Silver Sintering and Soldering: Bonding Process and Comparison

  • S. ChenEmail author
  • H. Zhang


Silver sintering materials are one of the promising candidates for die attach to survive harsh operation conditions (≥200 °C) in applications such as hybrid/electric vehicles, high-speed train, aircraft/aviation, and deep well oil/gas extraction. This chapter focuses on elucidation of the joint formation processes of silver sintering and solder, as well as their comparison. The driving force of silver sintering is particle surface energy reduction. It occurs through solid-state atomic transportation such as various diffusions and viscous flow processes. Non-stoichiometric interdiffusion layer is generated through mutual atomic diffusion between silver and joining surface metallization. In contrast, solder joint is formed through metallurgical interaction between molten solder and joining surfaces followed by solder solidification, where stoichiometric intermetallic is normally observed at interfaces. Therefore, silver sintering joint may possess porosity, which greatly reduces its bulk mechanical properties such as elastic modulus, yield strength, strength to failure, ultimate tensile strength, and Poisson’s ratio, as well as its thermal and electrical conductivities.


Silver (Ag) sintering paste Pressure Pressureless Die attach Porosity Void High temperature Surface finish Power electronics Solder 


Acknowledgment and Note

We gratefully thank Dr. Ning-Cheng Lee for his continuous support during the writing of this chapter. Dr. Hongwen Zhang focused on Sect. 2; Dr. Sihai Chen was in charge of Sects. 1, 3, 4, 5, and 6.


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Authors and Affiliations

  1. 1.Indium CorporationClintonUSA

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