Effect of Cu6Sn5/Ag3Sn Nanoparticles Addition on Properties of SAC305 Microstructure and Reliability of Solder

In this study synthesized Ag 3 Sn and Cu 6 Sn 5 Nanoparticles (NPs) via the redox method, then incorporated them into Sn‐3.0Ag‐0.5Cu (SAC305) solder to produce SAC305‐0.15Ag 3 Sn‐xCu 6 Sn 5 ( x = 0 wt%, 0.05 wt%, 0.1 wt%, 0.15 wt%, and 0.2 wt%). The effects of thermal properties, wettability, microstructure, Vickers hardness, tensile strength, and joint reliability were systematically explored. Results showed adding dual NPs increased the melting point, inhibited excessive intermetallic compound (IMC) growth, and refined the microstructure. SAC305‐0.15Ag 3 Sn‐0.15Cu 6 Sn 5 had a spreading area of 88.5565 mm 2 , 8.50% higher than SAC305‐0.15Ag 3 Sn. Mechanical property analysis revealed that the solder alloy containing dual NPs exhibited higher Vickers hardness and tensile strength in the solder joints, with maximum values of 12.02 HV and 56.68 MPa, respectively. Aging tests revealed they inhibited interfacial IMC layer growth, with the minimum growth coefficient at 0.0180.