Structure and kinetics of Sn whisker growth on Pb-free solder finish

W. J. Choi, T. Y. Lee, King-Ning Tu, N. Tamura, R. S. Celestre, A. A. MacDowell, Y. Y. Bong, L. Nguyen, George T.T. Sheng

研究成果: Article同行評審

62 引文 斯高帕斯(Scopus)


Standard leadframes used in surface mount technology are finished with a layer of eutectic SnPb for passivation and for enhancing solder wetting during reflow. When eutectic SnPb is replaced by Pb-free solder, especially the eutectic SnCu, a large number of Sn whiskers are found on the Pb-free finish. Some of the whiskers are long enough to become shorts between the neighboring legs of the leadframe. How to suppress their growth and how to perform accelerated test of Sn whisker growth are crucial reliability issues in the electronic packaging industry. In this paper, we report the study of spontaneous Sn whisker growth at room temperature on eutectic SnCu and pure Sn finishes. Both compressive stress and surface oxide on Sn are necessary conditions for whisker growth. Structure and stress analyses by using the micro-diffraction in synchrotron radiation are reported. Cross-sectional electron microscopy, with samples prepared by focused ion beam, are included.

頁(從 - 到)628-633
期刊Proceedings - Electronic Components and Technology Conference
出版狀態Published - 1 一月 2002


深入研究「Structure and kinetics of Sn whisker growth on Pb-free solder finish」主題。共同形成了獨特的指紋。