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Analysis of electron energy distribution function in the Linac4 H⁻ source
S Mochizuki1, S Mattei2, K Nishida1
1Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
The Review of Scientific Instruments
|March 3, 2016
Summary
Understanding the Electron Energy Distribution Function (EEDF) in Radio Frequency Inductively Coupled Plasmas (RF-ICPs) is key. Lowering gas pressure in hydrogen negative ion sources can boost molecule dissociation and H(-) ion production.
Area of Science:
- Plasma Physics
- Atomic and Molecular Physics
Background:
- Radio Frequency Inductively Coupled Plasmas (RF-ICPs) are crucial for generating negative ions.
- Understanding the Electron Energy Distribution Function (EEDF) is vital for optimizing plasma processes.
Purpose of the Study:
- To analyze the EEDF in hydrogen negative ion sources within RF-ICP environments.
- To investigate the relationship between EEDF characteristics and negative ion production.
Main Methods:
- Numerical simulations were employed to model the EEDF.
- Theoretical analysis using the Boltzmann equation validated simulation results.
Main Results:
- The EEDF in RF-ICPs exhibits a two-part structure: a Maxwellian low-energy component and a non-Maxwellian high-energy component.
- Simulation findings were corroborated by analytical approaches.
Conclusions:
- Reducing gas pressure is a viable strategy to enhance molecular dissociation.
- Lowering gas pressure can significantly increase the production of H(-) negative ions.
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