Vol.30 No.4

Editorial Office


  • Journal of the Microelectronics and Packaging Society
  • Volume 30(4); 2023
  • Article


Journal of the Microelectronics and Packaging Society 2023;30(4):61-68. Published online: Feb, 20, 2024

Study on Sn-Ag-Fe Transient Liquid Phase Bonding for Application to Electric Vehicles Power Modules

  • Byungwoo Kim1 , Hyeri Go1 , Gyeongyeong Cheon2 , Yong-Ho Ko2 , and Yoonchul Sohn1†
    1Dept. of Welding & Joining Science Engineering, Chosun University 309 Pilmoon-daero, Dong-gu, Gwangju 61452, Korea, 2Advanced Joining & Additive Manufacturing R&D Department, Korea Institute of Industrial Technology, 156 Gaetbeol-ro, Yeonsu-gu, Incheon 21999, Korea
Corresponding author E-mail: yoonchul.son@chosun.ac.kr

In this study, Sn-3.5Ag-15.0Fe composite solder was manufactured and applied to TLP bonding to change the entire joint into a Sn-Fe IMC(intermetallic compound), thereby applying it as a high-temperature solder. The FeSn2 IMC formed during the bonding process has a high melting point of 513℃, so it can be stably applied to power modules for power semiconductors where the temperature rises up to 280℃ during use. As a result of applying ENIG surface treatment to both the chip and substrate, a multi-layer IMC structure of Ni3Sn4/FeSn2/Ni3Sn4 was formed at the joint. During the shear test, the fracture path showed that cracks developed at the Ni3Sn4/FeSn2 interface and then propagated into FeSn2. After 2hours of the TLP joining process, a shear strength of over 30 MPa was obtained, and in particular, there was no decrease in strength at all even in a shear test at 200°C. The results of this study can be expected to lead to materials and processes that can be applied to power modules for electric vehicles, which are being actively researched recently.

Keywords Sn-Ag-Fe, composite solder, TLP bonding, power module

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