Interfacial Reaction in Cu Pillar/Sn Bump Structure during Current Stressing
Cu pillar bump was annealed or current stressed at various current densities. Based on the results of electromigration life time test, the resistance to electromigration of Cu pillar bump was much better than conventional solder bump. Also, intermetallic compounds (IMCs) growth behaviors were investigated by in-situ scanning electron microscopy (SEM) observation. Only Cu6Sn5 was observed in the Cu pillar/Sn interface after reflow. However, Cu3Sn formed and grew at Cu pillar/Cu6Sn5 interface with increasing annealing and stressing time. The growth kinetics of total (Cu6Sn5 + Cu3Sn) IMC changed when all Sn phases in Cu pillar bump were exhausted. The complete consumption time of Sn phase in electromigration condition was faster than that in annealing condition. Kirkendall voids, which would be detrimental to the reliability of Cu pillar bump, were observed at both Cu3Sn/Cu pillar and Cu3Sn/Cu under bump metallization interfaces.
Myeong-Hyeok Jeong Jae-Won Kim Gi-Tae Lim Byoung-Joon Kim Kiwook Lee Jaedong Kim Young-Chang Joo Young-Bae Park
School of Materials Science and Engineering, Andong National University, Andong, 760-749, Korea School of Materials Science and Engineering, Seoul National University, Seoul, 151-744, Korea Amkor Technology Korea Inc, Seoul, 133-706, Korea
国际会议
北京
英文
782-785
2009-08-10（万方平台首次上网日期，不代表论文的发表时间）