Dave,

I had a similar problem a few years back on an automotive application and
did an extensive failure analysis and resulting DOE. Contamination and/or
epoxy bleed were suspected but were not evident in SEM, Auger or ESCA. It
will take me a couple days to dig through my archives for the results and
refresh my memory, which I will do.

In either regard, I implemented an evaluation at incoming inspection which
completely eliminated bad lots from getting into production and also
highlighted a superior vendor.  Contact me off line.

Bruce Misner

> ----------
> From:         Dave Gardiner[SMTP:[log in to unmask]]
> Reply To:     TechNet E-Mail Forum.;Dave Gardiner
> Sent:         Tuesday, September 26, 2000 9:47 PM
> To:   [log in to unmask]
> Subject:      [TN] ENIG SMD PWBs Aluminum wire bonding
>
> Thanks all for your suggestions on epoxy bleed. Plasma clean and vacuum
> bake are being investigated. Has anyone seen any specifications that
> cover epoxy bleed or bondability. We have one part number where we have
> twice had trouble with no stick to 15 grams pull on the same panels. We
> had tests done for surface contamination but there was little difference
> in the findings between good and bad boards.
>
> Dave Gardiner
>
> ##############################################################
> TechNet Mail List provided as a free service by IPC using LISTSERV 1.8d
> ##############################################################
> To subscribe/unsubscribe, send a message to [log in to unmask] with
> following text in
> the body:
> To subscribe:   SUBSCRIBE TECHNET <your full name>
> To unsubscribe:   SIGNOFF TECHNET
> ##############################################################
> Please visit IPC web site (http://www.ipc.org/html/forum.htm) for
> additional
> information.
> If you need assistance - 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 subscribe/unsubscribe, send a message to [log in to unmask] with following text in
the body:
To subscribe:   SUBSCRIBE TECHNET <your full name>
To unsubscribe:   SIGNOFF TECHNET
##############################################################
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information.
If you need assistance - contact Keach Sasamori at [log in to unmask] or
847-509-9700 ext.5315
##############################################################