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Hyperscript

Defects in Crystals

© H. Föll

Contents

Hyperscripts of AMAT:
General Information

Index

1. Introduction

1.1 Scope of the Course
General outline, Relation to other courses:
Required background knowledge
Organizational remarks
1.2 Topics for Seminar
Suggested Topics for Seminar
Rules for seminar
1.3 General Classification and Properties of Defects
Classification of defects
Materials properties and defects
The larger view and complications

2. Properties of Point Defects

2.1 Intrinsic Point Defects and Equilibrium
Single vacancies and interstitials
Frenkel and Schottky defects
Mixed point defects
2.2 Extrinsic Point Defects and Agglomerates
Impurity atoms; interaction with intrinsic defects
Global and local equilibrium, agglomeration
2.3 Point Defects in Semiconductors like Silicon
The special status of Silicon with respect to point defects and diffusion
2.4 Point Defects in Ionic Crystals
Differences in notations, the role of the chemical potential
Working with the different notation, examples

3. Point Defects and Diffusion

3.1 General Remarks
Ficks laws, relation between phenomenological view and atomic view
Technological relevance and open questions
3.2 Atomic Mechanisms of Diffusion
Vacancy and interstitial mechanisms, kick-out and exotic mechanisms
Self diffusion
Impurity diffusion
3.3 Experimental Approach to Diffusion Phenomena
Review of methods
Tracer methods
Working with the different notation, examples

4. Experimental Techniques for Studying Point Defects

4.1 Equilibrium Techniques
Differential volume expansion
Positron annihilation
Some other methods
4.2 Non-Equilibrium Techniques
Quenching and related methods
Some specialities
Specialties
Ionic crystals and special methods

5. Dislocations

5.1 Basics of Dislocations Crystals
Burgers- and line vectors.
Volterra definition of dislocations
5.2 Elasticity Theory, Energy and Forces
Elasticity theory of dislocations
Energies, forces, interactions
5.3 Movement of Dislocations
Basics, Peierls potential, kinks and jogs
Climb processes, interaction with point defects
5.4 Partial Dislocations and Stacking Faults
Energy consideration, partial dislocations in fcc crystals
Stacking faults and point defects
5.5 Dislocations and Plastic Deformation
Some general considerations, theory of hardening
Some specifics for important lattices and materials

6. Observation of Dislocations

6.1 Decoration and Microscopy
Preferential etching
IR - microscopy and others
6.2 X-ray Topography
Principle and examples
6.3 Transmission Electron Microscopy
Basics and contrast conditions
Possibilities and limitations

7. Grain Boundaries

7.1 Coincidence Lattice. O-lattice and DSC lattice for grain Boundaries
Twin boundaries to get the idea
The coincidence lattice and the O-lattice
The DSC-lattice and grain boundary dislocations
7.2 Case Studies
Tilt boundaries
Twist boundaries
Complicated Boundaries
7.3 Bollmanns O-Lattice Theory
Basic Concept
Working with the O-Lattice
The Significance of the O-Lattice

8. Phase Boundaries

8.1 Generalization of the O-lattice model
Misfit dislocations
a more general view
8.2 Case studies
Pd2Si as a simple model of a phase boundary
The Ni - Si systems and its intricacies
8.3 Steps in Interfaces
The Relation Between Steps and Dislocations in S=3 Boundaries
Open Questions