Sintered silver (Ag) bonding is a promising technology in power electronics packaging due to its excellent thermal and electrical conductivity. However, mechanical reliability under thermal and mechanical stress remains a significant concern. This study investigates the impact of incorporating micron-sized copper (Cu) particles into nanosilver paste on the mechanical and thermal properties of sintered Ag films. In-situ SEM (scanning electron microscopy) tensile testing was performed on microscale Cu-included sintered Ag films to assess their fracture behavior and mechanical response, the Cu-containing samples exhibited a more brittle fracture mode. Notably, these samples showed improved stiffness at elevated temperatures, indicating greater mechanical stability in harsh environments. Thermal shock testing (TST) further demonstrated enhanced bonding reliability in the Cu-included films, with increased resistance to degradation under cyclic thermal loading. The combined mechanical and thermal results suggest that the addition of Cu particles significantly improves the durability and robustness of sintered Ag joints. These findings support the potential use of Cu-included sintered Ag films as a more reliable die-attach material for silicon carbide (SiC) power modules, offering improved performance under high-temperature and high-stress operating conditions.
Chantawong et al. (Wed,) studied this question.