Physics and chemistry of Te and HgTe-based ternary semiconductor melts / Ching-Hua Su

This book reviews the experimental measurements of density, thermal conductivity, viscosity, and electrical conductivity on the binary, pseudo-binary melts of the most advanced IR-detector material systems of HgCdTe and HgZnTe as well as the theoretical analyses of these results. The time-dependent measurements on the relaxation behavior of the thermophysical properties during rapid cooling of the melts were also performed to elucidate the characteristics of the structural fluctuation and transition of the melts. The author shows his research results which extend understanding of the solidification process in order to interpret and improve the experimental results of crystal growth and enhances the fundamental knowledge of heterophase fluctuations phenomena in the melts so as to improve the melt growth processes of all the semiconductor systems. An in-depth study on the thermophysical properties and their time-dependent structural dynamic processes taking place in the vicinity of the solid-liquid phase transition of the narrow homogeneity range HgTe-based ternary semiconductors as well as the structural analysis of the alloy homogenization process in the melt is needed to understand and to improve the crystal growth processes. This book is intended for graduate students and professionals in materials science as well as engineers preparing and developing optical devices with semiconductors. The theory of heterophase fluctuations of liquids is applicable to any many-body systems including condensed-matter physics and field theory. Publisher Preface Acknowledgements Contents Abbreviations 1 Introduction 1.1 Essences of Material Processing 1.2 HgTe-Based Ternary Systems 1.3 Thermophysical Properties References 2 Reviews on Hetero-Phase Structural Fluctuation in Semiconductor Melts 2.1 Introduction 2.2 Review of Relevant Research 2.2.1 Theoretical Investigations 2.2.2 Experimental Investigations References 3 Phase Diagrams and Associated Solution Model for the Liquid Phase of HgTe-Based Ternary Systems 3.1 Introduction 3.2 Associated Solution Model for Liquid Phase 3.2.1 Solution Thermodynamics 3.2.2 Associated Solution Model 3.3 Liquidus Equations and Optimization of Interaction Parameters 3.4 Phase Diagram and Thermodynamic Properties 3.4.1 Hg-Cd-Te Systems 3.4.2 Hg-Zn-Te Systems References 4 Density Measurements and Results 4.1 Density Measurements by Pycnometry 4.2 Sample Preparation 4.3 Experimental 4.4 Results and Discussions 4.4.1 Te Liquid 4.4.2 HgTe Melt 4.4.3 Hg0.9Cd0.1Te Melt 4.4.4 Hg0.8Cd0.2Te Melt 4.4.5 Hg0.9Zn0.1Te and Hg0.84Zn0.16Te Melts References 5 Viscosity and Electrical Conductivity Measurements and Results 5.1 Introduction 5.2 Oscillating-Cup Viscometer and Results 5.2.1 Experimental 5.2.2 Results and Discussions of HgTe Melt 5.2.3 Results and Discussions of Hg0.8C0.2Te Melt 5.2.4 Results of Hg0.84Zn0.16Te Melt and Its Relaxation Phenomenon 5.3 Transient Torque Viscometer (TTV) 5.3.1 Experimental Setup 5.3.2 Results and Discussions on Te Melt and Solid 5.3.3 Results and Discussions of Melts of HgTe, Hg0.1Cd0.9Te and Hg0.2Cd0.8Te 5.3.4 Relaxation Phenomenon References 6 Thermal Conductivity Measurements and Results 6.1 Introduction 6.2 Heat Capacity of HgCdTe and HgZnTe Melts 6.2.1 Hg1-xCdxTe Melts 6.2.2 Hg1−xZnxTe Melts 6.3 Thermal Conductivity of HgCdTe and HgZnTe Melts 6.3.1 Experimental Measurements of Thermal Diffusivity by Laser Flash Method 6.3.2 Results of Hg1−xZnxTe Pseudo-Binary Solids and Melts 6.3.3 Results of Hg1−xCdxTe Pseudo-Binary Solids and Melts 6.3.4 Results of Te-Rich HgCdTe and HgZnTe Melts 6.4 Thermal Conductivity of Te Liquid by Modified Laser Flash Measurements 6.4.1 Experimental 6.4.2 Numerical Solution 6.4.3 Graphical Solution References 7 Physics and Chemistry of Te and HgTe-Based Ternary Melts 7.1 Lorenz Numbers for the Solids/Melts of Te, HgTe, Hg0.9Cd0.1Te and Hg0.8Cd0.2Te 7.1.1 Introduction 7.1.2 Experimental Measurements on Te Solid 7.1.3 Measured Thermal Conductivity of Solids/Melts of Te and Hg1−xCdxTe 7.1.4 Measured Electrical Conductivity of Solids/Melts of Te and Hg1−xCdxTe 7.1.5 Lorenz Number 7.2 Physics and Chemistry of Te Melt 7.3 Physics and Chemistry Hg-Cd-Te System 7.3.1 Structural Transformation in the Melts 7.3.2 Viscosity of the Melts 7.3.3 Thermal Conductivity and Electrical Conductivity 7.3.4 Relaxation Phenomena 7.4 Physics and Chemistry Hg-Zn-Te System 7.4.1 Structural Transformation in the Melts 7.4.2 Viscosity of Hg0.84Zn0.16Te Melt 7.4.3 Relaxation Phenomenon 7.5 Effects on Crystal Growth Process References