Interfacial microstructure of Pb-free and Pb-Sn solder balls in the ball-grid array package |
| |
Authors: | Chin-Su Chi Hen-So Chang Ker-Chang Hsieh C. L. Chung |
| |
Affiliation: | (1) Institute of Materials Science and Engineering, National Sun Yat-sen University, Kaohsiung, Taiwan, Republic of China;(2) Assy. Tech. Dev. Div., ChipMOS Technologies Inc., Tainan, Taiwan, Republic of China |
| |
Abstract: | Ball-grid array (BGA) samples were aged at 155°C up to 45 days. The formation and the growth of the intermetallic phases at the solder joints were investigated. The alloy compositions of solder balls included Sn-3.5Ag-0.7Cu, Sn-1.0Ag-0.7Cu, and 63Sn-37Pb. The solder-ball pads were a copper substrate with an Au/Ni surface finish. Microstructural analysis was carried out by electron microprobe. The results show that a ternary phase, (Au,Ni)Sn4, formed with Ni3Sn4 in the 63Sn-37Pb solder alloy and that a quaternary intermetallic phase, (Au,Ni)2Cu3Sn5, formed in the Sn-Ag-Cu solder alloys. The formation mechanism of intermetallic phases was associated with the driving force for Au and Cu atoms to migrate toward the interface during aging. |
| |
Keywords: | Sn-3.5Ag solder BGA reliability interface reaction |
本文献已被 SpringerLink 等数据库收录! |
|