CCA-SAFE: A Model-Assisted NDE Tool for Failure Analysis of Gold Contaminated Solder Joints

Gold contamination in Circuit Card Assembly (CCA) solder joints leads to brittle intermetallic compounds (IMCs), which is one of the major factors in solder joint failure. The conventional rule of thumb considers 3 wt% of gold (Au) as a safety threshold, which is not always reliable due to varieties of package platforms, solder types, reflux settings, operational and environmental conditions, etc. Accurate assessment of solder reliability requires physical understanding of solder behavior under realistic loads and boundary conditions. In this Phase I project, Intelligent Automation, Inc. proposes to develop a modeling and Nondestructive Testing (NDT) combined framework for Au content detection and solder failure likelihood prediction. In the proposed framework, NDT data of Au distribution will be imported into a multi-scale model integrating Finite Element Analysis (FEA) and Peridynamics (PD) for crack initiation and growth analysis. An efficient stochastic algorithm will be utilized to interrogate the numerical model in the random space, generating probabilistic failure prediction toward the target sample and operation condition. Feasibility of the proposed method will be evaluated on representative solder joint specimens with different levels of gold contents. Approved for Public Release 16-MDA-8620 (1 April 16)