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Electrical characterization of a capacitive rf plasma sheath
1National Center for Plasma Science and Technology, School of Physical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland. david.gahan@dcu.ie
The Review of Scientific Instruments
|May 17, 2007
Summary
This study presents a novel experimental system for analyzing radio frequency (RF) sheaths in plasma reactors. The system decouples the electrode sheath from plasma parameters, enabling detailed sheath investigation under various bias conditions.
Area of Science:
- Plasma Physics
- Electrical Engineering
- Materials Science
Background:
- Radio frequency (RF) sheaths are critical interfaces in plasma processing.
- Understanding sheath behavior is essential for controlling plasma-surface interactions.
- Existing methods often perturb bulk plasma parameters during sheath investigation.
Purpose of the Study:
- To develop and characterize an experimental system for investigating capacitive RF sheaths.
- To decouple the electrode sheath from bulk plasma parameters for independent analysis.
- To study power coupling and electron conduction currents within the sheath.
Main Methods:
- Utilized an inductive plasma reactor with a specialized electrode.
- Employed separate radio frequency (RF) and direct current (DC) power sources for independent control.
- Investigated sheath characteristics under varying DC bias conditions without perturbing bulk plasma.
Main Results:
- Successfully decoupled the electrode sheath from plasma parameters.
- Enabled detailed investigation of sheath properties under different bias conditions.
- Presented a method to determine electron conduction current using external DC bias.
Conclusions:
- The developed system offers a powerful tool for characterizing RF sheaths.
- Decoupling sheath and plasma parameters allows for precise control and analysis.
- The method for determining electron conduction current provides valuable insights into sheath physics.
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