Applicability Evaluation of Nano-Al2O3 Modified Sn-Ag-Cu Solder in High-Density Electronic Packaging Subjected to Thermal Cycling

Abstract

Recently, 3D packaging has been regarded as an important technical means to continue Moore’s Law. However, excessive stacking will increase the longitudinal dimension, and one chip with high-density bondings packaging is still needed. Thus, it naturally places higher demand on thermal cycling reliability due to the decreased joint size to satisfy high-density packaging. In this work, the nano-Al2O3 (1 wt.%) modified Sn-1 wt.% Ag-0.5 wt.% Cu low-Ag solder was applied as a solder sample to evaluate the associated thermal cycling reliability. The investigated results revealed that the nano-Al2O3 modified solder did present enhanced thermal cycling reliability, as evidenced by the delayed microstructure coarsening and the inhibited atom inter-diffusion at interface caused by the adsorption of nano-Al2O3 on grain surfaces, and the resultant pinning effect. Worthy of note is that the potential of the newly developed nano-Al2O3 modified solder for high-density packaging applications (e.g., BGA, QFN, and CCGA) was evaluated based on the Finite Element Modeling.

Effect of Si3N4 nanowires doping on microstructure and properties of Sn58Bi solder for Cu bonding

“…On the other hand, electronic packaging must also possess characteristics such as higher signal transmission speeds and improved heat dissipation efficiency to meet the requirements of integrated circuits. However, the number of transistors in integrated circuit chips is approaching the limit, which also brings new challenges to electronic packaging technology (Wu et al , 2023). The application and development of novel types of packaging technology and materials inevitably require breaking through traditional limitations to achieve solder joints with higher strength (Hu et al , 2017).…”