TY - JOUR
T1 - Phase stability and thermal expansion behavior of Cu6Sn 5 intermetallics doped with Zn, Au and in
AU - Zeng, Guang
AU - McDonald, Stuart D.
AU - Gu, Qinfen
AU - Suenaga, Shoichi
AU - Zhang, Yong
AU - Chen, Jianghua
AU - Nogita, Kazuhiro
N1 - Funding Information:
We gratefully acknowledge financial support from the University of Queensland-Nihon Superior collaborative Research Program . PXRD experiments were performed at the Australian Synchrotron Powder Diffraction Beamline (Project ID: AS121/PD/4524 and AS122/PD/4903). The author thanks Mr. J. Read and Dr. D. Mu of The University of Queensland for valuable discussions and sample preparation; and Mr. Z.R. Liu of Hunan University for first principle calculation. The authors acknowledge the facilities, and the scientific and technical assistance, of the Australian Microscopy & Microanalysis Research Facility at the Centre for Microscopy and Microanalysis, The University of Queensland. G. Zengis financially supported by a University of Queensland International (UQI) Scholarship and a China Scholarship Council (CSC) Scholarship .
PY - 2013
Y1 - 2013
N2 - Cu6Sn5 is a critical intermetallic compound in future three-dimensional integrated circuit (3D IC) in micro-electronic packaging and has different crystal structures in the solid state. This paper investigates the effect of Zn, Au and In on the phase stability and thermal expansion behavior of Cu6Sn5 intermetallics over the temperature range of -80°C to 240 °C, using in-situ variable temperature synchrotron powder X-ray diffraction (PXRD), dilatometry and first principles calculations. The results show Zn, Au and In stabilize the equilibrium high temperature hexagonal Cu6Sn5 crystal variant in directly alloyed samples, over the entire range of temperatures investigated. When present in hexagonal Cu 6Sn5, Zn, Au and In atoms preferentially occupied specific Cu or Sn sites as leading to a more thermodynamically stable phase. The stabilization effect of Zn, Au and In was confirmed using PXRD, dilatometry and first principles calculations. The magnitude of thermal expansion and coefficients of thermal expansion (CTEs) were characterized for each addition. The stabilization of the hexagonal Cu6Sn5 structure prevented the discontinuity in volume expansion that occurs with the polymorphic transformation.
AB - Cu6Sn5 is a critical intermetallic compound in future three-dimensional integrated circuit (3D IC) in micro-electronic packaging and has different crystal structures in the solid state. This paper investigates the effect of Zn, Au and In on the phase stability and thermal expansion behavior of Cu6Sn5 intermetallics over the temperature range of -80°C to 240 °C, using in-situ variable temperature synchrotron powder X-ray diffraction (PXRD), dilatometry and first principles calculations. The results show Zn, Au and In stabilize the equilibrium high temperature hexagonal Cu6Sn5 crystal variant in directly alloyed samples, over the entire range of temperatures investigated. When present in hexagonal Cu 6Sn5, Zn, Au and In atoms preferentially occupied specific Cu or Sn sites as leading to a more thermodynamically stable phase. The stabilization effect of Zn, Au and In was confirmed using PXRD, dilatometry and first principles calculations. The magnitude of thermal expansion and coefficients of thermal expansion (CTEs) were characterized for each addition. The stabilization of the hexagonal Cu6Sn5 structure prevented the discontinuity in volume expansion that occurs with the polymorphic transformation.
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U2 - 10.1016/j.intermet.2013.07.012
DO - 10.1016/j.intermet.2013.07.012
M3 - Article
AN - SCOPUS:84882240977
SN - 0966-9795
VL - 43
SP - 85
EP - 98
JO - Intermetallics
JF - Intermetallics
ER -