On Tue, 17 Sep 2002 17:23:00 -0700, Peter Lee <[log in to unmask]> wrote: >Technet, > >If I may continue my question on BGA rework process: > >Recently we have seen intermitted failures from a few BGA assemblies. >After removing the suspicious BGA on the rework station we noticed >dewetting on a majority number of pads of the removed BGA. The solder >ball residues were mostly attaching to the board. > >Has anyone seen this before? How likely can this be caused by a >non-optimum rework removal profile Is baking of the board normal prior >to rework (removal/re-placement)? > >We are tackling this issue from the part supplier side and looking at >performing destructive X-ray analysis. Can someone give me an idea of >what the ball attachment process is on the BGA? > >Rgds, >Peter > >--------------------------------------------------------------------------- ------ >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 >--------------------------------------------------------------------------- ------ I saw your post on the list and it resembles some problems we've had here with BGA's. I have a question, do the dewetted pads on the components look dark? ("Black pads") Rgds Tore --------------------------------------------------------------------------------- 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 ---------------------------------------------------------------------------------