Hello, can anybody help me please? We are getting low level (up to 5 microns high) copper spots left on inner layer panels after the cupric chloride etch. It happens on most kinds of laminate. We have put panels through our chemical clean line and the etch only and the effect is still there. Leaving out the chemical clean line or pumicing the panels first still leaves the spots. The surface is shiny copper and sometimes there appears to be some residue which we believe to be organic from a slight carbon peak on an EDAX scan. We found some sticky residue on the rollers in the etcher which we removed, but the problem didn't go away. We run at 4N HCl and 520mV, regenerating with hydrogen peroxide. Has anyone experienced this before? Did you discover where the organic residue came from and the best way to remove it? --------------------------------------------------- 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 847-509-9700 ext.5315 -----------------------------------------------------