Multi-antenna RF Ion Source at a High RF Power Level

Journal Article · Thu Mar 12 00:00:00 EDT 2009 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3112523· OSTI ID:21269109

Oka, Y; Kaneko, O; Takeiri, Y; Tsumori, K; Osakabe, M; Ikeda, K; Nagaoka, K; Asano, E; Sato, M; Kondo, T; Shibuya, M; Komada, S ^[1]; Shoji, T ^[2]

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1. National Institute for Fusion Science/-NINS-, Oroshi, Toki 509-5292, Gifu (Japan)
2. Nagoya university, Chikusa, Nagoya 464-8603 (Japan)

A multi-antenna radio-frequency ion source with a Faraday shield is newly tested at a high RF power level in a large area negative ion source of 1/5th scale of the Large Helical Device-NNBI ion source. Inductively coupled dense hydrogen plasmas were generated uniformly over an area of 25x25 cm{sup 2} at an RF input power up to 300 kW for a 10 ms pulse duration. A large negative plasma potential for the non-Faraday shielded antenna was remarkably reduced by introducing a Faraday shield. The positive ion saturation current density measured by Langmuir probe reached 148 mA/cm{sup 2} at 174 kW around the center of the plasma. The optimal hydrogen filling pressure ranged around 0.13 Pa- 0.4 Pa for the positive ions. Ion beam extraction with a single hole ({phi} 0.5 cm) extractor has been studied systematically. A maximum H{sup -} ion beam current density of 1.6 mA/cm{sup 2} was obtained preliminarily. It was confirmed that the plasma profile was controllable by both the number and configuration of the antennas.

• OSTI ID: 21269109
• Journal Information: AIP Conference Proceedings, Vol. 1097, Issue 1; Conference: 1. international symposium on negative ions, beams and sources, Aix-en-Provence (France), 9-12 Sep 2008; Other Information: DOI: 10.1063/1.3112523; (c) 2009 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ANTENNAS
CATIONS
CURRENT DENSITY
HYDROGEN
HYDROGEN IONS 1 MINUS
ION BEAMS
ION SOURCES
LANGMUIR PROBE
LHD DEVICE
PLASMA
PLASMA BEAM INJECTION
PLASMA HEATING
PLASMA POTENTIAL
PLASMA PRODUCTION
PLASMA RADIAL PROFILES
PRESSURE RANGE MILLI PA
PULSES
RADIOWAVE RADIATION