Abstract
Conductive anodic filamentation is a subsurface failure mode in woven glass-reinforced laminate (FR4) materials, where a copper salt filament allows bridging between via walls and other copper conductors. In this study, FR4 laminates, in the form of high-via-density multilayer test circuits, are exposed to different manufacturing conditions and assessed for resistance to conductive anodic filamentation (CAF). CAF performance was assessed using high temperature and humidity conditions to promote failures, with a voltage applied across adjacent via. By the application of a range of voltages and via geometries, a performance map for laminates can be obtained to compare materials for performance. The changes due to exposure of laminate to tin–lead and lead-free temperatures are then examined using the technique.
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Acknowledgments
The work was part of a project in the Materials Processing Metrology Programme of the UK Department of Trade and Industry. NPL gratefully acknowledges the work of the industrial partners: Alcatel Submarine Networks, TRW Automotive Group, Graphic Plc, Prestwick Circuits, Invotec, Isola and Polyclad.
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© 2011 Springer-Verlag London Limited
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Zou, C., Brewin, A., Hunt, C. (2011). Lead-Free and Other Process Effects on Conductive Anodic Filamentation Resistance of Glass-Reinforced Epoxy Laminates. In: Grossmann, G., Zardini, C. (eds) The ELFNET Book on Failure Mechanisms, Testing Methods, and Quality Issues of Lead-Free Solder Interconnects. Springer, London. https://doi.org/10.1007/978-0-85729-236-0_11
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DOI: https://doi.org/10.1007/978-0-85729-236-0_11
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