The problem is most likely due to thin plating in the via holes which passes
electrical testing before they are assembled and than see a heat excursion.
Once the heat is applied and the boards expands then the thin copper plating
in the middle of the hole would separates and causes opens. Cross section
the vias and make sure that the smallest hole is in the test coupon. If this
is a blind via than the same would occur more dramatically.
----- Original Message -----
From: "Rob Goodwin" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, November 13, 2003 6:10 PM
Subject: [TN] Via Reliability issues


> We have been experiencing some vias not getting plated completely on
several
> boards out of each lot.  The bare boards that come from fab pass the
> connectivity and short test, but the vias don't make it through assembly.
> Has anyone experienced this?  Do you have any experience with a test
coupon
> that we could zero in on suspect boards?
>
> Thanks,
> Rob Goodwin
> Eclipse Electronic Systems, Inc.
>
> ---------------------------------------------------
> Technet Mail List provided as a 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/contentpage.asp?Pageid=4.3.16
for additional information, or contact Keach Sasamori at [log in to unmask] or
847-509-9700 ext.5315
> -----------------------------------------------------
>

---------------------------------------------------
Technet Mail List provided as a 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/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315
-----------------------------------------------------