naa a22 4500 510804853 CHVBK 20180411083412.0 cr unu---uuuuu 180411e20130201xx s 000 0 eng 10.1007/s11664-012-2267-3 doi (NATIONALLICENCE)springer-10.1007/s11664-012-2267-3 Altering the Mechanical Properties of Sn Films by Alloying with Bi: Mimicking the Effect of Pb to Suppress Whiskers [Elektronische Daten] [Nitin Jadhav, Maureen Williams, Fei Pei, Gery Stafford, Eric Chason] Stress is believed to be the main driving force for whisker formation in Sn coatings on Cu. This suggests that whiskering can be suppressed by enhancing stress relaxation in the Sn layer, which is believed to be the reason why Sn-Pb alloys do not form whiskers. However, Pb is no longer acceptable for use in electronics manufacturing. As an alternative, we used pulsed plating to create Sn-Bi coatings with an equiaxed microstructure similar to that of Sn-Pb alloys. An optical wafer curvature technique was used to measure stress relaxation kinetics in Sn, Sn-Pb and Sn-Bi alloy thin films during thermal cycles. The results show that Sn-Bi films have significantly enhanced stress relaxation relative to pure Sn films. Comparison between Sn-Bi samples with equiaxed and columnar microstructures shows that both microstructure and alloy composition play a role in enhancing the stress relaxation. TMS, 2012 SnBi nationallicence pulsed plating nationallicence whisker nationallicence Pb-free solder nationallicence mechanical properties of Sn and Bi alloy Sn thin films nationallicence thermal stress nationallicence Jadhav Nitin School of Engineering, Brown University, 02912, Providence, RI, USA aut Williams Maureen National Institute of Standards and Technology, 20899, Gaithersburg, MD, USA aut Pei Fei School of Engineering, Brown University, 02912, Providence, RI, USA aut Stafford Gery National Institute of Standards and Technology, 20899, Gaithersburg, MD, USA aut Chason Eric School of Engineering, Brown University, 02912, Providence, RI, USA aut Journal of Electronic Materials Springer US; http://www.springer-ny.com 42/2(2013-02-01), 312-318 0361-5235 42:2<312 2013 42 11664 https://doi.org/10.1007/s11664-012-2267-3 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11664-012-2267-3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Jadhav Nitin School of Engineering, Brown University, 02912, Providence, RI, USA aut NATIONALLICENCE 700 1- Williams Maureen National Institute of Standards and Technology, 20899, Gaithersburg, MD, USA aut NATIONALLICENCE 700 1- Pei Fei School of Engineering, Brown University, 02912, Providence, RI, USA aut NATIONALLICENCE 700 1- Stafford Gery National Institute of Standards and Technology, 20899, Gaithersburg, MD, USA aut NATIONALLICENCE 700 1- Chason Eric School of Engineering, Brown University, 02912, Providence, RI, USA aut NATIONALLICENCE 773 0- Journal of Electronic Materials Springer US; http://www.springer-ny.com 42/2(2013-02-01), 312-318 0361-5235 42:2<312 2013 42 11664 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer