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FET
The field-effect transistor (FET) is a type of transistor that uses an electric field to control the current through a semiconductor. It comes in two types: junction FET (JFET) and metal-oxide-semiconductor FET (MOSFET). FETs have three terminals: ''source'', ''gate'', and ''drain''. FETs control the current by the application of a voltage to the gate, which in turn alters the conductivity between the drain and source. FETs are also known as unipolar transistors since they involve single-carrier-type operation. That is, FETs use either electrons (n-channel) or holes (p-channel) as charge carriers in their operation, but not both. Many different types of field effect transistors exist. Field effect transistors generally display very high input impedance at low frequencies. The most widely used field-effect transistor is the MOSFET (metal–oxide–semiconductor field-effect transistor). History The concept of a field-effect transistor (FET) was first patented by the Aust ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MOSFET
upright=1.3, Two power MOSFETs in amperes">A in the ''on'' state, dissipating up to about 100 watt">W and controlling a load of over 2000 W. A matchstick is pictured for scale. In electronics, the metal–oxide–semiconductor field-effect transistor (MOSFET, MOS-FET, MOS FET, or MOS transistor) is a type of field-effect transistor (FET), most commonly fabricated by the controlled oxidation of silicon. It has an insulated gate, the voltage of which determines the conductivity of the device. This ability to change conductivity with the amount of applied voltage can be used for amplifying or switching electronic signals. The term ''metal–insulator–semiconductor field-effect transistor'' (''MISFET'') is almost synonymous with ''MOSFET''. Another near-synonym is ''insulated-gate field-effect transistor'' (''IGFET''). The main advantage of a MOSFET is that it requires almost no input current to control the load current under steady-state or low-frequency conditions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FET Cross Section
The field-effect transistor (FET) is a type of transistor that uses an electric field to control the current through a semiconductor. It comes in two types: junction FET (JFET) and metal-oxide-semiconductor FET (MOSFET). FETs have three terminals: ''source'', ''gate'', and ''drain''. FETs control the current by the application of a voltage to the gate, which in turn alters the conductivity between the drain and source. FETs are also known as unipolar transistors since they involve single-carrier-type operation. That is, FETs use either electrons (n-channel) or holes (p-channel) as charge carriers in their operation, but not both. Many different types of field effect transistors exist. Field effect transistors generally display very high input impedance at low frequencies. The most widely used field-effect transistor is the MOSFET (metal–oxide–semiconductor field-effect transistor). History The concept of a field-effect transistor (FET) was first patented by the Aust ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transistor
A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch electrical signals and electric power, power. It is one of the basic building blocks of modern electronics. It is composed of semiconductor material, usually with at least three terminal (electronics), terminals for connection to an electronic circuit. A voltage or Electric current, current applied to one pair of the transistor's terminals controls the current through another pair of terminals. Because the controlled (output) power can be higher than the controlling (input) power, a transistor can amplify a signal. Some transistors are packaged individually, but many more in miniature form are found embedded in integrated circuits. Because transistors are the key active components in practically all modern electronics, many people consider them one of the 20th century's greatest inventions. Physicist Julius Edgar Lilienfeld proposed the concept of a field-effect transisto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JFET
The junction field-effect transistor (JFET) is one of the simplest types of field-effect transistor. JFETs are three-terminal semiconductor devices that can be used as electronically controlled switches or resistors, or to build amplifiers. Unlike bipolar junction transistors, JFETs are exclusively voltage-controlled in that they do not need a biasing current. Electric charge flows through a semiconducting channel between ''source'' and ''drain'' terminals. By applying a reverse bias voltage to a ''gate'' terminal, the channel is '' pinched'', so that the electric current is impeded or switched off completely. A JFET is usually conducting when there is zero voltage between its gate and source terminals. If a potential difference of the proper polarity is applied between its gate and source terminals, the JFET will be more resistive to current flow, which means less current would flow in the channel between the source and drain terminals. JFETs are sometimes referred to a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semiconductor Device
A semiconductor device is an electronic component that relies on the electronic properties of a semiconductor material (primarily silicon, germanium, and gallium arsenide, as well as organic semiconductors) for its function. Its conductivity lies between conductors and insulators. Semiconductor devices have replaced vacuum tubes in most applications. They conduct electric current in the solid state, rather than as free electrons across a vacuum (typically liberated by thermionic emission) or as free electrons and ions through an ionized gas. Semiconductor devices are manufactured both as single discrete devices and as integrated circuit (IC) chips, which consist of two or more devices—which can number from the hundreds to the billions—manufactured and interconnected on a single semiconductor wafer (also called a substrate). Semiconductor materials are useful because their behavior can be easily manipulated by the deliberate addition of impurities, known as dopin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Static Induction Transistor
The static induction transistor (SIT) is a type of field-effect transistor (FET) capable of high-speed and high-power operation, with low distortion and low noise. It is a vertical structure device with short multichannel. The device was originally known as a VFET, with V being short for vertical. Being a vertical device, the SIT structure offers advantages in obtaining higher breakdown voltages than a conventional FET. For the SIT, the breakdown voltage is not limited by the surface breakdown between gate and drain, allowing it to operate at a very high current and voltage. The SIT has a current-voltage characteristic similar to a vacuum tube triode and it was therefore used in high-end audio products, including power amplifiers from Sony is a Japanese multinational conglomerate (company), conglomerate headquartered at Sony City in Minato, Tokyo, Japan. The Sony Group encompasses various businesses, including Sony Corporation (electronics), Sony Semiconductor Solutio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charge Carrier
In solid state physics, a charge carrier is a particle or quasiparticle that is free to move, carrying an electric charge, especially the particles that carry electric charges in electrical conductors. Examples are electrons, ions and holes. In a conducting medium, an electric field can exert force on these free particles, causing a net motion of the particles through the medium; this is what constitutes an electric current. The electron and the proton are the elementary charge carriers, each carrying one elementary charge (''e''), of the same magnitude and opposite sign. In conductors In conducting mediums, particles serve to carry charge. In many metals, the charge carriers are electrons. One or two of the valence electrons from each atom are able to move about freely within the crystal structure of the metal. The free electrons are referred to as conduction electrons, and the cloud of free electrons is called a Fermi gas. Many metals have electron and hole bands. In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bipolar Junction Transistor
A bipolar junction transistor (BJT) is a type of transistor that uses both electrons and electron holes as charge carriers. In contrast, a unipolar transistor, such as a field-effect transistor (FET), uses only one kind of charge carrier. A bipolar transistor allows a small current injected at one of its terminals to control a much larger current between the remaining two terminals, making the device capable of amplification or switching. BJTs use two p–n junctions between two semiconductor types, n-type and p-type, which are regions in a single crystal of material. The junctions can be made in several different ways, such as changing the doping of the semiconductor material as it is grown, by depositing metal pellets to form alloy junctions, or by such methods as diffusion of n-type and p-type doping substances into the crystal. The superior predictability and performance of junction transistors quickly displaced the original point-contact transistor. Diffused trans ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oskar Heil
Oskar Heil (20 March 1908, in Langwieden – 15 May 1994, San Mateo, California) was a German electrical engineer and inventor. He studied physics, chemistry, mathematics, and music at the Georg-August University of Göttingen and was awarded his PhD in 1933, for his work on molecular spectroscopy. Personal life At the Georg-August University in Göttingen, Oskar Heil met Agnesa Arsenjewa (Агнесса Николаевна Арсеньева, 1901–1991), a promising young Russian physicist who also earned her PhD there. They married in Leningrad, the Soviet Union in 1934. Together they moved to the United Kingdom to work in the Cavendish Laboratory, University of Cambridge. While on a trip to Italy, they co-wrote a pioneering paper on the generation of microwaves which was published in Germany in the ''Zeitschrift für Physik'' (i.e., ''Journal on Physics'') in 1935. Agnesa subsequently returned to Russia to pursue this work further at the Leningrad Physico-Chemical Insti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Julius Edgar Lilienfeld (1881-1963)
Julius Edgar Lilienfeld (April 18, 1882 – August 28, 1963) was an American electrical engineer and physicist who has been credited with the first patent on the field-effect transistor in 1925. He was never able to build a working practical semiconductor device based on his concept. Additionally, because he didn't publish articles in learned journals and since high-purity semiconductor materials were not available to him, his FET patent never achieved fame, causing confusion for later inventors. Early life Lilienfeld was born to a Jewish family in Lemberg (present-day Lviv) in the Austrian part of the Austro-Hungarian Empire. Lilienfeld's father was the lawyer Sigmund Lilienfeld, his mother Sarah Jampoler Lilienfeld. Education After graduating high school in 1899, between 1900 and 1904, Lilienfeld studied at the Friedrich-Wilhelms-Universität (renamed Humboldt University in 1949), in Berlin, where he received his Ph.D. on February 18, 1905. In 1905, he started work at the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heinrich Welker
Heinrich Johann Welker (9 September 1912 in Ingolstadt – 25 December 1981 in Erlangen) was a German theoretical and applied physicist who invented the " transistron", a transistor made at Westinghouse independently of the first successful transistor made at Bell Laboratories. He did fundamental work in III-V compound semiconductors, and paved the way for microwave semiconductor elements and laser diodes. Biography and important work Starting in 1931, Welker studied at the University of Munich under Arnold Sommerfeld, and was granted a Ph.D. in 1936. The book '' Electrodynamics - Lectures on Theoretical Physics Volume III'' by Sommerfeld was based on lecture notes prepared by Welker during the winter semester of 1933/1934. Welker was granted his Habilitation under Sommerfeld in 1939.Mehra, Volume 6, Part 2, 2001, p. 868. During the war years, 1940 to 1945, Welker worked at Luftfunkforschungs Institut in Oberpfaffenhofen, but still maintained association (1942 to 1944) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
