Bev, What type of Pd? Plated, evaporated, Pd/Ag? The dissolution rate is Pd process dependent (not all Pd are made equal). jk >-----Original Message----- >From: TechNet [mailto:[log in to unmask]] On Behalf Of >Dave Hillman >Sent: Thursday, July 31, 2003 3:51 PM >To: [log in to unmask] >Subject: Re: [TN] Thick Palladium on Leads > > >Hi Bev! You need to be careful with the Pd thickness. When >soldering to thick Pd plating layers you can potentially have >problems with "Pd embrittlement" of the solder joint. Pd and >Sn for an intermetallic phase >(PdSn4) which behaves in the same fashion as the AuSn4 >intermetallic phase for gold embrittlement of solder joints. >There are two industry reference I know of off the top of my >head - the NCMS Surface Finishes Study and a Collins paper >published at the 1996 SMI conference. If you keep the Pd >thickness between 9-15 microinches you should be able avoid >the PdSn4 phase with a controlled soldering processes. Also >note that Pd has a very slow diffusion rate so you may have to >adjust your soldering process times. Good Luck. > >Dave Hillman >Rockwell Collins >[log in to unmask] > > > > Bev Christian > <[log in to unmask] To: >[log in to unmask] > ET> cc: > Sent by: TechNet Subject: [TN] >Thick Palladium on Leads > <TechNet@listserv > .ipc.org> > > > 07/31/2003 12:28 > PM > Please respond to > "TechNet E-Mail > Forum."; Please > respond to Bev > Christian > > > > > > >Technetters, >I have searched the archives and all I have been able to find >is one informative e-mail from Phil Hinton from August 22, >1998. Has anyone every run across palladium as a thick >undercoat? if so, what, if any, grief did it cost you? > >regards, >Bev Christian >Research in Motion > >--------------------------------------------------- >Technet Mail List provided as a free service by IPC using >LISTSERV 1.8e 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 or >(re-start) delivery of Technet send e-mail to >[log in to unmask]: SET Technet NOMAIL or (MAIL) >To receive ONE mailing per day of all the posts: send e-mail to >[log in to unmask]: SET Technet Digest >Search the archives of previous posts at: >http://listserv.ipc.org/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 1.8e 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 or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/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 1.8e 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 or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/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 -----------------------------------------------------