Nitride Semiconductor Devices

✍ Scribed by Piprek J. (ed.)

• Publisher: Wiley-VCH
• Year: 2007
• Tongue: English
• Leaves: 522
• Category: Library

✦ Synopsis

This is the first book to be published on physical principles, mathematical models, and practical simulation of GaN-based devices. Gallium nitride and its related compounds enable the fabrication of highly efficient light-emitting diodes and lasers for a broad spectrum of wavelengths, ranging from red through yellow and green to blue and ultraviolet. Since the breakthrough demonstration of blue laser diodes by Shuji Nakamura in 1995, this field has experienced tremendous growth worldwide. Various applications can be seen in our everyday life, from green traffic lights to full-color outdoor displays to high-definition DVD players. In recent years, nitride device modeling and simulation has gained importance and advanced software tools are emerging. Similar developments occurred in the past with other semiconductors such as silicon, where computer simulation is now an integral part of device development and fabrication.This book presents a review of modern device concepts and models, written by leading researchers in the field. It is intended for scientists and device engineers who are interested in employing computer simulation for nitride device design and analysis.

✦ Table of Contents

Nitride Semiconductor Devices: Principles and Simulation......Page 4
Contents......Page 8
Preface......Page 18
List of Contributors......Page 20
Part 1 Material Properties......Page 26
1.1 A Brief History......Page 28
1.2 Unique Material Properties......Page 29
1.3 Thermal Parameters......Page 30
References......Page 35
2.1 Introduction......Page 38
2.2 Band Structure Models......Page 39
2.3 Band Parameters......Page 42
2.3.1 GaN......Page 44
2.3.2 AlN......Page 50
2.3.3 InN......Page 53
2.3.4 AlGaN......Page 55
2.3.5 InGaN......Page 57
2.3.7 AlGaInN......Page 59
2.3.8 Band Offsets......Page 60
2.4 Conclusions......Page 61
References......Page 62
3.1 Why Spontaneous Polarization in III-V Nitrides?......Page 74
3.2 Theoretical Prediction of Polarization Properties in AlN, GaN and InN......Page 76
3.3 Piezoelectric and Pyroelectric Effects in III-V Nitrides Nanostructures......Page 79
3.4 Polarization Properties in Ternary and Quaternary Alloys: Nonlinear Compositional Dependence and Order vs. Disorder Effects......Page 83
3.5 Orientational Dependence of Polarization......Page 89
References......Page 92
4.1 Introduction......Page 94
4.2 Numerical Simulation Model......Page 95
4.2.1 Scattering in the Semi-Classical Boltzmann Equation......Page 97
4.3 Analytical Models for the Transport Parameters......Page 101
4.4.1 Electron Transport Coefficients......Page 104
4.4.2 Hole Transport Coefficients......Page 106
4.5.1 Electron Transport Coefficients......Page 109
4.5.2 Hole Transport Coefficients......Page 111
4.6 InN Transport Parameters......Page 112
4.6.1 Electron Transport Coefficients......Page 113
4.6.2 Hole Transport Coefficients......Page 114
References......Page 116
5.2.1 Fundamental Relations......Page 120
5.2.2 Valence Band Ordering, Optical Selection Rules and Anisotropy......Page 122
5.3.1 InN......Page 124
5.3.2 GaN and AlN......Page 127
5.3.3 AlGaN Alloys......Page 130
5.3.4 In-rich InGaN and InAlN Alloys......Page 132
5.4 Modeling of the Dielectric Function......Page 133
5.4.1 Analytical Representation of the Dielectric Function......Page 134
5.4.2 Calculation of the Dielectric Function for Alloys......Page 136
5.4.3 Influence of Electric Fields on the Dielectric Function......Page 137
References......Page 139
6.1 Introduction......Page 142
6.2 Theoretical Model......Page 143
6.2.1 Spontaneous and Piezoelectric Polarization......Page 147
6.3 Numerical Implementation......Page 148
6.3.1 Achieving Self-consistency: The Under-Relaxation Method......Page 152
6.3.2 Predictor–Corrector Approach......Page 153
6.4 Absorption Energy in AlGaN-GaN MQWs......Page 154
6.4.1 Numerical Analysis of Periodic AlGaN-GaN MQWs......Page 155
6.4.2 Numerical Analysis of Non-periodic AlGaN-GaN MQWs and Comparison with Experimental Results......Page 163
6.5 Conclusions......Page 166
References......Page 167
7.1 Introduction......Page 170
7.2.1 Bandstructure and Wavefunctions......Page 171
7.2.2 Semiconductor Bloch Equations......Page 174
7.2.3 Semiconductor Luminescence Equations......Page 176
7.2.4 Auger Recombination Processes......Page 177
7.3 Theory–Experiment Gain Comparison......Page 179
7.4.1 General Trends......Page 181
7.4.2 Structural Dependence......Page 184
7.5 Spontaneous Emission......Page 186
7.7 Internal Field Effects......Page 189
7.8 Summary......Page 191
References......Page 192
8.1 Introduction......Page 194
8.2 Theory......Page 195
8.2.1 Non-Markovian gain model with many-body effects......Page 200
8.3 Results and Discussion......Page 202
8.4 Summary......Page 213
References......Page 214
9.1 Introduction......Page 216
9.2.1 Formulation of the Problem and Previous Developments......Page 218
9.2.2 Kinetic Equation and Scattering Rates......Page 220
9.2.3 Results for Carrier–Carrier Scattering......Page 223
9.3.1 Perturbation Theory Versus Polaron Picture......Page 225
9.3.2 Polaron States and Kinetics......Page 227
9.3.3 Results for Carrier Scattering Due to LO-phonons......Page 229
9.4 Summary and Outlook......Page 232
References......Page 233
Part 2 Devices......Page 236
10.1 Introduction......Page 238
10.2 Physics-based Simulations......Page 241
10.2.1 Basic Material Properties......Page 242
10.2.2 Polarization......Page 243
10.2.3 Surface States......Page 247
10.2.4 Electron Mobility......Page 249
10.2.5 Breakdown Voltage......Page 252
10.2.6 Energy Balance Models......Page 253
10.3 Conclusions......Page 255
References......Page 256
11.1 Introduction......Page 260
11.2.2 Rate Equations......Page 261
11.2.3 Absorption......Page 263
11.2.4 Relaxation Time......Page 264
11.2.5 Dephasing Time and Spectral Linewidth......Page 265
11.3.1 Transition Wavelength and Built-In Field......Page 267
11.3.2 Absorption Spectra......Page 268
11.4 FDTD Simulator for GaN/AlGaN ISBT Switches......Page 269
11.4.1 Model......Page 270
11.4.2 Saturation of Absorption......Page 271
11.4.3 Temporal Response......Page 273
11.4.4 Future Applications......Page 274
References......Page 276
12.1 Introduction......Page 278
12.2.1 Multiple-Quantum-Well Structure......Page 281
12.2.2 Waveguide and Contacting......Page 284
12.3.1 Conduction Band Potential and Active Layer Biasing......Page 286
12.3.2 Intersubband Transitions......Page 288
12.3.3 Optical Mode and the Plasma Effect......Page 290
12.4.1 Electroabsorption......Page 291
12.4.2 Chirp Parameter......Page 294
12.4.3 Electrical Properties......Page 295
12.4.4 Figure of Merit......Page 296
12.4.5 Absorption Saturation......Page 297
12.4.6 Thermal Properties and Current......Page 298
12.4.7 Significance of the Linewidth......Page 300
References......Page 301
13.1 Introduction......Page 304
13.2 Device Structure......Page 306
13.3 Physical Models and Parameters......Page 307
13.3.1 Band Structure......Page 308
13.3.2 Polarization Effects......Page 310
13.3.3 Carrier Transport Model......Page 312
13.3.5 Spontaneous Emission......Page 313
13.3.6 Ray Tracing......Page 315
13.4 Comparison Between Simulated and Experimental Results......Page 316
13.5.1 Optimal Aluminum Composition in p-AlGaN Electron Blocking Layer......Page 318
13.5.2 Optimal Number of Quantum Wells......Page 319
13.5.3 Lattice-matched AlInGaN Electron Blocking Layer......Page 321
13.6 Conclusion......Page 324
References......Page 325
14.1 Introduction......Page 328
14.2 Simulation Approach and Materials Properties......Page 329
14.3 Device Analysis......Page 334
14.3.1 Band Diagrams, Carrier Concentrations, and Partial Currents......Page 335
14.3.2 Internal Quantum Efficiency and Carrier Leakage......Page 337
14.3.3 Emission Spectra......Page 340
14.3.4 Polarity Effects......Page 342
14.4.1 LED with Indium-free Active Region......Page 345
14.4.2 Hybrid ZnO/AlGaN LED......Page 346
14.5 Conclusion......Page 348
References......Page 349
15.1 Introduction......Page 352
15.2 Requirements for a Conversion LED Model......Page 353
15.3 Color Metrics for Conversion LEDs......Page 355
15.4.1 Phosphor Materials......Page 357
15.4.2 Luminescence and Absorption of Phosphor Particles......Page 359
15.4.3 Scattering of Phosphor Particles......Page 360
15.4.4 Determination of Material Parameters......Page 366
15.4.5 LED Ray Tracing Model......Page 369
15.5 Simulation Examples......Page 371
15.6 Conclusions......Page 375
References......Page 376
16.1 Introduction......Page 378
16.2.1 Electrical and Optical Simulation......Page 379
16.2.2 Simulation Model for Thermal Analysis......Page 382
16.3 Simulation for Electrical Characteristics and Carrier Overflow Analysis......Page 384
16.4 Perpendicular Transverse Mode and Beam Quality Analysis......Page 391
16.5 Thermal Analysis......Page 395
References......Page 403
17.1 Introduction......Page 406
17.2 Internal Mode Coupling and the Concept of "Ghost Modes"......Page 407
17.3 Device Structure and Material Parameters......Page 409
17.4 Calculation Technique......Page 410
17.5.1 Resonant Conditions......Page 411
17.5.2 Spatial Characteristics of Laser Emission under the Resonant Internal Mode Coupling......Page 416
17.5.3 Spectral Effects of the Resonant Internal Mode Coupling......Page 419
17.5.4 Carrier-Induced Resonant Internal Mode Coupling......Page 421
17.6 Discussion and Conclusions......Page 424
References......Page 427
18.1 Introduction......Page 430
18.2 Waveguide Mode Stability......Page 431
18.3 Optical Waveguide Loss......Page 437
18.4 Mode Gain Analysis......Page 442
18.5 Conclusion......Page 445
References......Page 447
19.1 Introduction to Vertical-Cavity Lasers......Page 448
19.2 GaN-based VCSEL Structure......Page 449
19.3 Theoretical Models and Material Parameters......Page 450
19.3.1 Carrier Transport......Page 451
19.3.2 Electron Band Structure......Page 454
19.3.3 Built-In Polarization......Page 457
19.3.4 Photon Generation in the Quantum Wells......Page 459
19.3.5 Optical Mode......Page 461
19.4 Simulation Results and Device Analysis......Page 462
19.4.2 Polarization Effects......Page 463
19.4.3 Threshold Current......Page 465
19.4.4 AlGaN Doping......Page 467
References......Page 468
20.1 Introduction......Page 472
20.2 The GaN VCSEL Structure......Page 474
20.3 The Scalar Optical Approach......Page 478
20.4 The Vectorial Optical Approach......Page 479
20.5 The Self-consistent Calculation Algorithm......Page 483
20.6 Simulation Results......Page 485
20.7 Discussion and Conclusions......Page 489
References......Page 490
21.1 Introduction......Page 492
21.2 Nanowire Growth and Characterization......Page 494
21.3 Nanowire Laser Principles......Page 495
21.4 Anisotropy of Material Gain......Page 496
21.5 Guided Modes......Page 500
21.5.1 Guided Modes, Dispersions, and Mode Spacing......Page 501
21.5.2 Reflection from Facets......Page 504
21.5.3 Far-field Pattern......Page 506
21.5.4 Confinement Factors for Anisotropic Nanowires......Page 508
21.5.5 Spontaneous Emission Factors......Page 511
21.6 Modal Gain and Threshold......Page 513
21.7 Conclusion......Page 514
References......Page 515
Index......Page 518