naa a22 4500 510803563 CHVBK 20180411083406.0 cr unu---uuuuu 180411e20130301xx s 000 0 eng 10.1007/s11664-012-2380-3 doi (NATIONALLICENCE)springer-10.1007/s11664-012-2380-3 Mechanisms of Creep Deformation in Pure Sn Solder Joints [Elektronische Daten] [K. Lee, J. Morris Jr., Fay Hua] The work reported here concerns the creep of pure Sn solder joints with Cu metallization (Cu||Sn||Cu). Steady-state creep tests in shear are combined with electron backscatter diffraction (EBSD) analysis of the evolution of the microstructure during creep to clarify the deformation mechanism and the nature of the microstructural evolution. The creep behavior of the joint changes significantly with temperature. At low temperature (65°C), two distinct creep mechanisms are observed. Low-stress creep is apparently dominated by grain boundary sliding, as evidenced by the low stress exponent (n≈4), low activation energy (Q≈42kJ/mole), and significant grain rotation during creep. High-stress creep is dominated by bulk deformation processes, evidenced by a high stress exponent (n≈9), an activation energy like that for bulk diffusion (Q≈70kJ/mole), and a relatively fixed microstructure. At high temperature all aspects of its behavior are consistent with deformation by bulk creep mechanisms; the stress exponent and activation energy are high (n≈5 to 7, Q≈96kJ/mole), and despite significant grain coarsening, the microstructure retains (and strengthens) a fixed [001] texture. The results suggest that a "segmented” constitutive equation of Dorn type is most suitable for the low-temperature behavior, while a "hyperbolic” constitutive equation may be preferable at high temperature. TMS, 2012 Tin nationallicence creep mechanism nationallicence Pb-free solder nationallicence Lee K. Department of Materials Science and Engineering, University of California, 94720, Berkeley, CA, USA aut Morris Jr. J. Department of Materials Science and Engineering, University of California, 94720, Berkeley, CA, USA aut Hua Fay Intel Corporation, 95054, Sunnyvale, CA, USA aut Journal of Electronic Materials Springer US; http://www.springer-ny.com 42/3(2013-03-01), 516-526 0361-5235 42:3<516 2013 42 11664 https://doi.org/10.1007/s11664-012-2380-3 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11664-012-2380-3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Lee K. Department of Materials Science and Engineering, University of California, 94720, Berkeley, CA, USA aut NATIONALLICENCE 700 1- Morris Jr J. Department of Materials Science and Engineering, University of California, 94720, Berkeley, CA, USA aut NATIONALLICENCE 700 1- Hua Fay Intel Corporation, 95054, Sunnyvale, CA, USA aut NATIONALLICENCE 773 0- Journal of Electronic Materials Springer US; http://www.springer-ny.com 42/3(2013-03-01), 516-526 0361-5235 42:3<516 2013 42 11664 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer