Somidin Flora, Maeno Hiroshi, Tran Xuan Quy, D McDonald Stuart, Mohd Salleh Mohd Arif Anuar, Matsumura Syo, Nogita Kazuhiro
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.
Centre of Excellence Geopolymer and Green Technology, School of Materials Engineering, Universiti Malaysia Perlis, Taman Muhibbah, Arau 02600, Malaysia.
Materials (Basel). 2018 Nov 9;11(11):2229. doi: 10.3390/ma11112229.
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.
通过高压透射电子显微镜（HV-TEM）技术，实现了对单个目标Cu₆Sn₅晶粒在Sn-0.7 wt% Cu焊料和Cu-Cu₃Sn相之间的多晶型转变及其在固态热循环过程中相关结构演变的原位观察。在此，我们表明，从210°C冷却至等温140°C时，单斜η'-Cu₆Sn₅超晶格反射出现在六方η-Cu₆Sn₅衍射图案中。原位实空间成像表明，η'-Cu₆Sn₅对比度图案始于晶界。该方法展示了一种进一步理解实际焊点上多晶型转变行为的新途径。
