Unleaded ALPHA 0M325, PCB is gold finish. Thanks -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Cheryl L. Johnson Sent: 12 September 2007 19:24 To: [log in to unmask] Subject: Re: [TN] Thermal issue's with unleaded solder paste. What specific lead-free solder and pcb finish are you using? -- Cheryl Johnson (303) 485-8829 home (303) 809-5815 cell -------------- Original message ---------------------- From: "Thomas, Ian (Ian) %" <[log in to unmask]> > Hi, Need some useful advice regarding a current design. > I have a 12 layer FR4-370HR PCB, using stacked uvia's in pad which > connect to planes on layers 2 & 3 which are flooded with no thermal > relief. > > We have seen no issue's with leaded assembly, but on transferring over > to un-lead, we are seeing solder issue's with the BGA's (0.5mm pitch) > on assembly and also rework issuse's with 90% of the other components > (including > 0402's) in getting them off the board. > > Our first thoughts are to thermally relieve all the micro via's, but > there are issue's because this may leave you with only one spoke on a > pin in some areas. > > Has any seen these issue's before? > > Thank's in advance. > > Ian > LSI Technology (Mobility) > > > --------------------------------------------------- > 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 ----------------------------------------------------- --------------------------------------------------- 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 -----------------------------------------------------