John: Do you know if the 5DX machine can pick up something like this? I am looking for other non-destructive test method to validate the finding. Also how and what I should check for the BGA substrate finish? According to the process engineer oversea, the components they used ( they still have un-used parts in stock) appear be in normal condition. With the solder ball already mounted to the BGA substrate, how should the inspection be carried out? Sorry to keep asking question, but I am not familiar with the IC fabrication process. The part is ROHS btw. Thanks Rudolph -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of John Burke Sent: Friday, September 15, 2006 11:43 AM To: [log in to unmask] Subject: Re: [TN] Need help on a Dye & Pry test result AAAAAAAAAAAAAAAAAArggggggggggghhhhhhhhhhhhhhhh It depends............ BUT from what you describe I would check the finish on the BGA substrate, I have seen this a few times on enig BGA substrates caused by stress in cooling down from reflow temperatures. The reason for the corners is maximum stress due to longest length on diagonal. John -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Rudolph yu Sent: Friday, September 15, 2006 11:22 AM To: [log in to unmask] Subject: [TN] Need help on a Dye & Pry test result Recently I asked an outside lab to perform the dye & pry test on couple failure assemblies. The heatsink was not removed from the PBGA prior to the dye application. According to the result and pictures, the corner pads of the BGA package from both units were covered by the dye completely . An indication that a seperation was formed between the BGA package's pads and its original solder balls at that one corner after the SMT process. Have anyone of you experienced this kind of defects in the past and what could be the root cause of this phenomena? ( Poor plating from the IC manufacturer? SMT reflow profile? PCB warpage? ) I have been in the industry for 10 years and have never seen thing like this. Is it common?? Thanks Ryu --------------------------------------------------- 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 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- 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 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- 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 847-615-7100 ext.2815 -----------------------------------------------------