Specification is 2 microinches minimum at -4sigma from the process mean, typical values 3-5 microinches for Au, 120 to 240 microinches for Ni. Regards Gerard O'Brien. Co-chair 4-14 plating committe -----Original Message----- From: Jones, Evamaria [mailto:[log in to unmask]] Sent: Wednesday, March 08, 2006 10:56 AM To: [log in to unmask] Subject: [TN] Minimum thickness required for gold immersion finish on PTH and Vias Question, Does anyone out there know the minimum thickness required for a gold immersion finish for PTH's and Vias. A colleague ask me and I don't have a copy of the IPC-4552. There was an article in Printed Circuit Design and Manufacture in February 2006 titled Know Your Surface Finish. It recommended 2-4 uin". I admit...I am an assembly gal not a PWB fab gal. What does the spec say? The article was not very favorable toward Imm. AG. Any warnings or risks? Evamaria Quality Engineer Instructor ________________________________ --------------------------------------------------- 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 ----------------------------------------------------- --------------------------------------------------- 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 -----------------------------------------------------