Light-Emitting Diodes (eBook)

Materials, Processes, Devices and Applications

Jinmin Li, G. Q. ZHANG (Herausgeber)

eBook Download: PDF

2019 | 1st ed. 2019
VIII, 600 Seiten
Springer International Publishing (Verlag)
978-3-319-99211-2 (ISBN)

Infos

Comprehensive in scope, this book covers the latest progresses of theories, technologies and applications of LEDs based on III-V semiconductor materials, such as basic material physics, key device issues (homoepitaxy and heteroepitaxy of the materials on different substrates, quantum efficiency and novel structures, and more), packaging, and system integration. The authors describe the latest developments of LEDs with spectra coverage from ultra-violet (UV) to the entire visible light wavelength. The major aspects of LEDs, such as material growth, chip structure, packaging, and reliability are covered, as well as emerging and novel applications beyond the general and conventional lightings. This book, written by leading authorities in the field, is indispensable reading for researchers and students working with semiconductors, optoelectronics, and optics.

•         Addresses novel LED applications such as LEDs for healthcare and wellbeing, horticulture, and animal breeding;
  
•         Editor and chapter authors are global leading experts from the scientific and industry communities, and their latest research findings and achievements are included;
  
•         Foreword by Hiroshi Amano, one of the 2014 winners of the Nobel Prize in Physics for his work on light-emitting diodes.

Professor Jinmin Li is Director of Solid State Lighting R&D at the Center of Chinese Academy of Sciences, and the Director of the State Key Laboratory for Solid State Lighting.

Inhalt

Foreword 6
Contents 7
1 GaN Substrate Material for III–V SemiconductorEpitaxy Growth 9
1.1 Introduction 9
1.1.1 Importance of GaN Substrates 10
1.1.2 Key Drivers for GaN Substrate Commercialization Success 12
1.2 The Technical Routes for GaN Substrate Materials 13
1.2.1 Native GaN Substrates 13
1.2.2 GaN Liftoff Substrate Wafers 15
1.2.3 GaN Templates 15
1.3 Major Methods for the Growth of GaN Substrate 16
1.3.1 The Liquid-Phase Growth 17
1.3.1.1 High-Pressure Nitrogen Solution Growth (HPNSG) 17
1.3.1.2 Ammonothermal Growth 18
1.3.1.3 Na-Flux Method 20
1.3.2 Gas-Phase Growth for GaN Substrates 24
1.3.2.1 Gas-Phase Transport Method 24
1.3.2.2 Hydride Vapor-Phase Epitaxy (HVPE) 25
1.4 HVPE for GaN Substrate Materials 26
1.4.1 Chemical Reaction in the Growth of GaN by Hydride Vapor-Phase Epitaxy 26
1.4.2 Hydride Gas-Phase Epitaxial Growth System 28
1.4.3 The Growth and Doping of HVPE Nitrides 29
1.4.4 The Main Difficulties of HVPE 32
1.4.5 Epitaxial Lateral Overgrowth by HVPE 33
1.4.6 Freestanding HVPE-GaN Substrate 35
1.4.6.1 Laser Liftoff Process 36
1.4.6.2 Self-Separation Methods 38
1.4.7 Current Development Trend in HVPE-GaN Substrate Materials 39
1.4.7.1 Combined GaN Crystal Growth 40
1.4.7.2 GaN Boule by HVPE Technology 42
1.4.7.3 Nonpolar GaN Substrate 44
1.4.7.4 Low-Cost HVPE-GaN Templates on Sapphire 45
1.5 Summary 45
References 46
2 SiC Single Crystal Growth and Substrate Processing 48
2.1 Introduction for SiC Single Crystal Materials 48
2.1.1 Vapor Growth Method 49
2.1.2 Solution Growth Method 51
2.1.3 High-Temperature Chemical Vapor Deposition (HTCVD) Method 52
2.2 Structure and Physical Properties of SiC 53
2.3 SiC Single Crystal Growth by PVT Method 55
2.4 The Formation and Control of Structural Defects in SiC Single Crystals 62
2.4.1 Micropipe Defects 62
2.4.2 Foreign Polytypes 69
2.4.3 Dislocations 72
2.5 Control of Electrical Characters of SiC Crystals Grown by Sublimation Growth 75
2.5.1 n-Type Doping 76
2.5.2 p-Type Doping 80
2.5.3 Semi-insulating 83
2.6 Processing of Large-Diameter SiC Wafers 89
2.6.1 Crystal Boule Slicing 91
2.6.2 Lapping 91
2.6.3 Mechanical Polishing 92
2.6.4 Chemo-mechanical Polishing 93
References 97
3 Homoepitaxy of GaN Light-Emitting Diodes 100
3.1 Bulk GaN Substrates for Light-Emitting Devices 100
3.1.1 Growth Mechanism of HVPE System 101
3.1.2 Progress in HVPE Growth of GaN Substrate 102
3.1.2.1 Dislocation Reduction and Strain Control 102
3.1.2.2 Si-Doping for n-GaN Substrate 104
3.1.2.3 Fe-Doping for High-Resistivity GaN Substrate 105
3.1.2.4 Minority Diffusion Lengths in Bulk GaN 106
3.2 Structural Characterization in Homoepitaxial GaInN/GaN Light-Emitting Diode Growth 108
3.2.1 Evaluation of Threading Dislocation Density 112
3.2.2 Electrical Characterization and Optical Characterization of Homoepitaxial InGaN/GaN Light-Emitting Diodes 116
3.3 Nonpolar and Semipolar Orientations GaN LED Grown on Bulk GaN Substrates 120
3.3.1 Problems with Conventional c-Plane LEDs and Motivation for Nonpolar and Semipolar Orientations 120
3.3.2 Crystallography and Piezoelectricity 122
3.3.3 Performance of Nonpolar and Semipolar-Oriented LEDs Using Homoepitaxial Substrates 124
3.4 Efficiency Droop and Efficiency Enhancement of Homoepitaxial InGaN/GaN Light-Emitting Diodes 125
3.5 Light Efficiency Extraction 127
3.5.1 Surface Treatment Methods 128
3.5.2 Chip Shaping Method 129
3.5.3 Photonic Crystal Method 131
References 134
4 GaN LEDs on Si Substrate 140
4.1 Epitaxy of GaN LED on Si Substrate 140
4.1.1 Overview of GaN Epitaxy on Si 140
4.1.2 Buffer Technology 142
4.1.2.1 Thin AlN Buffer on Grid-Patterned Si Substrate 142
4.1.2.2 Graded AlGaN Buffer on Bare Si Substrate 149
4.1.3 Quantum Well Strain Engineering 155
4.1.4 V-Pits of GaN LED 157
4.2 Device Processing of GaN LEDs on Si Substrate 162
4.2.1 Reflective P-Type Ohmic Contact 163
4.2.2 Complementary Contact 164
4.2.3 Film Transferring of GaN to New Substrate 165
4.2.4 Surface Roughening of N-Polar N-Type GaN 166
4.2.5 Ohmic Contact on N-Polar N-GaN 168
4.2.6 Device Passivation 169
4.3 Device Characterization of Vertical Thin Film LEDs Based on GaN/Si Technology 169
References 174
5 The AlGaInP/AlGaAs Material System and Red/Yellow LED 178
5.1 AlGaInP/AlGaAs Material System Lattice and Bandgap Energy 178
5.2 AlGaInP/AlGaAs Material Epitaxy by MOCVD 180
5.3 AlGaInP/AlGaAs LED Structure Design and Manufacture 182
5.3.1 Bragg Reflector and Textured Chip Surfaces 182
5.3.2 Transparent Substrate 186
5.3.3 Thin-Film Structure 188
5.3.4 Flip-Chip Structure 192
5.4 AlGaInP/AlGaAs Red/Yellow LED Application in Solid-State Lighting, Display, and Communication 192
5.4.1 Application in Solid-State Lighting 192
5.4.2 Application in Display 197
5.4.3 Application in Communication 198
5.5 III-Nitrides Red/Yellow LED 201
5.5.1 GaN-Based Yellow Light-Emitting Diodes 201
5.5.2 Progress on GaN-Based Yellow LED 202
5.5.3 Substrate Technique 205
References 206
6 The InGaN Material System and Blue/Green Emitters 210
6.1 Blue LEDs 210
6.1.1 Buffer Layer for the Growth of GaN and Growth of High-Quality GaN Materials 210
6.1.2 New Buffer Layer for High-Quality GaN Materials 215
6.1.3 Design and Growth of High-Efficiency Blue LEDs 218
6.1.4 Device of High-Efficiency InGaN/GaN LEDs 222
6.1.4.1 InGaN/GaN Lateral LED 222
6.1.4.2 InGaN/GaN Flip-Chip LED 224
6.1.4.3 InGaN/GaN Vertical Structure LED 226
6.1.5 Tendency of Novel LEDs Structure and Application 228
6.1.5.1 Synthesis 228
6.1.5.2 Nanowire LED 230
6.2 Green LEDs 231
6.2.1 Polarization Fields in the InGaN-Based LEDs 231
6.2.2 Internal Quantum Efficiency Promotion in the Green LEDs 233
6.2.3 Light Extraction 240
References 242
7 Al-Rich III-Nitride Materials and UltravioletLight-Emitting Diodes 251
7.1 Heteroepitaxy of AlN Material by MOVPE 251
7.1.1 Al Precursor-Related Pre-reaction Issues in AlN MOVPE 251
7.1.1.1 Reaction Mechanism (Thermodynamics and Kinetics) 252
7.1.1.2 The Initial Process of Adduct Reactions 253
7.1.1.3 The Adduct Reactions as the Functions of Temperature 254
7.1.1.4 The Surface Reaction of the Adducts 255
7.1.1.5 The Decomposition Processes of the TMAl 256
7.1.1.6 Approaches to Reduce the Parasitic Reactions 258
7.1.2 Defects and Stress Control of AlN Epitaxy on Sapphire 260
7.1.2.1 Epitaxial Lateral Overgrowth 261
7.1.2.2 Buffer-Assisted Technique 262
7.1.2.3 Interlayers 263
7.1.2.4 Special Growth Process Control 264
7.2 Structural Design for Efficient DUV LEDs 265
7.2.1 AlN and High Al Component AlGaN Epitaxy Technology 266
7.2.2 Study on N-Type Doping of AlGaN Materials 266
7.2.3 Study on P-Type Doping of AlGaN Materials 266
7.2.4 Quantum Efficiency Study of UV LED Structure 267
7.3 Homoepitaxy of DUV LEDs on AlN Substrate 268
7.3.1 Homoepitaxy on AlN Substrates 268
7.3.2 Pseudomorphic AlGaN on AlN Substrates 270
7.3.3 Pseudomorphic DUV LEDs on AlN Substrates 271
7.3.4 Light Extraction Efficiency for Pseudomorphic DUV LEDs on AlN Substrates 272
7.4 Light Exaction Issues of DUV LEDs 274
7.4.1 Al-Rich-Induced Optical Polarization Effect in DUV LEDs 274
7.4.2 Surface Patterning and High Reflective Techniques for DUV LEDs 276
7.4.2.1 Surface Patterning 276
7.4.2.2 High Reflective Techniques 278
References 278
8 Technology and Droop Study for High InternalQuantum Efficiency 286
8.1 Introduction 286
8.2 Techniques for High Internal Quantum Efficiency 287
8.3 Characterization for Internal Quantum Efficiency 300
8.4 Origins of Efficiency Droop 304
8.5 Some Remedies to Alleviate the Efficiency Droop 307
8.6 Summary 311
References 311
9 On the Light Extraction Efficiency for III-Nitride-Based Light-Emitting Diodes 316
9.1 Introduction 316
9.2 Chip Structure Engineering 317
9.3 Engineering the Optical Reflections 318
9.4 Micro-/Nanostructure Engineering 322
9.4.1 Surface Texturing 323
9.4.2 Photonic Crystal 326
9.4.3 Patterned Substrate 329
9.5 Surface Plasmon-Enhanced LEDs 333
9.6 Summary 335
References 337
10 Enhancing Wall-Plug Efficiency for Deep-UV Light-Emitting Diodes: From Crystal Growth to Devices 341
10.1 Introduction 341
10.2 UV-LED Efficiency Components 342
10.2.1 Internal Quantum Efficiency (IQE) 343
10.2.1.1 Threading Dislocations 345
10.2.1.2 Quantum-Confined Stark Effect (QCSE) 346
10.2.2 Injection Efficiency (INJ) and Wall-Plug Efficiency (WPE) 347
10.2.3 Light Extraction Efficiency (LEE) 348
10.3 Deep-UV Photon Emission from Extreme Quantum-Confined GaN/AlN Heterostructures 350
10.3.1 Motivation of Using GaN Instead of AlGaN 350
10.3.2 Evolution of Band Structure of Ultrathin AlN/GaN/AlN Heterostructures 351
10.3.3 Achievable Wavelengths and Inhomogeneous Broadening: Theory vs Experiment 353
10.4 MBE Growth of GaN/AlN Quantum Structures (Wells and Dots) for Enhanced IQE 357
10.4.1 MBE System in Brief 357
10.4.1.1 Basic MBE Structure 358
10.4.1.2 In Situ Characterization of Growth: Use of RHEED 359
10.4.1.3 MBE Growth Modes 361
10.4.1.4 MBE Growth Condition Markers 361
10.4.2 MBE Growth of GaN/AlN Quantum Heterostructures 364
10.4.2.1 Quantum Wells/Quantum Dots/Disks 364
10.4.2.2 MBE Growth Parameter Optimization 366
10.4.2.3 Single and Double Monolayer ?-GaN Quantum Wells 368
10.4.2.4 IQE Improvement with ?-GaN Quantum Disks 370
10.5 Polarization Doping-Assisted Deep-UV LEDs with GaN/AlN Quantum Structures: Enhanced Carrier Injection 378
10.5.1 Polarization-Induced Doping to Enhance Vertical Electrical Conductivity for LEDs 378
10.5.2 Structural Design of Deep-UV LEDs with Polarization-Induced Doping 380
10.5.3 Tunable Deep-UV Emission over 232–270 nm 381
10.5.4 Cryogenic Operation of a Deep-UV LED 385
10.6 Enhancement of Light Extraction with Ultrathin GaN/AlN Quantum Heterostructure Deep-UV LEDs 391
10.7 Conclusion 394
References 394
11 Reliability of Ultraviolet Light-Emitting Diodes 400
11.1 AlGaN-Based Ultraviolet Light-Emitting Diodes 400
11.2 InGaN-Based Ultraviolet Light-Emitting Diodes 415
11.3 Reliability of Packages for Ultraviolet Light-Emitting Diodes 417
11.4 Summary 423
References 423
12 Nitride Nanowires for Light Emitting Diodes 428
12.1 Introduction 428
12.2 NW Growth for LEDs 432
12.2.1 Spontaneous Growth of GaN NWs by MBE 432
12.2.1.1 Growth Conditions 432
12.2.1.2 Growth Mechanisms Involved in MBE Growth 433
12.2.1.3 Selective Area Growth of GaN NWs in MBE 435
12.2.1.4 Axial Growth of Heterostructures 436
12.2.2 MOVPE Growth of Catalyst-free Nitride NWs 437
12.2.2.1 Methods and Growth Conditions 437
12.2.2.2 Growth Mechanisms Involved in MOVPE NW Formation 440
12.2.2.3 NW Growth by Selective Area Growth in MOVPE 441
12.2.2.4 Radial Growth of Heterostructures 441
12.2.3 Comparison of Catalyst-free Growth Method of Nitride NWs 442
12.3 NW LED Fabrication 442
12.4 Early Demonstrations of Nitride NW LEDs 444
12.5 NW LEDs With Emission Color in the Visible Spectral Range 446
12.5.1 MOVPE-grown NW LEDs 447
12.5.2 MBE-grown NW LEDs 452
12.5.3 White NW LEDs 456
12.5.3.1 Phosphor Converted White LEDs 457
12.5.3.2 Phosphor-free White LEDs by RGB Color Mixing 457
12.6 Ultraviolet NW LEDs 460
12.7 Operation Speed of NW LEDs 461
12.8 NW Photonic Platforms 463
12.9 Open Issues of NW LEDs 465
12.9.1 Low IQE Values 465
12.9.2 Reabsorption in Core/Shell LEDs 466
12.9.3 Low EQE Values 467
12.9.4 Wavelength Control 467
12.9.5 Electrical Injection Inhomogeneities 469
12.9.5.1 Intra-wire Injection Inhomogeneities 469
12.9.5.2 Wire-to-wire Injection Inhomogeneities 470
12.10 Flexible NW LEDs 471
12.10.1 Motivation 472
12.10.2 Fabrication Approaches 473
12.10.2.1 Direct Growth 473
12.10.2.2 In-plane Transfer 473
12.10.2.3 Vertical Transfer 474
12.11 Summary 476
References 477
13 Light-Emitting Diodes for Healthcare and Well-being 488
13.1 Basic Theories and Mechanisms of LED Phototherapy 488
13.1.1 Basic Theories and Mechanisms of Low-Level Light Therapy 488
13.1.1.1 Development History of LED for Low-Level Light Therapy 488
13.1.1.2 Interactivity Between Light and Human Tissues 489
13.1.1.3 Light Dosiology for LED Used in Low-Level Light Therapy 490
13.1.1.4 Mechanisms of Low-Level Light Therapy 490
13.1.2 Basic Theories and Mechanisms of LED Mediated Photodynamic Therapy 493
13.1.2.1 Basic Theories of LED-Mediated Photodynamic Therapy 493
13.1.2.2 Mechanisms of LED-Mediated Photodynamic Therapy 495
13.2 Clinical Application of LED Light 497
13.2.1 LED Light in Low Level Light Therapy 497
13.2.1.1 Neonatal Jaundice 497
13.2.1.2 Emotion Cognitive Impairment 498
13.2.1.3 Wound Healing 498
13.2.1.4 Acne 499
13.2.1.5 Facial Rejuvenation 500
13.2.1.6 Scars 500
13.2.1.7 Motor Functions 501
13.2.1.8 Pains 501
13.2.2 Application of LED Light Sources in Photodynamic Therapy 502
13.2.2.1 Actinic Keratosis 502
13.2.2.2 Acne 502
13.2.2.3 Basal Cell Carcinoma 503
13.2.2.4 Oral Antibacterial Therapy 503
13.2.2.5 Bactericidal Treatment for Deep Caries 504
13.2.2.6 Periodontitis 505
13.2.2.7 Denture Stomatitis 505
13.3 LED Medical Equipment 506
13.3.1 Application of LED Equipment in Medical Field 506
13.3.1.1 Lighting 506
13.3.1.2 Disinfection and Sterilization 506
13.3.1.3 Phototherapy 506
13.3.2 LED Phototherapy Device 507
13.3.2.1 Low-Level Light Therapy (LLLT) Devices 507
13.3.2.2 LED Photodynamic Therapeutic Devices 510
References 511
14 Light-Emitting Diodes for Horticulture 515
14.1 Fundamentals and Challenges of LED Lighting Technology for Horticulture 515
14.1.1 Role of Light and Major Light Environmental Factors 516
14.1.2 Dry Mass Increase and Value-Addition of Plant by Lighting 516
14.1.3 Basic Properties of LEDs Necessary for Design and Operation of PFAL 517
14.1.4 Complexity of Light Environmental Control 519
14.1.4.1 Purpose of Environmental Control 519
14.1.4.2 Optimal PPFD as Affected by Other Environmental Factors 519
14.1.5 Challenges for Smart LED Lighting Systems 520
14.1.5.1 Starting Points 520
14.1.5.2 Basic Ideas 521
14.1.5.3 Simple Examples 521
14.1.5.4 Smart LED Lighting System 522
14.2 Case Study: LED Lighting for Lettuce Seedlings in PFAL 523
14.2.1 Plant Materials and Experiment Design 523
14.2.1.1 Plant Materials and Growth Conditions 523
14.2.1.2 Treatment and Experiment Design 525
14.2.1.3 Measurements for Lettuce Growth and Quality 525
14.2.2 Effect of Lighting Environment at Seedling Stage on Leaf Morphology and Growth of Lettuce Seedlings 526
14.2.3 Effects of PPFD and Photoperiod at Seedling Stage on Mature Lettuce Growth and Quality 529
14.2.4 Effects of PPFD, Photoperiod, and Light Quality at Seedling Stage on Mature Lettuce Growth and Quality 529
14.3 Case Study: LED Lighting for Hydroponic Lettuce in PFAL 534
14.3.1 Plant Materials and Experiment Design 534
14.3.1.1 Plant Materials and Growth Conditions 534
14.3.1.2 Treatment and Experiment Design 534
14.3.1.3 Growth Quality and Photosynthetic Measurements 535
14.3.2 LED Lighting Affects Growth of Hydroponic Lettuce 536
14.3.3 LED Lighting Affects Hydroponic Lettuce Quality 539
14.3.4 Continuous Photosynthesis and Light Responses of Hydroponic Lettuce 542
14.3.5 Energy Use Efficiency of Artificial Light for Lettuce Production 544
References 546
15 The Effect and Mechanism of Light on the Growth, Food Intake, and Gonad Development of Atlantic Salmon (Salmo salar) Reared in RAS 550
15.1 Photoperiod Regulate Gonad Development via Kisspeptin/Kissr in Hypothalamus and Saccus Vasculosus of Salmo salar 550
15.1.1 Introduction 550
15.1.2 Materials and Methods 551
15.1.3 Results 552
15.1.3.1 The Location of Skissr and sGnRH3 in the Brain of Atlantic Salmon 552
15.1.3.2 Changes in Skissr in the Hyp and SV During Gonad Development 553
15.1.3.3 Changes in sGnRH3 in the Hyp and SV During Gonadal Development 554
15.2 Photoperiod May Regulate Growth via a Leptin Receptor in the Hypothalamus and Saccus Vasculosus of Salmo salar 555
15.2.1 Introduction 555
15.2.2 Materials and Methods 557
15.2.3 Results 558
15.2.3.1 Location of AsMR and AsLR in the Brain of Atlantic Salmon 558
15.2.3.2 Expression Pattern of AsMR in the Different Photoperiod in the Hypothalamus of Atlantic Salmon 559
15.2.3.3 Expression Pattern of AsLR in Different Photoperiods in the Hypothalamus and SV of Atlantic Salmon 561
15.3 The Effect and Mechanism of Light on the Growth, Food Intake, and Energy Budget of Abalone (Haliotis discus hannai Ino) 562
15.3.1 Introduction 564
15.3.2 Materials and Methods 564
15.3.3 Results 568
15.3.3.1 Specific Growth Rate 568
15.3.3.2 Biochemical Composition 569
15.3.3.3 Determination of Energy Parameters 569
15.4 Effects of Light Quality and Photoperiod on the Growth and Energy Metabolism of H. discus hannai 572
15.4.1 Introduction 572
15.4.2 Materials and Methods 573
15.4.3 Results 576
15.4.3.1 Food Conversion Efficiency 576
15.4.3.2 Digestive Enzyme Activity 577
15.4.3.3 Antioxidant Enzyme Activity 577
References 581
Index 584

Produkt-Details

• Erscheint lt. Verlag: 7.1.2019
• Reihe/Serie: Solid State Lighting Technology and Application Series
• Reihe/Serie: Solid State Lighting Technology and Application Series
• Zusatzinfo: VIII, 600 p. 362 illus., 256 illus. in color.
• Verlagsort: Cham
• Sprache: englisch
• Themenwelt: Technik ► Elektrotechnik / Energietechnik
• Themenwelt: Technik ► Maschinenbau
• Schlagworte: Beyond illumination • Droop study • Entire visible lighting • Epitaxy growth • High internal quantum efficiency • Homoepitaxy and heteroepitaxy • III-V semiconductor materials • Light Extraction Efficiency • More than illumination • Optoelectronics and optics • Ultra-violet lighting
• ISBN-10: 3-319-99211-2 / 3319992112
• ISBN-13: 978-3-319-99211-2 / 9783319992112