Shear performance of microscale ball grid array structure Cu(Ni)/Sn–3.0Ag–0.5Cu/Cu(Ni) solder joints at low temperatures. (March 2022)

• Record Type: Journal Article
• Authors: Li, Wangyun; Gui, Jun; Qin, Hongbo; Yang, Daoguo
• Is Part Of: Materials today communications. Volume 30(2022)
• Publication Date: 2022-03
• Subjects: Solder joint -- Low temperatures -- Shear strength -- Fracture mechanism; Materials science -- Periodicals; 620.11
• DOI: 10.1016/j.mtcomm.2022.103149
• Languages: English
• ISSNs: 2352-4928

Abstract

Abstract: In this study, the shear performance of microscale ball grid array structure Cu/Sn–3.0Ag–0.5Cu (SAC305)/Cu, Cu/SAC305/Ni, Ni/SAC305/Cu, and Ni/SAC305/Ni solder joints was investigated at decreasing temperatures (25 °C, 0 °C, −25 °C, −50 °C, −75 °C, −100 °C, and −125 °C). The results showed that the shear performance of the solder joints was considerably influenced by both the temperature and substrate materials. The shear strength of the Cu/SAC305/Cu solder joint monotonically increased with decreasing temperature, whereas the shear strength first increased and then decreased for the other solder joints. The fracture positions of all solder joints shifted from the solder matrix to the interface between the solder matrix and intermetallic compound layer when the temperature decreased, and the fracture mechanism changed from ductile to brittle with a ductile-to-brittle transition temperature of approximately −75 °C. Moreover, the interfacial fracture of the Cu/SAC305/Ni and Ni/SAC305/Cu solder joints was prone to occur at the Ni substrate side. Graphical Abstract: ga1 Highlights: DBTT of the solder joints is independent of the substrate metallization, which is about −75 °C. Shear strength increases monotonically in the Cu/SAC305/Cu solder joint as temperature decreases. Shear strength increases above the DBTT and then decreases below the DBTT in the solder joints with Ni substrate. The brittle interfacial fracture prefers to occur at the Ni substrate side interface.