Understanding Solid State Physics Sharon Ann Holgate (И CRC Press Taylor & Francis Group Boca Raton London NewYork CRC Press is an imprint of the Taylor & Francis Group, an informa business A TAYLORS FRANCIS BOOK
Contents Preface Author Further Acknowledgments xiii xv xvii Chapter 1 Introduction 1 Chapter 2 Crystal Clear: Bonding and Crystal Structures 5 2.1 Bonding in Solids 6 2.1.1 Electrons in Atoms 6 2.1.2 Ionic Bonding 8 2.1.3 Covalent Bonding 12 2.1.4 Metallic Bonding 13 2.1.5 van der Waals Bonding 15 2.1.6 Hydrogen Bonding 16 2.1.7 Mixed Bonding 20 2.2 Crystalline Solids 21 2.2.1 Describing Crystal Structures 22 2.2.2 Crystalline Structures 29 2.2.3 Quasicrystals 48 2.2.4 Liquid Crystals 49 2.2.5 Allotropes and Polymorphs 49 2.2.6 Single Crystals and Polycrystals 51 2.2.7 Directions, Planes, and Atomic Coordinates 52 Further Reading 57 Selected Questions From Questions and Answers Manual 58 Chapter 3 The Rejection of Perfection: Defects, Amorphous Materials, and Polymers 61 3.1 Defects 62 3.1.1 Point Defects 62 3.1.2 Dislocations 68 3.2 Amorphous Materials 73 3.2.1 Structure of Amorphous Materials 73 3.2.2 Models of Amorphous Structures 75 3.2.3 Glasses 77 3.2.4 Preparation of Amorphous Materials 80 3.3 Polymers 85 3.3.1 Structure of Polymers 86 vii
viii Contents 3.3.2 Thermoplastics 88 3.3.3 Thermosets 90 3.3.4 Elastomers 90 3.3.5 Additives 92 Further Reading 93 Selected Questions From Questions and Answers Manual 93 Chapter 4 Stressed Out: The Mechanical Properties of Solids 95 4.1 Introduction to Mechanical Properties of Solids 95 4.1.1 Stress and Strain 96 4.1.2 Plastic Deformation 102 4.1.3 Testing, Testing 106 4.1.4 Elasticity Ill 4.1.5 Hardness 115 4.2 The Right Material for the Job 118 4.2.1 Alloys and Composites 118 4.2.2 Altering the Mechanical Properties of a Solid 119 4.2.3 Recycling 121 Further Reading 123 Selected Questions From Questions and Answers Manual 123 Chapter 5 In, Out, Shake It All About: Diffraction, Phonons, and Thermal Properties of Solids 125 5.1 Diffraction 126 5.1.1 Propagation of Electromagnetic Radiation 126 5.1.2 How Waves Interact with Crystalline Solids 127 5.1.3 Obtaining X-Ray Diffraction Patterns 132 5.1.4 Electron and Neutron Diffraction 135 5.2 Lattice Vibrations and Phonons 139 5.2.1 Atomic Vibrations in Crystalline Solids 141 5.2.2 Phonons 143 5.3 Thermal Properties 144 5.3.1 Specific Heat 144 5.3.2 Thermal Conductivity 149 5.3.3 Thermal Expansion 150 Further Reading 154 Selected Questions From Questions and Answers Manual 154 Chapter 6 Unable to Resist: Metals, Semiconductors, and Superconductors 157 6.1 Free Electron Models of Electrical Conduction 158 6.1.1 Overview of Electrical Conduction 158 6.1.2 Drude's Classical Free Electron Model 164 6.1.3 Pauli's Quantum Free Electron Model 165
Contents ix 6.2 Energy Band Formation 174 6.2.1 Nearly Free Electron Model 175 6.2.2 Tight-Binding Model 177 6.3 Simple Band Theory 180 6.3.1 Application of Band Theory to Real Solids 180 6.3.2 Density of States in Energy Bands 184 6.4 Elemental and Compound Semiconductors 185 6.4.1 Intrinsic and Extrinsic Semiconductors 185 6.4.2 Motion of Charge Carriers in Semiconductors 197 6.5 Superconductivity 201 6.5.1 Introduction to Superconductivity 201 6.5.2 Superconductor Technology 211 Further Reading 213 Selected Questions From Questions and Answers Manual 213 Chapter 7 Chips with Everything: Semiconductor Devices and Dielectrics 215 7.1 Introduction to Semiconductor Devices 216 7.1.1 p-n Junctions 216 7.1.2 Bipolar Junction Transistors 223 7.1.3 Field-Effect Transistors 225 7.2 Optoelectronic Devices 230 7.2.1 Interaction Between Light and Semiconductors 230 7.2.2 LEDs 235 7.2.3 Semiconductor Lasers 238 7.2.4 Solar Cells 240 7.2.5 MOS Capacitor 242 7.3 Device Manufacture 243 7.3.1 Crystal Growth 244 7.3.2 Epitaxial Growth Methods 247 7.3.3 Deposition 249 7.3.4 Doping Semiconductors 252 7.3.5 MEMS 254 7.4 Dielectrics 254 7.4.1 Introduction to Dielectrics 254 7.4.2 Ferroelectricity 259 7.4.3 Piezoelectricity 262 Further Reading 264 Selected Questions From Questions and Answers Manual 264 Chapter 8 Living in a Magnetic World: Magnetism and Its Applications 267 8.1 Introduction to Magnetism 268 8.1.1 The Origins of Magnetism 268 8.1.2 Magnetic Properties and Quantities 269
x Contents 8.2 Types of Magnetism 272 8.2.1 Diamagnetism 272 8.2.2 Paramagnetism 273 8.2.3 Ferromagnetism 278 8.2.4 Antiferromagnetism and Ferrimagnetism 282 8.3 Technological Applications of Magnets and Magnetism 285 8.3.1 Solenoids 285 8.3.2 Electromagnets 286 8.3.3 Permanent Magnets 287 8.3.4 Magnetic Resonance 288 8.3.5 Magnetic Recording 289 Further Reading 292 Selected Questions From Questions and Answers Manual 293 Appendix A: Some Useful Maths 295 Al Vectors 295 Vector vs. Scalar 295 Unit Vectors 295 Addition of Vectors 296 A2 Cartesian Coordinates 296 A3 Derivation of Selected Equations 298 Derivation of Equation 6.17 298 Derivation of Equation 6.18 299 Proof that n] = np (equation 6.14[b]) is valid for extrinsic as well as intrinsic semiconductors 300 Appendix B: Vibrations and Waves 301 Bl Properties of Waves 301 Electromagnetic and Elastic Waves 301 Longitudinal and Transverse Waves 302 Describing Waves 302 Velocity of Propagation 305 B2 Wave Behaviour 305 Interference 305 Diffraction 305 Diffraction Gratings 307 Appendix C: Revision of Atomic Physics 309 CI Atomic Structure and Properties 309 Atomic Structure 309 Atomic Number 309 Mass Number and Isotopes 309 Atomic Mass Units 310 C2 Electron Shell Notation 310 Atomic Shells 310
Contents xi Principal Quantum Number 312 Orbital Quantum Number 312 Magnetic Quantum Number 313 Spin Quantum Number 313 Electron Configuration of an Atom 314 Filling of Subshells 314 C3 The Periodic Table 315 Appendix D: Revision of Quantum Mechanics 321 Dl Fundamental Ideas of Quantum Theory 321 Wave-Particle Duality 321 Wave Functions 322 Quantisation 323 Heisenberg's Uncertainty Principle 323 D2 Quantum Behaviour of Particles 324 Fermions and Bosons 324 The Pauli Exclusion Principle 324 Particle in a Box 324 Appendix E: Revision of Statistical Mechanics 329 El Use of Statistics in Solid State Physics 329 E2 Probability 329 The Concept of Probability 329 Simple Probability Calculations 330 E3 Classical Statistical Mechanics 330 Gas Model 330 Configurations 331 Boltzmann's Distribution Law 332 Boltzmann Occupation Factor 332 Equipartition of Energy 332 E4 Quantum Statistics 333 Configurations of Indistinguishable Particles 333 Fermi-Dirac Statistics 333 Bose-Einstein Statistics 335 Appendix F: Glossary of Terms 337 Index 345