Hi, we use a 3 step clean recipe for the RIE: 1: Pressure 100, RIE 200W + ICP 200W: 45sccm O2 + 5sccm SF6 @ 10min 2: Pressure 100, RIE 200W + ICP 200W: 5sccm O2 + 45sccm SF6 @ 10min 3: Pressure 100, RIE 200W + ICP 200W: 45sccm O2 @ 10min kind regards Salam R. Gabran, MASc. Research associate, PhD. Candidate Center for Integrated RF Engineering (CIRFE) Group ECE Dept., University of Waterloo, 200 University Avenue West Waterloo, Ontario, N2L3G1 cell.: 519-729-8066 Web: www.ece.uwaterloo.ca/~sgabran