Abstract
The aim of this study is to investigate the relationship between the inelastic strain range and the thermal fatigue lives of chip size package solder joints with Sn-Pb and Sn-Ag-Cu solder balls. The inelastic strain range was examined by finite element analysis. In both solder joints, the exponential terms in the inelastic strain range term in the Coffin-Manson equation were evaluated as 1.8 - 2.3. These values are very close to the conventional one used in Sn-Pb and the Pb containing solders. The inelastic strain range is almost proportional to the temperature range in the Sn-Pb solder joint. On the contrary, the inelastic strain range is proportional to approximately the square root of the temperature range in the Sn-Ag-Cu solder joint. The deference depends on the change of the stress-strain hysteresis curve in the thermal cycle.
Publisher
Trans Tech Publications, Ltd.
Subject
Mechanical Engineering,Mechanics of Materials,General Materials Science
Reference11 articles.
1. K. C. Norris and A. H. Landzberg: IBM J. Res. Develop., Vol. 13 (1969), p.266.
2. Q. Yu, M. Shiratori, S. Wang, S. Kaneko and T. Ishihara: The Japan Society of Mechanical Engineers, Vol. 64 (1998), p.6.
3. M. Amagai: Microelectronics Reliability, Vol. 39 (1999), p.463.
4. I. Shohji, H. Mori and Y. Orii: Microelectronics Reliability, Vol. 44 (2004), p.269.
5. F. X. Che and J. H. L. Pang: Proc. of 6th Electronics Packaging Technology Conference, (2004), p.787.