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Silicon carbide (SiC), also known as carborundum (/ ˌ k ɑːr b ə ˈ r ʌ n d əm /), is a hard chemical compound containing silicon and carbon. A wide bandgap semiconductor , it occurs in nature as the extremely rare mineral moissanite , but has been mass-produced as a powder and crystal since 1893 for use as an abrasive .
In these fragments he discovered minute quantities of a new mineral and, after extensive research, Moissan concluded that this mineral was made of silicon carbide. In 1905, this mineral was named moissanite, in his honor. In 1903 Moissan was elected member of the International Atomic Weights Committee where he served until his death. [18]
Moissanite (/ ˈ m ɔɪ s ə ˌ n aɪ t /) [5] is naturally occurring silicon carbide and its various crystalline polymorphs.It has the chemical formula SiC and is a rare mineral, discovered by the French chemist Henri Moissan in 1893.
He found that the silicon vaporized when overheated, leaving graphite. He also discovered that when starting with carbon instead of silicon carbide, graphite was produced only when there was an impurity, such as silica, that would result in first producing a carbide. He patented the process of making graphite in 1896. [5]
Recreation of the 1907 experiment by H. J. Round on the observation of electroluminescence from a point contact with a carborundum (silicon carbide) crystalIn some later experiments with cat's whisker detectors using a variety of substances, he passed current through them and noticed that some gave off light – the first known report of the effect of the light-emitting diode (LED).
Silicon carbide is a semiconductor with a wide band gap of 3 eV, so to make the detector more sensitive a forward bias voltage of several volts was usually applied across the junction by a battery and potentiometer. [19] [23] [33] [32] The voltage was adjusted with the potentiometer until the sound was loudest in the earphone.
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The first Light-Emitting Diode was created in 1927 by Russian inventor Oleg Losev, [1] and used silicon carbide as a semiconductor. However, electroluminescence as a phenomenon was discovered twenty years earlier by the English experimenter Henry Joseph Round of Marconi Labs, using the same crystal and a cat's-whisker detector.