Handbook of Vacuum Science and Technology (eBook)

Cover 1
Contents 10
Preface 18
List of Contributors 22
Part 1: Fundamentals of Vacuum Technology and Surface Physics 26
Chapter 1.1. Vacuum Nomenclature and Definitions 28
1.1.1 Basic Definition 28
1.1.2 Pressure Regions of Vacuum 28
Chapter 1.2. Gas Properties 33
1.2.1 Description of Vacuum as a Low-Pressure Gas 33
1.2.2 Characteristics of a Gas„Basic Definitions 33
1.2.3 Gas Laws 34
Chapter 1.3. Molecular Processes and Kinetic Theory 36
1.3.1 General Description 36
1.3.2 Molecular Motion 37
1.3.3 Kinetic Theory Derivation of the Gas Laws 39
1.3.4 Pressure 40
1.3.5 Molecular Mean Free Path 42
1.3.6 Number of Impacts with the Chamber Wall 44
1.3.7 Time to Form a Monolayer 45
1.3.8 Thermal Transpiration 45
1.3.9 Coefficient of Thermal Conductivity 46
1.3.10 Coefficient of Diffusion 46
Chapter 1.4. Throughput, Pumping Speed, Evacuation Rate, Outgassing Rate, and Leak Rate 47
Chapter 1.5. Gas Flow 50
1.5.1 Nature of Gas Flow 50
1.5.2 Turbulent Flow 52
1.5.3 Viscous, Streamline, or Laminar Flow 53
1.5.4 Molecular Flow 54
1.5.5 Flow Relationships 54
Chapter 1.6. Conductance 57
1.6.1 Conductance 57
1.6.2 Conductances in Parallel 58
1.6.3 Conductances in Series 58
Chapter 1.7. Flow Calculations 60
1.7.1 Equations for Viscous Flow 60
1.7.2 Equations for Molecular Flow 62
1.7.3 Knudsen's Formulation 62
1.7.4 Clausing Factors 63
Chapter 1.8. Surface Physics and Its Relation to Vacuum Science 65
1.8.1 Physical Adsorption or "Adsorption" 65
1.8.2 Chemisorption 67
1.8.3 Sticking Coefficient 68
1.8.4 Surface Area 69
1.8.5 Surface Adsorption Isotherms 70
1.8.6 Capillary Action 72
1.8.7 Condensation 73
1.8.8 Desorption Phenomena 74
1.8.9 Thermal Desorption 75
1.8.10 Photoactivation 77
1.8.11 Ultrasonic Desorption 78
1.8.12 Electron- and Ion-Stimulated Desorption 78
1.8.13 Gas Release from Surfaces 79
References 80
Part 2: Creation of Vacuum 82
Chapter 2.1. Technology of Vacuum Pumps „ An Overview 84
2.1.1 Vacuum Pump Function Basics 84
2.1.2 Gas Transport: Throughput 86
2.1.3 Performance Parameters 87
2.1.4 Pumping Speed 89
2.1.5 Pumpdown Time 90
2.1.6 Ultimate Pressure 94
2.1.7 Forevacuum and High-Vacuum Pumping 96
2.1.8 Pump System Relationships 98
2.1.9 Crossover from Rough to High-Vacuum Pumps 103
2.1.10 Pumping System Design 104
References 108
Chapter 2.2. Diaphragm Pumps 109
2.2.1 Introduction: Basics and Operating Principle 109
2.2.2 State-of-the-Art Design and Manufacturing 112
2.2.3 Performance and Technical Data 116
2.2.4 Modular Concept for Specific Application Setups: Standalone Operation 117
2.2.5 Diaphragm Pumps as Backing and Auxiliary Pumps in Vacuum Systems 118
References 121
Chapter 2.3. Vacuum Blowers 122
2.3.1 Introduction 122
2.3.2 Equipment Description 122
2.3.3 Blower Operating Principle 125
2.3.4 Blower Pumping Efficiency 126
2.3.5 Blower Pumping Speed Calculations 128
2.3.6 Power Requirements 129
2.3.7 Temperature Considerations 131
2.3.8 Flow and Compression Ratio Control Mechanisms 133
2.3.9 Liquid-Sealed Blowers 137
2.3.10 Selected System Arrangements 137
Chapter 2.4. Vacuum Jet Pumps (Diffusion Pumps) 141
2.4.1 Basic Pumping Mechanism 142
2.4.2 Pumping Speed 147
2.4.3 Throughput 152
2.4.4 Tolerable Forepressure 153
2.4.5 Ultimate Pressure 157
2.4.6 Backstreaming 162
2.4.7 Other Performance Aspects 169
References 173
Chapter 2.5. Cryogenic Pumps 174
2.5.1 Introduction 174
2.5.2 Cryopump Basics 181
2.5.3 Advanced Control Systems 192
2.5.4 Cryopump Process Applications 198
2.5.5 Cryogenic Pumps Specifically for Water Vapor 202
2.5.6 Comparison of Cryopumps to Other Types of Pumps 204
2.5.7 Future Developments 206
References 206
Chapter 2.6. Turbomolecular Pumps 208
2.6.1 Turbomolecular Pumps (TMP) 208
2.6.2 Molecular Drag Pumps (MDP) 220
2.6.3 Combination of Pumps (TMP + MDP) 222
2.6.4 Evaluation of Combinations of Backing Pumps and TMPs, Etc 225
2.6.5 The Use of TMP in Applications: Specific Effects and Demands 233
2.6.6 Avoiding Operational Mistakes 236
References 237
Chapter 2.7. Pumps for Ultra-High Vacuum Applications 239
2.7.1 System Design for Ultra-High Vacuum 240
2.7.2 The Selection of Pumps for Ultra-High Vacuum Applications 241
2.7.3 Sputter-Ion Pumps 245
2.7.4 Getter Pumps 267
References 277
Part 3: Vacuum Measurements 280
Chapter 3.1. The Measurement of Low Pressures 282
3.1.1 Overview 283
3.1.2 Direct Reading Gauges 285
3.1.3 Indirect Reading Gauges 290
3.1.4 Calibration of Vacuum Gauges 311
References 313
Chapter 3.2. Mass Analysis and Partial Pressure Measurements 315
3.2.1 Overview and Applications 315
3.2.2 Inlet Systems 325
3.2.3 Ion Generation and Ion Sources 328
3.2.4 Ion Separation Analyzers 333
3.2.5 Detection of Ions 348
References 351
Chapter 3.3. Practical Aspects of Vacuum System Mass Spectrometers 360
3.3.1 Historical Insight 360
3.3.2 Expected Gases in a Vacuum System 361
3.3.3 The Ion Generation Process 365
3.3.4 Techniques for Analysis 376
3.3.5 Calibration of Vacuum System Mass Spectrometers 389
3.3.6 Some Applications 395
References 399
Chapter 3.4. Mass Flow Measurement and Control 401
3.4.1 General Principles of Mass Flow Measurement 401
3.4.2 Overview of Thermal Mass Flow Controller Technology 403
3.4.3 Performance Characteristics 407
3.4.4 Troubleshooting 411
References 412
Part 4: Systems Design and Components 414
Chapter 4.1. Selection Considerations for Vacuum Valves 416
4.1.1 Introduction 416
4.1.2 Valves for Shutoff 416
4.1.3 Valves for Control 422
4.1.4 Valve Construction 423
4.1.5 Specialty Valves 429
4.1.6 Installation Considerations for Vacuum Valves 432
References 433
Chapter 4.2. Flange and Component Systems 434
4.2.1 Introduction 434
4.2.2 Selecting a Flange System 435
4.2.3 Common Flange Systems 435
4.2.4 Components with Flanges Attached 450
Trademarks 455
References 457
Chapter 4.3. Magnetic-Fluid-Sealed Rotary Motion Feedthroughs 458
4.3.1 Basic Sealing Principle 458
4.3.2 Application Factors 459
4.3.3 Impact of Feedthrough on Process 461
4.3.4 Impact of Process on Feedthrough 462
4.3.5 Materials Considerations 463
4.3.6 Application Examples 465
4.3.7 Comparison to Other Types of Feedthroughs 467
Chapter 4.4. Viewports 469
4.4.1 Materials 469
4.4.2 Mounting Systems and Precautions 470
CH4Chapter 4.5. Construction Materials 471
4.5.1 Properties Defining Material Performance 471
4.5.2 Vacuum Chamber Materials 476
4.5.3 Special-Purpose Materials 480
References 487
Chapter 4.6. Demountable Seals for Flanges and Valves 488
4.6.1 Sealing Overview: Polymer and Metal Seals 488
4.6.2 The Elastomeric and Nonelastomeric Polymers Used in Vacuum Sealing 489
4.6.3 Metal Seals 499
References 507
Chapter 4.7. Outgassing of Materials 509
4.7.1 Relationships Among System Pressure, Pumping Speed, and Outgassing 509
4.7.2 Initial Pumpdown from Atmospheric Pressure 519
4.7.3 Pressure Vs. Time During Outgassing 520
4.7.4 The Outgassing Rate of Elastomers and Plastics 522
4.7.5 The Outgassing Rate of Metals and Ceramics 526
4.7.6 The Outgassing Rate of Preconditioned Vacuum Systems After Short Exposure to the Atmosphere 529
4.7.7 Methods of Decreasing the Outgassing Rate 531
4.7.8 Measurement of the Outgassing Rate of Materials 532
References 533
Chapter 4.8. Aluminum-Based Vacuum Systems 534
4.8.1 Outgassing 534
4.8.2 Demountable Seals 537
4.8.3 Cleaning and Surface Finishing 543
4.8.4 Mechanical Considerations 545
4.8.5 Thermal Conductivity and Emissivity 561
4.8.6 Corrosion 563
4.8.7 Welding Aluminum for Vacuum Applications 566
References 573
Chapter 4.9. Preparation and Cleaning of Vacuum Surfaces 578
4.9.1 Surface Modification 579
4.9.2 External Cleaning 592
4.9.3 Assembly, Handling, and Storage 612
4.9.4 In Situ Cleaning 616
4.9.5 Documentation 624
4.9.6 Conclusion 626
Trade Names 626
References 626
Part 5: Vacuum Applications 632
Chapter 5.1. High-Vacuum-Based Processes: Sputtering 634
5.1.1 Sputtering and Deposition 636
5.1.2 Sputter Deposition Technologies 637
5.1.3 Magnetron Applications 649
5.1.4 Future Directions in Sputtering 651
References 652
Chapter 5.2. Plasma Etching 653
5.2.1 Introduction 653
5.2.2 Review of Plasma Concepts Applicable to Etching Reactors 653
5.2.3 Basic Plasma Etching Requirements 658
5.2.4 Plasma Diagnostics 666
5.2.5 Basic Plasma Etch Reactors 668
5.2.6 Advanced Plasma Etch Reactors 674
5.2.7 New Trends 690
References 692
Chapter 5.3. Ion Beam Technology 697
5.3.1 Introduction 697
5.3.2 Ion Beam Etching 703
5.3.3 Ion Beam Sputter Deposition 708
5.3.4 lon-Beam-Assisted Deposition 712
5.3.5 Ion Beam Direct Deposition 714
5.3.6 Conclusion 715
References 716
Chapter 5.4. Pulsed Laser Deposition 719
5.4.1 Introduction 719
5.4.2 Pulsed Laser Deposition System 720
5.4.3 The Ablation Mechanism 723
5.4.4 Advantages and Limitations 725
5.4.5 Materials Survey 730
5.4.6 Future Outlook 733
References 733
Chapter 5.5. Plasma-Enhanced Chemical Vapor Deposition 736
5.5.1 Introduction 736
5.5.2 Equipment and Other Practical Considerations 742
5.5.3 Process Scaleup 748
5.5.4 Conclusion 752
References 753
Chapter 5.6. Common Analytical Methods for Surface and Thin Film 756
5.6.1 Introduction 756
5.6.2 The Electron Spectroscopies 757
5.6.3 Methods Based on Ion Bombardment 770
5.6.4 UHV Generation and System Considerations for Surface Analysis 780
References 782
Part 6: Large-Scale Vacuum-Based Processes 784
Chapter 6.1. Roll-to-Roll Vacuum Coating 786
6.1.1 Overview of Roll-to-Roll Vacuum Coating 786
6.1.2 Typical Products 789
6.1.3 Materials and Deposition Processes Commonly Used in Roll-to-Roll Coating 790
6.1.4 Vacuum Systems for Roll-to-Roll Coating Applications 800
6.1.5 Substrates (Webs) 804
6.1.6 Process Control 808
6.1.7 Specific Problems Exhibited by Coatings 809
References 812
Chapter 6.2. The Development of Ultra-High-Vacuum Technology for Particle Accelerators and Magnetic Fusion Devices 814
6.2.1 Introduction 814
6.2.2 Storage Rings and the Need for UHV 815
6.2.3 UHV for Early Storage Rings 818
6.2.4 Storage Ring Vacuum Vessel and Pumping System Developments 821
6.2.5 Cold-Bore Machines 823
6.2.6 Superconducting RF Accelerators 825
6.2.7 The Next-Generation Big Accelerator? 826
6.2.8 The Magnetic Fusion Road Map 826
6.2.9 The Early History of Magnetic Fusion 828
6.2.10 Model C: The First UHV Fusion Device 829
6.2.11 The Russian Revolution in Fusion: Tokamaks 830
6.2.12 Plasma Impurities and Vacuum Technology 831
6.2.13 Toward the Breakeven Demonstrations 833
6.2.14 The Next Step in Fusion 835
Acknowledgments 835
References 837
Index 840