Introduction of Silicon and Its Use


Silicon is an important semiconductor material with two different allotropes, amorphous silicon powder and crystalline silicon. It has a solid structure of diamond crystal and clear metallic luster. Under the heat, it can react with halogen, nitrogen, carbon and other nonmetal, or certain metals, such as Mg, Ca, Fe, Pt, etc. The generated silicide, usually cannot dissolve in inorganic acid, but can dissolve in aqueous alkali, produce alkali metal silicate solution and give off hydrogen. In hot temperature, it can react with water vapor. Existing in earth crust in the atomic proportion of 16.7%, silicon is widely distributed in nature. As one of intergral elements of forming quartz sand and silicates, it is very essential in composing rocks and minerals.


Excepting oxygen, silicon is the most abundant substance in earth crust. Just as carbon is the basis of organic life, it is in the same important position in composing crust. Silicon-containing lithosphere is the most basic element in forming earth crust. The rocks contained in the lithosphere are mainly composed of silica and various silicates.


We can get amorphous silicon powder when magnesium reduces silica. And get crystalline silicon when carbon reduces silicon dioxide in an electric furnace. When hydrogen reduces trichloroethane or silicon tetrachloride, we can get high-purity silicon powder, which is generally used in electronics industry. Silicon is applied to manufacture high silicon cast iron, silicon steel and other alloys, organic silicon compound and silicon tetrachloride, etc. It is an important semiconductor material. Monocrystalline silicon doped with slight impurities can manufacture high-power transistors, rectifier and solar batteries.


In 1823, Swedish chemist got amorphous silicon by co-heating the potassium fluosilicate and excessive potassium metal powder. Although there were many scientists had made this substance before, silicon wasn’t identified as a new element formally until that one type of this substance made by one Swedish chemist can burn in oxygen.


Improving the quality and yield of crops, silicon becomes an important nutritional element contained in plants. At the same time, as health element and quality element, it can also increase the sugars, vitamin C and solids contained in crops and decrease fruit acidity, shape fruit figure, polish fruit surface, make them vivid and delicious. With the help of these fuctions above, the quality and commodity of fruits can be improved by 25%-50%. By forming silicide cells in the fruit epidermis, silicon can also inhibit water evaporating, increase the firmness of fruit and furthermore make it behave better on passage.


It is also a main material in producing isotope battery transducer, which is a device of translating isotope heat source into electrical energy. Made by silicon-germanium alloy, the transducer can still sustain good mechanical properties and oxidation resistance even its temperature arrives at 1000 degrees Celsius at work. Additionally, this kind of transducer won’t evaporate and be poisonous easily under high temperature, either in vacuum or air.


Silicon is also a semiconductor material, can be used for producing semiconductor devices, integrated circuits. It can also be applied to maufacturing automotive and machinery parts in the form of alloy (such as silicon alloy). And be used in metal ceramics together with ceramic material. And producing glass, concrete, brick, refractory, siloxane, silane needs it too.