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Disilane
Disilane is a chemical compound with general chemical formula Si2R6 that was first identified in 1902 by Henri Moissan and Samuel Smiles (1877–1953) where R = H. Moissan and Smiles reported disilane as being among the products formed by the action of dilute acids on metal silicides. Although these reactions had been previously investigated by Friedrich Woehler and Heinrich Buff between 1857 and 1858, Moissan and Smiles were the first to explicitly identify disilane. They referred to disilane as ''silicoethane''. Higher members of the homologous series formed in these reactions were subsequently identified by Carl Somiesky (sometimes spelled "Karl Somieski") and Alfred Stock. At standard temperature and pressure, disilane is a colourless, acrid gas. Disilane and ethane have similar structures, although disilane is much more reactive. Other compounds of the general formula (X = hydrogen, halogen, alkyl, aryl, and mixtures of these groups) are called disilanes. Disilane is a group ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Group 14 Hydride
Group 14 hydrides are chemical compounds composed of hydrogen atoms and carbon group, group 14 atoms (the elements of group 14 are carbon, silicon, germanium, tin, lead and flerovium). Tetrahydrides The tetrahydride series has the chemical formula , with X representing any of the carbon family. Methane is commonly the result of the decomposition of organic matter and is a greenhouse gas. The other hydrides are generally unstable, poisonous metal hydrides. They take on a pyramidal structure, and as such are not polar molecules like the other p-block hydrides. Unlike other light hydrides such as ammonia, water and hydrogen fluoride, methane does not exhibit any anomalous effects attributed to hydrogen bonding, and so its properties conform well to the prevailing trend of heavier group 14 hydrides. Hexahydrides This series has the chemical formula . Ethane is commonly found alongside methane in natural gas. The other hydrides of the chemical formula are less stable than the cor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trisilane
Trisilane is the silane with the formula H2Si(SiH3)2. A liquid at standard temperature and pressure, it is a silicon analogue of propane. In contrast with propane, however, trisilane ignites spontaneously in air. __TOC__ Synthesis Trisilane was characterized by Alfred Stock having prepared it by the reaction of hydrochloric acid and magnesium silicide. This reaction had been explored as early as 1857 by Friedrich Woehler and Heinrich Buff, and further investigated by Henri Moissan and Samuel Smiles in 1902. Decomposition The key property of trisilane is its thermal lability. It degrades to silicon films and SiH4 according to this idealized equation: :Si3H8 → Si + 2 SiH4 In terms of mechanism, this decomposition proceeds by a 1,2 hydrogen shift that produces disilanes, normal and isotetrasilanes, and normal and isopentasilanes. Because it readily decomposes to leave films of Si, trisilane has been explored a means to apply thin layers of silicon for semiconductors and simi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silane
Silane (Silicane) is an inorganic compound with chemical formula . It is a colorless, pyrophoric gas with a sharp, repulsive, pungent smell, somewhat similar to that of acetic acid. Silane is of practical interest as a precursor to elemental silicon. Silanes with alkyl groups are effective water repellents for mineral surfaces such as concrete and masonry. Silanes with both organic and inorganic attachments are used as coupling agents. They are commonly used to apply coatings to surfaces or as an adhesion promoter. Production Commercial-scale routes Silane can be produced by several routes. Typically, it arises from the reaction of hydrogen chloride with magnesium silicide: : It is also prepared from metallurgical-grade silicon in a two-step process. First, silicon is treated with hydrogen chloride at about 300 °C to produce trichlorosilane, HSiCl3, along with hydrogen gas, according to the chemical equation : The trichlorosilane is then converted to a mixture ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethane
Ethane ( , ) is a naturally occurring Organic compound, organic chemical compound with chemical formula . At standard temperature and pressure, ethane is a colorless, odorless gas. Like many hydrocarbons, ethane is List of purification methods in chemistry, isolated on an industrial scale from natural gas and as a petrochemical by-product of oil refinery, petroleum refining. Its chief use is as feedstock for ethylene production. The ethyl group is formally, although rarely practically, derived from ethane. History Ethane was first synthesised in 1834 by Michael Faraday, applying electrolysis of a potassium acetate solution. He mistook the hydrocarbon product of this reaction for methane and did not investigate it further. The process is now called Kolbe electrolysis: : acetate, CH3COO− → CH3• + carbon dioxide, CO2 + electron, e− : CH3• + •CH3 → C2H6 During the period 1847–1849, in an effort to vindicate the radical theory of organic chemistry, Hermann Kolbe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digermane
Digermane is an inorganic compound with the chemical formula . One of the few hydrides of germanium, it is a colourless liquid. Its molecular geometry is similar to ethane. Synthesis Digermane was first synthesized and examined in 1924 by Dennis, Corey, and Moore. Their method involves the hydrolysis of magnesium germanide using hydrochloric acid. Many of the properties of digermane and trigermane were determined in the following decade using electron diffraction studies. Further considerations of the compound involved examinations of various reactions such as pyrolysis and oxidation. Digermane is produced together with germane by the reduction of germanium dioxide with sodium borohydride. Although the major product is germane, a quantifiable amount of digermane is produced in addition to traces of trigermane. It also arises by the hydrolysis of magnesium-germanium alloys. Reactions The reactions of digermane exhibit some differences between analogous compounds of the G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henri Moissan
Ferdinand Frédéric Henri Moissan (; 28 September 1852 – 20 February 1907) was a French chemist and pharmacist who won the 1906 Nobel Prize in Chemistry for his work in isolating fluorine from its compounds. Among his other contributions, Moissan discovered moissanite and contributed to the development of the electric arc furnace. Moissan was one of the original members of the International Atomic Weights Committee. Biography Early life and education Moissan was born in Paris on 28 September 1852, the son of a minor officer of the Eastern Railway Company, Francis Ferdinand Moissan, and a seamstress, Joséphine Améraldine (née Mitel). In 1864 they moved to Meaux, where he attended the local school. During this time, Moissan became an apprentice clockmaker. However, in 1870, Moissan and his family moved back to Paris due to war against Prussia. Moissan was unable to receive the ''grade universitaire'' necessary to attend university. After spending a year in the army, he en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wafer (electronics)
In electronics, a wafer (also called a slice or substrate) is a thin slice of semiconductor, such as a crystalline silicon (c-Si, silicium), used for Semiconductor device fabrication, the fabrication of integrated circuits and, in photovoltaics, to manufacture solar cells. The wafer serves as the substrate (materials science), substrate for microelectronic devices built in and upon the wafer. It undergoes many microfabrication processes, such as doping (semiconductor), doping, ion implantation, Etching (microfabrication), etching, thin-film deposition of various materials, and Photolithography, photolithographic patterning. Finally, the individual microcircuits are separated by wafer dicing and Integrated circuit packaging, packaged as an integrated circuit. History In the semiconductor industry, the term wafer appeared in the 1950s to describe a thin round slice of semiconductor material, typically germanium or silicon. The round shape characteristic of these wafers comes f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photovoltaic Device
A photovoltaic system, also called a PV system or solar power system, is an electric power system designed to supply usable solar power by means of photovoltaics. It consists of an arrangement of several components, including solar panels to absorb and convert sunlight into electricity, a solar inverter to convert the output from direct current, direct to alternating current, as well as photovoltaic mounting system, mounting, solar cable, cabling, and other electrical accessories to set up a working system. Many utility-scale PV systems use Solar tracker, tracking systems that follow the sun's daily path across the sky to generate more electricity than fixed-mounted systems. Photovoltaic systems convert light directly into electricity and are not to be confused with other solar technologies, such as concentrated solar power or Solar thermal energy, solar thermal, used for heating and cooling. A solar array only encompasses the solar panels, the visible part of the PV system, and d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Vapor Deposition
Chemical vapor deposition (CVD) is a vacuum deposition method used to produce high-quality, and high-performance, solid materials. The process is often used in the semiconductor industry to produce thin films. In typical CVD, the wafer (electronics), wafer (substrate) is exposed to one or more Volatility (chemistry), volatile wikt:precursor, precursors, which chemical reaction, react and/or chemical decomposition, decompose on the substrate surface to produce the desired deposit. Frequently, volatile by-products are also produced, which are removed by gas flow through the reaction chamber. Microfabrication processes widely use CVD to deposit materials in various forms, including: Single crystal, monocrystalline, polycrystalline, amorphous, and Epitaxy, epitaxial. These materials include: silicon (Silicon dioxide, dioxide, silicon carbide, carbide, silicon nitride, nitride, silicon oxynitride, oxynitride), carbon (carbon (fiber), fiber, carbon nanofibers, nanofibers, carbon nanot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrophoricity
A substance is pyrophoric (from , , 'fire-bearing') if it ignites spontaneously in air at or below (for gases) or within 5 minutes after coming into contact with air (for liquids and solids). Examples are organolithium compounds and triethylborane. Pyrophoric materials are often water-reactive as well and will ignite when they contact water or humid air. They can be handled safely in atmospheres of argon or (with a few exceptions) nitrogen. Fire classification fire extinguishers are designated for use in fires involving metals but not pyrophoric materials in general. A related concept is hypergolicity, in which two compounds spontaneously ignite when mixed. Uses The creation of sparks from metals is based on the pyrophoricity of small metal particles, and pyrophoric alloys are made for this purpose. Practical applications include the sparking mechanisms in lighters and various toys, using ferrocerium; starting fires without matches, using a firesteel; the flintlock ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amorphous Silicon
Amorphous silicon (a-Si) is the non-crystalline form of silicon used for solar cells and thin-film transistors in LCDs. Used as semiconductor material for a-Si solar cells, or thin-film silicon solar cells, it is deposited in thin films onto a variety of flexible substrates, such as glass, metal and plastic. Amorphous silicon cells generally feature low efficiency. As a second-generation thin-film solar cell technology, amorphous silicon was once expected to become a major contributor in the fast-growing worldwide photovoltaic market, but has since lost its significance due to strong competition from conventional crystalline silicon cells and other thin-film technologies such as CdTe and CIGS. Amorphous silicon is a preferred material for the thin film transistor (TFT) elements of liquid crystal displays (LCDs) and for x-ray imagers. Amorphous silicon differs from other allotropic variations, such as monocrystalline silicon—a single crystal, and polycrystalline silico ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
