UNDERSTANDING PCB DESIGN VARIABLES that Contribute to Warpage during Module-Carrier Attachment

摘要

Phase 1. The evaluation determined incoming PCB coplanar-ity had an impact on yields of the assembly of the module to the carrier. Panels sorted into group A demonstrated a lower ppm defect level than those in the B and C groups. The ppm defect levels rose significantly in Group B and nearly doubled in Group C. Group A had a lower average coplanarity than those in Groups B and C. Despite the sorting at the panel level, Group A still had individual modules with high-copla-narity values but at a lower percentage than the other groups.