The Mechanical Properties and Elastic Anisotropy of η′-Cu6Sn5 and Cu3Sn Intermetallic Compounds

Abstract

Full intermetallic compound (IMC) solder joints present fascinating advantages in high-temperature applications. In this study, the mechanical properties and elastic anisotropy of η’-Cu6Sn5 and Cu3Sn intermetallic compounds were investigated using first-principles calculations. The values of single-crystal elastic constants, the elastic (E), shear (G), and bulk (B) moduli, and Poisson’s ratio (ν) were identified. In addition, the two values of G/B and ν indicated that the two IMCs were ductile materials. The elastic anisotropy of η’-Cu6Sn5 was found to be higher than Cu3Sn by calculating the universal anisotropic index. Furthermore, an interesting discovery was that the above two types of monocrystalline IMC exhibited mechanical anisotropic behavior. Specifically, the anisotropic degree of E and B complied with the following relationship: η’-Cu6Sn5 > Cu3Sn; however, the relationship was Cu3Sn > η’-Cu6Sn5 for the G. It is noted that the anisotropic degree of E and G was similar for the two IMCs. In addition, the anisotropy of the B was higher than the G and E, respectively, for η’-Cu6Sn5; however, in the case of Cu3Sn, the anisotropic degree of B, G, and E was similar.

Effects of Cu/SnAgCu Powder Fraction and Sintering Time on Microstructure and Mechanical Properties of Transient Liquid Phase Sintered Joints

“…As shown in Figure 11, the ratio of the Cu 6 Sn 5 IMC decreased during the reliability tests due to the transformation to the Cu 3 Sn IMC. It has been reported that the mechanical strength of the Cu 3 Sn IMC is typically higher than that of its Cu 6 Sn 5 counterpart [42,58,59]. Thus, a larger ratio of the Cu 3 Sn IMC could be attributed to the higher shear strength of the sintered joints.…”

“…Such characteristics are beneficial for electronic packaging technology, suppressing the risk of thermal damage to sensitive electronic devices. During Cu-Sn sinter bonding, Cu 6 Sn 5 and Cu 3 Sn IMCs commonly form in the sintered joints [42][43][44]. Such a process leads to the complete formation of a liquid phase of the low-meltingtemperature metal and IMC transformation.…”

Effect of Different Concentrations of Co Doping on the Properties of η′‐Cu6Sn5 and Ni3Sn4: First‐Principles Study

“…It is defined as the Taylor expansion of the system's total energy with respect to the small strain in the volume of the original lattice unit. [27,28] Since both Ni 3 Sn 4 and η 0 -Cu 6 Sn 5 are monoclinic structures, their stability conditions were determined using the following equations [29] C 11 > 0,…”

“…It is defined as the Taylor expansion of the system's total energy with respect to the small strain in the volume of the original lattice unit. [ 27,28 ] Since both Ni 3 Sn 4 and η′‐Cu 6 Sn 5 are monoclinic structures, their stability conditions were determined using the following equations [ 29 ] …”

Crystal structure informed mesoscale deformation model for HCP Cu6Sn5 intermetallic compound

“…In this study, η-Cu 6 Sn 5 is considered as the material for computational analysis. The currently widespread applications such as high-powered electronic equipment and third generation semiconducctor power devices have high service temperature ( T > 523.15 K) requirements [7], and this makes the study of η-Cu 6 Sn 5 phase more relevant.…”