Introduction to Semiconductor Integrated Optics

Transcription

1 Introduction to Semiconductor Integrated Optics Hans P. Zappe Artech House Boston London

2 Contents acknowledgments reface itroduction Chapter 1 Basic Electromagnetics General Relationships Maxwell's Equations Current Continuity The Wave Equation ТЕМ Waves and Polarization Solving the Wave Equation Propagation Constant Maxwell for Sinusoidal Fields Energy Poynting Vector Interference 10 Chapter 2 A Summary of Semiconductors Silicon and Gallium Arsenide Crystalline Properties Miller Indices and Atomic Planes Energy Bands Band Structure Calculations Energy Bands Electron Transitions between Bands Effective Mass Carrier Concentration Density of States Fermi-Dirac Distribution 25 xv xvii xix

3 via INTRODUCTION TO SEMICONDUCTOR INTEGRATED OPTICS Intrinsic Carrier Concentration 2.4 Doping Donors and Acceptors Fermi Level Determination Degenerate Semiconductors 2.5 Transport Drift and Diffusion Contributions to Mobility High Field Effects 2.6 The PN Junction The Depletion Approximation Debye Length The PN Junction Under Bias Reverse Bias Breakdown Junction Capacitance The P-I-N Diode 2.7 Heterojunctions and Quantum Wells Single and Double Heterostructures Quantum Wells Chapter 3 Optical Properties of Semiconductors 3.1 Refractive Index 3.2 Absorption Direct Bandgap Indirect Bandgap Band Tails Free Carrier Absorption Franz-Keldysh Effect 3.3 Recombination Radiative Transitions Direct and Indirect Transitions Nonradiative Recombination 3.4 Polarization Susceptibility Polarization Model 3.5 Complex Material Constants Complex Dielectric Constant Complex Refractive Index Complex Propagation Constant Summary of Complexities 3.6 Dielectric Tensor 3.7 Kramers-Kronig Relations

4 Contents IX Ihapter 4 Optical Semiconductor Materials III-V Materials The III-V Extended Family Regimes of Application Composition and Optical Properties Refractive Index Energy Gap Bulk Crystal Growth Liquid-Encapsulated Czochralski Horizontal Bridgman and Vertical Gradient Freeze Wafer Sawing and Flat Grinding Epitaxial Layer Growth Liquid Phase Epitaxy Molecular Beam Epitaxy Metalorganic Chemical Vapor Deposition More Optical Materials Silicon Silicon: Modifications and Accessories Silicon/Germanium Other Compound Semiconductors 96 Lapter Basics of Semiconductor Processing A Typical Optoelectronic Process The Basics The Embellishments The Environment Photolithography Masks Photoresist Lift-Off and Image Reversal Mask Aligners Nonoptical Lithography Etching Dry Etching Basics and Machinery Etch Gasses Problems and Limitations Wet Etching Dielectrics Plasma Deposition Chemical Vapor Deposition Metals Processing Varia

5 X INTRODUCTION TO SEMICONDUCTOR INTEGRATED OPTICS III-V Post-Processing Ion Implantation Rapid Thermal Annealing Chapter 6 Reflections at Boundaries 6.1 Angles of Reflection and Refraction 6.2 Boundary Conditions of Electromagnetic Fields 6.3 Reflection and Transmission Coefficients ТЕ Configuration TM Configuration Power Transmission and Reflection 6.4 Two Special Cases Normal Incidence Total Internal Reflection Chapter 7 Guided Waves and Slab Waveguides 7.1 Perfect Mirror Waveguides Discrete Waveguide Modes Propagation Constants and Effective Index 7.2 Dielectric Waveguides: the Ray Optic Model Total Internal Reflection Symmetric Waveguides Monomode Conditions Propagation Constants and Effective Index, Again Asymmetric Waveguides 7.3 Electromagnetic Model Eigenvalue Equation for a Slab Waveguide Propagating and Decaying Solutions Propagation and Decay Constants 7.4 Dielectric Waveguides: Electric and Magnetic Fields Field Solutions Power Normalization Symmetric Waveguide: Cutoff Condition Asymmetric Waveguide: Cutoff Condition Confinement Factor 7.5 Goos-Hänchen Shift Chapter 8 Optical Channel Waveguides 8.1 Two-Dimensional Waveguide Structures Etched Structures Other III-V Waveguide Techniques Silicon-Based Waveguides 8.2 Two-Dimensional Waveguide Analysis

6 Contents XI Effective Index Approximation Method of Field Shadows Waveguide Modes Monomode Waveguides Lateral Waveguiding Mechanisms Input/Output Coupling Butt Coupling End-Fire Coupling Grating Coupling Prism Couplers Waveguide Losses Band-Edge Absorption Free-Carrier Absorption Scattering Radiation Losses Typical Loss Values Loss Characterization Cut-Back Technique Fabry-Perot Resonances Passive Waveguide Structures Curves Couplers Y-Junctions 209 hapter 9 Lasers Laser Operation A Quick Heuristic Discussion Photon Emission in Semiconductors Spontaneous and Stimulated Emission Electron Distribution and Transition Rates Lineshape Function Spectral Shape and Broadening Optical Gain Amplification and Attenuation Semiconductor Gain Gain Saturation Hole Burning Laser Oscillation Fabry-Perot Etalon The Etalon with Optical Gain Laser Resonance Semiconductor Laser Structures Materials and Heterostructures 239

7 xii INTRODUCTION TO SEMICONDUCTOR INTEGRATED OPTICS Quantum-Well Lasers Typical Laser Designs Reliability and Lifetime Electrical and Optical Characterization Light- Threshold Current Output Power and Efficiency Spectrum Spatial Intensity Distribution Temperature Variations Emitting Diodes Distril >uted Feedback Lasers Distributed Feedback DBR/DFB Fabrication Operation and Special Features Surface-Emitting Lasers Mirror Deflectors Surface Grating Couplers VCSELs Chapter 10 Photodetectors 10.1 General Principles Photon to Electron Conversion Efficiency Noise 10.2 Semiconductor Detector Materials 10.3 The P-I-N Photodiode Waveguide Detector Surface Detector 10.4 Schottky and MSM Detectors Schottky Barrier MSM Detector Surface Illumination 10.5 Avalanche Photodiodes Avalanche Multiplication Photodetector Structure Chapter 11 Modulators 11.1 Phase and Intensity Modulation 11.2 Modulator Structures: a Brief Survey Electro-Optic Effects Directional Couplers Total Internal Reflection Deflectors Bragg Gratings

8 Contents xiü Surface Acoustic Wave Devices Interferometric Modulators Traveling Wave Modulators Mechanical Beam Steering Electro-Optics Pockets Effect Kerr Effect Franz-Keldysh Effect Plasma Effects Silicon Electro-Optics Quantum-Well Modulators Quantum-Confined Stark Effect Electrorefraction in Quantum Wells Chirp Quantum-Well Modulator Structures Interferometric Modulators Output Characteristics Interferometer Modulator Performance Other Origins for Phase Shift 315 hapter 12 Hybridization and Monolithic Integration Integration versus Hybridization Examples: Photonic Integration Examples: Electronics Integration Examples: Hybridization Waveguide-Based Integration Evanescent and Butt Coupling Selective Growth Quantum-Well Intermixing Electrical Isolation Monolithic Devices and Systems Odier Integratable Device Structures Monolithic System Implementations Hybrid Optical Systems Alignment Bonding Heteroepitaxy 342 ppendix A List of Variables 349 ppendix В List of Useful Physical Constants 357 bout the Author 359 idex 361