One more q . Are you using no clean to for balling process? -------------------------- Sent using BlackBerry ----- Original Message ----- From: TechNet <[log in to unmask]> To: [log in to unmask] <[log in to unmask]> Sent: Mon Nov 10 12:39:39 2008 Subject: Re: [TN] Effect of Soldering in a Ni atmosphere on BGA reliabilty Hi Eric, Of course anything that you can eliminate from the FA should be considered. HOWEVER - since the failure is at the ball to substrate interface (I presume you manufacture BGA's?) you would do far better to consider a side by side comparison of the parameters of the shock tests (yours and theirs), and also analysis of any unassembled BGA devices to analyze the metallurgy at the ball to BGA substrate interface before the assembly sequence as well as the same analysis on the failed units. For the record you will also need an accurate assessment of the conditions at the solder joints during the assembly reflow sequence as well as the details of the solder used for the actual assembly. John Burke (408) 515 4992 -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Eric CHRISTISON Sent: Monday, November 10, 2008 1:47 AM To: [log in to unmask] Subject: [TN] Effect of Soldering in a Ni atmosphere on BGA reliabilty A customer has experienced solder joint failures in a lead free BGA device which are unexpected for us. The test the solder joints failed was a shock test in the plane of the PWB and the joints failed at the interface between the SJ and our BGA device substrate. We've done similar tests without failure but when we did our trials we soldered the devices onto the boards in a hot air oven. Our customer used a nitrogen oven. Could this affect SJ strength in any way? Just wondering whether this is worth investigating. Regards, -- Eric Christison Msc Mechanical Engineer Consumer & Micro group Imaging Division STMicroelectronics (R&D) Ltd 33 Pinkhill Edinburgh EH12 7BF United Kingdom Tel: +44 (0)131 336 6165 Fax: + 44 (0)131 336 6001 --------------------------------------------------- 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 ----------------------------------------------------- --------------------------------------------------------------------- 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 -----------------------------------------------------