Michael, The available nondestructive techniques are XRF, beta-backscatter, resistance, eddy current, Hall-Effect (magnetic) and Induction Probe. The first three can measure the gold under the photoresist but not the photoresist, the latter 3 can measure the photoresist over gold. At these thicknesses, cross-sections are very difficult. Happy Holden Asian Pacific Materials Michael McMonagle <[log in to unmask]> Sent by: TechNet <[log in to unmask]> 01/31/2006 11:46 AM Please respond to TechNet E-Mail Forum <[log in to unmask]>; Please respond to Michael McMonagle <[log in to unmask]> To [log in to unmask] cc Subject [TN] Au & Photoresist Thickness Measurement I have been thrown an interesting question that I cannot answer, so I'll toss it out here for y'all to ponder. We are looking for a way to measure the thickness of gold and photoresist on a ceramic substrate. The test needs to be non-destructive for use as an in-process production test, measuring gold in the range of 5 microns covered with photoresist in the range of 3-6 microns. Any inputs greatly appreciated, thanks.. Mike McMonagle Quality Manager OYO Geospace 7007 Pinemont Drive Houston, TX 77040 Ph 713-986-8650 Fx 713-986-8725 --------------------------------------------------- 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 -----------------------------------------------------