skip to main content

Title: Comparative measurements of plasma potential with ball-pen and Langmuir probe in low-temperature magnetized plasma

The ball-pen probe (BPP) is used for direct plasma potential measurements in magnetized plasma. The probe can adjust the ratio of the electron and ion saturation currents I{sub sat}{sup −}/I{sub sat}{sup +} to be close to one and therefore its I-V characteristic becomes nearly symmetric. If this is achieved, the floating potential of the BPP is close to the plasma potential. Because of its rather simple construction, it offers an attractive probe for measurements in magnetized plasma. Comparative measurements of plasma potential by BPPs of different dimensions as well as one Langmuir probe (LP) in an argon discharge plasma of a cylindrical magnetron were performed at various experimental conditions. An additional comparison by an emissive probe was also performed. All these types of probes provide similar values of plasma potential in a wide range of plasma parameters. Our results for three different BPP dimensions indicate that the BPP can be operated in a cylindrical magnetron DC argon discharge if the value of the ratio of the magnetic field and neutral gas pressure, B/p, is greater than approximately 10 mT/Pa.
Authors:
; ;  [1] ;  [2] ;  [1] ;  [3]
  1. Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 3, 12116 Prague 2 (Czech Republic)
  2. Institute of Plasma Physics AS CR, v.v.i., Za Slovankou 3, 18200 Prague 8 (Czech Republic)
  3. (Czech Republic)
Publication Date:
OSTI Identifier:
22408264
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 3; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ARGON; CURRENTS; CYLINDRICAL CONFIGURATION; ELECTRIC CONDUCTIVITY; ELECTRIC DISCHARGES; ELECTRONS; IONS; LANGMUIR PROBE; MAGNETIC FIELDS; MAGNETRONS; PLASMA; PLASMA POTENTIAL; SYMMETRY; TEMPERATURE RANGE 0065-0273 K