The Physics and Technology of Ion Sources 2e

Dr. Ian G. Brown is a retired Senior Physicist at Lawrence Berkeley National Laboratory.

Preface. List of Contributors. 1. Introduction (Ian Brown). 2. Plasma Physics (Ian Brown). 2.1 Introduction. 2.2 Basic Plasma Parameters. 2.2.1 Particle Density. 2.2.2 Fractional Ionization. 2.2.3 Particle Temperature. 2.2.4 Particle Energy and Velocity. 2.2.5 Collisions. 2.3 The Plasma Sheath. 2.3.1 Debye Length. 2.3.2 Charge Neutrality. 2.3.3 Plasma Oscillations. 2.4 Magnetic Field Effects. 2.4.1 Gyro Orbits. 2.4.2 Gyro Frequencies. 2.4.3 Magnetic Confinement. 2.4.4 Magnetic and Plasma Pressure. 2.5 Ionization. 2.5.1 Electron Impact Ionization. 2.5.2 Multiple Ionization. 2.5.3 Photoionization. 2.5.4 Ion Impact Ionization. 2.5.5 Negative Ions. 2.5.6 Field Ionization. 3. Elementary Ion Sources (Ian Brown). 3.1 Introduction. 3.2 Terminology. 3.3 The Quintessential Ion Source. 3.4 Ion Beam Formation. 3.5 Ion Beam Parameters. 3.6 An Example. 3.7 Conclusion. 4. Computer Simulation of Extraction (Peter Spdtke). 4.1 Introduction. 4.2 Positive Ion Sources. 4.2.1 Filament Driven Cusp Sources. 4.2.2 Duoplasmatrons and Duopigatrons. 4.2.3 Vacuum Arc Ion Sources. 4.2.4 Laser Ion Sources. 4.2.5 ECR Ion Sources. 4.2.6 Penning Ion Sources. 4.3 Negative Ion and Electron Sources. 4.3.1 Hot Cathode Electron Sources. 4.3.2 Plasma Electron Sources. 4.3.3 H Sources. 4.4 Conclusion 5. Ion Extraction (Ralph Hollinger). 5.1 Introduction. 5.2 Fundamentals of Ion Beam Formation in the Extraction System. 5.3 Beam Quality. 5.4 Sophisticated Treatment of Ion Beam Formation in the Extraction System. 5.5 Multi Aperture Extraction Systems. 5.6 Starting Conditions. 6. Beam Transport (Peter Spdtke and Ralph Hollinger). 6.1 Introduction. 6.1.1 Drift. 6.1.2 Extraction System and Acceleration Gap. 6.1.3 Low Energy Beam Line. 6.2 Current Effects. 6.3 Space Charge Compensation. 6.3.1 Residual Gas Collisions. 6.3.2 Sputtering. 6.3.3 Preserving Space Charge Compensation. 6.3.4 Influence of Space Charge Compensation. 6.4 A LEBT System for the Future Proton Linac at GSI. 6.4.1 Compound System. 6.4.2 Pentode or Two Gap System. 6.4.3 Triode System and DCPost A cceleration. 6.4.4 Discussion. 7. High Current Gaseous Ion Sources (Nikolai Gavrilov). 7.1 Introduction. 7.2 Basic Types of High Current Ion Sources. 7.2.1 Filament Driven Ion Sources. 7.2.2 High Frequency Ion Sources. 7.2.3 Cold Cathode Ion Sources. 7.3 Conclusion. 8. Freeman and Bernas Ion Sources (Marvin Farley, Peter Rose, and Geoffrey Ryding). 8.1 Introduction. 8.2 The Freeman Ion Source. 8.3 The Bernas Ion Source. 8.4 Further Discussion of the Source Plasma. 8.4.1 Plasma and Sheath Potentials. 8.4.2 Effect of Sputtering on the Plasma. 8.4.3 Ion Heating of the Cathode and Anticathode in the Bernas Source. 8.4.4 Current Balance in the Freeman Source. 8.4.5 Current Balance in the Bernas Source. 8.5 Control Systems. 8.5.1 Freeman and Bernas Controls. 8.5.2 Bernas Indirectly Heated Cathode. 8.6 Lifetime and Maintenance Issues. 8.6.1 Use of BF3. 8.6.2 Use of PH3, AsH3, P4, and As4. 8.6.3 Use of Sb, Sb2O3, and SbF3. 8.6.4 Use of SiF4 and GeF4. 8.6.5 General Guidelines for the Use of Other Organic and Inorganic Compounds. 8.6.6 Electrode Cleaning and Maintenance. 8.6.7 Insulator Cleaning and Maintenance. 9. Radio Frequency Driven Ion Sources (Ka Ngo Leung). 9.1 Introduction. 9.2 Capacitively Coupled RF Sources. 9.3 Inductively Coupled RF Sources. 9.3.1 Source Operation with an External RF Antenna. 9.3.2 Multicusp Source Operation with Internal RF Antenna. 9.3.3 Increasing the Ion Beam Brightness of a Multicusp RF Source with Internal Antenna. 9.3.4 Multicusp Source Operation with External RF Antenna. 9.4 Applications of RF Ion Sources. 10. Microwave Ion Sources (Noriyuki Sakudo). 10.1 Introduction. 10.2 Microwave Plasma in Magnetic Fields. 10.2.1 Plasma Parameter Changes due to Magnetic Field and Microwave Frequency. 10.2.2 High Density Plasma at Off Resonance. 10.3 Some Practical Ion Source Considerations. 10.3.1 Microwave Impedance Matching to the Plasma. 10.3.2 High Current Ion Beams Extracted from an Off Resonance Microwave Ion Source. 10.4 Versatility of Beam Extraction. 10.4.1 Large Cross Sectional Beam formed by a Multi Aperture Extractor. 10.4.2 Slit Shaped Beam for Ion Implantation. 10.4.3 Further Improvements in Slit Shaped Beams. 10.4.4 Compact Microwave Ion Sources. 10.5 Diversity of Available Ion Species. 10.6 Microwave Ion Sources for Commercial Implanters. 10.6.1 Semiconductor Device Fabrication. 10.6.2 SOI Wafer Fabrication. 10.7 Conclusion. 11. ECR Ion Sources (Daniela Leitner and Claude Lyneis). 11.1 Introduction. 11.2 Brief History of the Development of ECR Ion Sources. 11.3 The LBNL ECR Ion Sources. 11.3.1 The AECR U Ion Source. 11.3.2 The VENUS ECR Ion Source. 11.4 Physics and Operation of ECR Ion Sources. 11.4.1 Electron Impact Ionization. 11.4.2 Charge Exchange. 11.4.3 Plasma Confinement. 11.4.4 ECR Heating. 11.4.5 Gas Mixing. 11.5 Design Considerations. 11.6 Microwave and Magnetic Field Technologies. 11.7 Metal Ion Beam Production. 11.7.1 Direct Insertion. 11.7.2 Sputtering. 11.7.3 Gaseous or Volatile Compounds (MIVOC Method). 11.7.4 External Furnaces (Ovens). 11.7.5 Efficiencies. 11.8 Ion Beam Extraction from ECR Ion Sources. 11.8.1 Influence of Magnetic Field and Ion Temperature on the Extracted Ion Beam Emittance. 11.8.2 Influence of Plasma Confinement on Beam Emittance. 11.9 Conclusion. 12. Laser Ion Sources (Boris Sharkov). 12.1 Introduction. 12.2 Basics of Laser Plasma Physics. 12.3 General Description. 12.3.1 Laser Characteristics. 12.3.2 Target Illumination System. 12.3.3 Target Ensemble. 12.3.4 Pulse Width and Target Extractor Separation. 12.3.5 Extraction System. 12.3.6 Low Energy Beam Transport Line (LEBT). 12.4 Beam Parameters. 12.4.1 Current Profile. 12.4.2 Charge State Distribution. 12.4.3 Beam Emittance. 12.4.4 Pulse Stability and Source Lifetime. 12.5 Sources at Accelerators. 12.5.1 The LIS at ITEP TWAC. 12.5.2 The LIS at CERN. 12.5.3 The LIS at JINR Dubna. 12.6 Other Operating Options. 12.6.1 High Current, Low Charge State Mode. 12.6.2 Influence of Magnetic Field on the Laser Ion Source Plasma. 12.7 Conclusion. 13. Vacuum Arc Ion Sources (Efim Oks and Ian Brown). 13.1 Introduction. 13.2 Background. 13.3 Vacuum Arc Plasma Physics. 13.4 Principles of Operation. 13.5 Beam Parameters. 13.5.1 Beam Current. 13.5.2 Beam Profile, Divergence and Emittance. 13.5.3 Beam Composition. 13.5.4 Beam Noise, Pulse Stability, and Lifetime. 13.6 Recent Improvements in Parameters and Performance. 13.6.1 Enhancement of Ion Charge States. 13.6.2 Alternative Triggering of the Vacuum Arc. 13.6.3 Reduction in Ion Beam Noise and Increased Pulse Stability. 13.6.4 Generation of Gaseous Ions. 13.7 Source Embodiments. 13.7.1 LBNL Mevva Sources. 13.7.2 HCEI Titan Sources. 13.7.3 NPI Raduga Sources. 13.7.4 GSI Varis Sources. 13.7.5 Other Versions and Variants. 13.8 Conclusion. 14. Negative Ion Sources (Junzo Ishikawa). 14.1 Introduction. 14.2 Surface Effect Negative Ion Sources. 14.2.1 Negative Ion Production by Surface Effect. 14.2.2 Surface Effect Light Negative Ion Sources. 14.2.3 Surface Effect Heavy Negative Ion Sources. 14.3 Volume Production Negative Ion Sources. 14.3.1 Negative Ion Formation by Volume Production. 14.3.2 History of Source Development. 14.3.3 Recent Volume Production Negative Ion Sources. 14.4 Charge Transfer Negative Ion Sources. 14.4.1 Negative Ion Production by Charge Transfer. 14.4.2 History of Charge Transfer Negative Ion Sources. 14.5 Conclusion. 15. Ion Sources for Heavy Ion Fusion (Joe Kwan). 15.1 Introduction. 15.1.1 Heavy Ion Beam Driven Inertial Fusion. 15.1.2 HIF Ion Source Requirements. 15.2 Beam Extraction and Transport. 15.2.1 Scaling Laws for Beam Extraction and Transport. 15.2.2 Large Beam vs. Multiple Small Beamlets. 15.3 Surface Ionization Sources. 15.3.1 Contact Ionizers. 15.3.2 Aluminosilicate Sources. 15.3.3 Surface Ionization Sources for HIF. 15.4 Gas Discharge Ion Sources for HIF. 15.5 Pulsed Discharge Sources. 15.5.1 Metal Vapor Vacuum Arc Sources for HIF. 15.8.1 Laser Ion Sources for HIF. 15.6 Negative Ion Sources for HIF. 15.7 HIF Injector Designs. 15.7.1 Large Diameter Source Approach. 15.7.2 Merging Multiple Beamlets Approach. 15.8 Conclusion. 16. Giant Ion Sources for Neutral Beams (Yasuhiko Takeiri). 16.1 Introduction. 16.2 Large Volume Plasma Production. 16.2.1 Bucket Plasma Sources with Multi Cusp Magnetic Field. 16.2.2 Plasma Modeling. 16.2.3 Atomic Fraction. 16.3 Large Area Beam Extraction and Acceleration. 16.3.1 Electrode Systems for Large Area Beams. 16.3.2 Beamlet Steering. 16.4 Giant Positive Ion Sources. 16.5 Giant Negative Ion Sources. 16.5.1 Operational Principles of Negative Ion Sources. 16.5.2 Negative Ion Extraction and Acceleration. 16.5.3 Giant Negative Ion Sources. 16.6 Future Directions of Development. Appendices. Appendix 1: Physical Constants. Appendix 2: Some Plasma Parameters. Appendix 3: Table of the Elements. Index.