Abnormal grain growth in Cu6Sn5 Grains formed at SN-based solder/Cu interfaces

Author

Ming Yang ; Mingyu Li ; Jianxin Wu ; Jinhua Xu

Author_Institution

Shenzhen Grad. Sch., Harbin Inst. of Technol., Shenzhen, China

fYear

2014

fDate

12-15 Aug. 2014

Firstpage

1181

Lastpage

1185

Abstract

Intermetallic compounds (IMCs) that form at eutectic Sn3.5Ag/Cu and pure Sn/Cu interfaces during solid-state aging are comparatively studied in terms of their respective morphological formations. During solid-state aging, all the interfacial Cu₆Sn₅ grains evolve into a layer-type morphology, except for select grains that experience abnormal growth. This abnormal growth is caused by the preferential growth of the Cu₆Sn₅ at the grain boundary in solder matrix. Additionally, the effects of solder composition on the interfacial IMC growth are evaluated. The results indicate that the Ag addition retards IMC growth upon aging by inhibiting the diffusion of Cu.

Keywords

copper alloys; matrix algebra; solders; Cu₆Sn₅; Sn_3.5Ag-Cu; abnormal grain growth; eutectic interfaces; grain boundary; interfacial IMC growth; interfacial grains; intermetallic compounds; layer-type morphology; preferential growth; pure interfaces; solder interfaces; solder matrix; solid-state aging; Aging; Grain boundaries; Joints; Morphology; Scanning electron microscopy; Soldering; Tin; IMC; abnormal growth; diffusion; lead-free solders;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronic Packaging Technology (ICEPT), 2014 15th International Conference on

Conference_Location

Chengdu

Type

conf

DOI

10.1109/ICEPT.2014.6922854

Filename

6922854