Liquid-state interfacial reactions between Sn-Ag-Cu-Fe composite solders and Cu substrate

Author

Liu, Xiaoying ; Zhao, Yanhui ; Huang, Mingliang ; Wu, C.M.L. ; Wang, Lai

Author_Institution

Dept. of Mater. Eng., Dalian Univ. of Technol., Dalian, China

fYear

2009

fDate

10-13 Aug. 2009

Firstpage

687

Lastpage

690

Abstract

Growth kinetics and interfacial morphologies of the intermetallic compound (IMCs) between Sn-3Ag-0.5Cu-xFe(0, 0.5wt.%, 1wt.%) composite solders and Cu substrates were investigated by reflowing for different durations at 250degC. Fe particles were deposited quickly in the vicinity of IMCs of the as-reflow samples due to the higher density of Fe than that of Sn-Ag-Cu. They formed a region about 30mum wide where the volume percentage of Fe particles could reach 19%. The isothermal equation of chemical reaction and phase diagrams is used to explain the effect of Fe on the growth kinetics of IMCs under liquid-state conditions. It is found that Fe can effectively retard the growth of Cu₆Sn₅ and Cu₃Sn during liquid-state aging and reduce the size of Cu₆Sn₅ particles. Some local small cracks were observed in the Cu₆Sn₅ particles near interfaces of SAC solder alloys after reflowing for about five minutes. Such cracks were found in the other composite solders only thirty minutes reflow.

Keywords

chemical reactions; composite materials; copper; copper alloys; cracks; interface phenomena; iron alloys; phase diagrams; silver alloys; solders; surface chemistry; tin alloys; Cu; Cu substrate; Fe particle; Sn-Ag-Cu-Fe-Cu; chemical reaction; composite solders; cracks; growth kinetics; interfacial morphology; isothermal equation; liquid state aging; liquid-state interfacial reactions; phase diagram; temperature 250 degC; Aging; Chemicals; Copper alloys; Equations; Intermetallic; Iron; Isothermal processes; Kinetic theory; Morphology; Tin;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronic Packaging Technology & High Density Packaging, 2009. ICEPT-HDP '09. International Conference on

Conference_Location

Beijing

Print_ISBN

978-1-4244-4658-2

Electronic_ISBN

978-1-4244-4659-9

Type

conf

DOI

10.1109/ICEPT.2009.5270662

Filename

5270662