Abstract
The effect of flip chip bonding parameters on formation of intermetallic compounds (IMCs) between Au stud bumps and Sn-3.5Ag solder was investigated. In this study, flip chip bonding temperature was performed at <TEX>$260^{\circ}C$</TEX> and <TEX>$300^{\circ}C$</TEX> with various bonding times of 5, 10, and 20 sec. AuSn, <TEX>$AuSn_2$</TEX> and <TEX>$AuSn_4$</TEX> IMCs were formed at the interface of joints and (Au, Cu)<TEX>$_6Sn_5$</TEX> IMC was observed near Cu pad side in the joint. At bonding temperature of <TEX>$260^{\circ}C$</TEX>, <TEX>$AuSn_4$</TEX> IMC was dominant in the joint compared to other Au-Sn IMCs as bonding time increased. At bonding temperature of <TEX>$300^{\circ}C$</TEX>, <TEX>$AuSn_2$</TEX> IMC clusters, which were surrounded by <TEX>$AuSn_4$</TEX> IMC, were observed in the solder joint due to fast diffusivity of Au to molten solder with increased bonding temperature. Bond strength of Au stud bump joined with Sn-3.5Ag solder was about 23 gf/bump and fracture mode of the joint was intergranular fracture between <TEX>$AuSn_2$</TEX> and <TEX>$AuSn_4$</TEX> IMCs regardless bonding conditions.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
