电子封装中Au80Sn20焊料与镀层之间的相互作用及组织演变

Interfacial Interactions and Microstructure Evolution between Au80Sn20 Solder and Metallization Film in Electronic Packaging

电子元器件常通过镀层提高可焊性,主要包括Au、Ni、Cu、Au/Ni(Ti)、Au/Pt/Ti、Au/TiW等。Au80Sn20焊料是电子封装中的常用材料,文中总结了AuSn焊料与镀层之间的相互作用及组织演变。润湿性主要取决于AuSn焊料表面的氧化以及镀层在AuSn焊料中的溶解速度,Cu、Pt的原子结构与Au相似,以置换原子的形式溶解在AuSn焊料中,Ti与AuSn焊料之间的润湿性较差。AuSn焊料与镀层发生界面反应生成(Ni,Au)3Sn2、ζ-(Au,Cu)5Sn、Au5Sn、Ni3Sn4等金属间化合物(IMC),IMC的形成和组织演变与焊点结构、工艺参数、服役条件等因素有关。

Metallization films have been widely used to improve the solderability of electronic components.Types of metallization films are mainly Au,Ni,Cu,Au/Ni（Ti）,Au/Pt/Ti,Au/TiW and so on.Au80Sn20 solder is commonly used in electronic packaging.Interfacial interactions and microstructure evolution between AuSn solder and metallization films are summarized in this paper.Wettability mainly depends on the oxidation of the surface of AuSn solder and the dissolution speed of metallization films in molten AuSn solder.Cu and Pt dissolve in AuSn solder in the form of substitutional atom due to their atomic structures are similar to Au.The wettability between Ti and AuSn solder is poor.Interfacial reaction occurs between AuSn solder and metallization films with the formation of intermetallic compound（IMC）including（Ni,Au）3Sn2,ζ-（Au,Cu）5Sn,Au5 Sn,Ni3Sn4and so on.The formation and microstructure evolution of IMC are related to factors such as solder joint structure,technological parameters and working condition.