# Transistor

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Solid-state electrically operated switch also used as an amplifier

For other uses, see [Transistor (disambiguation)](/source/Transistor_(disambiguation)).

Transistor Component type Active Inventor John Bardeen Walter Brattain William Shockley Invention year 1947 First produced 1950s Pin names Base, collector, and emitter Electronic symbol NPN and PNP symbols

[Metal–oxide–semiconductor field-effect transistor (MOSFET)](/source/MOSFET), showing [gate](/source/Metal_gate) (G), body (B), source (S) and drain (D) terminals. The gate is separated from the body by an insulating layer (white).

A **transistor** is a [semiconductor device](/source/Semiconductor_device) used to [amplify](/source/Electronic_amplifier) or [switch](/source/Electronic_switch) [electrical signals](/source/Signal#Definitions) and [power](/source/Electric_power). It is one of the basic building blocks of modern [electronics](/source/Electronics).[1] It is composed of [semiconductor material](/source/Semiconductor_material), usually with at least three [terminals](/source/Terminal_(electronics)) for connection to an [electronic circuit](/source/Electronic_circuit). A [voltage](/source/Voltage) or [current](/source/Electric_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](/source/Integrated_circuit). Because transistors are the key active components in practically all modern [electronics](/source/Electronics), they are considered one of the 20th century's greatest inventions.[2]

[Physicist](/source/Physicist) [Julius Edgar Lilienfeld](/source/Julius_Edgar_Lilienfeld) proposed the concept of a [field-effect transistor](/source/Field-effect_transistor) (FET) in 1925,[3] but it was not possible to construct a working device at that time.[4] The first working device was a [point-contact transistor](/source/Point-contact_transistor) invented in 1947 by physicists [John Bardeen](/source/John_Bardeen), [Walter Brattain](/source/Walter_Brattain), and [William Shockley](/source/William_Shockley) at [Bell Labs](/source/Bell_Labs) who shared the 1956 [Nobel Prize in Physics](/source/Nobel_Prize_in_Physics) for their achievement.[5] The most widely used type of transistor, the [metal–oxide–semiconductor field-effect transistor (MOSFET)](/source/MOSFET), was invented at Bell Labs between 1955 and 1960.[6][7][8][9][10][11] Transistors revolutionized the field of electronics and paved the way for smaller and cheaper [radios](/source/Radio_receiver), [calculators](/source/Calculator), [computers](/source/Computer), and other electronic devices.

Most transistors are made from very pure [silicon](/source/Silicon), and some from [germanium](/source/Germanium), but certain other semiconductor materials are sometimes used. A transistor may have only one kind of [charge carrier](/source/Charge_carrier) in a [field-effect transistor](/source/Field-effect_transistor), or may have two kinds of charge carriers in [bipolar junction transistor](/source/Bipolar_junction_transistor) devices. Compared with the [vacuum tube](/source/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](/source/Traveling-wave_tube) and [gyrotrons](/source/Gyrotron). Many types of transistors are made to standardized specifications by multiple manufacturers.

## History

Main article: [History of the transistor](/source/History_of_the_transistor)

[Julius Edgar Lilienfeld](/source/Julius_Edgar_Lilienfeld) proposed the concept of a [field-effect transistor](/source/Field-effect_transistor) in 1925.

The [thermionic](/source/Thermionic) [triode](/source/Triode), a [vacuum tube](/source/Vacuum_tube) invented in 1907, enabled amplified [radio](/source/Radio) technology and long-distance [telephony](/source/Telephony). The triode, however, was a fragile device that consumed a substantial amount of power. In 1909, [physicist](/source/Physicist) [William Eccles](/source/William_Eccles_(physicist)) discovered the [crystal diode oscillator](/source/Crystal_oscillator).[12] Physicist [Julius Edgar Lilienfeld](/source/Julius_Edgar_Lilienfeld) filed a patent for a [field-effect transistor](/source/Field-effect_transistor) (FET) in Canada in 1925,[13] intended as a [solid-state](/source/Solid-state_electronics) replacement for the triode.[14][15] He filed identical patents in the United States in 1926[16] and 1928.[17][18] 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](/source/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 a device had been built.[19] In 1934, inventor [Oskar Heil](/source/Oskar_Heil) patented a similar device in Europe.[20]

### Bipolar transistors

Further information: [Point-contact transistor](/source/Point-contact_transistor) and [Bipolar junction transistor](/source/Bipolar_junction_transistor)

[John Bardeen](/source/John_Bardeen), [William Shockley](/source/William_Shockley), and [Walter Brattain](/source/Walter_Brattain) at [Bell Labs](/source/Bell_Labs) in 1948; Bardeen and Brattain invented the [point-contact transistor](/source/Point-contact_transistor) in 1947 and Shockley invented the [bipolar junction transistor](/source/Bipolar_junction_transistor) in 1948.

A replica of the first working transistor, a [point-contact transistor](/source/Point-contact_transistor) invented in 1947

[Herbert Mataré](/source/Herbert_Matar%C3%A9) and [Heinrich Welker](/source/Heinrich_Welker) independently invented a point-contact transistor in June 1948.

A Philco surface-barrier transistor developed and produced in 1953

From November 17 to December 23, 1947, [John Bardeen](/source/John_Bardeen) and [Walter Brattain](/source/Walter_Brattain) at [AT&T](/source/AT%26T_Corporation)'s [Bell Labs](/source/Bell_Labs) in [Murray Hill, New Jersey](/source/Murray_Hill%2C_New_Jersey), performed experiments and observed that when two gold point contacts were applied to a crystal of [germanium](/source/Germanium), a signal was produced with the output power greater than the input.[21] Solid State Physics Group leader [William Shockley](/source/William_Shockley) saw the potential in this, and over the next few months worked to greatly expand the knowledge of [semiconductors](/source/Semiconductor). The term *transistor* was coined by [John R. Pierce](/source/John_R._Pierce) as a contraction of the term *[transresistance](/source/Transresistance)*.[22][23][24] According to [Lillian Hoddeson](/source/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 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](/source/Point-contact_transistor).[19] To acknowledge this accomplishment, Shockley, Bardeen and Brattain jointly received the 1956 [Nobel Prize in Physics](/source/Nobel_Prize_in_Physics) "for their researches on semiconductors and their discovery of the transistor effect".[25][26]

Shockley's team initially attempted to build 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](/source/Surface_states), the [dangling bond](/source/Dangling_bond), and the [germanium](/source/Germanium) and [copper](/source/Copper) compound materials. Trying to understand the mysterious reasons behind this failure led them instead to invent the bipolar [point-contact](/source/Point-contact_transistor) and [junction transistors](/source/Junction_transistor).[27][28]

In 1948, the point-contact transistor was independently invented by physicists [Herbert Mataré](/source/Herbert_Matar%C3%A9) and [Heinrich Welker](/source/Heinrich_Welker) while working at the *[Compagnie des Freins et Signaux Westinghouse](https://en.wikipedia.org/w/index.php?title=Compagnie_des_Freins_et_Signaux_Westinghouse&action=edit&redlink=1)*, a [Westinghouse](/source/Westinghouse_Electric_(1886)) subsidiary in Paris. Mataré had previous experience in developing [crystal rectifiers](/source/Crystal_detector) from [silicon](/source/Silicon) and germanium in the German [radar](/source/Radar) effort during [World War II](/source/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 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.[29][30][31]

The first [bipolar junction transistors](/source/Bipolar_junction_transistor) 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](/source/Gordon_Teal) and [Morgan Sparks](/source/Morgan_Sparks) successfully produced 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.[32][33]

The first high-frequency transistor was the [surface-barrier germanium transistor](/source/Surface-barrier_transistor) developed by [Philco](/source/Philco) in 1953, capable of operating at frequencies up to 60 MHz.[34] They were made by etching depressions into an n-type germanium base from both sides with jets of [indium(III) sulfate](/source/Indium(III)_sulfate) until it was a few ten-thousandths of an inch thick. [Indium](/source/Indium) electroplated into the depressions formed the collector and emitter.[35][36]

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.[37] Its predecessor, the Western Electric No. 3A [phototransistor](/source/Phototransistor), read the mechanical encoding from punched metal cards.

The first prototype pocket [transistor radio](/source/Transistor_radio) was shown by INTERMETALL, a company founded by [Herbert Mataré](/source/Herbert_Matar%C3%A9) in 1952, at the [*Internationale Funkausstellung Düsseldorf*](/source/Internationale_Funkausstellung_Berlin) from August 29 to September 6, 1953.[38][39] The first production-model pocket transistor radio was the [Regency TR-1](/source/Regency_TR-1), released in October 1954.[26] Produced as a joint venture between the Regency Division of Industrial Development Engineering Associates, I.D.E.A. and [Texas Instruments](/source/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.[40][41][42]

The first production all-transistor car radio was developed by Chrysler and [Philco](/source/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.[43][44]

The [Sony](/source/Sony) TR-63, released in 1957, was the first mass-produced transistor radio, leading to the widespread adoption of transistor radios.[45] Seven million TR-63s were sold worldwide by the mid-1960s.[46] Sony's success with transistor radios led to transistors replacing vacuum tubes as the dominant [electronic technology](/source/Electronic_technology) in the late 1950s.[47]

The first working silicon transistor was developed at Bell Labs on January 26, 1954, by [Morris Tanenbaum](/source/Morris_Tanenbaum). The first production commercial silicon transistor was announced by [Texas Instruments](/source/Texas_Instruments) in May 1954. This was the work of [Gordon Teal](/source/Gordon_Teal), an expert in growing crystals of high purity, who had previously worked at Bell Labs.[48][49][50]

### Field-effect transistors

Main article: [Field-effect transistor](/source/Field-effect_transistor)

The basic principle of the [field-effect transistor](/source/Field-effect_transistor) (FET) was first proposed by physicist [Julius Edgar Lilienfeld](/source/Julius_Edgar_Lilienfeld) when he filed a [patent](/source/Patent) for a device similar to [MESFET](/source/MESFET) in 1926, and for an insulated-gate field-effect transistor in 1928.[15][51] The FET concept was later also theorized by engineer [Oskar Heil](/source/Oskar_Heil) in the 1930s and by [William Shockley](/source/William_Shockley) in the 1940s.

In 1945, [JFET](/source/JFET) was patented by [Heinrich Welker](/source/Heinrich_Welker).[52] Following Shockley's theoretical treatment on JFET in 1952, a working practical JFET was made in 1953 by [George C. Dacey](/source/George_C._Dacey) and [Ian M. Ross](/source/Ian_Munro_Ross).[53]

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 the concept of an inversion layer, forms the basis of CMOS and DRAM technology today.[54]

In the early years of the [semiconductor industry](/source/Semiconductor_industry), companies focused on the [junction transistor](/source/Junction_transistor), a relatively bulky device that was difficult to [mass-produce](/source/Mass-production), limiting it to several specialized applications. [Field-effect transistors](/source/Field-effect_transistor) (FETs) were theorized as potential alternatives, but researchers could not get them to work properly, largely due to the [surface state](/source/Surface_state) barrier that prevented the external [electric field](/source/Electric_field) from penetrating the material.[55]

### MOSFET (MOS transistor)

Main article: [MOSFET](/source/MOSFET)

Diagram of one of the SiO2 transistor devices made by Frosch and Derrick[7]

In 1955, [Carl Frosch](/source/Carl_Frosch) and Lincoln Derick accidentally grew a layer of silicon dioxide over the silicon wafer, for which they observed surface passivation effects.[6][56] By 1957 Frosch and Derick, using masking and predeposition, were able to manufacture silicon dioxide field-effect transistors; the first planar transistors, in which drain and source were adjacent at the same surface.[7] They showed that silicon dioxide insulated and protected silicon wafers and prevented dopants from diffusing into the wafer.[6][7] After this, J. R. Ligenza and W. G. Spitzer studied the mechanism of thermally grown oxides, fabricated a high-quality Si/[SiO2](/source/Silicon_dioxide) stack and published their results in 1960.[57][58][59]

Following this research, [Mohamed Atalla](/source/Mohamed_Atalla) and [Dawon Kahng](/source/Dawon_Kahng) proposed a silicon MOS transistor in 1959[60] and successfully demonstrated a working MOS device with their Bell Labs team in 1960.[61][62] 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.[8][9] With its [high scalability](/source/MOSFET_scaling),[63] much lower power consumption, and higher density than bipolar junction transistors,[64] the MOSFET made it possible to build [high-density integrated circuits](/source/Large-scale_integration),[65] allowing the integration of more than 10,000 transistors in a single IC.[66]

Bardeen and Brattain's 1948 inversion-layer concept forms the basis of CMOS technology today.[67] The [CMOS](/source/CMOS) (complementary [MOS](/source/MOSFET)) was invented by [Chih-Tang Sah](/source/Chih-Tang_Sah) and [Frank Wanlass](/source/Frank_Wanlass) at [Fairchild Semiconductor](/source/Fairchild_Semiconductor) in 1963.[68] The first report of a [floating-gate MOSFET](/source/Floating-gate_MOSFET) was made by Dawon Kahng and [Simon Sze](/source/Simon_Sze) in 1967.[69]

In 1967, Bell Labs researchers Robert Kerwin, [Donald Klein](/source/Donald_L._Klein) and John Sarace developed the [self-aligned gate](/source/Self-aligned_gate) (silicon-gate) MOS transistor, which Fairchild Semiconductor researchers [Federico Faggin](/source/Federico_Faggin) and Tom Klein used to develop the first [silicon-gate](/source/Silicon-gate) MOS [integrated circuit](/source/Integrated_circuit).[70]

A [double-gate](/source/Double-gate) MOSFET was first demonstrated in 1984 by [Electrotechnical Laboratory](/source/Electrotechnical_Laboratory) researchers Toshihiro Sekigawa and Yutaka Hayashi.[71][72] The [FinFET](/source/FinFET) (fin field-effect transistor), a type of 3D non-planar [multi-gate](/source/Multigate_device) MOSFET, originated from the research of Digh Hisamoto and his team at [Hitachi](/source/Hitachi) Central Research Laboratory in 1989.[73][74]

## Importance

Because transistors are the key active components in practically all modern [electronics](/source/Electronics), many people consider them one of the 20th century's greatest inventions.[2]

The 1947 invention of the first transistor at Bell Labs was named an [IEEE Milestone](/source/List_of_IEEE_milestones) in 2009.[75] Other Milestones include the inventions of the [junction transistor](/source/Junction_transistor) in 1948 and the MOSFET in 1959.[76]

The MOSFET is by far the most widely used transistor, in applications ranging from [computers](/source/Computer) and [electronics](/source/Electronics)[77] to [communications technology](/source/Communications_technology) such as [smartphones](/source/Smartphone).[78] It has been considered the most important transistor,[79] possibly the most important invention in electronics,[80] and the device that enabled modern electronics.[81] It has been the basis of modern [digital electronics](/source/Digital_electronics) since the late 20th century, paving the way for the [digital age](/source/Digital_age).[82] The [US Patent and Trademark Office](/source/US_Patent_and_Trademark_Office) calls it a "groundbreaking invention that transformed life and culture around the world".[78] Its ability to be [mass-produced](/source/Mass_production) by a highly automated process ([semiconductor device fabrication](/source/Semiconductor_device_fabrication)), from relatively basic materials, allows astonishingly low per-transistor costs. MOSFETs are the most numerously produced artificial objects in history, with more than 13 [sextillion](/source/10%5E21) manufactured by 2018.[83]

Although several companies each produce over a billion individually packaged (known as *[discrete](/source/Discrete_transistor)*) MOS transistors every year,[84] the vast majority are produced in [integrated circuits](/source/Integrated_circuits) (also known as *ICs*, *microchips,* or simply *chips*), along with [diodes](/source/Diode), [resistors](/source/Resistor), [capacitors](/source/Capacitor) and other [electronic components](/source/Electronic_component), to produce complete electronic circuits. A [logic gate](/source/Logic_gate) consists of up to about 20 transistors, whereas an advanced [microprocessor](/source/Microprocessor), As of 2023[\[update\]](https://en.wikipedia.org/w/index.php?title=Transistor&action=edit), may contain as many as [92 billion transistors on a die](/source/Apple_M3#M3_Max), and double that 184 billion when dual die (and for exceptional chips, 2.6 trillion transistors, as of 2020).[85] Transistors are often organized into logic gates in microprocessors to perform computation.[86]

The transistor's low cost, flexibility and reliability have made it ubiquitous. Transistorized [mechatronic](/source/Mechatronics) circuits have replaced [electromechanical devices](/source/Cam_timer) in controlling appliances and machinery. It is often easier and cheaper to use a standard [microcontroller](/source/Microcontroller) and write a [computer program](/source/Computer_program) to carry out a control function than to design an equivalent mechanical system.

## Simplified operation

A simple circuit diagram showing the labels of an n–p–n bipolar transistor

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](/source/Gain_(electronics)). It can produce a stronger output signal, a voltage or current, proportional to a weaker input signal, acting as an [amplifier](/source/Amplifier). It can also be used as an electrically controlled [switch](/source/Switch), where the amount of current is determined by other circuit elements.[87]

There are two types of transistors, with slight differences in how they are used:

- A *[bipolar junction transistor (BJT)](/source/Bipolar_transistor)* has terminals labeled **base**, **collector** and **emitter**. A small current at the base terminal, flowing between the base and the emitter, can control or switch a much larger current between the collector and emitter.

- A *[field-effect transistor (FET)](/source/Field-effect_transistor)* has terminals labeled **gate**, **source** and **drain**. A voltage at the gate can control a current between source and drain.[88]

The top image in this section represents a typical bipolar transistor in a circuit. A charge flows between emitter and collector terminals depending on 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.[88] (Base Emitter Voltage)

### Transistor as a switch

BJT used as an electronic switch in grounded-emitter configuration

Transistors are commonly used in [digital circuits](/source/Digital_circuit) as [electronic switches](/source/Electronic_switches) which can be either in an *on* or *off* state, both for high-power applications such as [switched-mode power supplies](/source/Switched-mode_power_supply) and for low-power applications such as [logic gates](/source/Logic_gate). Important parameters for this application include the current switched, the voltage handled, and the switching speed, characterized by the [rise and fall times](/source/Rise_time).[88]

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, 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.[88]

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 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*.[89]

The use of bipolar transistors for switching applications requires biasing 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 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.[88] The base resistor value is calculated from the supply voltage, transistor C-E junction voltage drop, collector current, and amplification factor beta.[90]

### Transistor as an amplifier

An amplifier circuit, a common-emitter configuration with a voltage-divider bias circuit

The [common-emitter amplifier](/source/Common-emitter_amplifier) is designed so that 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.[88]

Various configurations of single transistor amplifiers are possible, with some providing current gain, some voltage gain, and some both.

From [mobile phones](/source/Mobile_phone) to [televisions](/source/Television), vast numbers of products include amplifiers for [sound reproduction](/source/Sound_reproduction), [radio transmission](/source/Transmitter), and [signal processing](/source/Signal_processing). The first discrete-transistor audio amplifiers barely supplied a few hundred milliwatts, but power and audio fidelity gradually increased as better transistors became available and amplifier architecture evolved.[88]

Modern transistor audio amplifiers of up to a few hundred [watts](/source/Watt) are common and relatively inexpensive.

## Comparison with vacuum tubes

Before transistors were developed, [vacuum (electron) tubes](/source/Vacuum_tube) (or in the UK *thermionic valves* or just *valves*) were the main active components in electronic equipment.

### Advantages

The key advantages that have allowed transistors to replace vacuum tubes in most applications are

- No cathode heater (which produces the characteristic orange glow of tubes), reducing power consumption, eliminating delay as tube heaters warm up, and immune from [cathode poisoning](/source/Cathode_poisoning) and depletion.

- Very small size and weight, reducing equipment size.

- Large numbers of extremely small transistors can be manufactured as a single [integrated circuit](/source/Integrated_circuit).

- Low operating voltages compatible with batteries of only a few cells.

- Circuits with greater energy efficiency are usually possible. For low-power applications (for example, voltage amplification) in particular, energy consumption can be very much less than for tubes.

- Complementary devices available, providing design flexibility including complementary-symmetry circuits, not possible with vacuum tubes.

- Very low sensitivity to mechanical shock and vibration, providing physical ruggedness and virtually eliminating shock-induced spurious signals (for example, [microphonics](/source/Microphonics) in audio applications).

- Not susceptible to breakage of a glass envelope, leakage, outgassing, and other physical damage.

### Limitations

Transistors may have the following limitations:

- They lack the higher [electron mobility](/source/Electron_mobility) afforded by the vacuum of vacuum tubes, which is desirable for high-power, high-frequency operation – such as that used in some over-the-air [television transmitters](/source/Television_transmitter) and in [travelling-wave tubes](/source/Travelling-wave_tube) used as amplifiers in some satellites

- Transistors and other solid-state devices are susceptible to damage from very brief electrical and thermal events, including [electrostatic discharge](/source/Electrostatic_discharge) in handling. Vacuum tubes are electrically much more rugged.

- They are sensitive to radiation and [cosmic rays](/source/Cosmic_ray) (special [radiation-hardened](/source/Radiation_hardening) chips are used for spacecraft devices).

- In audio applications, transistors lack the lower-harmonic distortion – the so-called [tube sound](/source/Tube_sound) – which is characteristic of vacuum tubes, and is preferred by some.[91]

## Types

### Classification

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PNP P-channel NPN N-channel BJT JFET

BJT and JFET symbols

Insulated-gate bipolar transistor (IGBT)

P-channel N-channel MOSFET enh MOSFET dep

MOSFET symbols

Transistors are categorized by

- Structure: [MOSFET](/source/MOSFET) (IGFET), [BJT](/source/Bipolar_junction_transistor), [JFET](/source/JFET), [insulated-gate bipolar transistor](/source/Insulated-gate_bipolar_transistor) (IGBT), other type.[*[which?](https://en.wikipedia.org/wiki/Wikipedia:Avoid_weasel_words)*].

- Semiconductor material ([dopants](/source/Dopant)): - The [metalloids](/source/Metalloids); [germanium](/source/Germanium) (first used in 1947) and [silicon](/source/Silicon) (first used in 1954)—in [amorphous](/source/Amorphous_silicon), [polycrystalline](/source/Polycrystalline_silicon) and [monocrystalline](/source/Monocrystalline_silicon) form. - The compounds [gallium arsenide](/source/Gallium_arsenide) (1966) and [silicon carbide](/source/Silicon_carbide) (1997). - The [alloy](/source/Alloy) [silicon–germanium](/source/Silicon%E2%80%93germanium) (1989) - The [allotrope of carbon](/source/Allotrope_of_carbon) [graphene](/source/Graphene#Electronics) (research ongoing since 2004), etc. (see [Semiconductor material](#Semiconductor_material)).

- [Electrical polarity](/source/Electrical_polarity) (positive and negative): [NPN](/source/NPN_transistor), [PNP](/source/PNP_transistor) (BJTs), N-channel, P-channel (FETs).

- Maximum [power rating](/source/Power_rating): low, medium, high.

- Maximum operating frequency: low, medium, high, [radio](/source/Radio_frequency) (RF), [microwave](/source/Microwave) frequency (the maximum effective frequency of a transistor in a common-emitter or common-source circuit is denoted by the term *f**T*, an abbreviation for [transition frequency](/source/Gain%E2%80%93bandwidth_product#Transistors)—the frequency at which the transistor yields unity voltage gain)

- Application: switch, general purpose, audio, [high voltage](/source/High_voltage), super-beta, matched pair.

- Physical packaging: [through-hole](/source/Through-hole_technology) metal, through-hole plastic, [surface mount](/source/Surface-mount_technology), [ball grid array](/source/Ball_grid_array), power modules (see [Packaging](#Packaging)).

- Amplification factor [*h**FE*](/source/Transistor_models), *β**F* ([transistor beta](/source/Transistor_beta))[92] or *g**m* ([transconductance](/source/Transconductance)).

- Working temperature: Extreme temperature transistors and traditional temperature transistors (−55 to 150 °C (−67 to 302 °F)). Extreme temperature transistors include high-temperature transistors (above 150 °C (302 °F)) and low-temperature transistors (below −55 °C (−67 °F)). The high-temperature transistors that operate thermally stable up to 250 °C (482 °F) can be developed by a general strategy of blending interpenetrating semi-crystalline conjugated polymers and high glass-transition temperature insulating polymers.[93]

Hence, a particular transistor may be described as *silicon, surface-mount, BJT, NPN, low-power, high-frequency switch*.

### Mnemonics

Convenient [mnemonic](/source/Mnemonic) to remember the type of transistor (represented by an [electrical symbol](/source/Electrical_symbol)) involves the direction of the arrow. For the [BJT](/source/Bipolar_junction_transistor), on an **n–p–n** transistor symbol, the arrow will "**N**ot **P**oint i**N"**. On 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).

### Field-effect transistor (FET)

Main article: [Field-effect transistor](/source/Field-effect_transistor)

See also: [JFET](/source/JFET)

Operation of an [FET](/source/FET) and its Id-Vg curve. At first, when no gate voltage is applied, there are no inversion electrons in the channel, so the device is turned off. As gate voltage increases, the inversion electron density in the channel increases, the current increases, and the device turns on.

The *[field-effect transistor](/source/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, 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 the drain and source is controlled by the voltage applied between the gate and source. As the gate–source voltage (VGS) is increased, the drain–source current (IDS) increases exponentially for VGS below threshold, and then at a roughly quadratic rate: (*IDS* ∝ (*VGS* − *VT*)2, where VT is the threshold voltage at which drain current begins)[94] in the [space-charge-limited](/source/Space_charge) region above threshold. A quadratic behavior is not observed in modern devices, for example, at the [65 nm](/source/65_nanometer) technology node.[95]

For low noise at narrow [bandwidth](/source/Bandwidth_(signal_processing)), the higher input resistance of the FET is advantageous.

FETs are divided into two families: *junction FET* ([JFET](/source/JFET)) and *insulated gate FET* (IGFET). The IGFET is more commonly known as a *metal–oxide–semiconductor FET* ([MOSFET](/source/MOSFET)), reflecting its original construction from layers of metal (the gate), oxide (the insulation), and semiconductor. Unlike IGFETs, the JFET gate forms a [p–n diode](/source/P%E2%80%93n_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](/source/Triode) which, similarly, forms a diode between its [grid](/source/Control_grid) and [cathode](/source/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.

Metal–semiconductor FETs ([MESFETs](/source/MESFET)) are JFETs in which the [reverse biased](/source/Reverse-biased) p–n junction is replaced by a [metal–semiconductor junction](/source/Metal%E2%80%93semiconductor_junction). These, and the HEMTs (high-electron-mobility transistors, or HFETs), in which a two-dimensional electron gas with very high carrier mobility is used for charge transport, are especially suitable for use at very high frequencies (several GHz).

FETs are further divided into *depletion-mode* and *enhancement-mode* types, depending on whether the channel is turned on or off with zero gate-to-source voltage. For enhancement mode, the channel is off at zero bias, and a gate potential can *enhance* the conduction. For the depletion mode, the channel is on at zero bias, and a gate potential (of the opposite polarity) can *deplete* the channel, reducing conduction. For either mode, a more positive gate voltage corresponds to a higher current for n-channel devices and a lower current for p-channel devices. Nearly all JFETs are depletion-mode because the diode junctions would forward bias and conduct if they were enhancement-mode devices, while most IGFETs are enhancement-mode types.

#### Metal–oxide–semiconductor FET (MOSFET)

Main article: [MOSFET](/source/MOSFET)

The metal–oxide–semiconductor field-effect transistor ([MOSFET](/source/MOSFET), MOS-FET, or MOS FET), also known as the metal–oxide–silicon transistor (MOS transistor, or MOS),[65] is a type of field-effect transistor that is [fabricated](/source/Semiconductor_device_fabrication) by the [controlled oxidation](/source/Thermal_oxidation) of a semiconductor, typically [silicon](/source/Silicon). It has an insulated [gate](/source/Metal_gate), whose voltage 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](/source/Signal_(electrical_engineering)). The MOSFET is by far the most common transistor, and the basic building block of most modern [electronics](/source/Electronics).[82] The MOSFET accounts for 99.9% of all transistors in the world.[96]

### Bipolar junction transistor (BJT)

Main article: [Bipolar junction transistor](/source/Bipolar_junction_transistor)

2N2222A NPN transistor

Bipolar transistors are so named because they conduct by using both majority and minority [carriers](/source/Charge_carrier). The bipolar junction transistor, the first type of transistor to be mass-produced, is a combination of two junction diodes and is formed of either a thin layer of p-type semiconductor sandwiched between two n-type semiconductors (an n–p–n transistor), or a thin layer of n-type semiconductor sandwiched between two p-type semiconductors (a p–n–p transistor). This construction produces two [p–n junctions](/source/P%E2%80%93n_junction): a base–emitter junction and a base–collector junction, separated by a thin region of semiconductor known as the base region. (Two junction diodes wired together without sharing an intervening semiconducting region will not make a transistor.)

BJTs have three terminals, corresponding to the three layers of semiconductor—an *emitter*, a *base*, and a *collector*. They are useful in [amplifiers](/source/Amplifier) because the currents at the emitter and collector are controllable by a relatively small base current.[97] In an n–p–n transistor operating in the active region, the emitter–base junction is forward-biased ([electrons](/source/Electron) and [holes](/source/Electron_hole) recombine at the junction), and the base–collector junction is reverse-biased (electrons and holes are formed at, and move away from, the junction), and electrons are injected into the base region. Because the base is narrow, most of these electrons will diffuse into the reverse-biased base–collector junction and be swept into the collector; perhaps one-hundredth of the electrons will recombine in the base, which is the dominant mechanism in the base current. Since the base is doped lightly (in comparison to the emitter and collector regions), recombination rates are low, permitting more carriers to diffuse across the base region. By controlling the number of electrons that can leave the base, the number of electrons entering the collector can be controlled.[97] Collector current is approximately β (common-emitter current gain) times the base current. It is typically greater than 100 for small-signal transistors but can be smaller in transistors designed for high-power applications.

Unlike the field-effect transistor (see below), the BJT is a low-input-impedance device. Also, as the base–emitter voltage (*V*BE) is increased, the base–emitter current and hence the collector–emitter current (*I*CE) increase exponentially according to the [Shockley diode model](/source/Diode_modelling#Shockley_diode_model) and the [Ebers–Moll model](/source/Ebers%E2%80%93Moll_model). Because of this exponential relationship, the BJT has a higher [transconductance](/source/Transconductance) than the FET.

Bipolar transistors can be made to conduct by exposure to light because the absorption of photons in the base region generates a photocurrent that acts as a base current; the collector current is approximately β times the photocurrent. Devices designed for this purpose have a transparent window in the package and are called [phototransistors](/source/Phototransistor).

### Usage of MOSFETs and BJTs

The [MOSFET](/source/MOSFET) is by far the most widely used transistor for both [digital circuits](/source/Digital_circuit) as well as [analog circuits](/source/Analog_circuit),[98] accounting for 99.9% of all transistors in the world.[96] The [bipolar junction transistor](/source/Bipolar_junction_transistor) (BJT) was previously the most commonly used transistor during the 1950s to 1960s. Even after MOSFETs became widely available in the 1970s, the BJT remained the transistor of choice for many analog circuits such as amplifiers because of their greater linearity, up until MOSFET devices (such as [power MOSFETs](/source/Power_MOSFET), [LDMOS](/source/LDMOS) and [RF CMOS](/source/RF_CMOS)) replaced them for most [power electronic](/source/Power_electronic) applications in the 1980s. In [integrated circuits](/source/Integrated_circuit), the desirable properties of MOSFETs allowed them to capture nearly all market share for digital circuits in the 1970s. Discrete MOSFETs (typically power MOSFETs) can be applied in transistor applications, including analog circuits, voltage regulators, amplifiers, power transmitters, and motor drivers.

### Other transistor types

A transistor symbol created on [Portuguese pavement](/source/Portuguese_pavement) at the [University of Aveiro](/source/University_of_Aveiro)

For early bipolar transistors, see [Bipolar junction transistor § Bipolar transistors](/source/Bipolar_junction_transistor#Bipolar_transistors).

- [Field-effect transistor](/source/Field-effect_transistor) (FET): - [Metal–oxide–semiconductor field-effect transistor (MOSFET)](/source/MOSFET), where the gate is insulated by a shallow layer of insulator - [p-type MOS](/source/PMOS_logic) (PMOS) - [n-type MOS](/source/NMOS_logic) (NMOS) - [Complementary MOS](/source/CMOS) (CMOS) - [RF CMOS](/source/RF_CMOS), for [radiofrequency](/source/Radiofrequency) amplification, reception - [Multi-gate field-effect transistor](/source/Multi-gate_field-effect_transistor) (MuGFET) - [Fin field-effect transistor](/source/Fin_field-effect_transistor) (FinFET), source/drain region shapes fins on the silicon surface - GAAFET, similar to FinFET but nanowires are used instead of fins, the nanowires are stacked vertically and are surrounded on 4 sides by the gate - MBCFET, a variant of GAAFET that uses horizontal nanosheets instead of nanowires, made by Samsung. Also known as RibbonFET (made by Intel) and as horizontal nanosheet transistor. - [Thin-film transistor](/source/Thin-film_transistor) (TFT), used in [LCD](/source/Liquid-crystal_display) and [OLED](/source/OLED) displays, types include amorphous silicon, LTPS, LTPO and IGZO transistors - [Floating-gate MOSFET](/source/Floating-gate_MOSFET) (FGMOS), for [non-volatile storage](/source/Non-volatile_storage) - [Power MOSFET](/source/Power_MOSFET), for power electronics - [lateral diffused MOS](/source/LDMOS) (LDMOS) - [Carbon nanotube field-effect transistor](/source/Carbon_nanotube_field-effect_transistor) (CNFET, CNTFET), where the channel material is replaced by a carbon nanotube. - Ferroelectric field-effect transistor ([Fe FET](/source/Fe_FET)), uses ferroelectric materials - [Junction gate field-effect transistor](/source/Junction_gate_field-effect_transistor) (JFET), where the gate is insulated by a reverse-biased p–n junction. - [Metal–semiconductor field-effect transistor](/source/Metal%E2%80%93semiconductor_field-effect_transistor) (MESFET), similar to JFET with a Schottky junction instead of a p–n junction - [High-electron-mobility transistor](/source/High-electron-mobility_transistor) (HEMT): GaN (gallium nitride), SiC (silicon carbide), Ga2O3 (gallium oxide), GaAs (gallium arsenide) transistors, MOSFETs, etc. - Negative-capacitance FET (NC-FET) - [Inverted-T field-effect transistor](/source/Inverted-T_field-effect_transistor) (ITFET) - [Fast-reverse epitaxial diode field-effect transistor](/source/Fast-reverse_epitaxial_diode_field-effect_transistor) (FREDFET) - [Organic field-effect transistor](/source/Organic_field-effect_transistor) (OFET), in which the semiconductor is an organic compound. - [Ballistic transistor (disambiguation)](/source/Ballistic_transistor_(disambiguation)) - FETs used to sense the environment - [Ion-sensitive field-effect transistor](/source/Ion-sensitive_field-effect_transistor) (ISFET), to measure ion concentrations in solution - [Electrolyte–oxide–semiconductor field-effect transistor](/source/Electrolyte%E2%80%93oxide%E2%80%93semiconductor_field-effect_transistor) (EOSFET), [neurochip](/source/Neurochip), - [Deoxyribonucleic acid field-effect transistor](/source/Deoxyribonucleic_acid_field-effect_transistor) (DNAFET). - Field-effect transistor-based biosensor ([Bio-FET](/source/Bio-FET))

- [Bipolar junction transistor](/source/Bipolar_junction_transistor) (BJT): - [Heterojunction bipolar transistor](/source/Heterojunction_bipolar_transistor), up to several hundred GHz, common in modern ultrafast and RF circuits - [Schottky transistor](/source/Schottky_transistor) - [avalanche transistor](/source/Avalanche_transistor) - A [Darlington transistor](/source/Darlington_transistor) with the upper case removed so the transistor chip (the small square) can be seen. It is effectively two transistors on the same chip. One is much larger than the other, but both are large in comparison to transistors in [large-scale integration](/source/Large-scale_integration) because this particular example is intended for power applications. [Darlington transistors](/source/Darlington_transistor) are two BJTs connected together to provide a high current gain equal to the product of the current gains of the two transistors - [Insulated-gate bipolar transistors](/source/Insulated-gate_bipolar_transistor) (IGBTs) use a medium-power IGFET, similarly connected to a power BJT, to give a high input impedance. Power diodes are often connected between certain terminals depending on specific use. IGBTs are particularly suitable for heavy-duty industrial applications. The [ASEA Brown Boveri](/source/ASEA_Brown_Boveri) (ABB) *5SNA2400E170100* ,[99] intended for three-phase power supplies, houses three n–p–n IGBTs in a case measuring 38 by 140 by 190 mm and weighing 1.5 kg. Each IGBT is rated at 1,700 volts and can handle 2,400 amperes - [Phototransistor](/source/Phototransistor) - [Emitter-switched bipolar transistor](https://en.wikipedia.org/w/index.php?title=Emitter-switched_bipolar_transistor&action=edit&redlink=1) (ESBT) is a monolithic configuration of a high-voltage bipolar transistor and a low-voltage power MOSFET in [cascode](/source/Cascode) topology. It was introduced by STMicroelectronics in the 2000s,[100] and abandoned a few years later around 2012.[101] - [Multiple-emitter transistor](/source/Multiple-emitter_transistor), used in [transistor–transistor logic](/source/Transistor%E2%80%93transistor_logic) and integrated current mirrors - [Multiple-base transistor](https://en.wikipedia.org/w/index.php?title=Multiple-base_transistor&action=edit&redlink=1), used to amplify very-low-level signals in noisy environments such as the pickup of a [record player](/source/Record_player) or [radio front ends](/source/RF_front_end). Effectively, it is a very large number of transistors in parallel where, at the output, the signal is added constructively, but random noise is added only [stochastically](/source/Stochastic).[102]

- [Tunnel field-effect transistor](/source/Tunnel_field-effect_transistor), where it switches by modulating [quantum tunneling](/source/Quantum_tunneling) through a barrier.

- [Diffusion transistor](/source/Diffusion_transistor), formed by diffusing dopants into semiconductor substrate; can be both BJT and FET.

- [Unijunction transistor](/source/Unijunction_transistor), which can be used as a simple pulse generator. It comprises the main body of either p-type or n-type semiconductor with ohmic contacts at each end (terminals *Base1* and *Base2*). A junction with the opposite semiconductor type is formed at a point along the length of the body for the third terminal (*Emitter*).

- [Single-electron transistors](/source/Single-electron_transistor) (SET), consist of a gate island between two tunneling junctions. The tunneling current is controlled by a voltage applied to the gate through a capacitor.[103]

- [Nanofluidic transistor](/source/Nanofluidic_transistor), controls the movement of ions through sub-microscopic, water-filled channels.[104]

- [Multigate devices](/source/Multigate_device): - [Tetrode transistor](/source/Tetrode_transistor) - [Pentode transistor](/source/Pentode_transistor) - [Trigate transistor](/source/Trigate_transistor) (prototype by Intel) - [Dual-gate field-effect transistors](/source/Dual-gate_field-effect_transistor) have a single channel with two gates in [cascode](/source/Cascode), a configuration optimized for *high-frequency amplifiers*, *mixers*, and [oscillators](/source/Oscillators).

- [Junctionless nanowire transistor](/source/Junctionless_nanowire_transistor) (JNT), uses a simple nanowire of silicon surrounded by an electrically isolated *wedding ring* that acts to gate the flow of electrons through the wire.

- [Nanoscale vacuum-channel transistor](/source/Nanoscale_vacuum-channel_transistor), when in 2012, NASA and the National Nanofab Center in South Korea were reported to have built a prototype vacuum-channel transistor in only 150 nanometers in size, can be manufactured cheaply using standard silicon semiconductor processing, can operate at high speeds even in hostile environments, and could consume just as much power as a standard transistor.[105]

- [Organic electrochemical transistor](/source/Organic_electrochemical_transistor).

- [Solaristor](/source/Solaristor) (from solar cell transistor), a two-terminal gate-less self-powered phototransistor.

- Germanium–tin transistor[106]

- Wood transistor[107][108]

- Paper transistor[109]

- [Carbon-doped silicon–germanium (Si–Ge:C)](/source/Communicant_Semiconductor_Technologies) transistor

- Diamond transistor[110]

- Aluminum nitride transistor[111]

- Super-lattice castellated field effect transistors[112]

## Device identification

Three major identification standards are used for designating transistor devices. In each, the alphanumeric prefix provides clues to the type of the device.

### Joint Electron Device Engineering Council (JEDEC)

The [JEDEC](/source/JEDEC) part numbering scheme evolved in the 1960s in the United States. The JEDEC *EIA-370* transistor device numbers usually start with *2N*, indicating a three-terminal device.[113] Dual-gate [field-effect transistors](/source/Field-effect_transistor) are four-terminal devices, and begin with 3N. The prefix is followed by a two-, three- or four-digit number with no significance as to device properties, although early devices with low numbers tend to be germanium devices. For example, [2N3055](/source/2N3055) is a silicon n–p–n power transistor, 2N1301 is a p–n–p germanium switching transistor. A letter suffix, such as A, is sometimes used to indicate a newer variant, but rarely gain groupings.

JEDEC prefix table Prefix Type and usage 1N two-terminal device, such as diodes 2N three-terminal device, such as transistors or single-gate field-effect transistors 3N four-terminal device, such as dual-gate field-effect transistors

### Japanese Industrial Standard (JIS)

In Japan, the [JIS semiconductor designation](/source/JIS_semiconductor_designation) (|JIS-C-7012), labels transistor devices starting with *2S*,[114] e.g., 2SD965, but sometimes the 2S prefix is not marked on the package–a 2SD965 might only be marked *D965* and a 2SC1815 might be listed by a supplier as simply *C1815*. This series sometimes has suffixes, such as R, O, BL, standing for red, orange, blue, etc., to denote variants, such as tighter *h*FE (gain) groupings.

JIS transistor prefix table Prefix Type and usage 2SA high-frequency p–n–p BJT 2SB audio-frequency p–n–p BJT 2SC high-frequency n–p–n BJT 2SD audio-frequency n–p–n BJT 2SJ P-channel FET (both JFET and MOSFET) 2SK N-channel FET (both JFET and MOSFET)

### European Electronic Component Manufacturers Association (EECA)

The European Electronic Component Manufacturers Association (EECA) uses a numbering scheme that was inherited from [Pro Electron](/source/Pro_Electron) when it merged with EECA in 1983. This scheme begins with two letters: the first gives the semiconductor type (A for germanium, B for silicon, and C for materials like GaAs); the second letter denotes the intended use (A for diode, C for general-purpose transistor, etc.). A three-digit sequence number (or one letter and two digits, for industrial types) follows. With early devices this indicated the case type. Suffixes may be used, with a letter (e.g. C often means high *h*FE, such as in: BC549C[115]) or other codes may follow to show gain (e.g. BC327-25) or voltage rating (e.g. BUK854-800A[116]). The more common prefixes are:

EECA transistor prefix table Prefix Type and usage Example Equivalent Reference AC Germanium, small-signal AF transistor AC126 NTE102A AD Germanium, AF power transistor AD133 NTE179 AF Germanium, small-signal RF transistor AF117 NTE160 AL Germanium, RF power transistor ALZ10 NTE100 AS Germanium, switching transistor ASY28 NTE101 AU Germanium, power switching transistor AU103 NTE127 BC Silicon, small-signal transistor ("general purpose") BC548 2N3904 Datasheet BD Silicon, power transistor BD139 NTE375 Datasheet BF Silicon, RF (high frequency) BJT or FET BF245 NTE133 Datasheet BS Silicon, switching transistor (BJT or MOSFET) BS170 2N7000 Datasheet BL Silicon, high frequency, high power (for transmitters) BLW60 NTE325 Datasheet BU Silicon, high voltage (for CRT horizontal deflection circuits) BU2520A NTE2354 Datasheet CF Gallium arsenide, small-signal microwave transistor (MESFET) CF739 — Datasheet CL Gallium arsenide, microwave power transistor (FET) CLY10 — Datasheet

### Proprietary

Manufacturers of devices may have their proprietary numbering system, for example [CK722](/source/CK722). Since devices are [second-sourced](/source/Second_source), a manufacturer's prefix (like MPF in MPF102, which originally would denote a [Motorola](/source/Motorola) [FET](/source/FET)) now is an unreliable indicator of who made the device. Some proprietary naming schemes adopt parts of other naming schemes, for example, a PN2222A is a (possibly [Fairchild Semiconductor](/source/Fairchild_Semiconductor)) 2N2222A in a plastic case (but a PN108 is a plastic version of a BC108, not a 2N108, while the PN100 is unrelated to other xx100 devices).

Military part numbers sometimes are assigned their codes, such as the [British Military CV Naming System](https://en.wikipedia.org/w/index.php?title=UK_CV_series&action=edit&redlink=1).

Manufacturers buying large numbers of similar parts may have them supplied with *house numbers*, identifying a particular purchasing specification and not necessarily a device with a standardized registered number. For example, an HP part 1854,0053 is a (JEDEC) 2N2218 transistor[117][118] which is also assigned the CV number: CV7763[119]

### Naming problems

With so many independent naming schemes, and the abbreviation of part numbers when printed on the devices, ambiguity sometimes occurs. For example, two different devices may be marked J176 (one the J176 low-power [JFET](/source/JFET), the other the higher-powered [MOSFET](/source/MOSFET) 2SJ176).

As older through-hole transistors are given surface-mount packaged counterparts, they tend to be assigned many different part numbers because manufacturers have their systems to cope with the variety in [pinout](/source/Pinout) arrangements and options for dual or matched n–p–n + p–n–p devices in one pack. So even when the original device (such as a 2N3904) may have been assigned by a standards authority, and well known by engineers over the years, the new versions are far from standardized in their naming.

## Construction

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### Semiconductor material

Semiconductor material characteristics Semiconductor material Junction forward voltage @ 25 °C, V Electron mobility @ 25 °C, m2/(V·s) Hole mobility @ 25 °C, m2/(V·s) Max. junction temp., °C Ge 0.27 0.39 0.19 70 to 100 Si 0.71 0.14 0.05 150 to 200 GaAs 1.03 0.85 0.05 150 to 200 Al–Si junction 0.3 — — 150 to 200

The first BJTs were made from [germanium](/source/Germanium) (Ge). [Silicon](/source/Silicon) (Si) types currently predominate but certain advanced microwave and high-performance versions now employ the *compound semiconductor* material [gallium arsenide](/source/Gallium_arsenide) (GaAs) and the *semiconductor alloy* [silicon–germanium](/source/Silicon%E2%80%93germanium) (SiGe). Single-element semiconductor material (Ge and Si) is described as *elemental*.

Rough parameters for the most common semiconductor materials used to make transistors are given in the adjacent table. These parameters will vary with an increase in temperature, electric field, impurity level, strain, and sundry other factors.

The *junction forward voltage* is the voltage applied to the emitter-base junction of a BJT to make the base conduct a specified current. The current increases exponentially as the junction forward voltage is increased. The values given in the table are typical for a current of 1 mA (the same values apply to semiconductor diodes). The lower the junction forward voltage the better, as this means that less power is required to drive the transistor. The junction forward voltage for a given current decreases with an increase in temperature. For a typical silicon junction, the change is −2.1 mV/°C.[120] In some circuits special compensating elements ([sensistors](/source/Sensistor)) must be used to compensate for such changes.

The density of mobile carriers in the channel of a MOSFET is a function of the electric field forming the channel and of various other phenomena such as the impurity level in the channel. Some impurities, called dopants, are introduced deliberately in making a MOSFET, to control the MOSFET electrical behavior.

The *[electron mobility](/source/Electron_mobility)* and *[hole mobility](/source/Hole_mobility)* columns show the average speed that electrons and holes diffuse through the semiconductor material with an [electric field](/source/Electric_field) of 1 volt per meter applied across the material. In general, the higher the electron mobility the faster the transistor can operate. The table indicates that Ge is a better material than Si in this respect. However, Ge has four major shortcomings compared to silicon and gallium arsenide:

1. Its maximum temperature is limited.

1. It has relatively high [leakage current](/source/Reverse_leakage_current).

1. It cannot withstand high voltages.

1. It is less suitable for fabricating integrated circuits.

Because the electron mobility is higher than the hole mobility for all semiconductor materials, a given bipolar [n–p–n transistor](/source/N%E2%80%93p%E2%80%93n_transistor) tends to be swifter than an equivalent [p–n–p transistor](/source/P%E2%80%93n%E2%80%93p_transistor). GaAs has the highest electron mobility of the three semiconductors. It is for this reason that GaAs is used in high-frequency applications. A relatively recent[*[when?](https://en.wikipedia.org/wiki/Wikipedia:Manual_of_Style/Dates_and_numbers#Chronological_items)*] FET development, the *[high-electron-mobility transistor](/source/High-electron-mobility_transistor)* (HEMT), has a [heterostructure](/source/Heterojunction) (junction between different semiconductor materials) of aluminium gallium arsenide (AlGaAs)-gallium arsenide (GaAs) which has twice the electron mobility of a GaAs-metal barrier junction. Because of their high speed and low noise, HEMTs are used in satellite receivers working at frequencies around 12 GHz. HEMTs based on [gallium nitride](/source/Gallium_nitride) and [aluminum gallium nitride](/source/Aluminum_gallium_nitride) (AlGaN/GaN HEMTs) provide still higher electron mobility and are being developed for various applications.

Maximum [junction temperature](/source/Junction_temperature) values represent a cross-section taken from various manufacturers' datasheets. This temperature should not be exceeded or the transistor may be damaged.

*Al–Si junction* refers to the high-speed (aluminum-silicon) metal–semiconductor barrier diode, commonly known as a [Schottky diode](/source/Schottky_diode). This is included in the table because some silicon power IGFETs have a [parasitic](/source/Parasitic_structure) reverse Schottky diode formed between the source and drain as part of the fabrication process. This diode can be a nuisance, but sometimes it is used in the circuit.

### Packaging

See also: [Semiconductor package](/source/Semiconductor_package) and [Chip carrier](/source/Chip_carrier)

Assorted discrete transistors

[Soviet](/source/Soviet_Union)-manufactured [KT315b](/source/KT315) transistors

Discrete transistors can be individually packaged transistors or unpackaged transistor chips.

Transistors come in many different [semiconductor packages](/source/Semiconductor_package) (see image). The two main categories are *[through-hole](/source/Through-hole_technology)* (or *leaded*), and *surface-mount*, also known as *surface-mount device* ([SMD](/source/Surface-mount_technology)). The *ball grid array* ([BGA](/source/Ball_grid_array)) is the latest surface-mount package. It has solder balls on the underside in place of leads. Because they are smaller and have shorter interconnections, SMDs have better high-frequency characteristics but lower power ratings.

Transistor packages are made of glass, metal, ceramic, or plastic. The package often dictates the power rating and frequency characteristics. Power transistors have larger packages that can be clamped to [heat sinks](/source/Heat_sink) for enhanced cooling. Additionally, most power transistors have the collector or drain physically connected to the metal enclosure. At the other extreme, some surface-mount *microwave* transistors are as small as grains of sand.

Often a given transistor type is available in several packages. Transistor packages are mainly standardized, but the assignment of a transistor's functions to the terminals is not: other transistor types can assign other functions to the package's terminals. Even for the same transistor type the terminal assignment can vary (normally indicated by a suffix letter to the part number, q.e. BC212L and BC212K).

Nowadays most transistors come in a wide range of SMT packages. In comparison, the list of available through-hole packages is relatively small. Here is a short list of the most common through-hole transistors packages in alphabetical order: ATV, E-line, MRT, HRT, SC-43, SC-72, TO-3, TO-18, TO-39, TO-92, TO-126, TO220, TO247, TO251, TO262, ZTX851.

Unpackaged transistor chips (die) may be assembled into hybrid devices.[121] The [IBM SLT](/source/IBM_SLT) module of the 1960s is one example of such a hybrid circuit module using glass passivated transistor (and diode) die. Other packaging techniques for discrete transistors as chips include *direct chip attach* (DCA) and *chip-on-board* (COB).[121]

#### Flexible transistors

Researchers have made several kinds of flexible transistors, including [organic field-effect transistors](/source/Organic_field-effect_transistor).[122][123][124] Flexible transistors are useful in some kinds of [flexible displays](/source/Flexible_display) and other [flexible electronics](/source/Flexible_electronics).

## See also

- [Electronics portal](https://en.wikipedia.org/wiki/Portal:Electronics)

- [Alpha cutoff frequency](/source/Alpha_cutoff_frequency)

- [Band gap](/source/Band_gap)

- [Digital electronics](/source/Digital_electronics)

- [Diffused junction transistor](/source/Diffused_junction_transistor)

- [Moore's law](/source/Moore's_law)

- [Optical transistor](/source/Optical_transistor)

- [Magneto-Electric Spin-Orbit](/source/Magneto-Electric_Spin-Orbit)

- [Nanoelectromechanical relay](/source/Nanoelectromechanical_relay)

- [Semiconductor device modeling](/source/Semiconductor_device_modeling)

- [Transistor count](/source/Transistor_count)

- [Transistor model](/source/Transistor_model)

- [Transresistance](/source/Transresistance)

- [Very Large Scale Integration](/source/Very_Large_Scale_Integration)

- [Trancitor](/source/Trancitor)

## References

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1. **[^](#cite_ref-14)** Vardalas, John (May 2003) [Twists and Turns in the Development of the Transistor](http://www.todaysengineer.org/2003/May/history.asp) [Archived](https://web.archive.org/web/20150108082709/http://www.todaysengineer.org/2003/May/history.asp) January 8, 2015, at the [Wayback Machine](/source/Wayback_Machine) *IEEE-USA Today's Engineer*.

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1. ^ [***a***](#cite_ref-todaysengineer.org_19-0) [***b***](#cite_ref-todaysengineer.org_19-1) ["Twists and Turns in the Development of the Transistor"](https://web.archive.org/web/20150108082709/http://www.todaysengineer.org/2003/May/history.asp). Institute of Electrical and Electronics Engineers, Inc. Archived from [the original](http://www.todaysengineer.org/2003/May/history.asp) on January 8, 2015.

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1. ^ [***a***](#cite_ref-Guarnieri_1_26-0) [***b***](#cite_ref-Guarnieri_1_26-1) Guarnieri, M. (2017). "Seventy Years of Getting Transistorized". *IEEE Industrial Electronics Magazine*. **11** (4): 33–37. [doi](/source/Doi_(identifier)):[10.1109/MIE.2017.2757775](https://doi.org/10.1109%2FMIE.2017.2757775). [hdl](/source/Hdl_(identifier)):[11577/3257397](https://hdl.handle.net/11577%2F3257397). [S2CID](/source/S2CID_(identifier)) [38161381](https://api.semanticscholar.org/CorpusID:38161381).

1. **[^](#cite_ref-Lee_27-0)** Lee, Thomas H. (2003). ["The Design of CMOS Radio-Frequency Integrated Circuits"](https://web.archive.org/web/20211021005313/https://www.semanticscholar.org/paper/The-Design-of-CMOS-Radio-Frequency-Integrated-Ellis/c0018d231b4960f7a6c4f581b086212d7f8b0d15?p2df). *Soldering & Surface Mount Technology*. **16** (2). [Cambridge University Press](/source/Cambridge_University_Press). [doi](/source/Doi_(identifier)):[10.1108/ssmt.2004.21916bae.002](https://doi.org/10.1108%2Fssmt.2004.21916bae.002). [ISBN](/source/ISBN_(identifier)) [978-1-139-64377-1](https://en.wikipedia.org/wiki/Special:BookSources/978-1-139-64377-1). [S2CID](/source/S2CID_(identifier)) [108955928](https://api.semanticscholar.org/CorpusID:108955928). Archived from [the original](https://www.semanticscholar.org/paper/The-Design-of-CMOS-Radio-Frequency-Integrated-Ellis/c0018d231b4960f7a6c4f581b086212d7f8b0d15?p2df) on October 21, 2021.

1. **[^](#cite_ref-Puers_28-0)** Puers, Robert; Baldi, Livio; Voorde, Marcel Van de; Nooten, Sebastiaan E. van (2017). [*Nanoelectronics: Materials, Devices, Applications, 2 Volumes*](https://books.google.com/books?id=JOqVDgAAQBAJ&pg=PA14). [John Wiley & Sons](/source/John_Wiley_%26_Sons). p. 14. [ISBN](/source/ISBN_(identifier)) [978-3-527-34053-8](https://en.wikipedia.org/wiki/Special:BookSources/978-3-527-34053-8).

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1. **[^](#cite_ref-30)** [US 2673948](https://worldwide.espacenet.com/textdoc?DB=EPODOC&IDX=US2673948) H. F. Mataré / H. Welker / Westinghouse, "Crystal device for controlling electric currents by means of a solid semiconductor" French priority August 13, 1948

1. **[^](#cite_ref-31)** ["1948, The European Transistor Invention"](http://www.computerhistory.org/semiconductor/timeline/1948-European.html). Computer History Museum. [Archived](https://web.archive.org/web/20120929202704/http://www.computerhistory.org/semiconductor/timeline/1948-European.html) from the original on September 29, 2012.

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1. **[^](#cite_ref-36)** Electronics magazine, January 1954, Article "Electroplated Transistors Announced"

1. **[^](#cite_ref-37)** P. Mallery, *Transistors and Their Circuits in the 4A Toll Crossbar Switching System*, AIEE Transactions, September 1953, p.388

1. **[^](#cite_ref-38)** 1953 Foreign Commerce Weekly; Volume 49; pp.23

1. **[^](#cite_ref-39)** ["*Der deutsche Erfinder des Transistors – Nachrichten Welt Print – DIE WELT*"](https://www.welt.de/welt_print/article2721871/Der-deutsche-Erfinder-des-Transistors.html). *Die Welt*. Welt.de. November 23, 2011. [Archived](https://web.archive.org/web/20160515182422/http://www.welt.de/welt_print/article2721871/Der-deutsche-Erfinder-des-Transistors.html) from the original on May 15, 2016. Retrieved May 1, 2016.

1. **[^](#cite_ref-40)** ["Regency TR-1 Transistor Radio History"](http://www.regencytr1.com/). [Archived](https://web.archive.org/web/20041021040145/http://www.regencytr1.com/) from the original on October 21, 2004. Retrieved April 10, 2006.

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1. **[^](#cite_ref-43)** Wall Street Journal, "Chrysler Promises Car Radio With Transistors Instead of Tubes in '56", April 28, 1955, page 1

1. **[^](#cite_ref-44)** ["FCA North America - Historical Timeline 1950-1959"](https://web.archive.org/web/20150402062327/http://www.fcanorthamerica.com/company/Heritage/Pages/Chrysler-Heritage-1950.aspx). *www.fcanorthamerica.com*. Archived from [the original](http://www.fcanorthamerica.com/company/Heritage/Pages/Chrysler-Heritage-1950.aspx) on April 2, 2015. Retrieved December 5, 2017.

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1. **[^](#cite_ref-49)** Chelikowski, J. (2004) "Introduction: Silicon in all its Forms", p. 1 in *Silicon: evolution and future of a technology*. P. Siffert and E. F. Krimmel (eds.). Springer, [ISBN](/source/ISBN_(identifier)) [3-540-40546-1](https://en.wikipedia.org/wiki/Special:BookSources/3-540-40546-1).

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1. **[^](#cite_ref-51)** Lilienfeld, Julius Edgar, "Device for controlling electric current" [U.S. patent 1,900,018](https://patents.google.com/patent/US1900018) March 7, 1933 (filed in US March 28, 1928).

1. **[^](#cite_ref-52)** Grundmann, Marius (2010). *The Physics of Semiconductors*. Springer-Verlag. [ISBN](/source/ISBN_(identifier)) [978-3-642-13884-3](https://en.wikipedia.org/wiki/Special:BookSources/978-3-642-13884-3).

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1. **[^](#cite_ref-Moskowitz_55-0)** Moskowitz, Sanford L. (2016). [*Advanced Materials Innovation: Managing Global Technology in the 21st century*](https://books.google.com/books?id=2STRDAAAQBAJ&pg=PA168). [John Wiley & Sons](/source/John_Wiley_%26_Sons). p. 168. [ISBN](/source/ISBN_(identifier)) [978-0-470-50892-3](https://en.wikipedia.org/wiki/Special:BookSources/978-0-470-50892-3).

1. **[^](#cite_ref-56)** [US2802760A](https://patents.google.com/patent/US2802760A), Lincoln, Derick & Frosch, Carl J., "Oxidation of semiconductive surfaces for controlled diffusion", issued August 13, 1957

1. **[^](#cite_ref-57)** Ligenza, J. R.; Spitzer, W. G. (July 1, 1960). ["The mechanisms for silicon oxidation in steam and oxygen"](https://linkinghub.elsevier.com/retrieve/pii/0022369760902195). *Journal of Physics and Chemistry of Solids*. **14**: 131–136. [Bibcode](/source/Bibcode_(identifier)):[1960JPCS...14..131L](https://ui.adsabs.harvard.edu/abs/1960JPCS...14..131L). [doi](/source/Doi_(identifier)):[10.1016/0022-3697(60)90219-5](https://doi.org/10.1016%2F0022-3697%2860%2990219-5). [ISSN](/source/ISSN_(identifier)) [0022-3697](https://search.worldcat.org/issn/0022-3697).

1. **[^](#cite_ref-Deal2_58-0)** Deal, Bruce E. (1998). ["Highlights Of Silicon Thermal Oxidation Technology"](https://books.google.com/books?id=cr8FPGkiRS0C&pg=PA183). *Silicon materials science and technology*. [The Electrochemical Society](/source/The_Electrochemical_Society). p. 183. [ISBN](/source/ISBN_(identifier)) [978-1-56677-193-1](https://en.wikipedia.org/wiki/Special:BookSources/978-1-56677-193-1).

1. **[^](#cite_ref-59)** Lojek, Bo (2007). *History of Semiconductor Engineering*. Springer Science & Business Media. p. 322. [ISBN](/source/ISBN_(identifier)) [978-3-540-34258-8](https://en.wikipedia.org/wiki/Special:BookSources/978-3-540-34258-8).

1. **[^](#cite_ref-Bassett22_60-0)** Bassett, Ross Knox (2007). [*To the Digital Age: Research Labs, Start-up Companies, and the Rise of MOS Technology*](https://books.google.com/books?id=UUbB3d2UnaAC&pg=PA22). [Johns Hopkins University Press](/source/Johns_Hopkins_University_Press). pp. 22–23. [ISBN](/source/ISBN_(identifier)) [978-0-8018-8639-3](https://en.wikipedia.org/wiki/Special:BookSources/978-0-8018-8639-3).

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1. **[^](#cite_ref-122)** Rojas, Jhonathan P.; Torres Sevilla, Galo A.; Hussain, Muhammad M. (2013). ["Can We Build a Truly High Performance Computer Which is Flexible and Transparent?"](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3767948). *Scientific Reports*. **3** 2609. [Bibcode](/source/Bibcode_(identifier)):[2013NatSR...3.2609R](https://ui.adsabs.harvard.edu/abs/2013NatSR...3.2609R). [doi](/source/Doi_(identifier)):[10.1038/srep02609](https://doi.org/10.1038%2Fsrep02609). [PMC](/source/PMC_(identifier)) [3767948](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3767948). [PMID](/source/PMID_(identifier)) [24018904](https://pubmed.ncbi.nlm.nih.gov/24018904).

1. **[^](#cite_ref-123)** Zhang, Kan; Seo, Jung-Hun; Zhou, Weidong; Ma, Zhenqiang (2012). "Fast flexible electronics using transferrable [*sic*] silicon nanomembranes". *Journal of Physics D: Applied Physics*. **45** (14) 143001. [Bibcode](/source/Bibcode_(identifier)):[2012JPhD...45n3001Z](https://ui.adsabs.harvard.edu/abs/2012JPhD...45n3001Z). [doi](/source/Doi_(identifier)):[10.1088/0022-3727/45/14/143001](https://doi.org/10.1088%2F0022-3727%2F45%2F14%2F143001). [S2CID](/source/S2CID_(identifier)) [109292175](https://api.semanticscholar.org/CorpusID:109292175).

1. **[^](#cite_ref-124)** Sun, Dong-Ming; Timmermans, Marina Y.; Tian, Ying; Nasibulin, Albert G.; Kauppinen, Esko I.; Kishimoto, Shigeru; Mizutani, Takashi; Ohno, Yutaka (2011). "Flexible high-performance carbon nanotube integrated circuits". *Nature Nanotechnology*. **6** (3): 156–61. [Bibcode](/source/Bibcode_(identifier)):[2011NatNa...6..156S](https://ui.adsabs.harvard.edu/abs/2011NatNa...6..156S). [doi](/source/Doi_(identifier)):[10.1038/NNANO.2011.1](https://doi.org/10.1038%2FNNANO.2011.1). [PMID](/source/PMID_(identifier)) [21297625](https://pubmed.ncbi.nlm.nih.gov/21297625). [S2CID](/source/S2CID_(identifier)) [205446925](https://api.semanticscholar.org/CorpusID:205446925).

## Further reading

**Books**

- [Horowitz, Paul](/source/Paul_Horowitz) & Hill, Winfield (2015). [*The Art of Electronics*](/source/The_Art_of_Electronics) (3 ed.). Cambridge University Press. [ISBN](/source/ISBN_(identifier)) [978-0-521-80926-9](https://en.wikipedia.org/wiki/Special:BookSources/978-0-521-80926-9).{{[cite book](https://en.wikipedia.org/wiki/Template:Cite_book)}}: CS1 maint: multiple names: authors list ([link](https://en.wikipedia.org/wiki/Category:CS1_maint:_multiple_names:_authors_list))

- Amos SW, James MR (1999). *Principles of Transistor Circuits*. Butterworth-Heinemann. [ISBN](/source/ISBN_(identifier)) [978-0-7506-4427-3](https://en.wikipedia.org/wiki/Special:BookSources/978-0-7506-4427-3).

- Riordan, Michael & Hoddeson, Lillian (1998). *Crystal Fire*. W.W Norton & Company Limited. [ISBN](/source/ISBN_(identifier)) [978-0-393-31851-7](https://en.wikipedia.org/wiki/Special:BookSources/978-0-393-31851-7). The invention of the transistor & the birth of the information age

- Warnes, Lionel (1998). *Analogue and Digital Electronics*. Macmillan Press Ltd. [ISBN](/source/ISBN_(identifier)) [978-0-333-65820-8](https://en.wikipedia.org/wiki/Special:BookSources/978-0-333-65820-8).

- *The Power Transistor – Temperature and Heat Transfer*; 1st Ed; John McWane, Dana Roberts, Malcom Smith; McGraw-Hill; 82 pages; 1975; [ISBN](/source/ISBN_(identifier)) [978-0-07-001729-0](https://en.wikipedia.org/wiki/Special:BookSources/978-0-07-001729-0). [(archive)](https://archive.org/details/ThePowerTransistor/)

- *Transistor Circuit Analysis – Theory and Solutions to 235 Problems*; 2nd Ed; Alfred Gronner; Simon and Schuster; 244 pages; 1970. [(archive)](https://archive.org/details/TransistorCircuitAnalysis/)

- *Transistor Physics and Circuits*; R.L. Riddle and M.P. Ristenbatt; Prentice-Hall; 1957.

**Periodicals**

- Michael Riordan (2005). ["How Europe Missed the Transistor"](https://web.archive.org/web/20080214002109/http://www.spectrum.ieee.org/print/2155). *IEEE Spectrum*. **42** (11): 52–57. [doi](/source/Doi_(identifier)):[10.1109/MSPEC.2005.1526906](https://doi.org/10.1109%2FMSPEC.2005.1526906). [S2CID](/source/S2CID_(identifier)) [34953819](https://api.semanticscholar.org/CorpusID:34953819). Archived from [the original](https://spectrum.ieee.org/print/2155) on February 14, 2008.

- ["Herbert F. Mataré, An Inventor of the Transistor has his moment"](https://web.archive.org/web/20090623050755/http://www.mindfully.org/Technology/2003/Transistor-Matare-Inventor24feb03.htm). *The New York Times*. February 24, 2003. Archived from [the original](http://www.mindfully.org/Technology/2003/Transistor-Matare-Inventor24feb03.htm) on June 23, 2009.

- Bacon, W. Stevenson (1968). ["The Transistor's 20th Anniversary: How Germanium And A Bit of Wire Changed The World"](https://books.google.com/books?id=mykDAAAAMBAJ). *Popular Science*. **192** (6): 80–84. [ISSN](/source/ISSN_(identifier)) [0161-7370](https://search.worldcat.org/issn/0161-7370).

**Databooks**

- [Discrete Databook](https://archive.org/details/bitsavers_fairchilddldDiscreteDataBook_35122751); 1985; Fairchild (now ON Semiconductor)

- [Small-Signal Semiconductors Databook](https://archive.org/details/bitsavers_motoroladaSmallSignalSemiconductors_75896318/), 1987; Motorola (now ON semiconductor)

- [Discrete Power Devices Databook](https://archive.org/details/bitsavers_sgsdataBooDevices5ed_46325378); 1982; SGS (now STMicroelectronics)

- [Discrete Databook](https://archive.org/details/NationalSemiconductor-DiscreteDatabook1978OCR); 1978; National Semiconductor (now Texas Instruments)

## External links

Wikimedia Commons has media related to ***[Transistors](https://commons.wikimedia.org/wiki/Category:Transistors)*** and ***[Transistors (SMD)](https://commons.wikimedia.org/wiki/Category:Transistors_(SMD))***.

Wikibooks has a book on the topic of: ***[Transistors](https://en.wikibooks.org/wiki/Transistors)***

- [BBC: Building the digital age](http://news.bbc.co.uk/2/hi/technology/7091190.stm) photo history of transistors

- [The Bell Systems Memorial on Transistors](https://web.archive.org/web/20070928041118/http://www.porticus.org/bell/belllabs_transistor.html)

- [*IEEE Global History Network, The Transistor and Portable Electronics*](https://www.ieeeghn.org/wiki/index.php/The_Transistor_and_Portable_Electronics) [Archived](https://web.archive.org/web/20150214010452/http://www.ieeeghn.org/wiki/index.php/The_Transistor_and_Portable_Electronics) February 14, 2015, at the [Wayback Machine](/source/Wayback_Machine). All about the history of transistors and integrated circuits.

- [*This Month in Physics History: November 17 to December 23, 1947: Invention of the First Transistor*](https://www.aps.org/publications/apsnews/200011/history.cfm). From the [American Physical Society](/source/American_Physical_Society)

- [Transistor | Definition & Uses | Britannica](https://www.britannica.com/technology/transistor) "Transistor" at *[Encyclopædia Britannica](/source/Encyclop%C3%A6dia_Britannica)*

v t e Electronic components Semiconductor devices MOS transistors Transistor NMOS PMOS BiCMOS BioFET Chemical field-effect transistor (ChemFET) Complementary MOS (CMOS) Depletion-load NMOS Fin field-effect transistor (FinFET) Floating-gate MOSFET (FGMOS) Insulated-gate bipolar transistor (IGBT) ISFET LDMOS MOS field-effect transistor (MOSFET) Multi-gate field-effect transistor (MuGFET) Power MOSFET Thin-film transistor (TFT) VMOS UMOS QFET Tunnel field-effect transistor (TFET) High-electron-mobility transistor (HEMT) RF CMOS Native transistor Other transistors Bipolar junction transistor (BJT) Darlington transistor Diffused junction transistor Field-effect transistor (FET) Junction Gate FET (JFET) Organic FET (OFET) Light-emitting transistor (LET) Organic LET (OLET) Pentode transistor Point-contact transistor Programmable unijunction transistor (PUT) Static induction transistor (SIT) Tetrode transistor Nanoscale vacuum-channel transistor (NVCT) Single-electron transistor (SET) Heterojunction bipolar transistor (HBT) MESFET Heterostructure-emitter bipolar transistor (HEBT) ITFET Avalanche transistor Junctionless nanowire transistor (JLNT) Schottky transistor Spin transistor Ballistic collection transistor Ballistic deflection transistor (BDT) Drift-field transistor Organic electrochemical transistor (OECT) Spacistor Surface-barrier transistor Synaptic transistor Oxide thin-film transistor NOMFET Grown-junction transistor EOSFET Alloy-junction transistor Fe FET DNA field-effect transistor (DNAFET) Diodes Avalanche diode Shockley diode Selenium rectifier Fast diode Single-photon avalanche diode (SPAD) Constant-current diode (CLD, CRD) Gunn diode Varicap IMPATT diode Metal–insulator–metal diode (MIM diode) Transient-voltage-suppression diode (TVS diode) Laser diode (LD) Light-emitting diode (LED) Organic light-emitting diode (OLED) Photodiode PIN diode p–n diode Tunnel diode Avalanche photodiode (APD) Solar cell Multi-junction solar cell (MJ) Hybrid solar cell Schottky junction solar cell Plasmonic solar cell Heterojunction solar cell (HJT) Schottky diode Step recovery diode (SRD) Zener diode Resonant-tunneling diode (RTD) Photoreflector Backward diode Geometric diode Lr-diode Chua's diode BARITT diode Stabistor Phosphorescent organic light-emitting diode (PHOLED) Thin-film diode Superluminescent diode (SLD) Josephson diode Hole accumulation diode (HAD) Silicon photomultiplier (SiPM) Metal rectifier Bifacial solar cells (BSC) Integrated Circuits Hybrid integrated circuit (HIC) Mixed-signal integrated circuit MOS integrated circuit (MOS IC) Three-dimensional integrated circuit (3D IC) Photonic integrated circuit (PIC) Application-specific integrated circuit (ASIC) Field-programmable gate array (FPGA) System on a chip (SoC) Other devices DIAC Heterostructure barrier varactor Light emitting capacitor (LEC) Memistor Memristor Memtransistor Memory cell Metal-oxide varistor (MOV) Organic semiconductor Photodetector Silicon controlled rectifier (SCR) Solaristor Static induction thyristor (SITh) Thyristor Trancitor TRIAC Varicap Vertical-cavity surface-emitting laser (VCSEL) Gate turn-off thyristor (GTO) Integrated gate-commutated thyristor (IGCT) Unijunction transistor (UJT) Quantum-cascade laser (QCL) Photoresistor Quantum dot display Quantum dot solar cell Photoelectrochemical cell Dye-sensitized solar cell Plasmonic solar cell Quantum dot laser Quadrac Interband cascade laser (ICL) Oscillistor MOS composite static induction thyristor (CSMT) MOS-controlled thyristor (MCT) Resistive opto-isolator (RO) Emitter turn off thyristor (ETO) Trisil Quantum well infrared photodetector (QWIP) Quantum cascade detector (QCD) Resonant-cavity-enhanced photo detector (RCE) Golay cell Hybrid pixel detector Semiconductor detector Voltage regulators Linear regulator Low-dropout regulator Switching regulator Buck Boost Buck–boost Split-pi Ćuk SEPIC Charge pump Switched capacitor Vacuum tubes Standard Acorn tube Audion Beam tetrode Barretter Compactron Diode Fleming valve Neutron tube Nonode Nuvistor Pentagrid (Hexode, Heptode, Octode) Pentode Photomultiplier (PMT) Phototube Tetrode Triode X-ray tube Double diode triode Additron tube Computron tube Micropup RF Backward-wave oscillator (BWO) Cavity magnetron Crossed-field amplifier (CFA) Gyrotron Inductive output tube (IOT) Klystron Maser Sutton tube Traveling-wave tube (TWT) Vircator Cathode ray tubes Beam deflection tube Charactron Iconoscope Magic eye tube Monoscope Selectron tube Storage tube Trochotron Video camera tube Williams tube Gas-filled tubes Crossatron Dekatron Ignitron Krytron Mercury-arc valve Nixie tube Thyratron Trigatron Voltage-regulator tube Geiger–Müller tube Wire chamber Neon lamp Adjustable Potentiometer digital Variable capacitor Varicap Passive Connector audio and video electrical power RF Ferrite Antifuse Fuse resettable eFuse Resistor Switch Thermistor Varistor Reactive Capacitor types Ceramic resonator Crystal oscillator Inductor Relay reed relay mercury relay Other devices Hall effect sensor SQUID Spin valve Magnetic tunnel junction (MTJ) Planar Hall sensor ggNMOS

v t e Digital electronics Components Transistor Resistor Inductor Capacitor Printed electronics Printed circuit board Electronic circuit Flip-flop Memory cell Combinational logic Sequential logic Logic gate Boolean circuit Integrated circuit (IC) Hybrid integrated circuit (HIC) Mixed-signal integrated circuit Three-dimensional integrated circuit (3D IC) Emitter-coupled logic (ECL) Erasable programmable logic device (EPLD) Macrocell array Programmable logic array (PLA) Programmable logic device (PLD) Programmable Array Logic (PAL) Generic Array Logic (GAL) Complex programmable logic device (CPLD) Field-programmable gate array (FPGA) Field-programmable object array (FPOA) Application-specific integrated circuit (ASIC) Tensor Processing Unit (TPU) Theory Digital signal Boolean algebra Logic synthesis Logic in computer science Computer architecture Digital signal Digital signal processing Circuit minimization Switching circuit theory Gate equivalent Design Logic synthesis Place and route Placement Routing Transaction-level modeling Register-transfer level Hardware description language High-level synthesis Formal equivalence checking Synchronous logic Asynchronous logic Finite-state machine Hierarchical state machine Applications Computer hardware Hardware acceleration Digital audio radio Digital photography Digital telephone Digital video cinematography television Electronic literature Design issues Metastability Runt pulse

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Adapted from the Wikipedia article [Transistor](https://en.wikipedia.org/wiki/Transistor) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Transistor?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.