The manufacturers of plasma etchers have the information you seek. Call them up for applications information. I have a little pamphlet from March Instruments that is quite useful for my needs, but these companies should be able to tell you anything you need to know. best regards mark Mark W. Lund, PhD Director >> Soft X-ray Web page http://www.moxtek.com<< MOXTEK, Inc. 452 West 1260 North Orem UT 84057 801-225-0930 FAX 801-221-1121 lundm@xray.byu.edu "The state is good at simple tasks, like killing people and seizing their wealth. It has far more trouble reaching inside individuals and making them good." Doug Bandow