Title :
Solid state growth kinetics of complex intermetallics in the Pb-free ball grid array (BGA) solder joint for MEMS packaging
Author :
Alam, M.O. ; Dan, Yang ; Wu, B.Y. ; Chan, Y.C. ; Rufer, L. ; Bailey, C.
Author_Institution :
Dept. of Electron. Eng., City Univ. of Hong Kong, Kowloon
Abstract :
Interfacial reaction and reliability related problems of the solder joint for both advanced electronic packaging applications and MEMS packaging applications are becoming crucial with the downscaling of the device size. In this study, the solid state interfacial reaction between the BGA Sn-3.5%Ag-0.5%Cu solder and the Au/Ni/Cu bond pad for MEMS applications was investigated at 150-200degC, for different time period ranging from 0 hrs to 400 hrs and compared with that of the Sn-3.5%Ag solder. It was found that 0.5 wt% Cu addition plays a strong role on the interfacial reaction products and the reaction kinetics - especially, at a high temperature near the melting point of the solder alloy. While the Sn-3.5%Ag solder reacts with the Au/Ni/Cu metallization simply by forming only one binary intermetallic compound (BIMC), the Sn-3.5%Ag-0.5%Cu solder reacts in a completely different manner
Keywords :
ball grid arrays; copper; copper alloys; gold; metallisation; micromechanical devices; nickel; silver alloys; solders; tin alloys; 0 to 400 hrs; 150 to 200 C; Au-Ni-Cu; MEMS packaging; SnAgCu; ball grid array solder joint; binary intermetallic compound; complex intermetallics; interfacial reaction; interfacial reliability; melting point; reaction kinetics; solder alloy; solid state growth kinetics; Bonding; Copper alloys; Electronics packaging; Gold; Intermetallic; Kinetic theory; Micromechanical devices; Soldering; Solid state circuits; Temperature;
Conference_Titel :
Electronics Packaging Technology Conference, 2006. EPTC '06. 8th
Conference_Location :
Singapore
Print_ISBN :
1-4244-0664-1
Electronic_ISBN :
1-4244-0665-X
DOI :
10.1109/EPTC.2006.342717
