Certainly plasma does its job as it has in the PCB industry for over 20 years as a method used to etch back drilled MLB polyimide holes to be plated. Obviously, as well, it is used in the hybrid business to clean ceramic substrates before some metallizations and assembly. The residue, in those and other processes, is deposited as "ash" on the chamber walls. Strangely, some process folks don't remove it as it seems a good process indicator not to be messed with. In any case, it "cleans" the hell out of most stuff on this or other planets. MoonMan --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d 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 delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------