Nanowires (eBook)

Preface 6
Contents 9
1 Emergence of Nanowires 14
Abstract 14
1.1 Introduction: Motivation for Nanowires 14
1.1.1 Importance of One-Dimensional Materials 15
1.1.2 Synthetic Challenges and Initial Design 17
1.1.3 Top-Down and Bottom-Up Nanotechnology 18
1.2 Micron-Scale Whiskers: VLS Concept 19
1.2.1 Concept and Key Results 19
1.2.2 Limitations 21
1.3 Other Early Works 21
1.3.1 Top-Down Lithography-Based Si Nanopillars 21
1.3.2 Carbide Nanorods 22
1.3.3 Nanowiskers by Vapor Phase Epitaxy 22
1.4 Beginning of Rapid Growth: Vapor-Phase Nanocluster Catalyzed Growth 23
References 24
2 General Synthetic Methods 27
Abstract 27
2.1 Introduction 27
2.2 Vapor Phase Growth 28
2.2.1 Laser-Assisted Catalytic Growth 28
2.2.2 Chemical Vapor Deposition 30
2.2.3 Chemical Vapor Transport 32
2.2.4 Molecular Beam Epitaxy 33
2.2.5 Vapor-Solid-Solid Growth 34
2.2.6 Vapor-Solid Growth 34
2.2.7 Oxide-Assisted Growth 35
2.3 Templated Growth 36
2.3.1 Formation Inside Nanopores 36
2.3.2 Templating Against Self-assembled Structures 37
2.3.3 Construction on Existing Nanostructures 37
2.3.4 Superlattice Nanowire Pattern Transfer 38
2.4 Solution-Based Methods 39
2.4.1 Solution-Liquid-Solid Growth 39
2.4.2 Supercritical Fluid-Liquid-Solid Growth 40
2.4.3 Solvothermal/Hydrothermal Synthesis 41
2.4.4 Directed Solution Phase Growth 42
2.5 Future Directions and Challenges 43
References 44
3 Structure-Controlled Synthesis 50
Abstract 50
3.1 Introduction 50
3.2 Homogeneous Nanowires 51
3.3 Axial Modulated Structures 53
3.3.1 Early Work 53
3.3.2 Semiconductor Heterojunctions 54
3.3.3 Metal-Semiconductor Heterostructures 54
3.3.4 p-n Homojunctions 56
3.3.5 Ultrashort Morphology Features 59
3.4 Radial/Coaxial Modulated Structures 59
3.4.1 Semiconductor Radial Structures 60
3.4.2 Coaxial Modulated Structures 63
3.5 Branched/Tree-Like Structures 64
3.5.1 Sequential Catalyst-Assisted Growth 65
3.5.2 Solution Growth on Existing Nanowires 67
3.5.3 Phase Transition Induced Branching 67
3.5.4 One-Step Self-catalytic Growth 69
3.5.5 Screw Dislocation Driven Growth 69
3.6 Kinked Structures 71
3.6.1 Undersaturation/Supersaturation-Induced Kinking 71
3.6.2 Confinement-Guided Kinking 73
3.7 Future Directions and Challenges 74
References 75
4 Hierarchical Organization in Two and Three Dimensions 79
Abstract 79
4.1 Introduction 79
4.2 Post-growth Assembly 80
4.2.1 Fluidic Method 80
4.2.2 Langmuir-Blodgett Method 82
4.2.3 Blown Bubble Method 87
4.2.4 Chemical Interactions for Assembly 88
4.2.5 Assembly at Interfaces 89
4.2.6 Electric/Magnetic Field-Based Methods 91
4.2.6.1 Assembly Using Dielectrophoresis Or Electric Fields 91
4.2.6.2 Assembly Using Magnetic Fields 92
4.2.7 PDMS Transfer Method 92
4.2.8 Printing 95
4.2.9 Nanocombing-Based Assembly 97
4.2.10 Other Assembly Methods 99
4.2.10.1 Knocking-Down 99
4.2.10.2 Strain-Release 99
4.2.10.3 Assemblies Induced By External Nanostructures 99
4.3 Patterned Growth 100
4.3.1 Epitaxial Growth from Patterned Nanocluster Catalysts 100
4.3.1.1 Photolithography Or Electron-Beam Lithography 100
4.3.1.2 Nanosphere Lithography 101
4.3.1.3 Gold Deposition Masks Based on Porous Alumina 104
4.3.1.4 Nanoimprint Lithography 104
4.3.2 Substrate-Step-Directed Growth 105
4.4 Future Directions and Challenges 107
5 Nanoelectronics, Circuits and Nanoprocessors 113
Abstract 113
5.1 Introduction and Historical Perspective 113
5.2 Basic Nanoelectronic Devices 114
5.2.1 Field-Effect Transistors 114
5.2.1.1 Homogeneous Nanowire-Based Devices 115
5.2.1.2 Axial Heterostructures 117
5.2.1.3 Radial Heterostructures 118
5.2.1.4 Crossed Nanowire Structures 121
5.2.1.5 Junctionless Nanowire Transistors 121
5.2.2 p-n Diodes 122
5.2.2.1 Crossed-wire p-n Junctions 123
5.2.2.2 Axial Nanowire p-n Diodes 123
5.3 Simple Circuits 125
5.3.1 Logic Gates 125
5.3.2 Ring Oscillators 130
5.3.3 Demultiplexers 131
5.3.4 Nonvolatile Memory 132
5.3.4.1 Resistive Memory 135
5.3.4.2 Flash Memory 136
5.3.4.3 Ferroelectric Memory 137
5.3.4.4 Phase-Change Memory 137
5.4 Nanoprocessors 139
5.4.1 Logic Tiles 139
5.4.2 Arithmetic Logic 141
5.4.3 Sequential Logic 142
5.4.4 Basic Nanocomputer 143
5.5 Future Directions and Challenges 146
References 147
6 Nanophotonics 153
Abstract 153
6.1 Introduction 153
6.2 Optical Phenomena 154
6.2.1 Photoluminescence from Nanowire Structures 154
6.2.1.1 Homogeneous Nanowires 154
6.2.1.2 Axial Heterostructures 155
6.2.1.3 Radial Heterostructures 156
6.2.2 Nonlinear Processes 156
6.2.2.1 Second Harmonic Generation 158
6.2.2.2 Third-Harmonic Generation and Four-Wave Mixing 160
6.2.2.3 Stimulated Raman Scattering 160
6.3 Photonic Devices 162
6.3.1 Nanowire Waveguides 162
6.3.2 Nanoscale Light-Emitting Diodes 163
6.3.2.1 Crossed Nanowire Structures 163
6.3.2.2 Axial Heterostructures 165
6.3.2.3 Radial Heterostructures 165
6.3.3 Optically-Pumped Nanowire Lasers 166
6.3.3.1 Principles of Optically-Pumped Nanowire Lasers 167
6.3.3.2 UV Lasers 167
6.3.3.3 Visible Lasers 169
6.3.3.4 Near-IR Lasers 170
6.3.3.5 Wavelength-Tunable Lasers 172
6.3.3.6 Single-Mode Lasers 174
6.3.4 Electrically-Pumped Nanowire Lasers 176
6.3.5 Photodetectors 177
6.3.5.1 Photodiodes 177
6.3.5.2 Phototransistors 178
6.3.5.3 Superconductor Nanowire Photodetectors 178
6.4 Future Directions and Challenges 178
References 179
7 Quantum Devices 186
Abstract 186
7.1 Introduction 186
7.2 Quantum Dot Systems in Semiconductor Nanowires 188
7.2.1 Configurations of Quantum Dot Systems in Nanowires 188
7.2.2 Basic Electronic Properties of Quantum Dots 190
7.2.3 Single Quantum Dots in Nanowires 191
7.2.4 Coupled Quantum Dots in Nanowires 193
7.2.5 g-Factor and Spin-Orbit Interaction 196
7.3 Hybrid Superconductor-Semiconductor Devices 201
7.3.1 Josephson Junctions 201
7.3.2 Majorana Fermions 203
7.4 Topological Insulators 205
7.5 Future Directions and Challenges 206
References 207
8 Nanowire-Enabled Energy Storage 211
Abstract 211
8.1 Introduction 211
8.2 Lithium–Ion Batteries 212
8.2.1 Anodes 213
8.2.1.1 Si 213
8.2.1.2 Metal Oxides 216
8.2.2 Cathodes 219
8.3 Electrochemical Capacitors 222
8.4 Sodium-Ion Batteries 227
8.5 Future Directions and Challenges 227
References 228
9 Nanowire-Enabled Energy Conversion 234
Abstract 234
9.1 Introduction 234
9.2 Photovoltaics 235
9.2.1 Nanowire Arrays for Enhanced Light Absorption 236
9.2.2 Radial Junction Nanowires for Enhanced Carrier Separation 240
9.2.3 Tuning Band Gaps of III–V Compounds 243
9.3 Photoelectrochemical Conversion/Photocatalysis 245
9.3.1 Si Nanowire-Based Photoelectrochemical Water Splitting 246
9.3.2 Dual-Band Gap Artificial Photosynthesis 247
9.4 Thermoelectrics 251
9.5 Piezoelectric Effects 253
9.6 Future Directions and Challenges 255
References 255
10 Nanowire Field-Effect Transistor Sensors 262
Abstract 262
10.1 Introduction 262
10.2 Fundamental Principles of Field-Effect Transistor Sensors 263
10.3 Examples of Nanoelectronic Sensors 265
10.3.1 Protein Detection 265
10.3.2 Nucleic Acid Detection 267
10.3.3 Virus Detection 268
10.3.4 Small Molecule Detection 269
10.4 Methods for Enhancing the Sensitivity of Nanowire Sensors 270
10.4.1 3D Branched Nanowires for Enhanced Analyte Capture Efficiency 270
10.4.2 Detection in the Subthreshold Regime 270
10.4.3 Reducing the Debye Screening Effect 272
10.4.4 Electrokinetic Enhancement 274
10.4.5 Frequency Domain Measurement 274
10.4.6 Nanowire–Nanopore Sensors 276
10.4.7 Double-Gate Nanowire Sensors 277
10.4.8 Detection of Biomolecules in Physiological Fluids 277
10.5 Future Directions and Challenges 278
References 279
11 Nanowire Interfaces to Cells and Tissue 283
Abstract 283
11.1 Introduction 283
11.2 Nanowire/Cell Interfaces and Electrophysiological Recording 284
11.2.1 Traditional Extracellular Electrophysiological Recording 284
11.2.1.1 Principles of Extracellular Recording 284
11.2.1.2 Passive Metallic Microelectrodes and Their Scaling Limits 285
11.2.1.3 Active Transistor Electrodes 285
11.2.1.4 Extracellular Electrode/Cell Interfaces 285
11.2.2 Nanowire Transistors for Extracellular Recording 286
11.2.2.1 Extracellular Recording from Cultured Neurons 286
11.2.2.2 Extracellular Recording from Cardiac Cells 286
11.2.2.3 Extracellular Recording from Other Electrogenic Cells 290
11.2.3 Intracellular and Intracellular-like Electrophysiological Recording 290
11.2.3.1 Strengths and Constraints of Intracellular Measurements 290
11.2.3.2 Intracellular-Like Recording with Protruding Metal Electrodes 291
11.2.3.3 Intracellular 3D Nanowire Transistors 293
11.2.3.4 Intracellular MEA-Based Nanopillars 295
11.3 Nanowire-Tissue Interfaces and Electrophysiological Recording 296
11.3.1 Acute Brain Slice Studies with Nanowire Transistors 297
11.3.2 Cardiac Tissue Studies with Nanowire Transistors 297
11.3.3 3D Nano–Bioelectronic Hybrids 299
11.3.4 Injectable Electronics 304
11.4 Future Directions and Challenges 306
References 307
12 Conclusions and Outlook 313
Abstract 313
References 315
Curriculum Vitae 317
Index 320