eBook For Group III-Nitride Semiconductor Optoelectronics 1st Edition

Preface ix

1 Introduction 1

2 Band Structure and Optical Properties of Group III-Nitride Semiconductors 3

Crystal Symmetry (Wurtzite and Cubic Phases) 3

Lattice Periodicity and Crystal Hamiltonian 4

Bloch’s Theorem and Nature of Electron States 4

Quantum Mechanical Properties Corresponding to Bloch States 5

Light–Matter Interaction in Semiconductors 7

Spontaneous and Piezoelectric Polarization 11

Phonon Spectrum 13

Scattering Mechanisms 13

Donors and Deep Acceptors 17

3 Growth and Doping of Group III-Nitride Devices 19

Major Epitaxial Growth Methods 19

In Situ and Implant Doping 31

Dislocations and Point Defects 31

Dopant-induced Defects 31

Substrates and Growth 31

Gallium Nitride Growth on Silicon Substrates 32

4 Optical Properties of Low-dimensional Structures in Group III Nitrides 39

Quantum Wells, Quantum Wires, and Quantum Dots 39

The k.p Method 43

Crystal Symmetry and Low-dimensional Structures 50

Alloy Disorder and Density Functional Theory Electronic Structure Calculation 51

Deviations from Charge Neutrality and Effect on Electronic Structure 54

Polarization Engineering Using Quaternaries and Complex Structures 55

Dislocations in Low-dimensional Structures and Carrier Dynamics 57

Disorder, Carrier Localization, and Effect on Recombination and Red Shifts 57

5 Light-emitting Diodes and Lasers 67

Blue, Green, and Ultraviolet (UV) LEDs 67

Light-emitting Diode Basic Operating Principles 71

Blue, Green, and UV Lasers 72

Blue, Green, and Device Laser Materials – Device Considerations 78

Nanowire microLEDs 80

LED Quantum Efficiencies and Laser Threshold Currents in Quantum Wires and Quantum Dots 80

Auger Recombination and Efficiency Droop in Group III-Nitride LEDs 82

Dislocations in Low-dimensional Structures and Carrier Dynamics 86

Disorder, Carrier Localization, and Effect on Recombination and Red Shifts 87

Staggered Quantum-well InGaN Laser Characteristics 87

Non-polar Plane Quantum-well InGaN LEDs and Lasers 89

Semi-polar Plane Quantum-well InGaN LEDs and Lasers 90

p-Type Ohmic Contacts and Efficiency of LEDs and Lasers 91

Vertical Cavity Surface Emitting Lasers 93

Distributed Feedback Lasers 94

Plasmonic Nanolasers 94

Indium Gallium Nitride LEDs and Lasers on Si Substrates 95

6 Inter Sub-band Devices 103

Quantum Cascade Lasers 103

Infrared Photodetectors 103

7 Photodetectors 111

Ultraviolet Photodetectors 111

Complex Dielectric Function 111

Basic Principle of Operation 113

Metal–Semiconductor–Metal (MSM) Photodetector 115

Solar-blind Group III-Nitride UV Photodetectors 118

p-i-n Photodiodes 118

Schottky Barrier Photodiodes 123

Heterogenous Photodiodes with Group III Nitrides and Transition Metal Dichalcogenides 123

Alloy Nitrides and Spectral Response 124

Photodetectors and Substrate Engineering 125

8 Photovoltaics and Energy Conversion Devices 129

Indium Gallium Nitride Material System for Solar Cells 129

Basic Solar Cell Physics – p-n Junction Solar Cells 129

Intermediate Band Solar Cells 137

Substrate Effects on InGaN Solar Cells 139

Ohmic Contact Effects in p-n and p-i-n InGaN Solar Cells 140

Plasmonically Enhanced Solar Cells 140

Solar Concentrating Photovoltaics 140

Tandem Solar Cells Using Indium Gallium Nitride 141

Semiconductor Photocatalysis Using InGaN 143

9 Quantum Photonic Properties of Nitride Semiconductor Devices 147

Non-classical Light from Group III-Nitride Heterostructures 147

Spontaneous and Piezoelectric Polarization Effects 150

Spectral Diffusion in Quantum Dots 151

Photon Linewidths 152

Optically Pumped Versus Electrically Pumped Quantum Emitters 152

Photon Detection Properties 152

10 Polaritons in Nitride Semiconductor Heterostructures 155

Strong Coupling between Excitons and Cavity Modes 155

Conditions for Strong Coupling 155

Energies of Polariton Modes 156

Characterization of Polariton Modes 156

Polaritonic Lasing versus Photonic Lasing 157

Exciton Binding Energies and Polaritonic Lasing 159

Spontaneous and Piezoelectric Polarization Effects 160

Optically Pumped versus Electrically Pumped Polariton Lasers 161

Inhomogeneous Broadening in Polaritonic Lasing 161

Polariton Lasing in Quantum Heterostructure Nanocavities 162

11 Plasmon-coupled Group III-Nitride Optoelectronic Devices 163

Coupling between Localized Surface Plasmons (LSPs) and Quantum Wells 163

LEDs and Lasers Based on LSPR Coupling 163

Biosensing Schemes Based on LSPR/QW Coupling 164

InGaN QW Substrates for Surface-enhanced Raman Scattering (SERS) Extended Hotspots 165

InGaN Nanorods Plus Metal NPs for Water Splitting Using SPR Effects 166

InGaN QDs Plus Metal NPs for Water Splitting Using SPR Effects 168

12 Photonic Integrated Circuits Using Group III-Nitride Semiconductors 169

Indium Gallium Nitride (InGaN)-based Monolithic Photonic Chips 169

Photonic Integrated Circuits with Plasmonic Components 170

Exploring Modulators Using Nitrides for Easier Integration 170

Combining Photonic and Electronic Components on the Same Chip 171

Monolithically Integrated Multi-color LED Display on a Single Chip 171

13 Conclusion 173

Index 175