Lead Free and Other Process Effects on Conductive Anodic FilamentationResistance of Glass Reinforced Epoxy Laminates

摘要

Conductive Anodic Filamentation is a subsurface failure mode for woven glass reinforced laminates (FR4) materials, where arncopper salt filament allows bridging between via walls or other copper conductors. In this study FR4 laminates, in the form ofrnhigh via density multi-layer test circuits, are exposed to different manufacturing conditions and assessed for resistance tornConductive Anodic Filamentation (CAF). CAF performance was assessed using high temperature and humidity conditions tornpromote failures, with a voltage applied across adjacent vias. By application of a range of voltages and via geometries arnperformance map for laminates can be obtained to compare materials for performance. The changes due to exposure ofrnlaminate to lead-free temperatures and other processing steps are then examined using the technique.