Semiconductors

Abstract

The article contains sections titled: 1. Definition of Semiconductors 2. History 3. Theory 3.1. Structure of Semiconductor Crystals 3.2. Conduction Mechanism of Semiconductor Materials 3.2.1. Band Model 3.2.2. Doping 3.2.3. The p ‐ n Junction 3.3. Lifetime and Recombination of Charged Particles 3.4. Effect of Various Factors on Semiconductors 3.4.1. Effect of Radiation 3.4.2. Behavior in a Magnetic Field 3.4.3. Behavior under High Electric Field 3.4.4. Semiconductor ‐ Metal Contacts 4. Materials, Properties, and Manufacture 4.1. Outline 4.1.1. Requirements for Commercial Use 4.1.2. Properties and Uses 4.1.2.1. Group IV Elements 4.1.2.1.1. Germanium 4.1.2.1.2. Diamond 4.1.2.2. Others 4.1.2.2.1. Group VI Elements 4.1.2.2.2. Multicomponent Chalcogenides 4.1.2.2.3. Oxide Semiconductors 4.1.2.2.4. Organic Semiconductors 4.2. Compound Semiconductors 4.2.1. Properties 4.2.2. Single Crystals 4.2.2.1. Boat‐Grown (BG) Method 4.2.2.2. Liquid‐Encapsulated Czochralski (LEC) Method 4.2.2.3. Comparison of the BG and LEC Methods 4.2.3. Wafer Processing 4.2.3.1. Slicing 4.2.3.2. Lapping and Polishing 4.2.3.3. Surface Defects of the Polished Wafer 5. Epitaxy 5.1. Liquid‐Phase Epitaxy (LPE) 5.1.1. Principles and Apparatus 5.1.2. LPE of AlGaAs 5.2. Vapor‐Phase Epitaxy (VPE) 5.3. Organometallic Vapor‐Phase Epitaxy (OMVPE) 5.3.1. Principles and Apparatus 5.3.2. Operating Conditions 5.4. Molecular Beam Epitaxy (MBE) 5.4.1. Principles and Apparatus 5.4.2. Gas‐Source MBE 6. Characterization 6.1. Specific Resistivity 6.2. Lifetime of Charge Carriers 6.3. Crystal Defects 6.3.1. X‐Ray Method 6.3.2. Electron‐Beam Diffraction 6.3.3. Electron Microscopy 6.3.4. Etching 6.4. Contamination of the Wafer Surface 7. Semiconductor Devices 7.1. Brief Description of Various Devices 7.1.1. Diodes 7.1.2. Transistors 7.1.3. Integrated Circuits 7.1.3.1. Memory 7.1.3.2. Logic Circuits 7.1.3.3. Analog Integrated Circuits 7.1.4. Hybrid Integrated Circuits 7.1.5. Application‐Specific Integrated Circuits (ASICs) 7.2. Wafer Fabrication 7.2.1. Formation of Insulation Layer 7.2.2. Lithography 7.2.3. Doping 7.2.3.1. Thermal Diffusion 7.2.3.2. Ion Implantation 7.2.4. Etching 7.2.5. Washing 7.2.6. Wiring Technology 8. Supporting Industries 8.1. Building 8.2. Clean Room 8.3. Ultraclean Water 8.4. Gases 8.5. Other Chemicals 8.5.1. Quartz 8.5.2. Pyrolytic Boron Nitride 8.5.3. Graphite 8.5.4. Others 9. Environmental Aspects 9.1. Gases 9.2. Liquid Chemicals 9.3. Metals 9.4. Chlorofluorocarbons (CFCs) 10. Economics

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