V

CONTENTS

INTRODUCTION...... 1

Chapter 1 THE CHALCOGENS AND THEIR COMBINATIONS

1.1 The Chalcogens...... 4 1.1.1 Sulphur (S)...... 4 1.1.2 Selenium (Se)...... 9 1.1.3 Tellurium (Te)...... 13 1.2 The General Crystallo-chemical Properties of the Chalcogens...... 15 1.3 The Chalcogen Alloys and Compounds...... 17 1.4 The Binary Compounds and the Alloys of Chalcogens with Pnictide Elements...... 21 1.4.1 The phosphorus chalcogenides...... 21 1.4.2 The arsenic chalcogenides...... 24 1.4.3 The antimony chalcogenides...... 29 1.5 The Binary Compounds and Alloys of Chalcogens with Tetrahedral Elements ...... 31 1.5.1 The silicon chalcogenides...... 31 1.5.2 The germanium chalcogenides...... 34 1.5.3 The tin chalcogenides...... 39 1.6 Other Binary Chalcogenides...... 41 1.6.1 The chalcogenides based on heavy elements...... 41 1.6.2 The chalcogenides based on light elements ...... 42 1.6.3 Alkali-chalcogenide systems...... 43 1.6.4 Halo-chalcogenide systems...... 44 1.7 The Ternary Chalcogenides...... 44 1.7.1 The chalcogenide systems based on antimony, germanium and tin ...... 44 1.7.2 The phospho-chalcogenide systems ...... 53 1.7.3 The chalcogenide systems with silicon...... 56 1.7.4 The oxy-chalcogenide glasses...... 60 1.7.5 The halo-chalcogenide systems...... 61 1.7.6 The chalcogenide systems with metals...... 65 1.7.7 Other ternary chalcogenide systems...... 86 1.8 Quaternary Chalcogenide Glasses and more Complex Glasses ...... 89 Chapter 2 PHYSICO-CHEMICAL PROPERTIES OF CHALCOGENS AND BINARY CHALCOGENIDE GLASSES 2.1 General properties...... 103 2.1.1 Metastability of glass ...... 103 2.1.2 Preparation techniques ...... 108 2.1.3 Impurities and purification...... 110 2.1.4 Mechanical properties...... 111 vi

2.1.5 Thermal and thermo-electrical properties...... 114 2.1.6 Electrical conduction...... 115 2.1.7 Optical absorption ...... 117 2.1.8 Dielectric properties ...... 119 2.1.9 Magnetic susceptibility ...... 120 2.1.10 The influence of water adsorption ...... 122 2.1.11 The additivity method for the determination of the properties of complex glasses...... 123 2.1.12 Survey of the general properties of the non-crystalline chalcogenides...... 126 2.2 Properties of Non-crystalline Chalcogens...... 127 2.2.1 Sulphur...... 127 2.2.2 Selenium...... 128 2.2.3 Tellurium...... 134 2.2.4 The chalcogen-chalcogen systems ...... 136 2.3 Properties of Non-crystalline Binary Chalcogenides...... 146 2.3.1 Phosphorus-chalcogen...... 146 2.3.2 Arsenic-chalcogen ...... 152 2.3.3 Antimony-chalcogen (Sb-Ch)...... 171 2.3.4 Silicon-chalcogen (Si-Ch)...... 176 2.3.5 Germanium-Chalcogen (Ge-Ch)...... 181 2.3.6 Tin-Chalcogen (Sn-Ch)...... 193 2.3.7 Thallium-Chalcogen...... 193 2.3.8 Alkali-Chalcogenides...... 195 2.3.9 Bismuth-Chalcogen (Bi-Ch)...... 195 2.3.10 Halogen-Chalcogen...... 196 2.3.11 Heavy metal-Chalcogen ...... 197 2.3.12 Silver-Chalcogen (Ag-Ch)...... 199 2.3.13 Silver-selenium (Ag-Se)...... 199 2.3.14 Silver-(S,Se)...... 199 2.3.15 Silver-(S,Te)...... 199 2.3.16 Oxygen-Chalcogen (O-Ch)...... 199 2.3.17 Other binary chalcogenides ...... 201

Chapter 3 MODIFICATIONS INDUCED IN NON-CRYSTALLINE CHALCOGENIDES

3.1 Modifications Induced by Light...... 209 3.1.1 Irreversible modifications...... 211 3.1.2 Reversible modifications...... 224 3.1.3 Models for the photo-inducedprocesses...... 242 3.1.4 Models for the photo-induced anisotropy...... 255 3.1.5 Exotic photo-induced modifications...... 264 3.2 Modifications Induced by other Electromagnetic Radiations in Chalcogenide Glasses...... 266 3.2.1 Modifications induced by ultraviolet radiations ...... 267 3.2.2 Modifications induced by X-rays...... 269 3.2.3 Modifications induced by gamma rays...... 270 vii

3.3 Modifications Induced by Irradiation with Particle Beams...... 272 3.3.1 Modifications induced by electron beams...... 272 3.3.2 Modifications induced by ion beams...... 277 3.4 Modifications Induced by Electric and Magnetic Fields...... 277 3.5 Mechanically Induced Modifications...... 280 3.5.1 Modifications induced by pressure ...... 280 3.5.2 Anisotropy induced by mechanical deformations ...... 282 3.6 Effects Induced by Ultrasounds...... 282 3.7 Thermally Induced Modifications...... 283

Chapter 4 APPLICATIONS

4.1 Ovonic Devices...... 293 4.1.1 Phase-change switches...... 293 4.1.2 Hybrid amorphous/crystalline transistors...... 299 4.1.3 Thermo-switches ...... 301 4.2 Xerography and X-Ray Radiography...... 302 4.3 Holography...... 308 4.4 Photo-recording...... 315 4.4.1 Photo-thermal recording...... 315 4.4.2 Materials for recording with bubbles...... 320 4.4.3 Thermo-plastic recording...... 321 4.4.4 Materials for photo- and electron-beam recording...... 323 4.5 Photolithography...... 328 4.6 TV Pick-up Tubes (Vidicon)...... 333 4.7 Radiation Sensors and Measuring Devices...... 338 4.7.1 Detectors of radiation and radiation amplifiers...... 338 4.7.2 Radiometric Devices...... 341 4.7.3 Solid state integrators ...... 345 4.8 Acousto-optical Devices...... 347 4.9 Chemical Sensors and other Devices...... 348 4.9.1 Chemical remote sensors...... 348 4.9.2 Ion-sensitive electrodes...... 348 4.9.3 Electrical resistance elements...... 349 4.9.4 Optical fibre sensors...... 349 4.10 Solid State Batteries...... 350 4.11 Infrared Optical Media...... 350 4.12 Components for Integrated Optics...... 352 4.12.1 Optical fibres...... 352 4.12.2 Planar waveguides ...... 354 4.12.3 Kinoform optical elements...... 356 4.12.4 Chalcogenide materials in optoelectronics...... 358 4.13 Applications of Heavy metal – Chalcogen Compounds and Alloys...... 360

Subject Index...... 368