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77-565: The radiation-hardening of the original RSC 1.1 million- transistor processor to make the RAD6000's CPU was done by IBM Federal Systems Division working with the Air Force Research Laboratory . As of June 2008, there are 200 RAD6000 processors in space on a variety of NASA, United States Department of Defense and commercial spacecraft, including: The computer has a maximum clock rate of 33  MHz and

154-499: A v ) A 0 {\displaystyle A_{\mathrm {G} }=\lambda _{\mathrm {B} }(1-r_{\mathrm {av} })A_{0}} . Experimental values for the "generalized" coefficient A G are generally of the order of magnitude of A 0 , but do differ significantly as between different emitting materials, and can differ as between different crystallographic faces of the same material. At least qualitatively, these experimental differences can be explained as due to differences in

231-501: A field-effect transistor , or may have two kinds of charge carriers in bipolar junction transistor devices. Compared with the vacuum tube , transistors are generally smaller and require less power to operate. Certain vacuum tubes have advantages over transistors at very high operating frequencies or high operating voltages, such as Traveling-wave tubes and Gyrotrons . Many types of transistors are made to standardized specifications by multiple manufacturers. The thermionic triode ,

308-474: A hot cathode into an enclosed vacuum and may steer those emitted electrons with applied voltage . The hot cathode can be a metal filament, a coated metal filament, or a separate structure of metal or carbides or borides of transition metals . Vacuum emission from metals tends to become significant only for temperatures over 1,000  K (730  °C ; 1,340  °F ). Charge flow increases dramatically with temperature. The term thermionic emission

385-532: A p-n-p transistor symbol, the arrow " P oints i N P roudly". However, this does not apply to MOSFET-based transistor symbols as the arrow is typically reversed (i.e. the arrow for the n-p-n points inside). The field-effect transistor , sometimes called a unipolar transistor , uses either electrons (in n-channel FET ) or holes (in p-channel FET ) for conduction. The four terminals of the FET are named source , gate , drain , and body ( substrate ). On most FETs,

462-476: A vacuum tube invented in 1907, enabled amplified radio technology and long-distance telephony . The triode, however, was a fragile device that consumed a substantial amount of power. In 1909, physicist William Eccles discovered the crystal diode oscillator . Physicist Julius Edgar Lilienfeld filed a patent for a field-effect transistor (FET) in Canada in 1925, intended as a solid-state replacement for

539-431: A decrease of collector emitting work function from 1.5 eV to 1.0–0.7 eV. Due to long-lived nature of Rydberg matter this low work function remains low which essentially increases the low-temperature converter's efficiency. Photon-enhanced thermionic emission (PETE) is a process developed by scientists at Stanford University that harnesses both the light and heat of the sun to generate electricity and increases

616-578: A device had been built. In 1934, inventor Oskar Heil patented a similar device in Europe. From November 17 to December 23, 1947, John Bardeen and Walter Brattain at AT&T 's Bell Labs in Murray Hill, New Jersey , performed experiments and observed that when two gold point contacts were applied to a crystal of germanium , a signal was produced with the output power greater than the input. Solid State Physics Group leader William Shockley saw

693-600: A few hundred milliwatts, but power and audio fidelity gradually increased as better transistors became available and amplifier architecture evolved. Modern transistor audio amplifiers of up to a few hundred watts are common and relatively inexpensive. Before transistors were developed, vacuum (electron) tubes (or in the UK "thermionic valves" or just "valves") were the main active components in electronic equipment. The key advantages that have allowed transistors to replace vacuum tubes in most applications are Transistors may have

770-425: A field-effect transistor (FET) by trying to modulate the conductivity of a semiconductor, but was unsuccessful, mainly due to problems with the surface states , the dangling bond , and the germanium and copper compound materials. Trying to understand the mysterious reasons behind this failure led them instead to invent the bipolar point-contact and junction transistors . In 1948, the point-contact transistor

847-412: A particular type, varies depending on the collector current. In the example of a light-switch circuit, as shown, the resistor is chosen to provide enough base current to ensure the transistor is saturated. The base resistor value is calculated from the supply voltage, transistor C-E junction voltage drop, collector current, and amplification factor beta. The common-emitter amplifier is designed so that

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924-479: A processing speed of about 35  MIPS . In addition to the CPU itself, the RAD6000 has 128  MB of ECC RAM . A typical real-time operating system running on NASA's RAD6000 installations is VxWorks . The Flight boards in the above systems have switchable clock rates of 2.5, 5, 10, or 20 MHz. Reported to have a unit cost somewhere between US$ 200,000 and US$ 300,000, RAD6000 computers were released for sale in

1001-467: A silicon MOS transistor in 1959 and successfully demonstrated a working MOS device with their Bell Labs team in 1960. Their team included E. E. LaBate and E. I. Povilonis who fabricated the device; M. O. Thurston, L. A. D’Asaro, and J. R. Ligenza who developed the diffusion processes, and H. K. Gummel and R. Lindner who characterized the device. With its high scalability , much lower power consumption, and higher density than bipolar junction transistors,

1078-605: A small change in voltage ( V in ) changes the small current through the base of the transistor whose current amplification combined with the properties of the circuit means that small swings in V in produce large changes in V out . Various configurations of single transistor amplifiers are possible, with some providing current gain, some voltage gain, and some both. From mobile phones to televisions , vast numbers of products include amplifiers for sound reproduction , radio transmission , and signal processing . The first discrete-transistor audio amplifiers barely supplied

1155-418: A solid that are free to move from atom to atom. This is sometimes collectively referred to as a "sea of electrons". Their velocities follow a statistical distribution, rather than being uniform, and occasionally an electron will have enough velocity to exit the metal without being pulled back in. The minimum amount of energy needed for an electron to leave a surface is called the work function . The work function

1232-539: A type of heat engine . Following J. J. Thomson's identification of the electron in 1897, the British physicist Owen Willans Richardson began work on the topic that he later called "thermionic emission". He received a Nobel Prize in Physics in 1928 "for his work on the thermionic phenomenon and especially for the discovery of the law named after him". From band theory , there are one or two electrons per atom in

1309-440: A type of 3D non-planar multi-gate MOSFET, originated from the research of Digh Hisamoto and his team at Hitachi Central Research Laboratory in 1989. Because transistors are the key active components in practically all modern electronics , many people consider them one of the 20th century's greatest inventions. The invention of the first transistor at Bell Labs was named an IEEE Milestone in 2009. Other Milestones include

1386-416: A weaker input signal, acting as an amplifier . It can also be used as an electrically controlled switch , where the amount of current is determined by other circuit elements. There are two types of transistors, with slight differences in how they are used: The top image in this section represents a typical bipolar transistor in a circuit. A charge flows between emitter and collector terminals depending on

1463-461: A working bipolar NPN junction amplifying germanium transistor. Bell announced the discovery of this new "sandwich" transistor in a press release on July 4, 1951. The first high-frequency transistor was the surface-barrier germanium transistor developed by Philco in 1953, capable of operating at frequencies up to 60 MHz . They were made by etching depressions into an n-type germanium base from both sides with jets of indium(III) sulfate until it

1540-409: Is characteristic of the material and for most metals is on the order of several electronvolts (eV). Thermionic currents can be increased by decreasing the work function. This often-desired goal can be achieved by applying various oxide coatings to the wire. In 1901 Richardson published the results of his experiments: the current from a heated wire seemed to depend exponentially on the temperature of

1617-414: Is less than W . (For essentially every material, melting occurs well before kT = W .) The thermionic emission law has been recently revised for 2D materials in various models. In electron emission devices, especially electron guns , the thermionic electron emitter will be biased negative relative to its surroundings. This creates an electric field of magnitude E at the emitter surface. Without

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1694-481: Is not observed in modern devices, for example, at the 65 nm technology node. For low noise at narrow bandwidth , the higher input resistance of the FET is advantageous. FETs are divided into two families: junction FET ( JFET ) and insulated gate FET (IGFET). The IGFET is more commonly known as a metal–oxide–semiconductor FET ( MOSFET ), reflecting its original construction from layers of metal (the gate), oxide (the insulation), and semiconductor. Unlike IGFETs,

1771-442: Is now also used to refer to any thermally-excited charge emission process, even when the charge is emitted from one solid-state region into another. Because the electron was not identified as a separate physical particle until the work of J. J. Thomson in 1897, the word "electron" was not used when discussing experiments that took place before this date. The phenomenon was initially reported in 1853 by Edmond Becquerel . It

1848-421: Is often easier and cheaper to use a standard microcontroller and write a computer program to carry out a control function than to design an equivalent mechanical system. A transistor can use a small signal applied between one pair of its terminals to control a much larger signal at another pair of terminals, a property called gain . It can produce a stronger output signal, a voltage or current, proportional to

1925-441: Is still no consensus among interested theoreticians as to the exact expression of A G , but there is agreement that A G must be written in the form: where λ R is a material-specific correction factor that is typically of order 0.5, and A 0 is a universal constant given by where m {\displaystyle m} and − q e {\displaystyle -q_{\text{e}}} are

2002-549: Is the metal–oxide–semiconductor field-effect transistor (MOSFET), the MOSFET was invented at Bell Labs between 1955 and 1960. Transistors revolutionized the field of electronics and paved the way for smaller and cheaper radios , calculators , computers , and other electronic devices. Most transistors are made from very pure silicon , and some from germanium , but certain other semiconductor materials are sometimes used. A transistor may have only one kind of charge carrier in

2079-478: Is the liberation of charged particles from a hot electrode whose thermal energy gives some particles enough kinetic energy to escape the material's surface. The particles, sometimes called thermions in early literature, are now known to be ions or electrons . Thermal electron emission specifically refers to emission of electrons and occurs when thermal energy overcomes the material's work function . After emission, an opposite charge of equal magnitude to

2156-399: The surface state barrier that prevented the external electric field from penetrating the material. In 1955, Carl Frosch and Lincoln Derick accidentally grew a layer of silicon dioxide over the silicon wafer, for which they observed surface passivation effects. By 1957 Frosch and Derick, using masking and predeposition, were able to manufacture silicon dioxide field effect transistors;

2233-487: The 20th century's greatest inventions. Physicist Julius Edgar Lilienfeld proposed the concept of a field-effect transistor (FET) in 1926, but it was not possible to construct a working device at that time. The first working device was a point-contact transistor invented in 1947 by physicists John Bardeen , Walter Brattain , and William Shockley at Bell Labs who shared the 1956 Nobel Prize in Physics for their achievement. The most widely used type of transistor

2310-608: The British Wireless Telegraphy Company , discovered that the Edison effect could be used to detect radio waves . Fleming went on to develop a two-element thermionic vacuum tube diode called the Fleming valve (patented 16 November 1904). Thermionic diodes can also be configured to convert a heat difference to electric power directly without moving parts as a device called a thermionic converter ,

2387-511: The JFET gate forms a p–n diode with the channel which lies between the source and drains. Functionally, this makes the n-channel JFET the solid-state equivalent of the vacuum tube triode which, similarly, forms a diode between its grid and cathode . Also, both devices operate in the depletion-mode , they both have a high input impedance, and they both conduct current under the control of an input voltage. Thermionic Thermionic emission

IBM RAD6000 - Misplaced Pages Continue

2464-412: The MOSFET made it possible to build high-density integrated circuits, allowing the integration of more than 10,000 transistors in a single IC. Bardeen and Brattain's 1948 inversion layer concept forms the basis of CMOS technology today. The CMOS (complementary MOS ) was invented by Chih-Tang Sah and Frank Wanlass at Fairchild Semiconductor in 1963. The first report of a floating-gate MOSFET

2541-775: The Regency Division of Industrial Development Engineering Associates, I.D.E.A. and Texas Instruments of Dallas, Texas, the TR-1 was manufactured in Indianapolis, Indiana. It was a near pocket-sized radio with four transistors and one germanium diode. The industrial design was outsourced to the Chicago firm of Painter, Teague and Petertil. It was initially released in one of six colours: black, ivory, mandarin red, cloud grey, mahogany and olive green. Other colours shortly followed. The first production all-transistor car radio

2618-431: The basis of modern digital electronics since the late 20th century, paving the way for the digital age . The US Patent and Trademark Office calls it a "groundbreaking invention that transformed life and culture around the world". Its ability to be mass-produced by a highly automated process ( semiconductor device fabrication ), from relatively basic materials, allows astonishingly low per-transistor costs. MOSFETs are

2695-404: The body is connected to the source inside the package, and this will be assumed for the following description. In a FET, the drain-to-source current flows via a conducting channel that connects the source region to the drain region. The conductivity is varied by the electric field that is produced when a voltage is applied between the gate and source terminals, hence the current flowing between

2772-437: The collector to the emitter. If the voltage difference between the collector and emitter were zero (or near zero), the collector current would be limited only by the load resistance (light bulb) and the supply voltage. This is called saturation because the current is flowing from collector to emitter freely. When saturated, the switch is said to be on . The use of bipolar transistors for switching applications requires biasing

2849-601: The combined effects of field-enhanced thermionic and field emission can be modeled by the Murphy-Good equation for thermo-field (T-F) emission. At even higher fields, FN tunneling becomes the dominant electron emission mechanism, and the emitter operates in the so-called "cold field electron emission (CFE)" regime. Thermionic emission can also be enhanced by interaction with other forms of excitation such as light. For example, excited Cesium (Cs) vapors in thermionic converters form clusters of Cs- Rydberg matter which yield

2926-445: The concept of an inversion layer, forms the basis of CMOS and DRAM technology today. In the early years of the semiconductor industry , companies focused on the junction transistor , a relatively bulky device that was difficult to mass-produce , limiting it to several specialized applications. Field-effect transistors (FETs) were theorized as potential alternatives, but researchers could not get them to work properly, largely due to

3003-470: The current as the Edison effect , though it wasn't until after the 1897 discovery of the electron that scientists understood that electrons were emitted and why. Thermionic emission is crucial to the operation of a variety of electronic devices and can be used for electricity generation (such as thermionic converters and electrodynamic tethers ) or cooling. Thermionic vacuum tubes emit electrons from

3080-559: The current in the base. Because the base and emitter connections behave like a semiconductor diode, a voltage drop develops between them. The amount of this drop, determined by the transistor's material, is referred to as V BE . (Base Emitter Voltage) Transistors are commonly used in digital circuits as electronic switches which can be either in an "on" or "off" state, both for high-power applications such as switched-mode power supplies and for low-power applications such as logic gates . Important parameters for this application include

3157-456: The current switched, the voltage handled, and the switching speed, characterized by the rise and fall times . In a switching circuit, the goal is to simulate, as near as possible, the ideal switch having the properties of an open circuit when off, the short circuit when on, and an instantaneous transition between the two states. Parameters are chosen such that the "off" output is limited to leakage currents too small to affect connected circuitry,

IBM RAD6000 - Misplaced Pages Continue

3234-628: The device to operate a telegraph sounder, which was exhibited at the International Electrical Exhibition of 1884 in Philadelphia. Visiting British scientist William Preece received several bulbs from Edison to investigate. Preece's 1885 paper on them referred to the one-way current through the partial vacuum as the Edison effect, although that term is occasionally used to refer to thermionic emission itself. British physicist John Ambrose Fleming , working for

3311-460: The drain and source is controlled by the voltage applied between the gate and source. As the gate–source voltage ( V GS ) is increased, the drain–source current ( I DS ) increases exponentially for V GS below threshold, and then at a roughly quadratic rate: ( I DS ∝ ( V GS − V T ) , where V T is the threshold voltage at which drain current begins) in the " space-charge-limited " region above threshold. A quadratic behavior

3388-436: The efficiency of solar power production by more than twice the current levels. The device developed for the process reaches peak efficiency above 200 °C, while most silicon solar cells become inert after reaching 100 °C. Such devices work best in parabolic dish collectors, which reach temperatures up to 800 °C. Although the team used a gallium nitride semiconductor in its proof-of-concept device, it claims that

3465-464: The emitted charge is initially left behind in the emitting region. But if the emitter is connected to a battery , that remaining charge is neutralized by charge supplied by the battery as particles are emitted, so the emitter will have the same charge it had before emission. This facilitates additional emission to sustain an electric current . Thomas Edison in 1880 while inventing his light bulb noticed this current, so subsequent scientists referred to

3542-512: The equation where ε 0 is the electric constant (also called the vacuum permittivity ). Electron emission that takes place in the field-and-temperature-regime where this modified equation applies is often called Schottky emission . This equation is relatively accurate for electric field strengths lower than about 10  V⋅m . For electric field strengths higher than 10  V⋅m , so-called Fowler–Nordheim (FN) tunneling begins to contribute significant emission current. In this regime,

3619-572: The field, the surface barrier seen by an escaping Fermi-level electron has height W equal to the local work-function. The electric field lowers the surface barrier by an amount Δ W , and increases the emission current. This is known as the Schottky effect (named for Walter H. Schottky ) or field enhanced thermionic emission. It can be modeled by a simple modification of the Richardson equation, by replacing W by ( W  − Δ W ). This gives

3696-463: The first planar transistors, in which drain and source were adjacent at the same surface. They showed that silicon dioxide insulated, protected silicon wafers and prevented dopants from diffusing into the wafer. After this, J.R. Ligenza and W.G. Spitzer studied the mechanism of thermally grown oxides, fabricated a high quality Si/ SiO 2 stack and published their results in 1960. Following this research, Mohamed Atalla and Dawon Kahng proposed

3773-454: The following limitations: Transistors are categorized by Hence, a particular transistor may be described as silicon, surface-mount, BJT, NPN, low-power, high-frequency switch . Convenient mnemonic to remember the type of transistor (represented by an electrical symbol ) involves the direction of the arrow. For the BJT , on an n-p-n transistor symbol, the arrow will " N ot P oint i N" . On

3850-544: The general commercial market in 1996. The RAD6000's successor is the RAD750 processor, based on IBM's PowerPC 750 . Transistor A transistor is a semiconductor device used to amplify or switch electrical signals and power . It is one of the basic building blocks of modern electronics . It is composed of semiconductor material , usually with at least three terminals for connection to an electronic circuit . A voltage or current applied to one pair of

3927-477: The glass, Edison did a series of experiments (a first inconclusive one is in his notebook on 13 February 1880) such as the following successful one: This effect had many applications. Edison found that the current emitted by the hot filament increased rapidly with voltage , and filed a patent for a voltage-regulating device using the effect on 15 November 1883, notably the first US patent for an electronic device. He found that sufficient current would pass through

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4004-450: The idea of a field-effect transistor that used an electric field as a "grid" was not new. Instead, what Bardeen, Brattain, and Shockley invented in 1947 was the first point-contact transistor . To acknowledge this accomplishment, Shockley, Bardeen and Brattain jointly received the 1956 Nobel Prize in Physics "for their researches on semiconductors and their discovery of the transistor effect". Shockley's team initially attempted to build

4081-418: The inventions of the junction transistor in 1948 and the MOSFET in 1959. The MOSFET is by far the most widely used transistor, in applications ranging from computers and electronics to communications technology such as smartphones . It has been considered the most important transistor, possibly the most important invention in electronics, and the device that enabled modern electronics. It has been

4158-421: The literature, the elementary equation is sometimes given in circumstances where the generalized equation would be more appropriate, and this in itself can cause confusion. To avoid misunderstandings, the meaning of any "A-like" symbol should always be explicitly defined in terms of the more fundamental quantities involved. Because of the exponential function, the current increases rapidly with temperature when kT

4235-454: The mass and charge of an electron, respectively, and h {\displaystyle h} is the Planck constant . In fact, by about 1930 there was agreement that, due to the wave-like nature of electrons, some proportion r av of the outgoing electrons would be reflected as they reached the emitter surface, so the emission current density would be reduced, and λ R would have

4312-613: The mechanical encoding from punched metal cards. The first prototype pocket transistor radio was shown by INTERMETALL, a company founded by Herbert Mataré in 1952, at the Internationale Funkausstellung Düsseldorf from August 29 to September 6, 1953. The first production-model pocket transistor radio was the Regency TR-1 , released in October 1954. Produced as a joint venture between

4389-484: The metal, k is the Boltzmann constant , and A G is a parameter discussed next. In the period 1911 to 1930, as physical understanding of the behaviour of electrons in metals increased, various theoretical expressions (based on different physical assumptions) were put forward for A G , by Richardson, Saul Dushman , Ralph H. Fowler , Arnold Sommerfeld and Lothar Wolfgang Nordheim . Over 60 years later, there

4466-927: The most numerously produced artificial objects in history, with more than 13 sextillion manufactured by 2018. Although several companies each produce over a billion individually packaged (known as discrete ) MOS transistors every year, the vast majority are produced in integrated circuits (also known as ICs , microchips, or simply chips ), along with diodes , resistors , capacitors and other electronic components , to produce complete electronic circuits. A logic gate consists of up to about 20 transistors, whereas an advanced microprocessor , as of 2022, may contain as many as 57 billion MOSFETs. Transistors are often organized into logic gates in microprocessors to perform computation. The transistor's low cost, flexibility and reliability have made it ubiquitous. Transistorized mechatronic circuits have replaced electromechanical devices in controlling appliances and machinery. It

4543-459: The negative end and was attracted towards and sometimes absorbed by the positive end of the filament loop. This projected carbon was deemed "electrical carrying" and initially ascribed to an effect in Crookes tubes where negatively-charged cathode rays from ionized gas move from a negative to a positive electrode. To try to redirect the charged carbon particles to a separate electrode instead of

4620-548: The potential in this, and over the next few months worked to greatly expand the knowledge of semiconductors . The term transistor was coined by John R. Pierce as a contraction of the term transresistance . According to Lillian Hoddeson and Vicki Daitch, Shockley proposed that Bell Labs' first patent for a transistor should be based on the field-effect and that he be named as the inventor. Having unearthed Lilienfeld's patents that went into obscurity years earlier, lawyers at Bell Labs advised against Shockley's proposal because

4697-405: The resistance of the transistor in the "on" state is too small to affect circuitry, and the transition between the two states is fast enough not to have a detrimental effect. In a grounded-emitter transistor circuit, such as the light-switch circuit shown, as the base voltage rises, the emitter and collector currents rise exponentially. The collector voltage drops because of reduced resistance from

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4774-409: The transistor so that it operates between its cut-off region in the off-state and the saturation region ( on ). This requires sufficient base drive current. As the transistor provides current gain, it facilitates the switching of a relatively large current in the collector by a much smaller current into the base terminal. The ratio of these currents varies depending on the type of transistor, and even for

4851-450: 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

4928-483: The transistor, the company rushed to get its "transistron" into production for amplified use in France's telephone network, filing his first transistor patent application on August 13, 1948. The first bipolar junction transistors were invented by Bell Labs' William Shockley, who applied for patent (2,569,347) on June 26, 1948. On April 12, 1950, Bell Labs chemists Gordon Teal and Morgan Sparks successfully produced

5005-486: The triode. He filed identical patents in the United States in 1926 and 1928. However, he did not publish any research articles about his devices nor did his patents cite any specific examples of a working prototype. Because the production of high-quality semiconductor materials was still decades away, Lilienfeld's solid-state amplifier ideas would not have found practical use in the 1920s and 1930s, even if such

5082-424: The value 1 − r av . Thus, one sometimes sees the thermionic emission equation written in the form: However, a modern theoretical treatment by Modinos assumes that the band-structure of the emitting material must also be taken into account. This would introduce a second correction factor λ B into λ R , giving A G = λ B ( 1 − r

5159-544: The value of λ R . Considerable confusion exists in the literature of this area because: (1) many sources do not distinguish between A G and A 0 , but just use the symbol A (and sometimes the name "Richardson constant") indiscriminately; (2) equations with and without the correction factor here denoted by λ R are both given the same name; and (3) a variety of names exist for these equations, including "Richardson equation", "Dushman's equation", "Richardson–Dushman equation" and "Richardson–Laue–Dushman equation". In

5236-408: The widespread adoption of transistor radios. Seven million TR-63s were sold worldwide by the mid-1960s. Sony's success with transistor radios led to transistors replacing vacuum tubes as the dominant electronic technology in the late 1950s. The first working silicon transistor was developed at Bell Labs on January 26, 1954, by Morris Tanenbaum . The first production commercial silicon transistor

5313-418: The wire with a mathematical form similar to the modified Arrhenius equation , T 1 / 2 e − b / T {\displaystyle T^{1/2}\mathrm {e} ^{-b/T}} . Later, he proposed that the emission law should have the mathematical form where J is the emission current density , T is the temperature of the metal, W is the work function of

5390-525: Was a few ten-thousandths of an inch thick. Indium electroplated into the depressions formed the collector and emitter. AT&T first used transistors in telecommunications equipment in the No. 4A Toll Crossbar Switching System in 1953, for selecting trunk circuits from routing information encoded on translator cards. Its predecessor, the Western Electric No. 3A phototransistor , read

5467-486: Was announced by Texas Instruments in May 1954. This was the work of Gordon Teal , an expert in growing crystals of high purity, who had previously worked at Bell Labs. The basic principle of the field-effect transistor (FET) was first proposed by physicist Julius Edgar Lilienfeld when he filed a patent for a device similar to MESFET in 1926, and for an insulated-gate field-effect transistor in 1928. The FET concept

5544-521: Was developed by Chrysler and Philco corporations and was announced in the April 28, 1955, edition of The Wall Street Journal . Chrysler made the Mopar model 914HR available as an option starting in fall 1955 for its new line of 1956 Chrysler and Imperial cars, which reached dealership showrooms on October 21, 1955. The Sony TR-63, released in 1957, was the first mass-produced transistor radio, leading to

5621-918: Was independently invented by physicists Herbert Mataré and Heinrich Welker while working at the Compagnie des Freins et Signaux Westinghouse , a Westinghouse subsidiary in Paris . Mataré had previous experience in developing crystal rectifiers from silicon and germanium in the German radar effort during World War II . With this knowledge, he began researching the phenomenon of "interference" in 1947. By June 1948, witnessing currents flowing through point-contacts, he produced consistent results using samples of germanium produced by Welker, similar to what Bardeen and Brattain had accomplished earlier in December 1947. Realizing that Bell Labs' scientists had already invented

5698-455: Was later also theorized by engineer Oskar Heil in the 1930s and by William Shockley in the 1940s. In 1945 JFET was patented by Heinrich Welker . Following Shockley's theoretical treatment on JFET in 1952, a working practical JFET was made in 1953 by George C. Dacey and Ian M. Ross . In 1948, Bardeen and Brattain patented the progenitor of MOSFET at Bell Labs, an insulated-gate FET (IGFET) with an inversion layer. Bardeen's patent, and

5775-521: Was made by Dawon Kahng and Simon Sze in 1967. In 1967, Bell Labs researchers Robert Kerwin, Donald Klein and John Sarace developed the self-aligned gate (silicon-gate) MOS transistor, which Fairchild Semiconductor researchers Federico Faggin and Tom Klein used to develop the first silicon-gate MOS integrated circuit . A double-gate MOSFET was first demonstrated in 1984 by Electrotechnical Laboratory researchers Toshihiro Sekigawa and Yutaka Hayashi. The FinFET (fin field-effect transistor),

5852-448: Was observed again by Thomas Edison in 1880 while his team was trying to discover the reason for breakage of carbonized bamboo filaments and undesired blackening of the interior surface of the bulbs in his incandescent lamps . This blackening was carbon deposited from the filament and was darkest near the positive end of the filament loop, which apparently cast a light shadow on the glass, as if negatively-charged carbon emanated from

5929-554: Was observed again in 1873 by Frederick Guthrie in Britain. While doing work on charged objects, Guthrie discovered that a red-hot iron sphere with a negative charge would lose its charge (by somehow discharging it into air). He also found that this did not happen if the sphere had a positive charge. Other early contributors included Johann Wilhelm Hittorf (1869–1883), Eugen Goldstein (1885), and Julius Elster and Hans Friedrich Geitel (1882–1889). Thermionic emission

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