Research status of silicon metal

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Silicon metal has excellent physical chemical and semiconductor properties, so quickly get application in the semiconductor device, and obtained the rapid development. Such as the power rectifier instead of DC power supply before — DC generator; silicon diode, silicon transistors and other devices, there are more and more widely used. In the future, transistorized electronic instrument will obtain greater development, it will enable more consumption and more application of silicon and silicon powder. Now in the automation industry, space flight, and remote control devices are all used silicon transistor. The solar cell is made of silicon wafer can be used as power supply, but also in military reconnaissance, surveillance and tracking device to use silicon as the filter (infrared lens), in the automatic guide device of missile with silicon infrared detector. So the metal silicon preparation has become a research hotspot of scientific workers, various preparation methods have come out.

Because each silicon atom in crystal silicon with the addition of four silicon atoms form a covalent bond, the Si-Si bond length is 2.35Å, is the tetrahedral structure, similar with the diamond structure, so the silicon with high hardness, high melting point, boiling point; chemical properties of silicon is similar with carbon, germanium, tin and lead, diagonal relationship with third group B. Under normal temperature, chemical properties of silicon is extremely stable, however in the high-temperature melting state, with large chemical activity, almost no materials does not work with the molten silicon, even if the quartz is no exception; high purity silicon with high resistivity.

The ship, the space station, unmanned lighthouse, self-service relay station, carrying communication equipment, radio transistor can be used silicon solar battery as power supply; atomic battery and solar cell have the same structure, B ray discharged from the atomic reactor waste turn into electricity, small volume, low efficiency, but the life is long, the efficiency will not to reduce in a few years; used in the intensity of radiation detector and radiation laboratory; used for detector and high frequency oscillation converter radio equipment, computer and automation element; solid state amplifier radio wave generator is widely used in thermal resistance, a photosensitive resistance, thermocouple, cooler, Ferromagnetic Semiconductors, Ferroelectrics and piezoelectric body, the radio part made by iron gas, magnetostrictive ultrasonic generator and a water detector, iron voltage electrical parts, computer memory element, voltage regulator and current regulator, transmission line protection, TV devices in the sensitive element, infrared technology, the instrument remote control and automatic production equipment of converter and the transmitter, vacuum technology of oxide cathode, for telecommunications device and small energy power supply, Thermoelectric generator, cooler and a thermostat, thermoelectric converter, chemical reaction catalyst, luminescent material and other important application.

Molten salt electrolysis prepare silicon powder is a kind of new method for the preparation of silicon powder, compared with the traditional method, this method has the following advantages: electrolytic electricity and electrode is cheaper than hydrogen and other reducing agent, simple equipment, less investment, low cost, no risk of flammable and explosive like hydrogen. Molten salt electrolysis method is a good purification technology for metal powder supplier. By the electrolysis can remove the impurities that electrical activity smaller than silicon, and the electrical activity of purity greater than silicon can be present in the electrolyte melts, so the molten salt electrolysis method can be made very high purity silicon powder. Therefore, the deposition of silicon in molten salt electric has a wide application prospect, so as to get the attention of people.