Preface xiii
1 Semiconductor Physics 1
1.1 Introduction 1
1.2 Properties of Semiconductors 2
1.2.1 Atomic Bonding of Semiconductors 2
1.2.2 External Modulation Effects 3
1.3 Crystal Structure and Types of Semiconductors 6
1.3.1 Lattice and Crystal Systems 6
1.3.2 Reciprocal Lattice and Miller Indices 9
1.3.3 Common Semiconductor Crystal Structures 11
1.4 Carrier Transport 14
1.4.1 Carrier Drift and Diffusion 14
1.4.2 Quasi-Fermi Levels and Electrochemical Potentials 18
1.4.3 Carrier Generation and Recombination 19
1.5 Doping Process 22
1.5.1 Point Defects and Energy Levels 22
1.5.2 Doping Techniques 25
1.5.2.1 Thermal Diffusion 25
1.5.2.2 Ion Implantation 29
1.6 Energy Band Theory 31
1.6.1 Quantum Mechanical Equation and Bloch Wavefunction 31
1.6.2 Band Structures and Carrier Transport 34
1.7 PN Junctions 37
1.7.1 Depletion Region and Built-in Potential 38
1.7.2 Current-Voltage Characteristics 40
1.7.3 Breakdown Mechanisms in PN Junctions 44
References 45
2 Synthesis and Characterization of Optoelectronic Materials 47
2.1 Introduction 47
2.2 Synthesis of Semiconductors 48
2.2.1 Chemical Method 48
2.2.1.1 Solid/Liquid Phase Chemical Synthesis 48
2.2.1.2 Vapor Phase Chemical Synthesis 51
2.2.2 Physical Method 53
2.2.2.1 Melt Growth Techniques 54
2.2.2.2 Vapor Phase Physical Deposition 55
2.2.3 Epitaxy Growth 57
2.3 Characterization 60
2.3.1 Characterization of Electrical Properties 60
2.3.1.1 Four Probe Measurement 60
2.3.1.2 Hall Effect Measurement 64
2.3.1.3 C¢"V and I¢"V Measurements 67
2.3.2 Characterization of Optical Properties 70
2.3.2.1 Photoluminescence Spectrum 70
2.3.2.2 Ultraviolet¢"Visible Absorption Spectrum 74
2.3.2.3 Fourier Transform Infrared Spectrum 76
2.3.2.4 X-Ray Photoelectron Energy Spectrum 78
References 81
3 EUV Lithography Process of Semiconductor Devices 83
3.1 Introduction 83
3.2 EUV Lithography System and Working Principles 85
3.2.1 EUV Light Source and Exposure System 85
3.2.2 EUV Lithography Equipment 86
3.3 Development of Resist for EUV Lithography 88
3.3.1 Polymer-Based Chemically Amplified Resist 88
3.3.2 Molecular Glass Resist 89
3.3.3 Metal-Based Nanoparticles Resist 91
3.4 Mask Materials and Designs for EUV Lithography 94
3.4.1 EUV Mask Fabrication Process 95
3.4.2 Mask Substrate 96
3.4.3 ml Mirror Layer 97
3.4.4 Absorber Layer 99
3.5 Conclusions and Perspectives 101
References 103
4 Transistors 107
4.1 Introduction 107
4.2 Bipolar Transistors 107
4.2.1 Introduction 107
4.2.2 Device Structures and Working Principles 108
4.2.3 Biasing Modes and Circuit Configurations 111
4.2.3.1 Biasing Modes 111
4.2.3.2 Circuit Configurations 111
4.2.4 NPN and PNP BJTs 113
4.2.5 Heterojunction Bipolar Transistors 117
4.3 Field-Effect Transistors 119
4.3.1 Metal¢"Oxide¢"Semiconductor FETs 120
4.3.1.1 Enhancement-Mode Operation 123
4.3.1.2 Depletion-Mode Operation 123
4.3.2 Junction FETs 126
4.3.3 Metal¢"Semiconductor FETs 131
4.3.4 Modulation-Doped FETs 137
4.4 Thin-Film Transistors 142
4.4.1 Introduction 142
4.4.2 Device Structures and Characterizations 142
4.4.2.1 Current On/Off Ratio (I ON /I OFF) 145
4.4.2.2 Turn-On Voltage (V ON) 145
4.4.2.3 Threshold Voltage (V TH) 145
4.4.2.4 Subthreshold Swing (SS) 145
4.4.2.5 Mobility (¼) 146
4.4.3 Representative Materials and Devices 147
4.4.4 Emerging Applications 148
4.4.4.1 Flexible and Wearable Electronics 148
4.4.4.2 Biosensors and Biomedical Applications 149
4.4.4.3 Active-Matrix Displays and Transparent Electronics 149
4.4.4.4 Internet of Things (IoT) 149
4.4.4.5 Neuromorphic and Brain-Inspired Computing 149
4.4.4.6 Stretchable and Implantable Electronics 150
References 150
5 Luminescent Materials and Devices 151
5.1 Introduction 151
5.2 Principle of Semiconductor Luminescence 151
5.2.1 Radiative Recombination of Nonequilibrium Carriers 151
5.2.1.1 Band-to-Band Recombination 152
5.2.1.2 Band-to-Local-Energy-Level Recombination 153
5.2.1.3 Donor¢"Acceptor Pair Recombination 154
5.2.1.4 Exciton Recombination 155
5.2.1.5 Isoelectronic Center Recombination 156
5.2.2 Nonradiative Recombination Process 157
5.2.2.1 Multi-phonon Process 157
5.2.2.2 Auger Recombination 157
5.2.3 Luminescent Semiconductors 158
5.2.3.1 III¢"V Group Semiconductors 158
5.2.3.2 II¢"VI Group Semiconductors 160
5.2.3.3 Silicon Carbide (SiC) 162
5.2.3.4 Organic Materials 162
5.2.3.5 Phosphors 162
5.2.3.6 Metal Halides 162
5.3 Structure and Feature of LEDs 164
5.3.1 Principle and Structure of LEDs 164
5.3.1.1 Homojunction LEDs 164
5.3.1.2 Double-Heterojunction LEDs 165
5.3.2 Optical Properties of LEDs 167
5.3.2.1 Efficiency of LEDs 167
5.3.2.2 Luminescent Spectra 167
5.3.2.3 Distribution of Emission Intensity 168
5.3.2.4 Light-Extraction Efficiency 168
5.3.2.5 Luminous Flux and Radiant Flux 170
5.3.2.6 Luminous Intensity, Luminance, and Illuminance 170
5.3.2.7 Temperature Effect 170
5.4 Process of LEDs 171
5.4.1 Growth of Emitting Materials in LEDs 171
5.4.1.1 Growth Model of Emitting Materials in LEDs 171
5.4.1.2 Growth of Emitting Layers 172
5.4.2 Manufacture of LED Chips 175
5.5 GaN LEDs 180
5.5.1 Structure and Basic Properties of Nitrides 180
5.5.2 Blue GaN LED 181
5.5.3 Green and UV GaN LED 183
5.6 Perovskite LEDs 186
5.6.1 Structure and Progress of Perovskite LEDs 186
5.6.2 Efficiency Enhancement of Perovskite LEDs 187
5.6.2.1 Modulation of Carrier Dynamics 187
5.6.2.2 Interfacial Engineering 188
5.7 White LEDs 190
5.7.1 GaN-Based White LEDs 190
5.7.2 Perovskite-Based White LEDs 191
References 193
6 Superluminescent Light-Emitting Diodes 195
6.1 Introduction 195
6.2 History of SLED 196
6.3 Principle of Active-MMI SLED 200
6.3.1 Self-Imaging Consideration 200
6.3.2 Wide-Spectrum Consideration 201
6.4 Merit and Results of Active-MMI SLED 202
6.4.1 High-Power and Low Wall-Plug Consumption 205
6.4.2 Spectrum and Ripple Analysis 207
6.4.3 Field Patterns and Fiber-Coupling Efficiency 208
References 213
7 Solar Cells 215
7.1 Introduction 215
7.1.1 Overview of Chapter 215
7.1.2 Definition of Solar Cells 215
7.1.3 Importance of Solar Cells in Renewable Energy 216
7.2 Basic Principles of Solar Cells 217
7.2.1 Solar Spectrum and Irradiance 217
7.2.2 Photovoltaic Effect 220
7.2.3 Solar Cell Structure 221
7.2.4 Parameters of Solar Cells 223
7.3 Typical Solar Cells 225
7.3.1 Si Solar Cell 225
7.3.2 CuInGaSe Solar Cell 227
7.3.3 CdTe Solar Cell 228
7.3.4 Organic Solar Cells 230
7.3.5 Perovskite Solar Cell 231
7.3.5.1 Crystal Structure of Perovskite Materials 231
7.3.5.2 Device Structure of Perovskite Solar Cells 232
7.3.5.3 Carrier Transport in Perovskite Solar Cells 233
7.3.5.4 Primary Characterization Instrument 234
7.4 Manufacturing of Solar Cells 236
7.4.1 Si Solar Cell 236
7.4.1.1 Atomic and Band Structures of Crystalline Silicon 236
7.4.1.2 Properties of Crystalline Silicon 238
7.4.1.3 Synthesis Method of Crystalline Silicon 239
7.4.2 Perovskite Solar Cells 239
7.4.2.1 One-Step Method 239
7.4.2.2 Two-Step Method 240
7.4.2.3 Vapor-Deposition Method 241
7.4.2.4 Vapor-Assisted Solution Method 241
7.5 Applications of Solar Cells 242
7.6 Conclusion 244
References 246
8 Photodetectors 249
8.1 Introduction 249
8.2 Principle of Photodetectors 251
8.2.1 Photoconductive Type 251
8.2.1.1 Photoconduction Effect 251
8.2.1.2 Theory of Photoresistor 252
8.2.1.3 Current¢"Voltage Characteristics 257
8.2.1.4 Photoelectric Characteristics 257
8.2.1.5 Sensitivity and Gain 258
8.2.1.6 Prehistory Effect 260
8.2.2 Photodiode Type 261
8.2.2.1 PN Junction Photodiode 261
8.2.2.2 Schottky Barrier Photodiode 261
8.2.2.3 Metal¢"Insulator¢"Semiconductor Photodiode 262
8.2.2.4 Avalanche Photodiode 262
8.2.2.5 PIN Photodiode 263
8.2.3 Photovoltaic Type 263
8.2.4 Photomultiplier Tube Type 264
8.3 General Metrics of Photodetectors 265
8.3.1 Dark Current 265
8.3.2 Responsivity 266
8.3.3 Detectivity 266
8.3.4 Quantum Efficiency 267
8.3.5 Spectral Range 267
8.3.6 Response Time 267
8.3.7 Noise 268
8.4 Perovskite Photodetectors 269
8.4.1 Infrared Detectors 271
8.4.2 Visible-Light Detectors 272
8.4.3 Ultraviolet-Light Detectors 272
8.4.4 X-Ray Detectors 273
8.4.4.1 Direct-Type X-Ray Detectors 274
8.4.4.2 Indirect X-Ray Detection 278
8.4.5 Gamma-Ray Detectors 279
8.5 Metal¢"Semiconductor¢"Metal Photodetectors 280
8.5.1 Introduction 280
8.5.2 Design Considerations 282
8.5.3 Advancements and Applications 282
8.6 Organic Photomultiplication Detectors 283
8.6.1 Introduction 283
8.6.2 Design Considerations 283
8.6.3 Advancements and Applications 284
References 285
9 Graphene and Graphene-Based Devices 287
9.1 Introduction 287
9.2 Structure and Properties of Graphene 287
9.2.1 Crystal Structure of Graphene 287
9.2.2 Extraordinary Properties of Graphene 289
9.2.2.1 Electronic Properties 289
9.2.2.2 Optical Properties 291
9.2.2.3 Mechanical Properties 291
9.2.2.4 Thermal Properties 292
9.2.2.5 Chemical and Biological Properties 293
9.3 Preparation Methods of Graphene 294
9.3.1 Mechanical Exfoliation 294
9.3.2 Electrochemical Exfoliation 296
9.3.3 Direct Sonication Synthesis 297
9.3.4 Epitaxial Growth 297
9.3.5 CVD Growth 298
9.3.6 Others 299
9.4 Graphene-Based Devices 300
9.4.1 FET Devices 301
9.4.1.1 Electronic Transport Mechanism 301
9.4.1.2 Device Structure of Graphene FETs 302
9.4.1.3 Graphene Nanoribbon FETs 304
9.4.1.4 Application of Graphene FETs 305
9.4.2 Type I Two-Terminal Devices 314
9.4.3 Type II Two-Terminal Devices 316
9.4.4 Graphene Nanoelectromechanical Systems 321
9.5 Future of Graphene-Based Devices 324
References 325
Index 329
