Characteristics of a large-volume rf-grid discharge plasma

Abstract

The properties of a large‐volume rf (75 MHz) ‐grid discharge plasma have been determined. Measurements in the steady state and in the afterglow indicate that the rf grid produces a plasma with two electron components—a secondary Maxwellian component of density 2×10¹⁰ electrons/cm³ and temperature 4.5 eV and a ’’primary’’ component of density 1×10¹⁰ electrons/cm³ and temperature approximately 15 eV. The ion temperature is ?0.3 eV. A useful 35‐liter argon plasma with a noise level on the order of 1% is easily produced in neutral pressure backgrounds as low as 4×10⁻⁵ Torr.