Physics of Quantum Electron Devices

1. Introduction.- 1.1 A Perspective on the Evolution of Quantum Semiconductor Devices.- 1.2 Outline of the Book.- References.- 2. The Nature of Molecular Beam Epitaxy and Consequences for Quantum Microstructures.- 2.1 Dimensional Confinement and Device Concepts.- 2.2 Molecular Beam Epitaxy.- 2.2.1 Conceptual Picture.- 2.2.2 Reflection High Energy Electron Diffraction.- 2.2.3 Formation of Interfaces and Growth Interruption.- 2.3 The Surface Kinetic Processes and Computer Simulations of Growth.- 2.3.1 The CDRI Model.- 2.3.2 Growth Front Morphology.- 2.3.3 The CDRI Model and the Nature of GaAs/AlxGa1?xAs (100) Interfaces.- 2.4 Quantum Wells: Growth and Photoluminescence.- 2.5 Concluding Remarks.- 2.6 Recent Advances.- References.- 3. Nanolithography for Ultra-Small Structure Fabrication.- 3.1 Overview.- 3.2 Resolution Limits of Lithographic Processes.- 3.2.1 Lithography.- 3.2.2 Resolution Limits of Lithographic Methods.- 3.2.3 Photolithography and X-Ray Lithography.- 3.2.4 Ion Beams.- 3.2.5 Electron Beams.- 3.3 Pattern Transfer.- References.- 4. Theory of Resonant Tunnelling and Surface Superlattices.- 4.1 Tunnelling Probabilities.- 4.1.1 Single Barrier.- 4.1.2 Resonant Tunnelling Rates.- 4.2 Tunnelling Time.- 4.3 Pseudo-Device Calculations.- 4.3.1 The Wigner Function.- 4.3.2 Diode Response.- 4.4 Lateral Superlattices.- 4.4.1 Transport Effects.- 4.4.2 Bloch Oscillators.- 4.4.3 High Frequency Response.- References.- 5. The Investigation of Single and Double Barrier (Resonant Tunnelling) Heterostructures Using High Magnetic Fields.- 5.1 Background.- 5.2 LO Phonon Structure in the I(V) and C(V) Curves of Reverse-Biased Heterostructures.- 5.2.1 n-GaAs/(AlGa)As/GaAs Heterostructures.- 5.2.2 n-(InGa)As/InP/(InGa)As Heterostructures.- 5.2.3 Magnetocapacitance and Magnetic Freeze-out.- 5.3 Magnetotunnelling from the 2D Electron Gas in Accumulated (InGa)As/InP Structures Grown by MBE and MOCVD.- 5.4 Observation of Magnetoquantized Interface States by Electron Tunnelling in Single-Barrier n? (InGa)As/InP/n+ (InGa)As Heterostructures.- 5.5 Box Quantised States.- 5.6 Double Barrier Resonant Tunnelling Devices.- 5.6.1 Hybrid Magneto-electric States in Resonant Tunnelling Structures.- 5.6.2 Intrinsic Bistability in Resonant Tunnelling Devices.- 5.6.3 Magnetic Field Studies of Elastic Scattering and Optic Phonon Emission in Resonant Tunnelling Devices.- References.- 6. Microwave and Millimeter-Wave Resonant-Tunnelling Devices.- 6.1 Speed of Response.- 6.2 Resonant-Tunnelling Oscillators.- 6.3 Self-Oscillating Mixers.- 6.4 Resistive Multipliers.- 6.5 Variable Absolute Negative Conductance.- 6.6 Persistent Photoconductivity and a Resonant-Tunnelling Transistor.- 6.7 A Look at Resonant-Tunnelling Theory.- 6.7.1 Stationary-State Calculation.- 6.7.2 Temporal Behavior.- 6.7.3 Scattering.- 6.8 Concluding Remarks.- Note Added in Proof.- List of Symbols.- References.- 7. Resonant Tunnelling and Superlattice Devices: Physics and Circuits.- 7.1 Resonant Tunnelling Through Double Barriers and Superlattices.- 7.1.1 The Origin of Negative Differential Resistance.- 7.1.2 Coherent (Fabry-Perot-Type) Resonant Tunnelling.- 7.1.3 The Role of Scattering: Sequential Resonant Tunnelling Through Double Barriers and Superlattices.- 7.1.4 Ga0.47In0.53As/Al0.48In0.52As Resonant Tunnelling Diodes.- 7.1.5 Resonant Tunnelling Through Parabolic Quantum Wells.- 7.1.6 Resonant Tunnelling Electron Spectroscopy.- 7.2 Application of Resonant Tunnelling: Transistors and Circuits.- 7.2.1 Integration of Resonant Tunnelling Diodes and Their Circuit Applications.- a) Horizontal Integration of RT Diodes.- b) Vertical Integration of RT Diodes.- 7.2.2 Resonant Tunnelling Bipolar Transistors.- a) Circuit Applications of RTBTs.- b) Resonant Tunnelling Bipolar Transistors Operating at Room Temperature.- c) Alternative Designs of RTBTs.- d) RTBT with Multiple Peak Characteristics.- 7.2.3 Resonant Tunnelling Unipolar Transistors.- a) Resonant Tunnelling Gate Field Effect Transistor.- b) Quantum Wire Transistor.- c) The Gated Quantum Well Resonant Tunnelling Transistor.- References.- 8. Resonant-Tunnelling Hot Electron Transistors (RHET).- 8.1 RHET Operation.- 8.2 RHET Technology Using GaAs/AlGaAs Heterostructures.- 8.3 InGaAs-Based Material Evaluation.- 8.4 RHET Technology Using InGaAs-Based Materials.- 8.5 Theoretical Analyses of RHET Performance.- 8.6 Summary.- References.- 9. Ballistic Electron Transport in Hot Electron Transistors.- 9.1 Ballistic Transport.- 9.1.1 The Search for Ballistic Transport.- 9.1.2 Properties of GaAs.- 9.2 Hot Electron Transistors.- 9.2.1 Principles of Operation.- 9.2.2 Some History.- 9.3 Hot Electron Injectors.- 9.3.1 What is a Hot Electron Injector?.- 9.3.2 The Thermionic Injector.- 9.3.3 The Tunnel Injector.- 9.4 Energy Spectroscopy.- 9.4.1 Spectroscopy Defined.- 9.4.2 Band Pass Spectrometer.- 9.4.3 High Pass Spectrometer.- 9.4.4 Energy Resolution of the Square Type Barrier.- 9.4.5 Observation of Quasi Ballistic and Ballistic Electron Transport in GaAs.- 9.4.6 Observation of Ballistic Hole Transport in GaAs.- 9.5 Electron Coherent Effects in the THETA Device.- 9.5.1 Size Quantization Effects.- 9.5.2 Classical and Self-Consistent Well Potential.- 9.5.3 Tunnelling into a Well.- 9.5.4 Nonparabolicity Effects, Real and Resonant States.- 9.5.5 Interference Effects of Ballistic Holes.- 9.6 Transfer to the L Satellite Valleys.- 9.6.1 Spectroscopic Observations.- 9.6.2 Verification of the Intervalley Transfer.- 9.7 The THETA as a Practical Device.- 9.7.1 Gain Considerations.- 9.7.2 Speed Considerations.- 9.7.3 Final Comments.- References.- 10. Quantum Interference Devices.- 10.1 Background.- 10.2 Two-Port Quantum Devices.- 10.2.1 Conductance Formula.- 10.2.2 Quantum Interference Transistor.- 10.3 Multiport Quantum Devices.- 10.3.1 Conductance Formula.- 10.3.2 Quantum Reflection Transistor.- 10.3.3 Quantum Networks.- Appendix: Aharonov - Bohm Phase-shift in an Electric or Magnetic Field.- References.- Additional References.- 11. Carrier Confinement to One and Zero Degrees of Freedom.- 11.1 Experimental Methods.- 11.2 Discussion of Experimental Results.- 11.3 Conclusions.- References.- 12. Quantum Effects in Quasi-One-Dimensional MOSFETs.- 12.1 Background.- 12.2 MOSFET Length Scales.- 12.3 Special MOSFET Geometries.- 12.4 Strictly 1D Transport.- 12.4.1 Localization and Resonant Tunnelling.- 12.4.2 Hopping Transport.- 12.5 Multichannel Transport (Particle in a Box?).- 12.6 Averaged Quantum Diffusion.- 12.6.1 Weak Localization.- 12.6.2 Electron-Electron Interactions.- 12.7 Mesoscopic Quantum Diffusion (Universal Conductance Fluctuations).- 12.7.1 Universal Conductance Fluctuations at Scale Lo.- 12.7.2 Self-Averaging of Conductance Fluctuations at Larger Probe Spacings.- 12.7.3 Nonlocal Response of Conductance Fluctuations at Shorter Probe Spacings.- 12.7.4 Comprehensive Comparison Between Theory and Experiment.- 12.7.5 Internal Asymmetries of Mesoscopic Devices.- 12.8 Effect of One Scatterer.- 12.8.1 Interface Traps.- 12.8.2 Quantum Effect of One Scatterer.- 12.9 Conclusion.- References.