Silicon

Silicon (Latin: silicium) is the chemical element in the periodic table that has the symbol Si and atomic number 14. A tetravalent metalloid, silicon is less reactive than its chemical analog carbon. It is the second most abundant element in the Earth's crust, making up 25.7% of it by weight. It occurs in clay, feldspar, granite, quartz and sand, mainly in the form of silicon dioxide (also known as silica) and silicates (compounds containing silicon, oxygen and metals). Silicon is the principal component of glass, cement, ceramics, most semiconductor devices, and silicones, the latter a plastic substance often confused with silicon. Silicon is widely used in semiconductors because the semiconductor Germanium has a problem with reverse leakage current flow, and because its native oxide forms better semiconductor/dielectric interfaces than almost all other material combinations.

Applications

Silicon is a very useful element that is vital to many human industries. Silicon dioxide in the form of sand and clay is an important ingredient of concrete and brick and is also used to produce Portland cement. Silicon is a very important element for plant and animal life. Diatoms extract silica from water to build their protective cell walls. Other uses:

Related Topics:
Silicon dioxide - Sand - Clay - Concrete - Brick - Portland cement - Plant - Animal - Diatom

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• Pottery/Enamel - It is a refractory material used in high-temperature material production and its silicates are used in making enamels and pottery.
• Steel - Silicon is an important constituent of some steels.
• Bronze - Most bronze produced is an alloy of copper and silicon.
• Glass - Silica from sand is a principal component of glass. Glass can be made into a great variety of shapes and with a many different physical properties. Silica is used as a base material to make window glass, containers, and insulators, and many other useful objects.
• Abrasives - Silicon carbide is one of the most important abrasives.
• Semiconductor - Ultrapure silicon can be doped with other elements to adjust its electrical response by controlling the number and charge (positive or negative) of current carriers. Such control is necessary for transistors, solar cells and other semiconductor devices which are used in electronics and other high-tech applications.
• Photonics - Silicon can be used as a continuous wave raman laser to produce coherent light with a wavelength of 1,698 nm.
• Medical materials - Silicones are flexible compounds containing silicon-oxygen and silicon-carbon bonds; they are widely used in applications such as artificial breast implants and contact lenses.
• LCDs and solar cells - Hydrogenated amorphous silicon has shown promise in the production of low-cost, large-area electronics in applications such as LCDs. It has also shown promise for large-area, low-cost solar cells.
• Construction - Silica is a major ingredient in bricks because of its low chemical activity.