Temperature-Dependence Electromigration Failure for Flip-Chip SnAg Solder bumps with 5μm Cu metallization

• Main Authors: Liao, Chih-Jen, 廖志仁
• Other Authors: Chen, Chih
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/nqb386

碩士 === 國立交通大學 === 工學院半導體材料與製程設備學程 === 102 === As the consumer electronic products move toward lightly, thin, short and smaller, we need higher solder input/output joint density. Therefore, the evolution of the bonding technology has moved from “Wire Bonding” to “Flip Chip technology”. Along with the solder bump shrinking and current density increased, electromigration phenomenon had become a crucial reliability concern. Pb-containing solder bump will cause environment pollution, and European Union and the US already forbade to use the Pb-containing solder bumps through the law at Y2006. Thus, the electrical industry is hurry to find the substitute to replace eutectic SnPb solder bump. Pb free solders become the basic requirement for the future electronic product. In recent years, Pb free solder bump research and development as become an important part of the electrical industry. SnAg is one of potential Pb free solder alloys. The Sn-Ag alloy's melting point is about 220°C, and its good mechanical property makes it become a candidate of Pb free solder bump materials. In this study, we investigate the Electromigration behavior stressed by 0.8A at 100℃ and 160℃. The electromigration behavior and the failure mechanism of the bump are monitored at various stages of electromigration. The microstructure of the solder bumps were observed as the bump resistance increased 20%, 100%, 200%, and Opened of its original value. It is found that void formation is mainly responsible for the increase in bump resistance.