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Radio frequency ion source operated with field effect transistor based radio frequency system
1Department of Electrical Engineering, Tohoku University, Sendai 980-8759, Japan. akira@ecei.tohoku.ac.jp
The Review of Scientific Instruments
|March 3, 2010
Summary
Radio frequency plasma production achieved high electron densities in argon and hydrogen using a field effect transistor inverter. An axial magnetic field significantly boosted hydrogen plasma density.
Area of Science:
- Plasma Physics
- Electrical Engineering
Background:
- Radio frequency (RF) plasma generation is crucial for various industrial applications.
- Efficiently producing high-density plasmas requires optimized power sources and conditions.
Purpose of the Study:
- To investigate radio frequency (RF) plasma production characteristics using a field effect transistor (FET) inverter power supply.
- To explore the influence of magnetic fields and gas pressure on plasma density.
Main Methods:
- Utilized a FET inverter as an RF wave source operating at approximately 0.3 MHz.
- Measured electron density in argon and hydrogen plasmas under varying conditions, including the application of an axial magnetic field (around 100 G).
Main Results:
- Achieved electron densities exceeding 10^18 m^-3 in argon plasma.
- Observed lower densities in hydrogen plasma, which increased to 5x10^18 m^-3 with an applied axial magnetic field.
- Investigated the effects of magnetic field strength and gas pressure on RF plasma parameters.
Conclusions:
- FET inverter power supplies are effective for RF plasma generation.
- Axial magnetic fields can significantly enhance plasma density, particularly in hydrogen.
- Further research is warranted to optimize RF plasma production for specific applications.
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