Microstructure, mechanical, and thermal properties of the Sn-1Ag-0.5Cu solder alloy bearing Fe for electronics applications

Microstructure, mechanical, and thermal properties of the Sn-1Ag-0.5Cu solder alloy bearing Fe for electronics applications: Author(s): Shnawah, D.A.-A. , Said, S.B.M. , Sabri, M.F.M. , Badruddin, I.A. , Che, F.X.
Publication year: 2012
Journal / Book title: Materials Science and Engineering A

This work investigates the effect of Fe addition on the microstructural, mechanical, and thermal properties of the Sn–1Ag–0.5Cu (SAC105) solder alloy. The addition of Fe leads to the formation of large circular FeSn2 intermetallic compound (IMC) particles, which produce a weak interface with the β-Sn matrix. The addition of Fe also leads to the inclusion of Fe in the Ag3Sn and Cu6Sn5 IMC particles. Moreover, Fe-bearing solders have been shown to form large primary β-Sn grains. The weak interface between the large FeSn2 IMC particles and the β-Sn matrix together with the presence of the large primary β-Sn grains results in a significant reduction on the elastic modulus and yield strength of the Fe-bearing solders. Moreover, the improved plasticity of the large primary β-Sn grains causes the Fe-bearing solders to exhibit large total elongation. The addition of Fe also significantly reduces the effect of aging. After aging at 100 °C and 180 °C, it has been observed that the Fe-bearing solders significantly suppress the coarsening of the Ag3Sn IMC particles; consequently, they exhibit stable mechanical properties. This effect can be attributed to the inclusion of Fe in the Ag3Sn IMC particles. In addition, fracture surface analysis indicates that the addition of Fe to the SAC105 solder alloy does not affect the mode of fracture, and all tested solders exhibited large ductile-dimples on the fracture surface. Moreover, the addition of Fe did not produce any significant effect on the melting behavior. As a result, the use conditions of the Fe-bearing solders are consistent with the conditions for conventional Sn–Ag–Cu solder alloys.



Materials Science and Engineering: A

Volume 551, 15 August 2012, Pages 160–168
Cover image
Microstructure, mechanical, and thermal properties of the Sn–1Ag–0.5Cu solder alloy bearing Fe for electronics applications

    Dhafer Abdul-Ameer Shnawaha, Corresponding author contact information, E-mail the corresponding author,
    Suhana Binti Mohd Saidb,
    Mohd Faizul Mohd Sabria,
    Irfan Anjum Badruddina,
    Fa Xing Chec

    a Department of Mechanical Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia
    b Department of Electrical Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia
    c Institute of Microelectronics, A*STAR (Agency for Science, Technology and Research), 11 Science Park Road, Singapore Science Park II, Singapore 117685, Singapore

Co addition to SAC - Malaysia

Factiva: "Effects of Co nanoparticle additions to Sn-3.8Ag-0.7Cu on the structure of solder/copper interface have been studied after reflow and high temperature aging (150 degrees C, up to 1008 h),' investigators in Kuala Lumpur, Malaysia report.

'the Co nanoparticles substantially suppress the growth of Cu3Sn but enhance Cu6Sn5 growth. Cobalt nanoparticles reduce interdiffusion coefficient in Cu3Sn,' wrote A.S.M.A. Haseeb and colleagues.

The researchers concluded: 'It is suggested that the Co nanoparticles undergo surface dissolution during reflow and exert their influence, at least partially, through alloying effect.'

Haseeb and colleagues published their study in Intermetallics (Effects of Co nanoparticle addition to Sn-3.8Ag-0.7Cu solder on interfacial structure after reflow and ageing. Intermetallics, 2011;19(5):707-712).

For additional information, contact A.S.M.A. Haseeb, University of Malaya, Dept. of Mech Engineering, Kuala Lumpur 50603, MALAYSIA."