TY - GEN
T1 - Anti-tarnishing evaluations of silver solid solution phase with indium
AU - Huo, Yongjun
AU - Lee, Chin C.
N1 - Publisher Copyright:
© 2015 IEEE.
PY - 2015/7/15
Y1 - 2015/7/15
N2 - Pure silver or sterling silver can be tarnished under ordinary atmospheric conditions after a long period of time, or can be easily tarnished under severe environment with high concentration of hydrogen sulfide, sulfur gas, or sulfur dioxide. In electronic packaging, the epoxy molding compounds are gas permeable so that those corrosive gases could penetrate into plastic encapsulation. Therefore, silver-based interconnections will not be widely accepted if the issue of silver tarnishing cannot be addressed properly. In this paper, the authors present an alternative method to reduce the chemical reaction rate between silver and sulfur element containing gases by introducing silver solid solution phase with indium. A brief summary of preparation of the homogeneous silver solid solution phase with indium will be illustrated. The X-ray diffraction (XRD) patterns and scanning electron microscope/energy dispersive X-ray spectroscopy (SEM/EDX) results are shown in the paper to verify the chemical composition of silver solid solution phase with indium samples. In the following sections, both qualitative and quantitative experimental results of the chemical reactions between silver solid solution phase with indium samples and corrosive gases will be demonstrated and discussed with pure silver samples in comparison. According to experimental results of the anti-tarnishing evaluations, the reaction rate between silver and corrosive gases can be largely reduced without changing the appearance and color of the surface of silver samples. Finally, the impacts and implications of this research result to electronic packaging industry will be illuminated.
AB - Pure silver or sterling silver can be tarnished under ordinary atmospheric conditions after a long period of time, or can be easily tarnished under severe environment with high concentration of hydrogen sulfide, sulfur gas, or sulfur dioxide. In electronic packaging, the epoxy molding compounds are gas permeable so that those corrosive gases could penetrate into plastic encapsulation. Therefore, silver-based interconnections will not be widely accepted if the issue of silver tarnishing cannot be addressed properly. In this paper, the authors present an alternative method to reduce the chemical reaction rate between silver and sulfur element containing gases by introducing silver solid solution phase with indium. A brief summary of preparation of the homogeneous silver solid solution phase with indium will be illustrated. The X-ray diffraction (XRD) patterns and scanning electron microscope/energy dispersive X-ray spectroscopy (SEM/EDX) results are shown in the paper to verify the chemical composition of silver solid solution phase with indium samples. In the following sections, both qualitative and quantitative experimental results of the chemical reactions between silver solid solution phase with indium samples and corrosive gases will be demonstrated and discussed with pure silver samples in comparison. According to experimental results of the anti-tarnishing evaluations, the reaction rate between silver and corrosive gases can be largely reduced without changing the appearance and color of the surface of silver samples. Finally, the impacts and implications of this research result to electronic packaging industry will be illuminated.
UR - http://www.scopus.com/inward/record.url?scp=84942080016&partnerID=8YFLogxK
U2 - 10.1109/ECTC.2015.7159905
DO - 10.1109/ECTC.2015.7159905
M3 - Conference contribution
AN - SCOPUS:84942080016
T3 - Proceedings - Electronic Components and Technology Conference
SP - 2180
EP - 2187
BT - 2015 IEEE 65th Electronic Components and Technology Conference, ECTC 2015
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 2015 65th IEEE Electronic Components and Technology Conference, ECTC 2015
Y2 - 26 May 2015 through 29 May 2015
ER -