tin whisker mitigation by means of a post-electroplating electrochemical oxidation treatment3.pdf (1.49 MB)
Tin whisker mitigation by means of a post-electroplating electrochemical oxidation treatment
journal contributionposted on 2015-12-11, 15:49 authored by Dan Haspel, Mark Ashworth, Liang Wu, Geoffrey Wilcox, Roger J. Mortimer
There are very few studies that have investigated directly the effect of an oxide film on tin whisker growth, since the ‘cracked oxide theory’ was proposed by Tu in 19941. The current study has investigated the effect of an electrochemically produced oxide on tin whisker growth, for both Sn-Cu electrodeposits on Cu and pure Sn electrodeposits on brass. X-ray photoelectron spectroscopy (XPS) has been used to investigate the effect of the applied electrochemical oxidation potential on the oxide film thickness. Focused ion beam (FIB) has been used to prepare cross sections from electrodeposited samples to investigate the influence of the electrochemically formed oxide film on deposit microstructure during long-term room temperature storage. The XPS studies show that the thickness of electrochemically formed oxide film is directly influenced by the applied potential and the total charge passed. Whisker growth studies show that the electrochemical oxidation treatment mitigates whisker growth for both Sn-Cu electrodeposits on Cu and pure Sn electrodeposits on brass. For Sn electrodeposits on brass, the electrochemically formed oxide greatly reduces both the formation of zinc oxide at the surface and the formation of intermetallic compounds, which results in the mitigation of tin whisker growth. For Sn-Cu electrodeposits on Cu, the electrochemically formed oxide has no apparent effect on intermetallic compound formation and acts simply as a physical barrier to hinder tin whisker growth.
This paper was supported by the UK EPSRC Innovative Electronics Manufacturing Research Centre through the WHISKERMIT programme
- Aeronautical, Automotive, Chemical and Materials Engineering
Published inTransactions of the IMF
CitationHASPEL, D. ...et al., 2015. Tin whisker mitigation by means of a post-electroplating electrochemical oxidation treatment. Transactions of the Institute of Metal Finishing , 93(6), pp.332-341.
Publisher© Maney Publishing. Published on behalf of the Institute of Metal Finishing (IMF)
- AM (Accepted Manuscript)
Publisher statementThis work is made available according to the conditions of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) licence. Full details of this licence are available at: https://creativecommons.org/licenses/by-nc-nd/4.0/
NotesThis is an Accepted Manuscript of an article published by Taylor & Francis in Transactions of the Institute of Metal Finishing on 11 Jan 2016, available online: http://www.tandfonline.com/10.1080/00202967.2015.1117258.