Hello I know that there are not a lot of Fab Guys still out there, but here goes. Over the years I have seen a problem with coverage of the oxide replacement along the traces when the layers have been etch using cupric rather than alkaline. What you see is a lack of coverage on the fine traces with full coverage on the larger lines and ground planes. The coverage problem is worse as the copper weight gets higher. This seems to point to a problem that begins in the cupric etcher, and becomes worse the longer the layer is in the etcher. If the layers are passed thru a chem clean (acid) prior to oxide replacement the problem goes away. Typical clean prior to oxide replacement is alkaline (dryfilm residue). This seems to indicate that whatever is on the edge of the trace is acid soluble. Most people seem to blame the dryfilm strip process, but the isolated lines and ground planes don't have the problem. I would appreciate any input. Thanks. --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 -----------------------------------------------------