Hi Inge - what is the pwb finish? Dave Hillman Rockwell Collins [log in to unmask] Inge <[log in to unmask]> Sent by: TechNet <[log in to unmask]> 09/03/2009 02:15 PM Please respond to TechNet E-Mail Forum <[log in to unmask]>; Please respond to Inge <[log in to unmask]> To [log in to unmask] cc Subject [TN] BGA Pb-free, this is what I feared: Tin whiskers We have HASL and via-in-pad. Electrical issues, disturbed signals. There were hundreds of Tin whiskers on inside of the unfilled vias, and even whiskers from solder pads circumperiphery, pointing at the nearby solder pads. I suspect that the signal failures are caused by CAFs. Have any of you seen a connection between the presence of Tin whiskers and CAF growth? All BGA via-in-pads are solder mask defined. If you want photos, I can send a couple to the PA immigrant. /Inge --------------------------------------------------- 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 -----------------------------------------------------