RF atmospheric pressure micro-plasma in a 35 cm long hollow slot electrode

Summary form only given, as follows. A hollow slot of 35 cm in length has been radio-frequency powered to generate a discharge plasma at atmospheric pressure. We have had prior experience in employing slotted hollow cathodes for laser generation, but the operating pressures never exceeded 133 kPa and the operating frequency 360Hz. This newly developed micro-plasma device consists of a rf driven hollow electrode and a solid transverse electrode which is electrically grounded and placed parallel to the cathode slot. This configuration has achieved at 13.56 MHz a power deposition of 20 W/cm with about 150 V of rf voltage between the grounded electrode and the rf driven hollow slot electrode with an rf current density up to several A/cm/sup 2/. We stabilized the chscharge at high pressure at varying rf frequencies (13.56 MHz, 4 MHz, etc) in both the hollow cathode and hollow anode modes.