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Indexed by:会议论文

Date of Publication:2015-08-11

Included Journals:EI、CPCI-S、Scopus

Page Number:1263-1266

Key Words:solder joint; thermomigration; inteifacial reaction; intermetallic Compound

Abstract:The diffusion behavior of Cu and Ni atoms undergoing liquid-solid thermomigration in Cu/Sn/Cu and Cu/Sn/Ni solder joints was investigated under the temperature gradients of 136.5 degrees C/cm and 154.0 degrees C/cm at 250 degrees C, respectively. Asymmetrical growth of the interfacial IMCs was observed in the Cu/Sn/Cu solder joints, i.e., the IMCs at the cold end were much thicker than those at the hot end. The Cu-Ni cross-solder interaction occurred in the Cu/Sn/Ni solder joints during retlow on hot plate. Cu and Ni atoms arrived to the opposite sides under the concentration gradients, resulting in the formation of (Cux, Ni1-x)(6) Sns IMCs at both interfaces. The interfacial rewaction was accelerated by the combined effect of Cu concentration gradient and thermomigration. While in Cu/Sn/Cu solder joints, the thermomigration process was weakened by Cu concentration gradient. As a result, the IMCs layers at both cold and hot ends in Cu/SnlNi solder joints were thicker than those in Cu/Sn/Cu solder joints after the same retlow time.