Imperfections and Active Centres in Semiconductors discusses principles of semiconduction theory in terms of the band model, and electrical properties as regards chemical or physical defects in the lattice structures. The book reviews the fundamental concepts of semiconductor crystals, semiconduction, silicon, and the atomic lattice of germanium. The Frenkel defect accounts for displaced atoms in the lattice that move into spaces between normal atom positions. The text describes dislocations or line defects, the motion and generation of dislocations, as well as the geometry of the dislocations in the diamond. Honrstra (1958), who shows the geometry of the dislocation structures through a diagram, also describes the geometry of more complicated types of dislocation in the diamond lattice. The book explains X-ray diffraction and crystal imperfections in which the amount of X-radiation reflected from a crystal specimen depends on the perfection or on the atomic structure of the reflecting planes. The electron microscope can reveal more detail in higher resolution, for example, the actual arrangement of the molecules around an edge dislocation has been exposed in a platinum phthalocyanine crystal. The book also describes the fabrication of semiconductor devices where the crystals are cut with an abrasive saw and then ground with fine abrasive. The text can be used by physicists, engineers, or technologists in the allied fields of solid state physics and materials engineering.

Contenu

Preface
Chapter 1 Fundamental Concepts of the Semiconductor Crystal
1.1 Introduction
1.2 Semiconduction and the Atomic Lattice of Germanium and Silicon
1.2.1 Some Elements of Crystallography
1.2.2 The Diamond Cubic Lattice and the Covalent Bond
1.2.3 Semiconduction and the Band Model
1.3 Point Defects in the Crystal
1.3.1 Vacancies and Interstitials
1.3.2 the Equilibrium Concentration of the Point Defects
Chapter 2 Dislocations or Line Defects
2.1 A Survey of Dislocation Types
2.1.1 General Considerations of the Dislocation Concept
2.1.2 The Burgers Vector
2.1.3 Edge Dislocations
2.1.4 Movement of the Edge Dislocation
2.1.5 Screw Dislocations
2.1.6 Other Dislocation Types
2.2 The Motion and Generation of Dislocations
2.2.1 The Interaction of Dislocations and Jog Formation
2.2.2 The Climb of Dislocations and the Behaviour of the Jogs
2.2.3 Dislocation Sources
2.2.4 Partial Dislocations
2.2.5 Helical Dislocations and their Formation
2.3 The Geometry of the Dislocations in the Diamond Lattice
2.3.1 Structure of the Simple Dislocations
2.3.2 The Structure of Other Dislocation Types
2.3.3 the Atomic Arrangement of Partial Dislocations and Stacking Faults
Chapter 3 The Detection of Dislocations by X-Ray and Other Techniques
3.1 X-Ray Diffraction and Crystal Imperfections
3.1.1 An Introduction to the Elementary Theory
3.1.2 X-Ray Line Broadening and the Crystal Quality
3.1.3 Dislocation Density from Diffraction Data
3.1.4 Crystal Assessment by the Laue and Other X-Ray Techniques
3.2 The Detection of Defects by Microscopy and Other Methods
3.2.1 X-Ray Microscopy
3.2.2 Decoration Methods and Infra-Red Microscopy
3.2.3 Electron Microscopy
3.2.4 Other Techniques for Observing the Dislocations
Chapter 4 Plastic Deformation and Twinning
4.1 Deformation Experiments and Behaviour of the Dislocations
4.1.1 General Observations of the Slip Mechanism
4.1.2 The Stress-Strain Relationship
4.1.3 Plastic Bending and the Distribution of the Dislocations
4.1.4 Further Deformation Experiments
4.1.5 Current Theories of the Plastic Behaviour of Semiconductor Crystals
4.1.6 Work-Hardening
4.2 Twinning in Germanium and Silicon
4.2.1 Basic Concepts and Experimental Observations
4.2.2 Deformation or Mechanical Twinning
4.2.3 Interpretation of the Twinning Mechanisms
Chapter 5 The Growth of Single Crystal Crystals
5.1 Crystal Growing Techniques and Crystal Quality
5.1.1 The Vertical Pulling (Czochralski) Method
5.1.2 Physical Conditions and Growth Procedure
5.1.3 Horizontal Crystal Growth by Zone Melting
5.1.4 The Vertical Floating Zone Method for Silicon Crystals
5.1.5 The Stability of the Liquid Zone
5.1.6 Other Methods of Crystal Growth
5.2 The Temperature Distribution as a Crystal Growth Parameter
5.2.1 Thermal Conditions During Crystal Pulling
5.2.2 The Liquid-Solid Interface
5.2.3 External Features of the Grown Crystal
5.3 Thermal Stress in the Growth of Crystals
5.3.1 Observations of the Etch Pit Distribution
5.3.2 Thermal Stresses and the Plastic Deformation of the Crystal
5.3.3 Thermal Deformation and the Etch Pit Patterns
5.3.4 The Active Dislocations
5.3.5 Dislocation-Free Crystals
5.4 Theories of Crystal Growth Applied to Semiconductors
5.4.1 The Stepped Growth Surface
5.4.2 The Spiral Terrace
5.4.3 Crystal Growth from the Melt
5.4.4 Crystallization of the Diamond Lattice
Chapter 6 The Distribution and Control of Impurities
6.1 Simple Freezing and the Solute Distribution
6.1.1 Some Theoretical Considerations
6.1.2 Constitutional Supercooling in the Melt
6.1.3 The Origin of the Impurity Striations
6.2 Liquid Zone Techniques for the Distribution of Impurities
6.2.1 Zone Refining Methods
6.2.2 Solute Distribution According to Theory
6.2.3 The Ultimate Solute Distribution
6.2.4 Uniform Distribution by Zone Levelling
6.2.5 Other Methods for the Uniform Doping of Crystals
Chapter 7 The Chemical and Physical Behaviour of the Impurity Elements
7.1 Methods for the Determination of Impurities in Semiconductors
7.1.1 Spectrographic Analysis
7.1.2 The Mass Spectrometer
7.1.3 Radioactivation Analysis
7.1.4 X-Ray Determination of the Lattice Parameters and Precision Density Measurements
7.1.5 Electrical Methods
7.2 The Solubility of the Active Impurities in Germanium and Silicon
7.2.1 The Nature of the Atoms
7.2.2 The Distribution Coefficient, k
7.2.3 Solid Solubility and Retrograde Solubility
7.2.4 The Determination of Solubility Data
7.2.5 Theoretical Expressions for the Distribution Coefficient
7.2.6 The Interaction of Defects and the Law of Mass Action
7.2.7 The Effect of Ion-Pairing on the Solid Solubility
7.3 Diffusion of Chemical Impurities
7.3.1 The Fundamental Laws of Diffusion
7.3.2 The Substitutional Diffusion Mechanism
7.3.3 Other Factors Affecting Diffusion
7.3.4 The Diffusion of Copper in Germanium and Silicon
7.4 The Precipitation of Impurity Elements
7.4.1 The Kinetics of Copper Precipitation in Germanium
7.4.2 Nickel Precipitation in Germanium
7.4.3 Dislocations and Other Precipitation Nuclei
7.4.4 Lithium Precipitation in Germanium and Silicon
7.5 Thermal Acceptors and the Electrical Behaviour of Semiconductors
7.5.1 Heat Treatment and the Role of Copper in Germanium
7.5.2 The Effect of Oxygen in Silicon
7.5.3 Crystal Growth Parameters and the Distribution of Oxygen in Silicon
7.5.4 Theoretical Considerations of the Thermal Behaviour
7.5.5 Oxygen in Germanium
Chapter 8 Defects and the Semiconducting Properties of Germanium and Silicon
8.1 The Influence of Dislocations on the Electrical Properties
8.1.1 Changes in Resistivity Produced by Plastic Deformation
8.1.2 Scattering of the Charge Carriers by Dislocations
8.1.3 Lifetime and the Recombination of Carriers at Dislocations
8.1.4 Recombination at Low-Angle Grain Boundaries
8.2 Irradiation Damage and Semiconductor Behaviour
8.2.1 General Considerations of the Irradiation of Materials
8.2.2 Nature of the Lattice Damage
8.2.3 The Threshold Energy for Atom Displacement
8.2.4 Conductivity Variations and the Observed Energy Levels
8.2.5 Va…