Y. Sakamoto , S. Ishihara , K. Masuda , W. Yamazaki , M. Shimura
{"title":"Study on changes in intermetallic compounds and whisker formation over time in Sn/Cu plating","authors":"Y. Sakamoto , S. Ishihara , K. Masuda , W. Yamazaki , M. Shimura","doi":"10.1016/j.mtla.2024.102290","DOIUrl":null,"url":null,"abstract":"<div><div>In Sn/Cu plating, whiskers are formed because of the formation of intermetallic compounds (IMCs) at the Sn/Cu interface and along the Sn grain boundaries. Many previous studies have focused on the mechanism of whisker formation and the change in whisker density over time. However, only a few studies have focused on the formation and growth behavior of IMCs and the correlation between IMCs and whiskers. Furthermore, no studies have quantitatively investigated the time-dependent changes in the formation and growth behavior of IMCs and whiskers using mathematical formulas. In this study, Sn/Cu plating was applied to a 7–3 brass substrate, and the formation and growth of IMCs at the Sn/Cu interface and the behavior of whisker formation were studied. An approximate equation was derived based on the reaction kinetics to quantitatively express the time-dependent changes in both parameters. Three differences were observed between the formation behaviors of IMCs and whiskers. First, no incubation time t<sub>th</sub> was observed for IMC formation, but it was for whiskers. Second, the whisker density increased until t = 10 d and then saturated. However, the IMC density increased until t = 70 d and then became saturated. Third, the IMC density in the cross section is 7–10 times higher than the whisker density, and the rate constant of the IMCs is smaller than that of the whiskers.</div></div>","PeriodicalId":47623,"journal":{"name":"Materialia","volume":"38 ","pages":"Article 102290"},"PeriodicalIF":3.0000,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Materialia","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2589152924002874","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
In Sn/Cu plating, whiskers are formed because of the formation of intermetallic compounds (IMCs) at the Sn/Cu interface and along the Sn grain boundaries. Many previous studies have focused on the mechanism of whisker formation and the change in whisker density over time. However, only a few studies have focused on the formation and growth behavior of IMCs and the correlation between IMCs and whiskers. Furthermore, no studies have quantitatively investigated the time-dependent changes in the formation and growth behavior of IMCs and whiskers using mathematical formulas. In this study, Sn/Cu plating was applied to a 7–3 brass substrate, and the formation and growth of IMCs at the Sn/Cu interface and the behavior of whisker formation were studied. An approximate equation was derived based on the reaction kinetics to quantitatively express the time-dependent changes in both parameters. Three differences were observed between the formation behaviors of IMCs and whiskers. First, no incubation time tth was observed for IMC formation, but it was for whiskers. Second, the whisker density increased until t = 10 d and then saturated. However, the IMC density increased until t = 70 d and then became saturated. Third, the IMC density in the cross section is 7–10 times higher than the whisker density, and the rate constant of the IMCs is smaller than that of the whiskers.
期刊介绍:
Materialia is a multidisciplinary journal of materials science and engineering that publishes original peer-reviewed research articles. Articles in Materialia advance the understanding of the relationship between processing, structure, property, and function of materials.
Materialia publishes full-length research articles, review articles, and letters (short communications). In addition to receiving direct submissions, Materialia also accepts transfers from Acta Materialia, Inc. partner journals. Materialia offers authors the choice to publish on an open access model (with author fee), or on a subscription model (with no author fee).