11-13 GHz electron cyclotron resonance plasma source using cylindrically comb-shaped magnetic-field configuration for broad ion-beam processing

Journal Article · Wed Nov 15 00:00:00 EST 2006 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.2387885· OSTI ID:20861495

Asaji, Toyohisa; Kato, Yushi; Sato, Fuminobu; Iida, Toshiyuki; Saito, Junji ^[1]

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1. Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan and Development Center of Advanced Technology, Tateyama Machine Co., Ltd., 30 Shimonoban, Toyama 930-1305 (Japan)

An electron cyclotron resonance (ECR) plasma source for broad ion-beam processing has been upgraded by a cylindrically comb-shaped magnetic-field configuration and 11-13 GHz frequency microwaves. A pair of comb-shaped magnets surrounds a large-bore discharge chamber. The magnetic field well confines plasmas with suppressing diffusion toward the axial direction of the cylindrical chamber. The magnetic field is constructed with a multipole and two quasiring permanent magnets. The plasma density clearly increases as compared with that in a simple multipole magnetic-field configuration. The frequency of microwaves output from the traveling-wave tube amplifier can be easily changed with an input signal source. The plasma density for 13 GHz is higher than that for 11 GHz. The maximum plasma density has reached approximately 10{sup 18} m{sup -3} at a microwave power of only 350 W and a pressure of 1.0 Pa. The enhancement of plasma generation by second-harmonic resonance and microwave modes has been investigated. The plasma density and the electron temperature are raised around the second-harmonic resonance zone. And then, the ion saturation current is periodically increased with varying the position of the plate tuner. The distance between the peaks is nearly equal to half of the free-space wavelength of microwave. The efficiency of ECR has been improved by using the comb-shaped magnetic field and raising microwave frequency, and then the high-density plasma source has been accomplished at low microwave power.

• OSTI ID: 20861495
• Journal Information: Review of Scientific Instruments, Vol. 77, Issue 11; Other Information: DOI: 10.1063/1.2387885; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
AMPLIFIERS
CYLINDRICAL CONFIGURATION
EFFICIENCY
ELECTRON CYCLOTRON-RESONANCE
ELECTRON TEMPERATURE
GHZ RANGE 01-100
HIGH-FREQUENCY DISCHARGES
ION BEAMS
ION TEMPERATURE
MAGNETIC FIELD CONFIGURATIONS
MAGNETIC FIELDS
MICROWAVE RADIATION
PERMANENT MAGNETS
PLASMA
PLASMA DENSITY
TRAVELLING WAVE TUBES