Interfacial Reactions of Sn-Ag-Cu Solders in Ball Grid Array Packages

• Main Authors: MingDa Cheng, 鄭明達
• Other Authors: T.H. Chuang
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/65231264520572045862

博士 === 國立臺灣大學 === 材料科學與工程學研究所 === 92 === Due to the hazard of lead for human bodies and environments, lead-free solders are started to investigate. Among many lead-free solders, a series of Sn-Ag-Cu alloys is considered one of the most potential materials so we focus on the six various compositions of Sn-Ag-Cu solders, such as Sn-3.8Ag-0.7Cu, Sn-3Ag-0.5Cu, Sn-4Ag-0.5Cu, Sn-2Ag-6Cu, Sn-4Ag-5Cu and Sn-20In-2Ag-0.5Cu, studying the interfacial reactions in ball grid array packages(BGA packages). In these studies, two kinds of BGA substrates with Au/Ni/Cu and Ag/Cu surface finishes are used and we would like to know the effects of different Sn-Ag-Cu solders on solder joints in the interfacial reactions. Results reveal that the few differences of solder compositions can affect the morphology, type and growth rate of intermetallics. Two kinds of surface-finish substrates have various influences on solder joints. And studies show that the joints with Au/Ni/Cu surface finishes are better than the joints with Ag/Cu ones.