In a message dated 7/28/2005 11:44:13 A.M. Eastern Daylight Time, Jeffrey.Bu [log in to unmask] writes: Does anybody out there have Board surface recommendations for a RoHs process ? ____________________________________ I'd recommend Pb-free HASL: * far-better planarity than it's lead-based counterpart, appropriate through 20-mil pitch. * no embrittlement possibilities like ENIG, * solder to copper instead of nickel as with ENIG (and all that implies) * cheaper than ENIG * excellent shelf life * can be reworked * doesn't introduce 3rd/4th metals to your solder joint as with ENIG * isn't banned by the Aerospace industry like immersion silver * can be retrofitted in pre-existing HASL equipment at a fraction of the cost to installing silver / tin / ENIG / OSP lines. * has reduced handling sensitivities versus OSP, TIN or SILVER * is appropriate as a final finish, whereas no SILVER or OSP manufacturer warrants immersion processes as a final post-assembly finish. * ...and despite Urban Legends, lead-free HASL solder is available in operating temperatures suitable for 140-deg. FR-4. Many veteran process engineers still find nothing solders like solder, and there's good reasons for their position. But I'm hoping you want more than anecdotes so write-back if you'd care to pursue Pb-free HASL further. Cheers! ROBERT LAZARA VP, Marketing & Tech Support Tel: (800) 560-9457 Fax: +01 603.880.7975 =Circuit Connect= UL Listed - ISO Registered - SMTA Member - IPC Member - EPA Partner - RoHS Compliance --------------------------------------------------- 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 -----------------------------------------------------