Victor, You usually only find high-temp solderballs on ceramic devices. The reason for the high-temp solderballs is to increase the column height to improve solder joint reliability. This is due to the CTE mis-match between the Ceramic and FR-4. Russell Nowland Lucent Technologies, Suite 100 7725 West Reno Ave. Oklahoma City, OK 73127 Phone: 405-782-7765 Fax: 405-782-7905 email: [log in to unmask] -----Original Message----- From: Victor Hernandez [mailto:[log in to unmask]] Sent: Thursday, March 06, 2003 2:40 PM To: [log in to unmask] Subject: [TN] Solder ball composition Fellow TechNetters, What is the reasoning behind using High Temp Solder ( 95/5 ) for BGA's versus conventional 63/37 Eutectic solder besides different melting points? Is the strength factor an issue. I would like to hear from the metallurgical group on this issue. Victor, --------------------------------------------------- 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 ----------------------------------------------------- --------------------------------------------------- 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 -----------------------------------------------------