Spectacular epitaxial growth of (Cu,Ni)6Sn5 formed on Ni substrate
Journal
International Microsystems Packaging Assembly and Circuits Technology Conference, 2010 and International 3D IC Conference
ISBN
9781424497836
Date Issued
2010
Author(s)
Chen W.M.
Abstract
The texture as well as epitaxial growth of intermetallic compounds (IMCs) are becoming important issues, due to increases in IMCs-solder ratios in the development of micro-bumping. (Cu, Ni) 6 Sn 5 formed on Ni substrate didn't simply grow in an unexpected manner, but did so, producing a spectacular morphology. Even in the presence of very few Ni atoms dissolved in (Cu, Ni) 6 Sn 5 , a strongly preferential orientation growth was still observed. The crystal orientation relationships between (Cu, Ni) 6 Sn 5 and Ni was recognized as: (12̅0) (Cu, Ni)6Sn5
(11̅1) Ni ; [001] (Cu, Ni)6Sn5
[110] Ni , according to EBSD and TEM analysis. The outcome of this study explicitly demonstrates that the morphology of (Cu, Ni) 6 Sn 5 is determined by the preferred orientation relationship with Ni, and therefore one could predict the morphological texture of (Cu, Ni) 6 Sn 5 , once the crystal orientations of Ni were known. Moreover, because a coherent interface between (Cu, Ni) 6 Sn 5 and Ni was observed, this study also verified that no (Ni, Cu) 3 Sn 4 IMCs had formed at the interface of (Cu, Ni) 6 Sn 5 /Ni.
Type
conference paper