TU-Da
Transcrição
TU-Da
Kenneth A. Jackson Kinetic Processes Crystal Growth, Diffusion, and Phase Transitions in Materials WILEYVCH WILEY-VCH Verlag GmbH & Co. KGaA Contents Preface XIII 1 Introduction 1.1 1.2 1.3 1.4 1.5 Arrhenius Plot 1 The Relationship between Kinetics and Thermodynamics The Boltzmann Distribution 4 Kinetic Theory of Gases 6 Collisions 7 1 2 Diffusion in Fluids 2.1 2.2 2.2.1 2.2.2 2.2.3 Diffusion in a Gas 11 Diffusion in Liquids 12 Diffusion Distances 13 Molecular Dynamics Simulations of Diffusion in Liquids Measurement of Diffusion Coefficients in Liquids 16 2 11 3 Diffusion in Amorphous Materials 3.1 3.2 3.2.1 3.2.2 3.3 3.4 3.5 3.6 3.7 Amorphous Materials 19 Network Glass Formers 20 Silica 20 Silicon and Germanium 20 The Glass Transition 22 The Free-Volume Model 23 Fictive Temperature 23 Diffusion in Polymers 24 The Stokes-Einstein Relationship 4 Diffusion in Crystals 4.1 4.2 4.2.1 4.2.2 Diffusion in a Crystal 27 Diffusion Mechanisms in Crystals Vacancy Diffusion 28 Interstitial Diffusion 30 19 25 27 28 13 VI Contents 4.4 4.4.1 4.4.2 4.5 4.6 4.7 4.8 4.9 4.10 4.11 A.12 4.13 Equilibrium Concentration of Vacancies 30 Thermodynamic Analysis 30 Kinetic Analysis 32 Simmons and Balluffi Experiment 34 Ionic and Covalent Crystals 34 Stoichiometry 36 Measurement of Diffusion Coefficients 36 Surface Diffusion 37 Diffusion in Grain Boundaries 38 Kirkendall Effect 38 Whisker Growth 39 Electromigration 40 5 Diffusion in Semiconductors 5.1 5.2.1 5.2.2 5.2.3 5.2.4 5.3 5.4 5.5 5.6 5.7 Introduction 45 Vacancy Diffusion in Silicon 47 Diffusion of Phosphorus in Silicon 49 Diffusion of Arsenic in Silicon 50 Diffusion of Boron in Silicon 50 Diffusion of Zinc in GaAs 51 Recombination-enhanced Diffusion 52 Doping of Semiconductors 53 Point-Defect Generation in Silicon during Crystal Growth 53 Migration of Interstitials (and Liquid Droplets) in a Temperature Gradient 56 Oxygen in Silicon 57 Gettering 57 Solid-State Doping 58 5.8 5.9 5.10 45 6 Ion Implantation 6.1 6.2 6.3 6.4 6.5 6.6 Introduction 61 Ion Interactions 62 Implantation Damage 64 Rutherford Baekscattering 67 Channeling 69 Silicon-on-Insulator 71 61 7 Mathematics of Diffusion 7.1 7.2 7.3 7.3.1 7.3.2 7.3.3 7.3.4 Random Walk 75 The Diffusion Equation 77 Solutions to the Diffusion Equation 79 Gaussian Concentration Distribution 79 Error Function Concentration Distribution 82 p/n Junction Depth 84 Separation of Variables 85 75 Contents VII 7.4 7.A.I 7.4.2 7.4.3 7.4.4 7.5 Numerical Methods 90 Finite Difference Method for Diffusion 91 Initial Surface Concentration Boundary Conditions Implanted Concentration Profile 92 Zero Flux Boundary Condition 93 Boltzmann-Matano Analysis 93 8 Stefan Problems 8.1 8.2 8.3 8.4 Steady-State Solutions to the Diffusion Equation 97 Deal-Grove Analysis 100 Diffusion-Controlled Growth of a Spherical Precipitate 102 Diffusion-Limited Growth in Cylindrical Coordinates 105 9 Phase Transformations 9.1 9.2 9.3 9.4 9.5 Transformation-Rate-Limited Growth Diffusion-Limited Growth 111 Thermally Limited Growth 111 Casting of Metals 113 Operating Point 114 10 Crystal Growth Methods 10.1 10.1.1 10.1.2 10.1.3 10.1.4 10.1.5 10.2 10.2.1 10.2.2 10.2.3 10.3 10.4 Melt Growth 117 Czochralski Growth 117 Floating Zone 121 Bridgman Method 123 Chalmers Method 123 Horizontal Gradient Freeze 124 Solution Growth 124 Growth from Aqueous Solutions 125 Flux Growth 125 Hydrothermal Growth 125 Vapor-Phase Growth 126 Stoichiometry 126 11 Segregation 11.1 11.2 11.3 11.4 11.5 11.5.1 11.5.2 11.6 11.7 Segregation during a Phase Change 129 Lever Rule 130 Scheil Equation 131 Zone Refining 133 Diffusion at a Moving Interface 134 Steady-state Diffusion at a Moving Interface Initial and Final Transients 137 Segregation in Three Dimensions 139 Burton, Primm and Schlicter Analysis 139 91 97 109 109 117 129 134 VIII Contents 12 Interface Instabilities 12.1 12.2 12.3 Constitutional Supercooling 143 Mullins and Sekerka Linear Instability Analysis Anisotropic Interface Kinetics 152 143 13 Chemical Reaction Rate Theory 13.1 13.2 13.3 13.4 13.5 13.6 13.7 13.8 The Equilibrium Constant 155 Reaction Rate Theory 155 Reaction Rate Constant 157 Transition State Theory 157 Experimental Determination of the Order of a Reaction 158 Net Rate of Reaction 160 Catalysis 162 Quasi-Equilibrium Model for the Rate of a First-Order phase Change 14 Phase Equilibria 14.1 14.2 14.3 First-Order Phase Changes 165 Second-Order Phase Changes 169 Critical Point between Liquid and Vapor 149 155 165 172 15 Nucleation 15.1 15.1.1 15.1.2 15.1.3 15.1.4 15.1.5 15.1.6 15.1.7 15.1.8 15.2 15.2.1 15.2.2 15.2.3 15.2.4 15.2.5 15.2.6 15.2.7 15.2.8 15.3 15.3.1 15.3.2 Homogeneous Nucleation 175 Volmer Analysis 176 Turnbull's Droplet Experiment 179 Surface Free Energy 181 Becker-Doring Analysis 183 Nucleation Rate 187 Limitations of the Becker-Doring Analysis 188 Assumptions in the Classical Nucleation Theory 188 Nucleation of a Precipitate Particle 189 Heterogeneous Nucleation 190 Heterogeneous Nucleation Theory 191 Nucleation Lore 192 Cavitation 193 Re-entrant Cavities 194 Cloud Seeding 195 Industrial Crystallization 195 Grain Refiners 196 Residues 196 Johnson-Mehl-Avrami Equation 197 Johnson-Mehl Equation 197 Johnson-Mehl-Avrami 199 175 16 Surface Layers 203 16.1.1 16.1.2 Langmuir Adsorption 203 CVD Growth by a Surface-Decomposition Reaction 204 163 Contents 16.1.3 16.2 16.2.1 16.2.2 16.2.3 16.3 16.3.1 16.3.2 16.4 16.5 16.6 16.7 16.8 16.9 16.9.1 16.9.2 16.9.3 Langmuir-Hinshelwood Reaction 205 Surface Nucleation 206 Nucleation on a Surface during Vapor Deposition Cluster Formation 207 Rate Equations 209 Thin Films 210 Epitaxy 210 Deposited Surface Layers 212 Surface Reconstruction 213 Amorphous Deposits 214 Surface Modification 217 Fractal Deposits 217 Strain Energy and Misfit Dislocations 219 Strained-Layer Growth 223 Surface Modulation 223 Strained-Layer Superlartice 223 Graded-Strain Layers 224 17 Thin-Film Deposition 17.1 17.2 17.3 17.4 17.5 17.6 17.7 17.8 17.9 17.10 Liquid Phase Epitaxy 227 Growth Configurations for LPE 228 Chemical Vapor Deposition 229 Metal-Organic Chemical Vapor Deposition Physical Vapor Deposition 234 Sputter Deposition 235 Metallization 235 Laser Ablation 236 Molecular Beam Epitaxy 237 Atomic Layer Epitaxy 238 227 18 Plasmas 18.1 18.2 18.3 18.4 18.5 18.6 18.7 Direct Current (DC) Plasmas 241 Radio-Frequency Plasmas 243 Plasma Etching 245 Plasma Reactors 247 Magnetron Sputtering 249 Electron Cyclotron Resonance 251 Ion Milling 252 241 19 Rapid Thermal Processing 253 19.1 19.2 19.3 19.4 19.5 19.6 Rapid Thermal Processing 253 Rapid Thermal Processing Equipment Radiative Heating 254 Temperature Measurement 256 Thermal Stress 257 Laser Heating 258 254 233 206 IX X Contents 20 Kinetics of First-Order Phase Transformations 20.1 20.2 20.3 20.4 20.5 20.5.1 20.5.2 20.6 20.6.1 20.6.2 20.7 20.8 20.9 20.10 20.11 20.11.1 20.11.2 General Considerations 259 The Macroscopic Shape of Crystals 261 General Equation for the Growth Rate of Crystals 262 Kinetic Driving Force 263 Vapor-Phase Growth 264 Equilibrium 264 Kinetics of Vapor-Phase Growth 265 Melt Growth 267 Early Models for Melt Growth 268 Melt Growth Rates 269 Molecular Dynamics Studies of Melt Crystallization Kinetics The Kossel-Stranski Model 272 Nucleation of Layers 273 Growth on Screw Dislocations 275 The Fluctuation Dissipation Theorem 277 Determination of the Kinetic Coefficient 277 Experimental Determination of Surface Tension 281 259 21 The Surface-Roughening Transition 21.1 21.2 21.3 21.4 21.5 21.5.1 21.5.2 21.5.3 21.5.4 21.5.5 21.6 21.6.1 21.6.2 21.7 21.8 21.9 Surface Roughness 283 The Ising Model 284 Cooperative Processes 285 Monte Carlo Simulations of Crystallization 287 Equilibrium Surface Structure 288 Thermodynamic Model for Surface Roughness 288 Application of Surface Roughening to Materials 291 Snow Flakes 294 Rate-Theory Analysis of Surface Roughness 295 Surface Roughness in the Ising Model 297 Computer Simulations 298 Determination of the Kinetic Coefficient 301 Simulations of Silicon Growth 302 Growth Morphologies 304 Kinetic Roughening 306 Polymer Crystallization 308 22 Alloys: Thermodynamics and Kinetics 311 22.1 22.2 22.3 22.4 22.5 22.6 Crystallization of Alloys 311 Phase Equilibria 313 Regular Solution Model 314 Near-Equilibrium Conditions 316 Phase Diagrams 317 The DLP Model 320 283 269 Contents 23 Phase Separation 23.1 23.2 23.3 23.4 Ordering versus Phase Separation 323 Phase Separation 324 Analytical Model for Spinodal Decomposition 326 Microstructure Resulting from Phase Separation 328 323 24 Non-Equilibrium Crystallization of Alloys 24.1 24.2 24.3 24.4 24.5 24.6 Non-Equilibrium Crystallization 331 Experiment 331 Computer Modeling 333 Analytical Model 335 Comparison with Experiment 336 Crystallization of Glasses 338 331 25 Coarsening, Ripening 341 25.1 25.2 25.3 ISA 25.5 25.6 25.7 25.8 Coarsening 341 Free Energy of a Small Particle 341 Coarsening in a Solution 342 Coarsening of Dendritic Structures 344 Sintering 345 Bubbles 346 Grain Boundaries 347 Scratch Smoothing 348 26 Dendrites 26.1 26.2 26.3 26.4 26.5 26.6 Dendritic Growth 351 Conditions for Dendritic Growth Simple Dendrite Model 353 Phase Field Modeling 358 Faceted Growth 358 Distribution Coefficient 358 351 27 Eutectics 27.1 27.2 27.2.1 27.2.2 27.2.3 27.3 27.3.1 27.3.2 27.3.3 27'A 27.5 27.6 Eutectic Phase Diagram 361 Classes of Eutectic Microstrucrures 362 Class I Eutectics 362 Class II Eutectics 365 Class III Eutectics 367 Analysis of Lamellar Eutectics 367 Curvature of the Interface 368 Diffusion 370 Calculation of Eutectic Interface Shape 372 Off-Composition Eutectics 373 Coupled Growth 374 Third-Component Elements 378 351 361 XI XII Contents 28 Castings 28.1 28.2 Grain Structure of Castings 381 Dendrite Remelting 382 381 Subject Index by Page 387 Subject Index by Chapter Sections 403