Application areas of silicon


Crystalline silicon’s color is gray-black, and the amorphous silicon is black, the density is 2.32-2.34g/cc, melting point is 1410°C, boiling point is 2355°C, crystalline silicon belongs to  atomic crystal, it is hard with metallic sheen, it has the properties of semiconductor. The chemical nature of silicon is relatively active, and it can react with a variety of elements such as oxygen compounds at high temperatures, it can not dissolve in water, nitric acid and hydrochloric acid, but it can be dissolved in hydrofluoric acid and lye. It is used for manufacturing alloys such as ferrosilicon, silicon steel, etc.. Monocrystalline is an important semiconductor material for manufacturing the power transistors, rectifiers, solar batteries, etc.. Silicon is widely distributed in nature, the Earth’s crust contains about 27.6% of it, the content is just after the oxygen, ranking the second place. The crystalline silicon’s color is dark blue, and it’s very brittle, it’s a typical semiconductor. Chemical nature is very stable. It is difficult to react with other substances except the hydrofluoric acid at room temperature.

Silicon application: high purity silicon monocrystalline is an important semiconductor material. Add a trace amount of Group IIIA element incorporated in the single crystal silicon, forming a p-type silicon semiconductor; join a trace amount of Group VA element, form the combination of n-type and p-type semiconductor, then it can be made of the solar cells, turn the radiation energy into electricity energy. In the aspect of developing energy resources is a promising material. Another widely used like diodes, transistors, thyristors, and a variety of integrated circuits (including our computer chips and CPU) are made of silicon raw materials.

Important materials of cermet, astron. Sintered the mixture of ceramic and metal, make it into metal-ceramic composites, it can resist high temperature and be very tenacious, it can be cut, not only inherits the respective advantages of metal and ceramic, also make up for both birth defects.

Optical fiber communication, the latest modern communication means. Use pure silica to draw out of a high transparency pure silica glass fiber, a laser in the passage of the glass fiber has numerous total reflection and onward transmission, instead of the cumbersome cable. The optical fiber communications have high capacity, a fine strand of glass fiber like hair, can transmit 256 telephone channels at the same time, also without electricity, magnetic interference, and they are not afraid of wiretapping, they are provided with a high degree of confidentiality.

There are some excellent performance silicon organic compounds. For example, silicone plastic coating material is excellent waterproof. Spray silicone on the walls of Underground Railroad, can solve the problem of water seepage once and for all. In the appearance of ancient artifacts, sculpture, coated with a thin layer of silicone plastic, can prevent moss breeding, resist wind and rain and weathering.

Organosilicon compound is those containing Si-O bond, and at least have one organic group is directly connected to a silicon atom in the compound, it is customary also often see the compounds that through an oxygen, sulfur, nitrogen, and others which make organic group connected to silicon atom as organic silicon compounds. Among them, silicon-oxygen bond ( -Si-0-Si- ) polysiloxane skeleton is the largest number of organic silicon compounds, the most studied, the most widely used, and more than 90% of the total amount.

Silicon is mainly in the form of compounds, second only to oxygen as the most abundant element found in the earth’s crust, accounting for about a quarter of the surface rocks, widely present in the silicate and silica. In industry, it is usually used carbon by reduction of silica in an electric furnace to obtain it. The purity of silicon which using this method obtained is 97% to 98%, and called silicon metal powder. Then recrystallized after melted it, remove impurities with acid, obtained the purity of silicon metal powder is approximately 99.7% to 99.8%. If you want to make it into the semiconductor silicon, you should also transformed it into the easy purification liquid or gas form, and then by distillation, decomposition process to obtain polysilicon. To obtain high-purity silicon powder, it requires further purification process.