Growth inhibition of interfacial intermetallic compounds by pre-coating oriented Cu6Sn5 grains on Cu substrates

Abstract

An effective method for inhibiting the growth of interfacial intermetallic compounds during solid-state aging has been proposed in this study. Pre-tinned Cu substrates containing oriented interfacial Cu6Sn5 grains were prepared and reacted with a low-Ag Pb-free solder. The results show that the initial oriented interfacial grains were retained after the subsequent reflow. In addition, the presence of the oriented grains accelerated their orientation concentration and significantly affected the ultimate orientation distribution range during solid-state aging. As a result, the growth of the interfacial intermetallic compounds was inhibited due to the slower diffusion of Sn species through the solder/substrate interface. (C) 2017 Elsevier B.V. All rights reserved.