The copper tin intermetallic layer thickness will depend on reflow temperature and time at temperature. Note: the IMC will grow over time and will not stay fixed. We have data that was presented in the Lead free IPC/JEDEC conference showing the increase in IMC thickness when the joint is subjected to accelerated age testing, ( 150 deg C for up to 1000hours). Best regards George Milad National Accounts Manager for tTchnology Uyemura International Corporation 240 Town Line Rd Southigton, CT06489 860 793 4011 (O) 516 901 3874 (cell) [log in to unmask] --------------------------------------------------- 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 -----------------------------------------------------