標題: Using nanoindentation to investigate the temperature cycling of Sn-37Pb solders
作者: Wen, Hua-Chiang
Chou, Wu-Ching
Lin, Po-Chen
Jeng, Yeau-Ren
Chen, Chien-Chang
Chen, Hung-Ming
Jiang, Don Son
Cheng, Chun-Hu
機械工程學系
電子物理學系
電子工程學系及電子研究所
Department of Mechanical Engineering
Department of Electrophysics
Department of Electronics Engineering and Institute of Electronics
關鍵字: Intermetallic compounds;Diffusion;Recrystallization;Electron microscopy
公開日期: 1-Nov-2017
摘要: Using nanoindentation and energy dispersive X-ray spectrometry (EDS), we have conducted an investigation into corner failures to elucidate not only the nanomechanical properties of Sn-37Pb solder balls but also the effects of temperature cycling tests (TCTs). We found that the hardness of Sn-37Pb solder balls was greater in central locations [1.18 +/- 0.05 GPa for room-temperature (RT) sample; 1.3 +/- 0.05 GPa for TCT sample], but had standard values in corner locations (>0.2 +/- 0.02 GPa). The modulus increased after the TCTs. Nevertheless, the mechanical properties were closely related to the average area of the alpha-Pb phase. The average area of the Pb-rich region was more stable after the TCTs than that of the RT sample, due to the enhanced mechanical properties of the Sn-37Pb solder, suggesting good reliability. From an analysis of average areas in the RT sample, it appears that the Pb-rich solid solution that formed led to weak Sn-Pb bonds near the corner locations. Electron back scattered diffraction measurements revealed that grains with grain boundaries formed as a result of accelerated TCT cycling. We conclude that Sn-Pb recrystallization was initiated and propagated after the TCTs, followed by propagation to the interfacial region. (C) 2017 Published by Elsevier Ltd.
URI: http://dx.doi.org/10.1016/j.microrel.2017.05.004
http://hdl.handle.net/11536/144058
ISSN: 0026-2714
DOI: 10.1016/j.microrel.2017.05.004
期刊: MICROELECTRONICS RELIABILITY
Volume: 78
起始頁: 111
結束頁: 117
Appears in Collections:Articles