Yes it was! This whole exchange caused me to do a little (very little) Googling for a quick refresh. So far as I found, in electronics a NiP layer is used in some otherwise pure Ni electrolytic plating intended for wire bonding, this to reduce Kirkendall voiding on wire bonds, but not soldering. Regards Mike -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Per-Erik Tegehall Sent: Wednesday, May 30, 2012 8:32 AM To: [log in to unmask] Subject: Re: [TN] Phosphorus at the BGA pad That was very interesting information. You write that it is used for a number of other electronic applications. Do you know if it ever has been used as finish on surfaces to be soldered? Per-Erik -----Ursprungligt meddelande----- Från: TechNet [mailto:[log in to unmask]] För Martin Bayes Skickat: den 30 maj 2012 08:55 Till: [log in to unmask] Ämne: Re: [TN] Phosphorus at the BGA pad As others have already posted, conventional electrolytic nickel gold used as a PWB final finish, uses a pure nickel underlayer. It is worth noting that, for a number of other electronic component applications, electrolytic nickel-phosphorus is used commercially, rather than pure electrolytic nickel, due to its higher corrosion resistance. Such electrolytic nickel-phosphorus baths, typically operated at low bath pH (below 2) and contain hypophosphorous acid. Co-deposition occurs in an analogous manner to electroless systems (with P-content controlled by variables including bath pH, hypophosphous acid content and current density). The development of modern day electroless nickel systems was triggered by the serendipitous discovery of electrolytic nickel phosphorus systems by Brenner and Riddell at what was then the National Bureau of Standards (now NIST) in the 1940's ( A. Brenner and G. Riddell, J. Res. N. B. S., (37), 32 (1946). Martin ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please visit http://www.symanteccloud.com ______________________________________________________________________ *** Attention *** This electronic mail including attachments is intended only for the person(s) or entity to which it is addressed and may contain confidential and/or legally privileged material and information. Unauthorized disclosure, copying, distribution or use of this material and information may be unlawful and is prohibited. If you are not the intended recipient and have received this mail in error, please contact the sender and delete all contents of the e-mail as well as any copies made. Thank you! *** Attention *** This electronic mail including attachments is intended only for the person(s) or entity to which it is addressed and may contain confidential and/or legally privileged material and information. Unauthorized disclosure, copying, distribution or use of this material and information may be unlawful and is prohibited. If you are not the intended recipient and have received this mail in error, please contact the sender and delete all contents of the e-mail as well as any copies made. Thank you! ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________