You may want to try a diamond or square pad instead of a star. I would think that the inner angles on the star would be stress concentration points.
 
Dave
-----Original Message-----
From: Mark Roslawski [mailto:[log in to unmask]]
Sent: Wednesday, October 16, 2002 9:45 AM
To: [log in to unmask]
Subject: [TN] Z-axis BGA solder joint verification ?

Dear TechNetters:
 
I have a customer that wants to know if there is any way of verifying the Z axis solder joint on BGAs ?
 
He has a x-ray machine that he can see in x and y axis', but he can not see in z-axis for good solder joint verification.
 
He thought about using a star type design pad landing as opposed to a circle pad landing so he could see the solder flow into the points of the star.  Has anybody done anything like this or does anybody have any recommendations ????
 
Any and all input is appreciated.
 
Thank You
 
 
Mark Roslawski
VP Marketing
 
ThermalWorks
2910 South Oak Street
Santa Ana, CA. 92707
 
Tel.  (714) 540-8454 x166
Fax. (714) 540-1299
 
Email: [log in to unmask]
 
Web Sites: www.thermalworks.com
                   www.SDCcircuits.com
--------------------------------------------------------------------------------- Technet Mail List provided as a free 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/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------
--------------------------------------------------------------------------------- Technet Mail List provided as a free 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/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------