James, I have used silver epoxies for 20 years and support all the concerns all ready raised. I have found that curing at a lower temp does improve the life of a Ag epoxy/solder interface but it is still poor... as others mentioned, increased DC resistance over time. As Jim mentioned, I would give it maybe 6 mo in a benign lab evironment at best and immediate at worst. Ag epoxy to ENIG is certainly fine for table top, room temp lab environment and is even reliable especially with Ni/Au plate and is probably why Bill is having success with Ag epoxy (solder is on the other side and I know he's not wire bonding to a tin or solder coat). If you don't have humidity control, Ag migration should be a concern and conformal coat recommended. Board flexure opening interfaces is definitely a problem. Bottom line: I avoid solder-Ag epoxy interfaces, period. Good Luck, Bruce > ---------- > From: Marsico, James[SMTP:[log in to unmask]] > Reply To: TechNet E-Mail Forum.;Marsico, James > Sent: Tuesday, January 23, 2001 3:34 PM > To: [log in to unmask] > Subject: [TN] silver epoxy & solder coated parts > > Hello, Technet... > > Here is an unusual situation. We have to assemble a surface mount > assembly > using silver epoxy. Some of the components will be solder coated. I > know, > don't bother asking... this is the way it has to be. The good thing is > that > this assembly is a prototype for bench-top laboratory use only. There is > no > harsh environment and needs to operate 1, maybe 2, years. The question is > does anyone foresee any problems? What happens when one mixes toe two > technologies? > > Thanks, > Jim Marsico > EDO Electronic Systems Group > [log in to unmask] <mailto:[log in to unmask]> > > -------------------------------------------------------------------------- > ------- > 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 ---------------------------------------------------------------------------------