"Semiconductor: 'A semiconductor is a material which has an electrical conductivity value falling between that of a conductor, such as copper, and an insulator, such as glass.'"
Materials that are useful for electronic or optical applications, such as semiconductors or optical fibers.
Atomic structure and bonding: This topic covers the fundamental principles of atoms and how they interact to form materials. It explores atomic structure, bonding types, and properties that arise from them.
Periodic table and periodic trends: The periodic table is the main organizing principle of elements in the material world. Topics such as electronegativity, ionization energy, and atomic radius help to understand the behavior of materials.
Crystallography and crystal structures: The study of crystal structures provides insights into the physical and chemical properties of materials. The topic includes crystal classification, structure, and symmetry.
Solid-state chemistry: Solid-state chemistry deals with understanding the physical and chemical properties of materials in their solid-state form. This includes the analysis of the crystal structure and bonding patterns of materials.
Electronic properties of solids: This topic is concerned with the electronic properties of materials, such as conductivity, mobility, and energy band structure. It also covers topics such as doping, semiconductors, and junctions.
Optical properties of solids: This topic explores the optical properties of materials, such as absorption, reflection, and scattering of light. It also covers various spectroscopies to analyze optical properties.
Experimental methods in materials chemistry: This topic delves into the experimental techniques used to synthesize and analyze materials. It includes topics such as X-ray diffraction, electron microscopy, mass spectrometry, and thermal analysis.
Structure-property relationships in materials: Understanding the relationship between the material's structure and its physical and chemical properties is essential in designing and developing new materials.
Nanoscience and nanotechnology: The study of materials at the nanoscale has numerous applications in fields such as electronics, sensors, and medicine.
Biomaterials: This topic is concerned with the development of materials that are compatible with living tissues and can be used in medicine or bioengineering.
Energy materials: This topic addresses the development of materials for energy storage and conversion devices such as rechargeable batteries, fuel cells, and solar cells.
Polymers: Polymers are an essential class of materials that have applications in a wide range of fields. Topics include polymer synthesis, characterization, and properties.
Surfaces and interfaces: This topic covers the fundamental principles of surfaces and interfaces of materials, including their structure, properties, and applications.
Computational methods in materials chemistry: The computational study of materials is increasingly important for predicting properties and designing new materials. Topics include molecular dynamics, quantum mechanics, and density functional theory.
Silicon: Most commonly used material in electronics due to its semiconducting properties.
Gallium Nitride (GaN): High-performance material used in microwave applications.
Graphene: A 2D material with exceptional electronic properties.
Carbon Nanotubes (CNTs): A strong and lightweight conductor with high current carrying capabilities.
Zinc Oxide (ZnO): Used in optoelectronics, sensors, and electronic devices.
Glass: A commonly used optical material due to its transparency and low cost.
Sapphire: A transparent and durable material used in high-performance optics applications.
Polymers: Used in lenses, coatings, and optical devices.
Liquid Crystals: Used in displays, polarizers, and optical devices.
Metals: Used in mirrors, reflectors, and optical devices.
"Its resistivity falls as its temperature rises; metals behave in the opposite way."
"Introducing impurities ('doping') into the crystal structure."
"When two differently doped regions exist in the same crystal, a semiconductor junction is created."
"The behavior of charge carriers, which include electrons, ions, and electron holes, at these junctions is the basis of diodes, transistors, and most modern electronics."
"Some examples of semiconductors are silicon, germanium, gallium arsenide, and elements near the so-called 'metalloid staircase' on the periodic table."
"After silicon, gallium arsenide is the second-most common semiconductor and is used in laser diodes, solar cells, microwave-frequency integrated circuits, and others."
"The electrical properties of a semiconductor material can be modified by doping and by the application of electrical fields or light."
"Semiconductor devices can display a range of different useful properties, such as passing current more easily in one direction than the other, showing variable resistance, and having sensitivity to light or heat."
"The conductivity of silicon is increased by adding a small amount (of the order of 1 in 108) of pentavalent (antimony, phosphorus, or arsenic) or trivalent (boron, gallium, indium) atoms."
"This process is known as doping."
"Apart from doping, the conductivity of a semiconductor can be improved by increasing its temperature. This is contrary to the behavior of a metal, in which conductivity decreases with an increase in temperature."
"When a doped semiconductor contains free holes, it is called 'p-type,' and when it contains free electrons, it is known as 'n-type'."
"The p–n junctions between these regions are responsible for the useful electronic behavior."
"Using a hot-point probe, one can determine quickly whether a semiconductor sample is p- or n-type."
"The first practical application of semiconductors in electronics was the 1904 development of the cat's-whisker detector, a primitive semiconductor diode used in early radio receivers."
"Developments in quantum physics led in turn to the invention of the transistor in 1947."
"The integrated circuit was invented in 1958."
"A few of the properties of semiconductor materials were observed throughout the mid-19th and first decades of the 20th century."
"The modern understanding of the properties of a semiconductor relies on quantum physics to explain the movement of charge carriers in a crystal lattice."