Silicon is a semiconductor material that can stand the test of today's device technology development better than germanium. 1966 has produced 40,000 kilograms of semiconductor-grade silicon (single crystal ultra-pure silicon with impurity content less than1109), thus manufacturing 4 billion components. By 1966, the amount of silicon used in this field has exceeded the amount of germanium.
The integrated circuit composed of silicon transistors and other components is getting higher and higher in integration and scale, while the components are getting smaller and smaller. A silicon wafer with a diameter of 75 mm can integrate tens of thousands to hundreds of thousands or even millions of components to form microelectronics, thus appearing microcomputers and microprocessors.
Growing a layer of 10-25 micron thick polysilicon film on aluminum substrate is a cheap and lightweight solar cell material, which is suitable for use in space and on the ground.
Silicon is the main material of isotope battery transducer. Transducer is a device that converts the thermal energy of isotope heat source into electrical energy. The working temperature of the transducer made of silicon germanium alloy is 1000oC, which has good mechanical properties and oxidation resistance, is not easy to evaporate and be poisoned at high temperature, and can work in vacuum and air.
The heat-resistant lightweight silicon tile used in the space shuttle can protect the fuselage from the high temperature exceeding 1000oC when the space shuttle returns to the atmosphere.
The use temperature of natural rubber and synthetic rubber is generally below 150oC, otherwise it will age and deteriorate. Silicone rubber, developed in the 1940s, is a semi-inorganic polymer elastomer with silicon-oxygen-silicon as the main chain. It has some characteristics of inorganic materials and organic materials, and has a wide range of application temperatures. Silicone rubber has excellent ozone resistance, alkali resistance, physiological inertia (it has no adverse effects on human body and can be used as a repair material for some organs, such as artificial joints) and electrical properties. Some silicone rubbers with special structures have excellent oil resistance, solvent resistance and radiation resistance, so silicone rubbers are widely used in aviation, aerospace technology, electrical and electronic industries.
Using 1 10-2 methyl vinyl silicone rubber as raw rubber and acetylene black as filler, conductive rubber can be made, which is an ideal conductive material for connecting integrated circuits and LCD screens in electronic watches.
Silicic acid can form gel in water, so it can be used to prepare adsorbent-silica gel. Silica gel is a polar adsorbent, which has strong adsorption capacity for polar substances such as H2O, and is often used as desiccant and adsorbent in industry.
The aqueous solution of sodium silicate is called sodium silicate, and it is called sodium silicate in industry. Wood and fabrics soaked in sodium silicate can be antiseptic and not easy to catch fire.
Silica sol is an aqueous dispersion with silica as the basic unit. In the process of wool textile, it can be used as a sizing agent for light textile to reduce the broken end rate of wool fibers. The coating contains silica sol, which can improve the surface heat resistance of inorganic fiber materials.
In the enamel ware manufacturing industry, the addition of silica sol can reduce the expansion coefficient and improve the adhesion to tetrafluoroethylene, which has the same effect in glass and glass ceramics. If 25-30% silica sol is added to the glass, high quality borosilicate glass can be made.
Some sodium borosilicate glasses (including sodium oxide, boron oxide and silicon oxide) are separated into two immiscible parts after heat treatment and atomic recombination. One part mainly contains silicon oxide, and the other part mainly contains sodium oxide and boron oxide. If treated with acid again, silicon dioxide will not be affected by acid, while sodium oxide and boron oxide will be dissolved in acid, leaving many holes-micropores, thus making widely used microporous glass.
Drying and sintering the microporous glass to obtain transparent glass with high silica content. It has the advantages of high temperature resistance, good thermal stability and strong ultraviolet transmittance. It can replace timely glass in many aspects and is suitable for high temperature observation windows, such as those on spacecraft. Forcing it to observe objects will not deform, because its optical uniformity is also very good.
If a small amount of silver halide is added to the ordinary sodium aluminum borosilicate glass as sensitizer and a small amount of copper is added as sensitizer, the photochromic glass of silver halide can be made by melting, annealing and proper treatment with conventional glass technology. It will change color due to different light intensity, and has important applications in strong light protection, display devices, optical information storage, vehicle windshield and so on.
Pure silicon crystal is called chronotropic. It melts into viscous liquid at 1600℃ in time, and the inside becomes irregular. When it is cooled again, it is difficult to recrystallize because of its high viscosity, and it becomes timely glass. It has many special properties, such as allowing visible light and ultraviolet light to pass through, and can be used to make ultraviolet lamps and optical instruments; It has a small expansion coefficient, can withstand drastic changes in temperature and has good acid resistance (except hydrofluoric acid), so it is often used to manufacture advanced chemical utensils.
The optical energy transmission system equipped with medical laser is made of Shi Ying optical fiber, which is not only exquisite, light and flexible, but also can transmit laser energy into human internal organs for treatment.
Double quick cement is a new type of cement, which has the characteristics of quick setting and quick hardening. The strength after pouring for one day is equivalent to that of ordinary cement pouring for 7-28 days. It can be used for slipform construction, rapid molding and demoulding of prestressed concrete members and blocks, and can also be used as self-hardening sand for the molding of shotcrete or mechanical castings in mine roadway.
Spongy elastomer made of waste tires, etc. Mixing and stirring with super glue emulsion and cement to form rubber cement. It overcomes the shortcomings of the original concrete, can prevent cracking, peeling and water absorption, and can be used for paving and building.
SiC is also called silicon carbide and emery. It has diamond-like structure, high hardness and high decomposition temperature, so it is widely used as abrasive in industry.
Silicon nitride ceramics have high strength and hardness, good thermal shock resistance and chemical corrosion resistance, low friction coefficient and self-lubrication, and are excellent wear-resistant materials. After hundreds to thousands of hours of operation, the mechanical sealing ring made of silicon nitride ceramics has less wear and the service life is several times to ten times longer than that of raw materials.
After being heated to a certain temperature, the silicon carbide far-infrared radiant panel based on silicon carbide ceramics can emit long-wave infrared rays above radiation 2- 15 micron, and has high drying efficiency for organic matter, polymer substance and water-containing substance with strong absorption peak of far infrared rays. At present, this silicon carbide far-infrared radiation board has been applied to bicycles, sewing machines and furniture. Drying of wood, leather, textiles, food and grains.