the probability of field failures increases as these cracks expand during operation. Latent defects are particularly dangerous because they pass initial electrical continuity tests.
Environmental stress screening may catch some failures, but it cannot find every weakened site. High-volume production lines must balance throughput with the sensitivity of the inspection algorithms. Process engineers monitor this rate to determine when to calibrate cameras or update x-ray parameters.
Quality Cost
Warranty claims and brand damage outweigh the expense of better screening. Calculating the micro-cracking defect escape rate requires comparing internal yield data against downstream failure reports. Rigorous sampling plans provide the necessary data.
Effective filters reduce the risk to zero.
