biostudies-literature00620Unknown15(2)Tan XFThe University of QueenslandMinistry of Education, Culture, Sports, Science and TechnologyKyushu UniversityAustralian Research CouncilThe complex reaction between liquid solder alloys and solid substrates has been studied ex-situ in a few studies, utilizing creative setups to "freeze" the reactions at different stages during the reflow soldering process. However, full understanding of the dynamics of the process is difficult due to the lack of direct observation at micro- and nano-meter resolutions. In this study, high voltage transmission electron microscopy (HV-TEM) is employed to observe the morphological changes that occur in Cu₆Sn₅ between a Sn-3.0 wt%Ag-0.5 wt%Cu (SAC305) solder alloy and a Cu substrate in situ at temperatures above the solidus of the alloy. This enables the continuous surveillance of rapid grain boundary movements of Cu₆Sn₅ during soldering and increases the fundamental understanding of reaction mechanisms in solder solid/liquid interfaces.Materials (Basel, Switzerland)https://www.ebi.ac.uk/biostudies/studies/S-EPMC8780827biostudies-literatureIn Situ Observation of Liquid Solder Alloys and Solid Substrate Reactions Using High-Voltage Transmission Electron Microscopy.PMC8780827Nihon Superior ProjectUQ-KU projectProgress 100 programJPMXP09-A-17-KU-224DP200101949Maeno HMcDonald SDMatsumura SNogita KTan XFBermingham MJSomidin F62falseIn Situ Observation of Liquid Solder Alloys and Solid Substrate Reactions Using High-Voltage Transmission Electron Microscopy.The complex reaction between liquid solder alloys and solid substrates has been studied ex-situ in a few studies, utilizing creative setups to "freeze" the reactions at different stages during the reflow soldering process. However, full understanding of the dynamics of the process is difficult due to the lack of direct observation at micro- and nano-meter resolutions. In this study, high voltage transmission electron microscopy (HV-TEM) is employed to observe the morphological changes that occur in Cu₆Sn₅ between a Sn-3.0 wt%Ag-0.5 wt%Cu (SAC305) solder alloy and a Cu substrate in situ at temperatures above the solidus of the alloy. This enables the continuous surveillance of rapid grain boundary movements of Cu₆Sn₅ during soldering and increases the fundamental understanding of reaction mechanisms in solder solid/liquid interfaces.2022-01-01T00:00:00Z2022 Jan2022-02-11T16:01:39.228Z2022-02-11T16:01:39.228ZS-EPMC87808273505722610.3390/ma15020510