RC69.pdf (2.15 MB)
Download file

Stability of Ni3P and its effect on the interfacial reaction between electroless Ni-P and molten tin

Download (2.15 MB)
conference contribution
posted on 09.02.2009, 13:04 by Keming Chen, Changqing LiuChangqing Liu, David Whalley, David HuttDavid Hutt
The stability of Ni3P and its effect on the reaction with molten tin were evaluated in the present study by comparing the reaction behaviour of Ni-P coatings in the as-plated and heat-treated conditions. It was found that after the solder reaction a dark layer of Ni3P was formed at the interface on Ni-P coatings in both conditions, but its thickness was thinner on heat-treated coatings than on as-plated coatings. From the compositional analysis on the cross-sections, it was found that not all the P ejected from the interfacial reaction between Sn and Ni-P was consumed by the formation of Ni3P, as P was detected in a second layer of interfacial phase which also contained Ni and Sn. The formation of Ni3P was found to be characteristic of a diffusion process, whilst the thickness of Ni-P coating consumed during the reaction was found to be linearly proportional to the reaction time. It is concluded that the Ni3P phase formed during the solder reaction is not stable and therefore cannot act as an effective barrier to reactions with liquid solders.



  • Mechanical, Electrical and Manufacturing Engineering


CHEN, K. ... et al, 2005. Stability of Ni3P and its effect on the interfacial reaction between electroless Ni-P and molten tin. IN: IEEE International Symposium on Electronics Materials and Packaging. EMAP 2005, Tokyo, 11-14th December 2005, pp. 107-111




VoR (Version of Record)

Publication date



This is a conference paper [© IEEE]. It is also available from: http://ieeexplore.ieee.org/xpl/RecentCon.jsp?punumber=10650. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.





Usage metrics