Uncovering the multi-stage evolution process and corrosion failure mechanism of typical electronic interconnections in condensation environments

This study investigates the failure dynamics and dendrite growth characteristics under simulated condensing conditions, employing real‑time current monitoring, localized pH testing, and comprehensive characterization. The results reveal that condensation‑induced electrochemical migration (ECM) is a continuously evolving dynamic failure process, which can be divided into five distinct stages. It initiates with the heterogeneous nucleation and growth of surface dew droplets, followed by droplet coalescence to form a continuous liquid film. This subsequently triggers pitting and dissolution of the tin‑based alloy anode, after which tin ions migrate toward the cathode and deposit continuously. Ultimately, dendrites bridge the electrodes, leading to short‑circuiting. The dendrites formed during migration consist of the β‑Sn single phase, and their morphological evolution is governed by the ion concentration gradient. Notably, silver and copper from the alloy do not migrate but remain as detached particles within the interdendritic gaps.