We use a moving shutter containing slits in close contact with a substrate to control the interaction time of gas discharges with the substrate for nanoscale layer/nanostructure processing. Both shutter and substrate are located on the rf-powered electrode and can be biased relative to the plasma. Once the plasma proper-ties and electrode bias voltage are fully established, the shutter with slits begins to move at a controlled speed across the substrate to expose the substrate for the desired interaction time to the plasma. We show that for a fluorocarbon-based plasma etching process, steady-state etching conditions can be achieved within less than 2 s. This approach enables precise removal or deposition of nanoscale layers employing gas discharges. (c) 2006 American Vacuum Society.