A metastable phase of tin in 3D integrated circuit solder microbumps. (June 2015)

• Record Type: Journal Article
• Authors: Liu, Yingxia; Tamura, Nobumichi; Kim, Dong Wook; Gu, Sam; Tu, K.N.
• Is Part Of: Scripta materialia. Volume 102(2015)
• Page Start: 39
• Page End: 42
• Publication Date: 2015-06
• Subjects: Lead-free solder -- Metastable phases -- Electronic packaging -- Joining; Materials -- Periodicals; Metallurgy -- Periodicals; Metalen; Legeringen; Materiaalkunde; Metals, metalworking and machinery industries; Metals; Electronic journals; 620.11
• DOI: 10.1016/j.scriptamat.2015.02.009
• Languages: English
• ISSNs: 1359-6462

Abstract

Graphical abstract: Abstract : A metastable phase of Sn has been found to co-exist with β-Sn in Pb-free SnAg microbumps in 3D integrated circuit technology. Synchrotron microbeam X-ray diffraction, high-resolution TEM imaging and selected-area electron diffraction were used to confirm the metastable phase, which has an orthorhombic lattice, with lattice parameter a = 0.635 nm, b = 0.639 nm, and c = 1.147 nm. Its composition is Sn containing a few percent of Ni. A higher rate of nucleation might have enabled its formation.