Introduction to Silicon
Silicon is the 14th element in the periodic table, and the second most abundant on the earth (27.7% of the Earth's crust is made of silicon). It is also one of the most important in modern everyday living. It is used in an amazing variety of ways, from doped silicon transistors in the Playstation 2, to the silicone gel used in plastic surgery. It is the driving force behind almost all modern technology, and will remain so for the foreseeable future. It is used in medicines, cosmetics, and incorporated into food processing in the form of silicone, a synthetic polymer based on silicon. These uses make it among the most important elements currently used by man.
The Uses of Silicon
Elemental silicon is used particularly in the production of transistors, now one of the most important electrical components contributing to modern life, and is thus the driving force behind the electronic revolution. Silicon is used in transistors because of its properties as a semi-conductor and for this purpose it must be doped. Transistors are the major functional component of computers and most other modern electronic devices. Silicon is also used in solar cells (hydrogenated amorphous silicon has shown promise in producing economical cells for converting solar energy into electricity), rectifiers, and other solid-state devices which are used extensively in the electronics and space-age industries.
Silicon is also used in many non-electrical devices. In the form of sand and clay it is used to make concrete and brick; it is a useful refractory material for high-temperature work, and in the form of silicates it is used in making enamels and pottery. Silica, as sand, is a principal ingredient of glass. Silicon tetrachloride can be used to iridize glass.
Silicon is also an important ingredient in steel; silicon carbide is one of the most important abrasives and has been used in lasers to produce coherent light of 4560 A.
Silcones are important products of silicon. Hydrolysis and condensation of various substituted chlorosilanes can be used to produce a very great number of polymeric products, or silicones, ranging from liquids to hard, glasslike solids with many useful properties.