TECHNET Archives

January 2008

TechNet@IPC.ORG

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
"Whittaker, Dewey (EHCOE)" <[log in to unmask]>
Reply To:
TechNet E-Mail Forum <[log in to unmask]>, Whittaker, Dewey (EHCOE)
Date:
Tue, 29 Jan 2008 14:06:32 -0700
Content-Type:
text/plain
Parts/Attachments:
text/plain (88 lines)
IMHO calling champagne voids Kirkendahl voids is a misnomer; otherwise
what you said would be right. As I have said before, the failure
mechanism in champagne voids is due to Brut force.
Dewey 

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Stadem, Richard D.
Sent: Tuesday, January 29, 2008 12:31 PM
To: [log in to unmask]
Subject: Re: [TN] Microvoids immersion silver

Werner and Don.
I was always under the impression that Kirkendahl voiding was a result
of the noble metal's (in this case, silver) nucleation through the SJ. I
always thought that this was a time-variable migration. I understand how
all of the process variables described in Werner's  response will affect
or support the eventual void formation, but I would not expect Gaby to
find anything in microsections taken immediately after soldering. Would
it not make more sense to thermally cycle the SJs in order to facilitate
the nucleation prior to microsectioning?

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Werner Engelmaier /*
Sent: Tuesday, January 29, 2008 12:35 PM
To: [log in to unmask]
Subject: Re: [TN] Microvoids immersion silver

Hi Gaby,
I take it what you are seeing are 'champagne voids.'
Voids like these are 'encouraged by rough topography copper, excessive
Ag thickness, some solder paste choices and rapid cool-down after
reflow. But as Donald Cullen says in his comprehensive paper, it
"requires the "Perfect Storm" 
of a rather contrived combination of parameters" to produce planar
micro-voiding.
Well Gaby, now you know it-you are "Perfect." ;-)



Werner



**************
Start the year off right.  Easy ways to stay in shape.
     
http://body.aol.com/fitness/winter-exercise?NCID=aolcmp00300000002489

---------------------------------------------------
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
-----------------------------------------------------

---------------------------------------------------
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
-----------------------------------------------------

ATOM RSS1 RSS2