RF plasma processing for removal of contaminants in a high voltage anode-cathode gap

Summary form only given, as follows. Experiments at Sandia National Lab have shown the importance of removing contaminants from ion diodes to reduce parasitic losses. At Michigan, experiments are underway to study the technique of RF plasma processing as a means of cleaning contaminants from the anode and cathode in the MELBA high voltage diode (-0.8 MV, 10 kA, 1 /spl mu/s). Diagnostics of the 13.56 MHz RF plasma (typically 90% Ar+10% O/sub 2/) include optical spectroscopy with pre-analysis and post-analysis of contaminants (e.g., CO, CO/sub 2/, H/sub 2/O) by means of a residual gas analyzer. Planned experiments will employ optical and laser diagnostics to investigate the effects of cleaning on electron-stimulated desorption of neutral and ion contaminants during high voltage diode pulses.