Title :
Cross-interaction effect in the Ni/Sn/Cu solder joints
Author :
Tseng, H.W. ; Wang, S.J. ; Liu, C.Y.
Author_Institution :
Dept. of Chem. Eng. & Mater. Eng., Nat. Central Univ., Jhongli, Taiwan
Abstract :
The mutual interaction between Sn/Ni and Sn/Cu interfacial reactions in a Ni/Sn/Cu sandwich solder joint structure has been discussed in this present work. The major interfacial reaction product on the Sn/Cu interface was Cu6Sn5 phase, while on the Sn/Ni interface, a ternary (Cu,Ni)6Sn5 compound layer was formed, instead of the typical Ni-Sn compound phase. On the other hand, an asymmetrical solder microstructure was observed in the Ni/Sn/Cu solder joint. The asymmetrical solder microstructure resulted from the Cu concentration gradient along the Ni/Sn/Cu solder joint. Mechanical tensile tests showed that the mechanical property of the Ni/Sn/Cu solder joint is highly correlated with the asymmetrical solder microstructure.
Keywords :
copper alloys; interface structure; nickel alloys; solders; tensile testing; tin alloys; Cu6Ni6Sn5; Ni-Sn-Cu; asymmetrical solder microstructure; concentration gradient; cross-interaction effect; interfacial reaction product; mechanical property; mechanical tensile tests; mutual interaction; sandwich solder joint structure; ternary compound layer; Chemical engineering; Electronics packaging; Joining materials; Mechanical factors; Microstructure; Morphology; Scanning electron microscopy; Soldering; Testing; Tin; Cross-interaction; Packaging; UBM;
Conference_Titel :
Electronics Packaging Technology Conference, 2009. EPTC '09. 11th
Conference_Location :
Singapore
Print_ISBN :
978-1-4244-5099-2
Electronic_ISBN :
978-1-4244-5100-5
DOI :
10.1109/EPTC.2009.5416529
