In this special case, the cross section showed that the joint between the
lead and the solder pad was IMC free, the frost like goldtin platelets were
on the upper side of the lead, superficial so as to say.
Inge
----- Original Message -----
From: "Joyce Koo" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, April 14, 2009 11:18 PM
Subject: Re: [TN] Gold/Tin Intermetallics, why are we afraid?
Agree. If you are the design authority and known the limits of the
application environment. The only danger is someone in thye future will
copy it without such a knowledge. Open a coomon law is the danger.
--------------------------
Sent using BlackBerry
----- Original Message -----
From: TechNet <[log in to unmask]>
To: [log in to unmask] <[log in to unmask]>
Sent: Tue Apr 14 16:55:52 2009
Subject: [TN] Gold/Tin Intermetallics, why are we afraid?
These infamous IMCs are like parias or ghosts in most people's mind in our
business. I shocked our production guys recently by giving the advice to let
the boards go on. Large crystals and bad looking. But I always try to avoid
exaggerations. If no serious temp changes are predicted, nor any severe
power switching, why rework and risk introducing failures? The actual
components were very hard to rework, the cost had been unacceptable. I can
see many of you get the coffee wrong. I don't mean to spread quality
distractions, I talk about very few boards and a unique situation. My
statement was based on the fact that a gold tin intermetallic bond is
extremly strong and can last long, if not exposed to what I pointed at
earlier. I expect to be hammered down in the shop floor until only the nose
is visible....
Inge
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
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
-----------------------------------------------------
---------------------------------------------------------------------
This transmission (including any attachments) may contain confidential
information, privileged material (including material protected by the
solicitor-client or other applicable privileges), or constitute non-public
information. Any use of this information by anyone other than the intended
recipient is prohibited. If you have received this transmission in error,
please immediately reply to the sender and delete this information from your
system. Use, dissemination, distribution, or reproduction of this
transmission by unintended recipients is not authorized and may be unlawful.
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
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 15.0
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
-----------------------------------------------------
|
