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Alloy-junction Transistor
The germanium alloy-junction transistor, or alloy transistor, was an early type of bipolar junction transistor, developed at General Electric and RCA in 1951 as an improvement over the earlier grown-junction transistor. The usual construction of an alloy-junction transistor is a germanium crystal forming the base, with emitter and collector alloy beads fused on opposite sides. Indium and antimony were commonly used to form the alloy junctions on a bar of N-type germanium. The collector junction pellet would be about 50 mils (thousandths of an inch) in diameter, and the emitter pellet about 20 mils. The base region would be on the order of 1 mil (0.001 inches, 25 μm) thick. There were several types of improved alloy-junction transistors developed over the years that they were manufactured. All types of alloy-junction transistors became obsolete in the early 1960s, with the introduction of the planar transistor which could be mass-produced easily while alloy-junction transisto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2N140 PNP Germanium Alloy Junction Transistor Closeup
N14 may refer to: Roads * N14 road (Belgium), a a national road in Belgium * Route nationale 14, in France * N14 road (Ireland) * N14 expressway (Netherlands) * N14 (South Africa) * A14 motorway (Switzerland) * Nebraska Highway 14, in the United States Vehicles * LNER Class N14, a class of British steam locomotives * Nissan Pulsar (N14), a Japanese automobile * , a submarine of the Royal Navy Other uses * N14 (Long Island bus) * BMW N14, an automobile engine * Flying W Airport in Burlington County, New Jersey, United States * Nitrogen-14, an isotope of nitrogen * N14, a postcode district in the N postcode area The N (Northern) postcode area, also known as the London N postcode area, is the part of the London postal district, London post town covering part of North London, England. It is a group of 25 postcode districts which covers around 17,429 live ... See also * 14N (other) {{Letter-NumberCombDisambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Diffused-base Transistor
A diffused junction transistor is a transistor formed by diffusing dopants into a semiconductor substrate. The diffusion process was developed later than the alloy-junction and grown junction processes for making bipolar junction transistors (BJTs). Bell Labs developed the first prototype diffused junction bipolar transistors in 1954. Diffused-base transistor The earliest diffused junction transistors were diffused-base transistors. These transistors still had alloy emitters and sometimes alloy collectors like the earlier alloy-junction transistors. Only the base was diffused into the substrate. Sometimes the substrate formed the collector, but in transistors like Philco's micro-alloy diffused transistors the substrate was the bulk of the base. Double diffusion At Bell Labs Calvin Souther Fuller produced basic physical understanding of a means of directly forming the emitter, base, and collector by double diffusion. The method was summarized in a history of science at Bell: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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1951 Introductions
Events January * January 4 – Korean War: Third Battle of Seoul – Chinese and North Korean forces capture Seoul for the second time (having lost the Second Battle of Seoul in September 1950). * January 9 – The Government of the United Kingdom announces abandonment of the Tanganyika groundnut scheme for the cultivation of peanuts in the Tanganyika Territory, with the writing off of £36.5M debt. * January 11 – In the U.S., a top secret report is delivered to U.S. President Truman by his National Security Resources Board, urging Truman to expand the Korean War by launching "a global offensive against communism" with sustained bombing of Red China and diplomatic moves to establish "moral justification" for a U.S. nuclear attack on the Soviet Union. The report will not not be declassified until 1978. * January 15 – In a criminal court in West Germany, Ilse Koch, The "Witch of Buchenwald", wife of the commandant of the Buchenwald concentration camp, is sentenced to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrode Transistor
A tetrode transistor is any transistor having four active terminals. Early tetrode transistors There were two types of tetrode transistor developed in the early 1950s as an improvement over the point-contact transistor and the later grown-junction transistor and alloy-junction transistor. Both offered much higher speed than earlier transistors. *Point-contact transistor having two emitters. It became obsolete in the middle 1950s. *Modified grown-junction transistor or alloy-junction transistor having two connections at opposite ends of the base. It achieved its high speed by reducing the input to output capacitance. It became obsolete in the early 1960s with the development of the diffusion transistor. Modern tetrode transistors *Dual-emitter transistor, used in two-input transistor–transistor logic gates *Dual-collector transistor, used in two-output integrated injection logic gates * Diffused planar silicon bipolar junction transistor, - ''Tetrode transistor memory logic cell' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Philips
Koninklijke Philips N.V. (), simply branded Philips, is a Dutch multinational health technology company that was founded in Eindhoven in 1891. Since 1997, its world headquarters have been situated in Amsterdam, though the Benelux headquarters is still in Eindhoven. The company gained its royal honorary title in 1998. Philips was founded by Gerard Philips and his father Frederik, with their first products being light bulbs. Through the 20th century, it grew into one of the world's largest electronics conglomerates, with global market dominance in products ranging from kitchen appliances and electric shavers to light bulbs, televisions, cassettes, and compact discs (both of which were invented by Philips). At one point, it played a dominant role in the entertainment industry (through PolyGram). However, intense competition from primarily East Asian competitors throughout the 1990s and 2000s led to a period of downsizing, including the divestment of its lighting and c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drift-field Transistor
The drift-field transistor, also called the drift transistor or graded base transistor, is a type of high-speed bipolar junction transistor having a doping-engineered electric field in the base to reduce the charge carrier base transit time. Invented by Herbert Kroemer at the Central Bureau of Telecommunications Technology of the German Postal Service, in 1953, it continues to influence the design of modern high-speed bipolar junction transistors. Early drift transistors were made by diffusing the base dopant in a way that caused a higher doping concentration near the emitter reducing towards the collector. This graded base happens automatically with the double diffused planar transistor (so they aren't usually called drift transistors). Similar high speed transistors Another way to speed the base transit time of this type of transistor is to vary the band gap across the base, e.g. in the SiGe pitaxial baseBJT the base of Si1−ηGeη can be grown with η approx 0.2 by the colle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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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] |
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Electric Field
An electric field (sometimes called E-field) is a field (physics), physical field that surrounds electrically charged particles such as electrons. In classical electromagnetism, the electric field of a single charge (or group of charges) describes their capacity to exert attractive or repulsive forces on another charged object. Charged particles exert attractive forces on each other when the sign of their charges are opposite, one being positive while the other is negative, and repel each other when the signs of the charges are the same. Because these forces are exerted mutually, two charges must be present for the forces to take place. These forces are described by Coulomb's law, which says that the greater the magnitude of the charges, the greater the force, and the greater the distance between them, the weaker the force. Informally, the greater the charge of an object, the stronger its electric field. Similarly, an electric field is stronger nearer charged objects and weaker f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Doping (semiconductor)
In semiconductor production, doping is the intentional introduction of impurities into an intrinsic (undoped) semiconductor for the purpose of modulating its electrical, optical and structural properties. The doped material is referred to as an extrinsic semiconductor. Small numbers of dopant atoms can change the ability of a semiconductor to conduct electricity. When on the order of one dopant atom is added per 100 million intrinsic atoms, the doping is said to be ''low'' or ''light''. When many more dopant atoms are added, on the order of one per ten thousand atoms, the doping is referred to as ''high'' or ''heavy''. This is often shown as ''n+'' for n-type doping or ''p+'' for p-type doping. (''See the article on semiconductors for a more detailed description of the doping mechanism.'') A semiconductor doped to such high levels that it acts more like a conductor than a semiconductor is referred to as a degenerate semiconductor. A semiconductor can be considered i-typ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Surface-barrier Transistor
The surface-barrier transistor is a type of transistor developed by Philco in 1953 as an improvement to the alloy-junction transistor and the earlier point-contact transistor. Like the modern Schottky transistor, it offered much higher speed than earlier transistors and used metal–semiconductor junctions (instead of semiconductor–semiconductor junctions), but unlike the Schottky transistor, both junctions were metal–semiconductor junctions. Production process Philco used a patented process of applying two tiny electrochemical jet streams of liquid indium sulfate (electrolyte solution) on opposite sides of a thin strip of N-type germanium base material. This process would etch away and form circular well depressions on each side of the N-type germanium base material, until the germanium base material was ultra thin and having a thickness of approximately a few ten-thousandths of an inch. After the etching process was finished, the polarity applied to the electrolyte was re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2N1307 Transistor Die With Bond Wires Attached
{{Letter-NumberCombDisambig ...
N13 may refer to Roads * N13 road (Ireland) * National Route 13 (Morocco) * Nebraska Highway 13, United States * Route 13 (Laos) * Route nationale 13, France Other uses * Bloomsburg Municipal Airport, in Pennsylvania, United States * BMW N13, an automobile engine * LNER Class N13, a class of British steam locomotives * London Buses route N13 * Nissan Pulsar (N13), an automobile * Nitrogen-13, an isotope of nitrogen * N13, a postcode district in the N postcode area The N (Northern) postcode area, also known as the London N postcode area, is the part of the London postal district, London post town covering part of North London, England. It is a group of 25 postcode districts which covers around 17,429 live ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Philco
Philco (an acronym for Philadelphia Battery Company) is an American electronics industry, electronics manufacturer headquartered in Philadelphia. Philco was a pioneer in battery, radio, and television production. In 1961, the company was purchased by Ford Motor Company, Ford and, from 1966, renamed "Philco-Ford". Ford sold the company to GTE in 1974, and it was purchased by North American Philips, Philips in 1981, which became a subsidiary of the Dutch company Philips in 1987. In North America, the Philco brand is owned by Philips. In other markets, the Philco International brand is owned by Electrolux. In the early 1920s, Philco made storage batteries, "socket power" battery eliminator units (plug-in transformers), and battery chargers. With the invention of the rectifier tube, which made it practical to power radios by electrical outlets, in 1928, Philco entered the radio business. They followed other radio makers such as RCA, Atwater-Kent, Zenith Electronics, Freshman Masterpie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |