Interfacial Reactions of Wire-bonded Gold Bumps with Aluminu Pads in Flip Chip Assembly

• Main Authors: Yu-Chih Liu, 劉育志
• Other Authors: 莊東漢
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/38919778417361813933

碩士 === 國立臺灣大學 === 材料科學與工程學研究所 === 95 === The effort of this study is to comprehend the interfacial reaction of gold bump and aluminum pad. Thermosonic bonding combines the ultrasonic bonding and thermo-compression bonding. In the process of bonding, substrates maintain 150~250℃. This bonding temperature affects the growth of IMC, especially when the bonding lasts longer. Furthermore, Pb-free technology needs higher process temperatures which may cause joints failure. In this study, we will investigate Au/Au joints and Au/Al joints. According to this study, Au/Au joints all break in the gold solder and their strength doesn’t change with time. However, there are different sorts of failure modes in Au/Al joints. These failure modes affect the ball shear strength. Au/Al joints break in the lower temperature due to the cratering effect and break in the higher temperature due to the Kirkendall voids. In this research, we use TEM , SEM , OM and AES to investigate intermetallic compound .