Hi everyone, I am etching a 4-inch silicon wafer in the RIE using O2, and CF4, in combination. Using positive photoresist, my goal is to create an array of silicon pillars covering the surface of the wafer. I am trying to push the limits of the machine, and trying to etch several microns. I etched for 5 minutes and was able to get 1.5 micron tall pillars, the wafer came out of the machine very dirty, with a film-like residue on it, and looking very scratched up. I think I might have an idea of what this is, but I would appreciate anyone else's input, or a way to prevent it. *Sebastian Freeman* *Ph.D Student* *Binghamton University * *Thomas J. Watson School of Engineering* *Department of Bioengineering* *Office: Biotechnology Building 2629* *E-mail: sfreema1@binghamton.edu* _______________________________________________ Hosted by the MEMS and Nanotechnology Exchange, the country's leading provider of MEMS and Nanotechnology design and fabrication services. Visit us at http://www.mems-exchange.org Want to advertise to this community? See http://www.memsnet.org To unsubscribe: http://mail.mems-exchange.org/mailman/listinfo/mems-talk