Sender: |
|
X-To: |
|
Date: |
Wed, 3 Sep 2003 07:54:41 EDT |
Reply-To: |
|
Subject: |
|
MIME-Version: |
1.0 |
Content-Transfer-Encoding: |
7bit |
Content-Type: |
text/plain; charset="US-ASCII" |
From: |
|
Parts/Attachments: |
|
|
Hi Lance,
I would venture to say, that the CTE of these diodes is significantly
different than the PCB. I would further hazard the guess, that the diodes with
disturbed SJs are predominantly those oriented in the conveyor belt direction. What
I think is happening is that the leading edge SJ solidifies, the trailing
edge one is still pasty, and the differential contraction on cooling causes the
trailing SJ to be disturbed.
Regards,
Werner Engelmaier
Engelmaier Associates, L.C.
Electronic Packaging, Interconnection and Reliability Consulting
7 Jasmine Run
Ormond Beach, FL 32174 USA
Phone: 386-437-8747, Fax: 386-437-8737, Cell: 386-316-5904
E-mail: [log in to unmask], Website: www.engelmaier.com
---------------------------------------------------
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
-----------------------------------------------------
|
|
|