Transistor

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 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.

History

The

From November 17 to December 23, 1947,

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.^[30] They were made by etching depressions into an n-type germanium base from both sides with jets of indium(III) sulfate until it was a few ten-thousandths of an inch thick. Indium electroplated into the depressions formed the collector and emitter.^[31][32]

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.

The first prototype pocket

The first production all-transistor car radio 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.^[39][40]

The

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.^[11][47] The FET concept was later also theorized by engineer Oskar Heil in the 1930s and by William Shockley in the 1940s.

In 1945

In 1948, Bardeen patented the progenitor of MOSFET, an insulated-gate FET (IGFET) with an inversion layer. Bardeen's patent, and the concept of an inversion layer, forms the basis of CMOS technology today.[50]

MOSFET (MOS transistor)

Mohamed Atalla (left) and Dawon Kahng (right) invented the MOSFET

(MOS transistor) at Bell Labs in 1959.

In the early years of the

surface state barrier that prevented the external electric field from penetrating the material.^[51]

In 1957, Bell Labs engineer

metal–oxide–semiconductor (MOS) process,^[52]

and proposed that it could be used to build the first working silicon FET.

Atalla and his Korean colleague

high-density integrated circuits,^[7] allowing the integration of more than 10,000 transistors in a single IC.^[58]

FinFET (fin field-effect transistor), 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.^[63][64]

Importance

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

The invention of the first transistor at Bell Labs was named an

junction transistor in 1948 and the MOSFET in 1959.^[66]

The MOSFET is by far the most widely used transistor, in applications ranging from

US Patent and Trademark Office calls it a "groundbreaking invention that transformed life and culture around the world".^[67] 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 the most numerously produced artificial objects in history, with more than 13 sextillion manufactured by 2018.^[72]

Although several companies each produce over a billion individually packaged (known as

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.^[74] Transistors are often organized into logic gates in microprocessors to perform computation.^[75]

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 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.

Simplified operation

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 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.^[76]

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

• A
  bipolar junction transistor (BJT)
  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) has terminals labeled gate, source and drain. A voltage at the gate can control a current between source and drain.^[77]

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.^[77]

Transistor as a switch

Transistors are commonly used in

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 the current switched, the voltage handled, and the switching speed, characterized by the rise and fall times.^[77]

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.[77]

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.^[78]

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.^[77] The base resistor value is calculated from the supply voltage, transistor C-E junction voltage drop, collector current, and amplification factor beta.^[79]

Transistor as an amplifier

The

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.^[77]

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

From

sound reproduction, radio transmission, and 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.^[77]

Modern transistor audio amplifiers of up to a few hundred watts are common and relatively inexpensive.

Comparison with vacuum tubes

Before transistors were developed, vacuum (electron) tubes (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
  and depletion.
• Very small size and weight, reducing equipment size.
• Large numbers of extremely small transistors can be manufactured as a single 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 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
  travelling wave tubes
  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 in handling. Vacuum tubes are electrically much more rugged.
• They are sensitive to radiation and cosmic rays (special radiation-hardened chips are used for spacecraft devices).
• In audio applications, transistors lack the lower-harmonic distortion – the so-called tube sound – which is characteristic of vacuum tubes, and is preferred by some.^[80]

Types

Classification

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	PNP		P-channel
	NPN		N-channel
BJT		JFET

BJT and JFET symbols

			P-channel
			N-channel
MOSFET enh		MOSFET dep

MOSFET symbols

Transistors are categorized by

• Structure:
  which?
  ].
• Semiconductor material (dopants):
  • The
    metalloids; germanium (first used in 1947) and silicon (first used in 1954)—in amorphous, polycrystalline and monocrystalline
    form.
  • The compounds gallium arsenide (1966) and silicon carbide (1997).
  • The
    silicon-germanium
    (1989)
  • The
    allotrope of carbon graphene (research ongoing since 2004), etc. (see Semiconductor material
    ).
• PNP
  (BJTs), N-channel, P-channel (FETs).
• Maximum power rating: low, medium, high.
• Maximum operating frequency: low, medium, high, radio (RF), 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—the frequency at which the transistor yields unity voltage gain)
• Application: switch, general purpose, audio, high voltage, super-beta, matched pair.
• Physical packaging: through-hole metal, through-hole plastic, surface mount, ball grid array, power modules (see Packaging).
• Amplification factor
  transistor beta)^[81] or g_m (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.[82]

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

Mnemonics

Convenient

electrical symbol) involves the direction of the arrow. For the BJT

, on an n-p-n transistor symbol, the arrow will "Not Point iN". On a p-n-p transistor symbol, the arrow "Points iN Proudly". 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

See also: JFET

FET

and its I_d-V_g 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, 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 (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)², where V_T is the threshold voltage at which drain current begins)

65 nm technology node.^[84]

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, 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.

Metal–semiconductor FETs (

reverse biased p–n junction is replaced by a metal–semiconductor 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

The metal–oxide–semiconductor field-effect transistor (

signals. The MOSFET is by far the most common transistor, and the basic building block of most modern electronics.^[71] The MOSFET accounts for 99.9% of all transistors in the world.^[85]

Bipolar junction transistor (BJT)

Main article: Bipolar junction transistor

Bipolar transistors are so named because they conduct by using both majority and minority carriers. 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: 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 because the currents at the emitter and collector are controllable by a relatively small base current.^[86] In an n–p–n transistor operating in the active region, the emitter-base junction is forward-biased (electrons and holes 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. As well, as the base is lightly doped (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.^[86] 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

Ebers-Moll model. Because of this exponential relationship, the BJT has a higher 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

.

Usage of MOSFETs and BJTs

The

power electronic applications in the 1980s. In integrated circuits

, 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

For early bipolar transistors, see Bipolar junction transistor § Bipolar transistors.

• Field-effect transistor (FET):
  • Metal–oxide–semiconductor field-effect transistor
    (MOSFET), where the gate is insulated by a shallow layer of insulator
    • p-type MOS (PMOS)
    • n-type MOS (NMOS)
    • complementary MOS (CMOS)
      • radiofrequency
        amplification, reception
    • Multi-gate field-effect transistor
      (MuGFET)
      • 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 (TFT), used in LCD and OLED displays, types include amorphous silicon, LTPS, LTPO and IGZO transistors
    • non-volatile storage
    • Power MOSFET, for power electronics
      • lateral diffused MOS (LDMOS)
  • Carbon nanotube field-effect transistor (CNFET, CNTFET), where the channel material is replaced by a carbon nanotube
  • Ferroelectric field-effect transistor (Fe FET), uses ferroelectric materials
  • Junction gate field-effect transistor
    (JFET), where the gate is insulated by a reverse-biased p–n junction
  • Metal–semiconductor field-effect transistor
    (MESFET), similar to JFET with a Schottky junction instead of a p–n junction
    • 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
    (ITFET)
  • Fast-reverse epitaxial diode field-effect transistor
    (FREDFET)
  • Organic field-effect transistor (OFET), in which the semiconductor is an organic compound
  • Ballistic transistor (disambiguation)
  • FETs used to sense the environment
    • Ion-sensitive field-effect transistor
      (ISFET), to measure ion concentrations in solution,
    • Electrolyte–oxide–semiconductor field-effect transistor (EOSFET), neurochip
      ,
    • Deoxyribonucleic acid field-effect transistor
      (DNAFET).
    • Field-effect transistor-based biosensor (Bio-FET)
• Bipolar junction transistor (BJT):
  • Heterojunction bipolar transistor, up to several hundred GHz, common in modern ultrafast and RF circuits
  • Schottky transistor
  • avalanche transistor

  • large-scale integration because this particular example is intended for power applications.

    Darlington transistors

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 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. Dual-gate field-effect transistors 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 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.

Japanese Industrial Standard (JIS)

In Japan, the JIS semiconductor designation (|JIS-C-7012), labels transistor devices starting with 2S,^[102] 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.

European Electronic Component Manufacturers Association (EECA)

The European Electronic Component Manufacturers Association (EECA) uses a numbering scheme that was inherited from 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^[103]) or other codes may follow to show gain (e.g. BC327-25) or voltage rating (e.g. BUK854-800A^[104]). The more common prefixes are:

Proprietary

Manufacturers of devices may have their proprietary numbering system, for example

Military part numbers sometimes are assigned their codes, such as the British Military CV Naming System.

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^[105][106] which is also assigned the CV number: CV7763^[107]

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, the other the higher-powered 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 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

The first BJTs were made from

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.^[108] In some circuits special compensating elements (sensistors) 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

1. Its maximum temperature is limited.
2. It has relatively high leakage current.
3. It cannot withstand high voltages.
4. 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

Maximum 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. This is included in the table because some silicon power IGFETs have a parasitic 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

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

Transistors come in many different semiconductor packages (see image). The two main categories are through-hole (or leaded), and surface-mount, also known as surface-mount device (SMD). The ball grid array (BGA) 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 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.

Researchers have made several kinds of flexible transistors, including organic field-effect transistors.^{[110][111][112]} Flexible transistors are useful in some kinds of flexible displays and other flexible electronics.

See also

References

Further reading

Books

• ISBN 978-0521809269.{{cite book}}: CS1 maint: multiple names: authors list (link
  )
• Amos SW, James MR (1999). Principles of Transistor Circuits. Butterworth-Heinemann.
  ISBN 978-0-7506-4427-3
  .
• Riordan, Michael & Hoddeson, Lillian (1998). Crystal Fire. W.W Norton & Company Limited.
  ISBN 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 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 978-0-07-001729-0. (archive)
• Transistor Circuit Analysis - Theory and Solutions to 235 Problems; 2nd Ed; Alfred Gronner; Simon and Schuster; 244 pages; 1970. (archive)
• Transistor Physics and Circuits; R.L. Riddle and M.P. Ristenbatt; Prentice-Hall; 1957.

Periodicals

• Michael Riordan (2005). "How Europe Missed the Transistor". IEEE Spectrum. 42 (11): 52–57.
  S2CID 34953819. Archived from the original
  on February 14, 2008.
• "Herbert F. Mataré, An Inventor of the Transistor has his moment". The New York Times. February 24, 2003. Archived from the original on June 23, 2009.
• Bacon, W. Stevenson (1968). "The Transistor's 20th Anniversary: How Germanium And A Bit of Wire Changed The World". Popular Science. 192 (6): 80–84.
  ISSN 0161-7370
  .

Databooks

• Discrete Databook; 1985; Fairchild (now ON Semiconductor)
• Small-Signal Semiconductors Databook, 1987; Motorola (now ON semiconductor)
• Discrete Power Devices Databook; 1982; SGS (now STMicroelectronics)
• Discrete Databook; 1978; National Semiconductor (now Texas Instruments)

External links

Wikimedia Commons has media related to Transistors and Transistors (SMD).

Wikibooks has a book on the topic of: Transistors

• BBC: Building the digital age photo history of transistors
• The Bell Systems Memorial on Transistors
• IEEE Global History Network, The Transistor and Portable Electronics. 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. From the American Physical Society
• Transistor | Definition & Uses | Britannica "Transistor" at Encyclopædia Britannica