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Transistor

technology Maturity 9-11

A tiny part helps machines work.

Replica-of-first-transistor.jpg
Replica-of-first-transistor.jpg
It can turn power on or off. It can also make a small sound loud. This helps your radio play music. It is in many things you use. Do you see one in your toys?

42 words

A transistor is a tiny part for machines.

Replica-of-first-transistor.jpg
Replica-of-first-transistor.jpg
It can act like a switch. It can also make a signal much stronger.
MOSFET Structure.png
MOSFET Structure.png

To work, it uses electricity. A small amount of power controls a larger amount. This helps the machine work better.

Most are made from silicon. This is a very pure material.

2N2222A NPN Transsitor.jpg
2N2222A NPN Transsitor.jpg

These parts are in many things. You can find them in radios and computers. They even help cars work. They are very important tools.

83 words

A transistor is a tiny part used in electronics.

Replica-of-first-transistor.jpg
Replica-of-first-transistor.jpg
It is a building block for many machines. It can act as a switch. It can also work as an amplifier. An amplifier makes a signal much stronger.
MOSFET Structure.png
MOSFET Structure.png

To work, a transistor uses electricity. A small amount of power controls a larger amount. This happens through its terminals, or connection points. Most transistors are made from pure silicon. Some use a material called germanium.

2N2222A NPN Transsitor.jpg
2N2222A NPN Transsitor.jpg

Scientists first made a working transistor in 1947. John Bardeen, Walter Brattain, and William Shockley did this at Bell Labs. They won the Nobel Prize for their work. Later, a common type called a MOSFET was made. This type is used in many modern tools. Transistors helped make radios and computers much smaller. They also helped make them cheaper. You can even find them in car radios. They changed how we use technology every day.

154 words

A transistor is a tiny part used in modern electronics.

Transistor symbol npn no circle.svg
Transistor symbol npn no circle.svg
It acts as a basic building block for almost all electronic machines. One important job of a transistor is to act as an amplifier. An amplifier takes a small signal and makes it much stronger.
Transistor as switch.svg
Transistor as switch.svg
Another job is to act as a switch for electrical signals. This allows electricity to flow or stop as needed. Because they are so small, many are tucked inside integrated circuits. They are considered one of the greatest inventions of the 20th century.

How does this little device work?

MOSFET Structure.png
MOSFET Structure.png
A transistor has at least three terminals, which are connection points. You apply a small voltage or current to one pair of these terminals. This action then controls the current flowing through a different pair. This is how it controls power or amplifies a signal. If the output power is higher than the input power, the signal grows. Most transistors are made from very pure silicon. Some are made from a material called germanium. Some devices use one kind of charge carrier, while others use two.

The idea for these devices came long before they actually worked.

Julius Edgar Lilienfeld (1881-1963).jpg
Julius Edgar Lilienfeld (1881-1963).jpg
In 1925, a physicist named Julius Edgar Lilienfeld proposed a field-effect transistor. He filed patents in Canada and the United States in the 1920s. However, he did not build a working model at that time. In 1934, an inventor named Oskar Heil patented a similar device in Europe. It took many years to make the right materials to build them. Scientists needed much higher quality semiconductor materials to make the dream real.

The first working device was finally made in 1947.

Replica-of-first-transistor.jpg
Replica-of-first-transistor.jpg
Physicists John Bardeen and Walter Brattain built a point-contact transistor at Bell Labs. They used two gold contacts on a crystal of germanium.
Bardeen Shockley Brattain 1948.JPG
Bardeen Shockley Brattain 1948.JPG
William Shockley also worked with them and later invented the bipolar junction transistor. These three men shared the Nobel Prize in Physics in 1956. Between 1955 and 1960, Bell Labs also invented the MOSFET. This is the most widely used type of transistor today.

Transistors changed the world by making technology much smaller.

Philco Surface Barrier transistor=1953.jpg
Philco Surface Barrier transistor=1953.jpg
Before transistors, machines used vacuum tubes which were large and used much power. Transistors are much smaller and require less power to work. They allowed for the creation of tiny pocket radios like the Regency TR-1.
1957(Figure 9)-Gate oxide transistor by Frosch and Derrick.png
1957(Figure 9)-Gate oxide transistor by Frosch and Derrick.png
They also paved the way for calculators and computers. You can even find them in car radios, like the Mopar model from 1956. Today, they are in almost every electronic device you use.

444 words

A transistor is a semiconductor device used to amplify or switch electrical signals and power. It serves as one of the fundamental building blocks of all modern electronics. Because they are essential to almost every electronic device, many consider the transistor one of the greatest inventions of the 20th century.

Transistor symbol npn no circle.svg
Transistor symbol npn no circle.svg
These devices are usually composed of semiconductor material, such as very pure silicon or germanium. A transistor typically has at least three terminals used for connection to an electronic circuit. By applying a voltage or current to one pair of terminals, a user can control the current flowing through another pair.

The mechanism of a transistor relies on this control of electrical flow. When the controlled output power is higher than the controlling input power, the device acts as an amplifier. This means it takes a small signal and makes it much stronger.

Transistor as switch.svg
Transistor as switch.svg
If the device is used to stop or start the flow of electricity, it acts as a switch. This process happens within the semiconductor material. Some transistors, known as bipolar junction transistors, use two kinds of charge carriers to move electricity. Other types, like field-effect transistors, may only use one kind of charge carrier.
MOSFET Structure.png
MOSFET Structure.png

There are several distinct types of transistors used in technology today. The metal–oxide–semiconductor field-effect transistor, or MOSFET, is the most widely used type.

Threshold formation nowatermark.gif
Threshold formation nowatermark.gif
Another major category is the field-effect transistor (FET), which uses an electric field to control current. Within the FET family, there are specific versions like the junction field-effect transistor (JFET) and the insulated-gate field-effect transistor (IGFET). Bipolar transistors are another group, which includes the point-contact transistor and the bipolar junction transistor. While some transistors are packaged as single, individual components, many more are built in miniature form inside integrated circuits.

The history of the transistor began with theoretical ideas before working models existed. In 1925, physicist Julius Edgar Lilienfeld proposed the concept of a field-effect transistor (FET).

Julius Edgar Lilienfeld (1881-1963).jpg
Julius Edgar Lilienfeld (1881-1963).jpg
He filed patents in Canada and the United States, but he did not publish research or show a working prototype. In 1934, Oskar Heil patented a similar device in Europe. It was not possible to build these devices in the 1920s because high-quality semiconductor materials were not yet available. The first working device, a point-contact transistor, was finally invented in 1947.
Replica-of-first-transistor.jpg
Replica-of-first-transistor.jpg
This was achieved by John Bardeen and Walter Brattain at Bell Labs using germanium crystals.

Discovery at Bell Labs continued to shape the field through the late 1940s and 1950s.

Bardeen Shockley Brattain 1948.JPG
Bardeen Shockley Brattain 1948.JPG
William Shockley, the leader of the Solid State Physics Group, worked to expand knowledge of semiconductors after seeing the success of the point-contact model. He later invented the bipolar junction transistor in 1948. In 1950, chemists Gordon Teal and Morgan Sparks successfully produced a working bipolar NPN junction amplifying germanium transistor.
2N2222A NPN Transsitor.jpg
2N2222A NPN Transsitor.jpg
The first silicon transistor was developed by Morris Tanenbaum at Bell Labs in 1954. Shortly after, Texas Instruments announced the first production commercial silicon transistor in May 1954. For their work on semiconductors and the transistor effect, Bardeen, Brattain, and Shockley shared the 1956 Nobel Prize in Physics.

The significance of the transistor is seen in how it replaced older technology. Before transistors, electronics relied on vacuum tubes, such as the thermionic triode invented in 1907.

Philco Surface Barrier transistor=1953.jpg
Philco Surface Barrier transistor=1953.jpg
Vacuum tubes were fragile and consumed a large amount of power. Transistors are generally smaller and require much less power to operate. This shift allowed for much smaller and cheaper devices. For example, the first production-model pocket transistor radio, the Regency TR-1, was released in October 1954. Later, the Sony TR-63 became the first mass-produced transistor radio, selling seven million units worldwide by the mid-1960s.

Transistors revolutionized many different industries and connected to various technological fields. They paved the way for modern calculators, computers, and advanced telecommunications. In 1953, AT&T used transistors in the No. 4A Toll Crossbar Switching System for telephone routing. The automotive industry also adopted the technology, with Chrysler and Philco announcing the first production all-transistor car radio in 1955.

1957(Figure 9)-Gate oxide transistor by Frosch and Derrick.png
1957(Figure 9)-Gate oxide transistor by Frosch and Derrick.png
Because they can be made so small, they are now embedded in almost all modern electronic systems. This transition from bulky tubes to tiny semiconductors changed how the world uses technology.

719 words
🖼️ Images & Media (28)
File:Transistor symbol npn no circle.svg
Transistor symbol npn no circle.svg
File:Transistor symbol pnp no circle.svg
Transistor symbol pnp no circle.svg
File:MOSFET Structure.png
MOSFET Structure.png
File:Julius Edgar Lilienfeld (1881-1963).jpg
Julius Edgar Lilienfeld (1881-1963).jpg
File:Bardeen Shockley Brattain 1948.JPG
Bardeen Shockley Brattain 1948.JPG
File:Replica-of-first-transistor.jpg
Replica-of-first-transistor.jpg
File:Philco Surface Barrier transistor=1953.jpg
Philco Surface Barrier transistor=1953.jpg
File:1957(Figure_9)-Gate_oxide_transistor_by_Frosch_and_Derrick.png
1957(Figure_9)-Gate_oxide_transistor_by_Fr...
File:Transistor Simple Circuit Diagram with NPN Labels.svg
Transistor Simple Circuit Diagram with...
File:Transistor as switch.svg
Transistor as switch.svg
File:NPN common emitter AC.svg
NPN common emitter AC.svg
File:BJT PNP symbol.svg
BJT PNP symbol.svg

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