Interdiffusion between Cu and Sn-rich solder: dominant diffusion species

Author

Kim, Si-Jung ; Bae, Kyoo-Sik

Author_Institution

Dept. of Electron. Mater. Eng., Suwon Univ., South Korea

fYear

2000

fDate

2000

Firstpage

81

Lastpage

85

Abstract

Extensive microstructural and kinetic studies on the formation and growth of the intermetallics of Sn-rich solder/Cu couples have been reported. However, experimental data on the dominant diffusing species are limited and in conflict. The dominant diffusing species for the soldering and aging of Sn-3.5Ag alloy/Cu couples were investigated by using an unsoldered or Cr-evaporated surface as a reference line. After soldering, the Sn-rich alloy on top of the scallop-shaped Cu₆Sn₅ intermetallic compound was observed below the original Cu surface. Sn was also observed to diffuse to Cu during the aging process. Therefore, Sn was suggested to be the dominant diffusing species for both soldering and aging

Keywords

ageing; assembling; chemical interdiffusion; copper; interface structure; packaging; silver alloys; soldering; tin alloys; Cr-evaporated surface reference line; Cu; Cu surface; Cu₆Sn₅; Sn diffusion; Sn dominant diffusing species; Sn-Ag alloy/Cu couples; Sn-rich alloy; Sn-rich solder; Sn-rich solder/Cu couples; SnAg-Cu; aging; aging process; dominant diffusing species; dominant diffusion species; interdiffusion; intermetallic formation; intermetallic growth; kinetic study; microstructural study; scallop-shaped Cu₆Sn₅ intermetallic compound; soldering; unsoldered surface reference line; Aging; Copper alloys; Electronics packaging; Intermetallic; Kinetic theory; Lead; Soldering; Substrates; Temperature; Tin;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronics Packaging Technology Conference, 2000. (EPTC 2000). Proceedings of 3rd

Print_ISBN

0-7803-6644-1

Type

conf

DOI

10.1109/EPTC.2000.906353

Filename

906353