Root Cause Failure Analysis of Dendrite Shorting: A Comparison of Analytical Techniques
Author: Terry Munson Company: Foresite Inc. Date Published: 9/28/2014
Abstract: This paper will explore the investigative techniques used to determine the root cause of a circuit failure on the surface of a conformal coated assembly. Shorting (electrochemical migration / dendrite) occurred on top of an SMT pad location causing a hard short. Typical failure analysis tools (e.g. SEM/EDS, FTIR and ion chromatography) were used to determine the conditions and process steps that caused the failures. The results from each testing technique will be addressed and the case study will show the root cause conditions that are associated with particular processing steps.
electrochemical migration, dendrite short, SEM/EDS, FTIR, IC analysis, C3 extraction