Affiliations 

  • 1 Nihon Superior Centre for the Manufacture of Electronic Materials (NS CMEM), School of Mechanical and Mining Engineering, The University of Queensland, Brisbane QLD 4072, Australia. f.somidin@uq.net.au
  • 2 The Ultramicroscopy Research Center, Kyushu University, Fukuoka 819-0395, Japan. maeno@hvem.kyushu-u.ac.jp
  • 3 Department of Applied Quantum Physics and Nuclear Engineering, Kyushu University, Fukuoka 819-0395, Japan. xuan.tran@nucl.kyushu-u.ac.jp
  • 4 Nihon Superior Centre for the Manufacture of Electronic Materials (NS CMEM), School of Mechanical and Mining Engineering, The University of Queensland, Brisbane QLD 4072, Australia. s.mcdonald1@uq.edu.au
  • 5 Centre of Excellence Geopolymer and Green Technology, School of Materials Engineering, Universiti Malaysia Perlis, Taman Muhibbah, Arau 02600, Malaysia. arifanuarsalleh@gmail.com
  • 6 The Ultramicroscopy Research Center, Kyushu University, Fukuoka 819-0395, Japan. syo@nucl.kyushu-u.ac.jp
  • 7 Nihon Superior Centre for the Manufacture of Electronic Materials (NS CMEM), School of Mechanical and Mining Engineering, The University of Queensland, Brisbane QLD 4072, Australia. k.nogita@uq.edu.au
Materials (Basel), 2018 Nov 09;11(11).
PMID: 30423946 DOI: 10.3390/ma11112229

Abstract

In-situ observations of the polymorphic transformation in a single targeted Cu₆Sn₅ grain constrained between Sn-0.7 wt % Cu solder and Cu-Cu₃Sn phases and the associated structural evolution during a solid-state thermal cycle were achieved via a high-voltage transmission electron microscope (HV-TEM) technique. Here, we show that the monoclinic η'-Cu₆Sn₅ superlattice reflections appear in the hexagonal η-Cu₆Sn₅ diffraction pattern upon cooling to isothermal 140 °C from 210 °C. The in-situ real space imaging shows that the η'-Cu₆Sn₅ contrast pattern is initiated at the grain boundary. This method demonstrates a new approach for further understanding the polymorphic transformation behavior on a real solder joint.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.