基于片上嵌入式温度传感器在高电流密度下微凸点电迁移诱导退化的表征

This study investigates electromigration-induced degradation in micro bumps through an integrated experimental and computational approach. Platinum thin-film temperature sensors were embedded within flip-chip specimens to enable real-time thermal monitoring. Internal package temperatures were measured using these sensors, with validation via infrared thermography, to quantitatively characterize Joule heating effects under high-current-density conditions. Cross-sectional SEM analysis of specimens subjected to accelerated current stressing revealed that electromigration drives two concurrent failure mechanisms in electro-thermal coupling environments: (1) void nucleation-propagating along IMC/solder boundaries, and (2) necking caused by accelerated solder consumption. A multi-physics modeling framework combining unified creep plasticity (UCP) constitutive laws with the J-integral fracture mechanics method was developed to simulate shear deformation evolution in micro bumps containing electromigration-induced voids. Computational results demonstrated that void propagation disrupts hydrostatic stress uniformity, inducing localized stress concentrations near solder-depleted regions. Crucially, solder consumption-induced voids exhibited higher stress intensification compared to IMC-interface voids, establishing a direct correlation between void topology and mechanical reliability degradation.