Hello Jim,

Sounds like dendritic growth.  Have the dendrites analyzed - I have seen
black dendrites which are silver.  Your cap terminations are probably
silver, which is suceptible to electromigration, accelerated by bias,
surface ionics and moisture.  The only way to avoid this is to change the
caps.

-Gregg
[log in to unmask]

At 09:49 AM 11/4/97 +0000, Jim Hedderick wrote:
>Can any one help me with a solution to this problem,
>we have recently experenced board failures because of a contamination
>across various sm  capacitors which first looks like a splat of black paint
>which run diagonally across the cap, under a microscope it looked like
>fern leaves.
>Our boards are wave soldered and w edo not clean after solder flow.
>
>Regards
>Jim Hedderick

##############################################################
TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
##############################################################
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.
For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311
##############################################################