Compact Plasma and Focused Ion Beams

Recent research has brought the application of microwaves from the classical fields of heating, communication, and generation of plasma discharges into the generation of compact plasmas that can be used for applications such as FIB and small plasma thrusters. However, these new applications bring with them a new set of challenges. With coverage ranging from the basics to new and emerging applications, Compact Plasma and Focused Ion Beams discusses how compact high-density microwave plasmas with dimensions smaller than the geometrical cutoff dimension can be generated and utilized for providing focused ion beams of various elements.

Starting with the fundamentals of the cutoff problem for wave propagation in waveguides and plasma diagnostics, the author goes on to explain in detail the plasma production by microwaves in a compact geometry and narrow tubes. He then thoroughly discusses wave interaction with bounded plasmas and provides a deeper understanding of the physics. The book concludes with an up-to-date account of recent research on pulsed microwaves and the application of compact microwave plasmas for multi-element FIB.

It provides a consolidated and unified description of the emerging areas in plasma science and technology utilizing wave-based plasma sources based on the author?s own work and experience. The book will be useful not only to established researchers in this area but will also serve as an excellent introduction to those interested in applying these ideas to various current and new applications.

IntroductionPlasma
Particle Interactions
Some Basic Plasma Properties
Criterion for the Definition of a Plasma
Different Types of Plasmas
Description of Plasmas
Theoretical Approaches
Microwave-Generated Plasmas
Compact Microwave Plasma Sources
Research Objective and Methods
References
Review of the Cutoff ProblemA Brief History of Earlier Work
Microwave Propagation in Waveguides
Plasma Density Cutoff
References
Plasma and Wave DiagnosticsPlasma Diagnostics with Langmuir’s Probes
Design of Electromagnetic Probes
References
Genesis of a Wave Induced Discharge: A New PerspectiveIntroduction
Historical Development of Breakdown Studies
Modeling of the Electron Dynamics
Development of the General Algorithm
Field-Free Case: Three-Dimensional Random Walk
Electron Transport in the Presence of an EM Field
Magnetostatically Assisted Electron Transport in the Presence of an EM Field
Electric Field Effects and the Random Walk Parameter
Linear and Circularly Polarized Waves
Summary and Conclusion
References
Plasma Production in Continuous-Mode Microwaves: Near-Circular MulticuspIntroduction
Apparatus
Multicusp Design
Waveguide Design
Experimental Results
Spatial Profiles of the Plasma
Discussion
Conclusions
References
Plasma Production in Continuous-Mode Microwaves: Rectangular Nonmulticusp WaveguideIntroduction
Experimental Procedures
Experimental Results
Discussion
Conclusions
References
Comparison of Square and Near-Circular Multicusp WaveguidesIntroduction
Waveguide Design
Experimental Results
Discussion
Conclusions
Summary of Experimental Results in Continuous-Mode Microwaves
Summary of the Plasma Production Mechanisms
References

Plasma Production in Pulsed-Mode Microwaves: General ExperimentIntroduction
Apparatus and Methods of the Experiment in a Circular Waveguide with a Dimension below Cutoff
Some Additional Details of the Experimental Set-Up
Probe for Measuring the Electric Field
Experimental Results
Discussion
Conclusions
References
Plasma Production in Pulsed-Mode Microwaves: Circular Multicusp Waveguide with a Dimension below CutoffIntroduction
Experimental Setup and Procedures
Experimental Results
Discussion
Conclusions
References
Plasma Buildup by Short-Pulse, High-Power MicrowavesIntroduction
Experiments
Discussion
Conclusion
References

Power Absorption and Intense Collimated Beam Production in a Pulsed High-Power Microwave Ion SourceIntroduction
Ion Source Design and Experimental Setup
Experimental Results
Discussion
Conclusions
Summary in Pulsed Microwaves
References
New Experiments in Continuous-Mode Microwaves: Formation of Standing Waves and Electron TrappingOverview of the New Experimental System
Introduction
Spatial Plasma Characteristics
Axial Wave Field Intensity Measurements
Electron Trapping in SW Minima
Model Calculation
Summary and Discussion
References
Penetration and Screening of Perpendicularly Launched Electromagnetic WavesIntroduction
Experimental Setup
Experimental Observation
Modeling
Modeling Results
Discussion and Summary
References
Wave Birefringence in Perpendicular PropagationIntroduction
Polar Plasma Characteristics
Polar Wave Field Intensity Measurements
Modeling of the Wave Birefringence
Discussion and Summary
References
Electron Localization and Trapping Physics RevisitedIntroduction
Experimental Setup
Experimental Results
Modeling
Modeling Results
Summary and Discussion
References
New Experiments in Pulsed Microwaves: Quasisteady-State Interpulse PlasmasIntroduction
Experiment
Experimental Results
Model Calculation
Discussion and Conclusion
References
Electron Plasma Waves Inside Large-Amplitude Electromagnetic PulsesIntroduction
Experimental Setup
Experimental Results
Time–Frequency Analysis
Model
Summary
References
Transition from Interpulse to Afterglow PlasmasIntroduction
Experimental Setup
Results
Summary
References
Introduction to Focused Ion BeamsFocused Ion Beams
References

Experimental Setup for Basic Plasma StudiesIntroduction
Basic Plasma Experiments
Measurement of Plasma Parameters
Sub-Cutoff Dimensional Plasma Sources
Conclusion
References
Basic Beam Studies: Extraction and Ion Energy DistributionIntroduction
Experiment
Results and Discussion
Conclusion
References
Multielement Focused Ion BeamIntroduction
Beam Column of MEFIB
Beam Simulation Codes
Results and Discussion
Tolerance Studies
Conclusion
References
Focused Ion Beam ExperimentsIntroduction
Results and Discussion
Conclusion
References
Summary and Future Prospects
Index