Additionally, consider "Electroless Nickel Immersion Gold And Black Pad", R Sakelson and S Gold, Circuitree [http://www.circuitree.com], 1/01, V14, N1, P10 Dave Fish ----- Original Message ----- From: Ingemar Hernefjord (EMW) <[log in to unmask]> To: <[log in to unmask]> Sent: Monday, January 22, 2001 7:42 AM Subject: Re: [TN] Increased Phosphorus in Electroless Ni > It's late to say thank you, Georg Milad, > but better late than never as they say on Greenland. > > Someone from Shipley have been here together with the PWB maker concerning a > superlarge BGA soldering problem. We have learnt a lot since september but > there remains issues still. What you said below is typical for most articles > and specs: layer thickness and phosphorous but little about foreign stuff > that can appear (even for the best in the game it seems), such as fenoxy, > epoxies, glycols, hydrates, carboxyls and a lot more. We made a TOFSIMS on > some board lands and found SiCH3, C2H3, C3H7, Fe, C5H9, In, SnOH, just to > mention an example. And added to that comes the morphologic aspects and > about microhardness and boundaries and size and shape of Nickel domes. > > I thought I had learnt a lot about the BGA soldering, but suddenly I feel > how empirical a lot seems to be. "We use to..." or "We think that..". > Understand that too, but would like something more in the spec than just > thickness and P%. > > If there is something I can hang up on the wall, and tell people 'this is > how a solder pad is being done' I would be vary glad. Guess all other > Ericsson groups agree (in silence, of course) > Best regards > > Ingemar Hernefjord > Ericsson Microwave Systems > > PS. Isn't Steph Meschter within Lockheed Martin any more or did he sign off? > > > > > > > -----Original Message----- > From: [log in to unmask] [mailto:[log in to unmask]] > Sent: den 6 september 2000 21:04 > To: [log in to unmask]; [log in to unmask] > Cc: [log in to unmask] > Subject: Re: [TN] Increased Phosphorus in Electroless Ni > > > Here is my two cents worth on the topic of Electroless Ni , Phosphorous > content. > Here at Shipley our recommendation for thickness of Electroless Ni is 100 to > > 250 uins or 2.5 to 6.0 microns. For the gold thickness we recommend 2 - 4 > uins (0.05 - 0.10 microns) as the best thickness to protect the Ni during > storage and not to create any Ni defects during processing. > As far as Phosphorous content in the Ni deposit we are presently staying > with > 7 -9% P. We have seen data, where High phos (10 - 12%) and Low phos (5 -7%) > > gave equally good results, with regards to incidences of "Black Pad". > Our tests indicate that High Phos is prone to skip plating and gold adhesion > > failure. > The IPC Plating Subcommittee 4-14 will be meeting in Miami, during IPC Works > > 2000, at 1:30 to 3:00pm on September the 11th, 2000. The agenda of the > meeting is to define an IPC-Standard for Electroless Nickel and Immersion > Gold as well as Electroless Gold, as surface finishes widely used in the > industry today. Anyone interested in participating is welcome to join the > meeting or send his input to me, and I will keep him or her informed of the > committee progress. > George Milad > Tech Marketing Mgr. > Shipley Ronal Inc > Chairman IPC Subcommittee 4 -14 > > -------------------------------------------------------------------------- ------- > Technet Mail List provided as a free service by IPC using LISTSERV 1.8d > To unsubscribe, send a message to [log in to unmask] with following text in > the BODY (NOT the subject field): SIGNOFF Technet > To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL > Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives > Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional > information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 > -------------------------------------------------------------------------- ------- > --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------