Point Defect Thermodynamics of Compound Semiconductors and their Alloys

Abstract

The physical properties of crystalline solids depend on the presence of point defects. The concentrations of these defects in turn depend on the conditions of preparation and the presence of dopants. Quantitative relations between these conditions (partial pressures of components, concentrations of dopants, temperature) and the defect concentrations is arrived at on the basis of defect chemistry. Examples of pure and doped binary compounds, alloys of binary compounds, and ternary compounds, are given. Whereas binary compounds have one composition variable, the alloy systems and the ternary compounds have two. The role of phase diagrams in preparing systems of required composition and properties is stressed.

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