The anti-electrochemical migration mechanism of Ag-based transient liquid-phase electrically conductive adhesive: Experimental and phase-field study

Abstract

Silver (Ag)-based electrically conductive adhesives (ECAs) are extensively utilized in electronic packaging applications owing to their exceptional mechanical and electrical properties. Enhancing the anti-electrochemical migration (ECM) properties of Ag-ECA is crucial for enhancing its electrical reliability and broadening its applicability. In this study, a novel transient liquid-phase electrically conductive adhesive (TLP-ECA) was developed by incorporating low melting point alloy (LMPA) particles into Ag-ECA, and its anti-ECM characteristics were assessed through water droplet test. Additionally, the investigation employed experimental analysis, phase-field simulations, and first-principles calculations to elucidate the extrinsic and intrinsic mechanisms responsible for enhancing the anti-ECM performance of TLP-ECA. The findings demonstrated that the addition of LMPA particles significantly enhanced the anti-ECM performance of TLP-ECA, evident in the 5.5-fold increase in short-circuit time compared to Ag-ECA. Notably, the enhanced anti-ECM characteristics in TLP-ECA were primarily attributed to the formation of an anodic surface oxide layer, referred to as the extrinsic mechanism, coupled with the existence of intermetallic compounds, denoted as the intrinsic mechanism. The comprehensive exploration of the anti-ECM enhancement mechanism of TLP-ECA through a synergy of experimental and computational methodologies offers valuable theoretical and practical insights for selecting electronic packaging materials with superior anti-ECM characteristics.