Here is a little more on the specifics of the problem that we saw.

The material erupting from the 10mil tented vias is believed to be tin bath
residue. EDX shows a unique Sn spike in the area of the board with the
contamination.
The contamination potential exists for all finishes (Cu with OSP, imm Sn,
imm Ag) with tented vias. The highest risk is for the unrelieved 10mil
drilled via geometry. This geometry and problem was found only under BGA
U19 on this assembly.


Cheryl Tulkoff
Phone:(512) 683-8586
Fax: (512) 683-8847
National Instruments
11500 N. Mopac Expressway
Building A
Austin, TX 78759-3504





             James Hofer
             <[log in to unmask]
             m>                                                         To
             Sent by: TechNet          [log in to unmask]
             <[log in to unmask]>                                          cc

                                                                   Subject
             11/02/2004 02:17          Re: [TN] Contamination on the
             PM                        fabs....


             Please respond to
                James Hofer
             <[log in to unmask]
                    m>






It almost looks like some sort of background plating associated with some
chemistry entrapped in the vias.


James Hofer
Director of Operations
Accurate Circuit Engineering
3019 S. Kilson Dr.
Santa Ana Ca. 92707-4202
714-546-2162 work
714-473-6127 cell
[log in to unmask]
----- Original Message -----
From: "Ken Patel" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, November 02, 2004 12:14 PM
Subject: [TN] Contamination on the fabs....


> Fab & Assembly Experts,
>
> I am seeing some kind of contamination to bare boards. I have put
pictures
> at Steve web site for everyone's review and here is the link.
>
>
>
> http://www.stevezeva.homestead.com <http://www.stevezeva.homestead.com/>
>
>
>
> Does anyone have seen similar kind of contamination? Is it some kind of
> corrosion? It looks outside of board to me but not sure as I have seen
the
> boards personally yet. Boards are processed Electroless Nickel Immersion
> Gold.
>
>
>
> Any help will be highly appreciated.
>
>
>
> Re,
>
> Ken Patel
>
>
>
>
> ---------------------------------------------------
> 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
847-615-7100 ext.2815
> -----------------------------------------------------
>

---------------------------------------------------
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
847-615-7100 ext.2815
-----------------------------------------------------

---------------------------------------------------
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 847-615-7100 ext.2815
-----------------------------------------------------