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. Most transistors are made from very pure silicon, and some from germanium, but certain other semiconductor materials are sometimes used. Transistors revolutionized the field of electronics and paved the way for smaller and cheaper radios, calculators, computers, and other electronic devices. The most widely used type of transistor is the metal–oxide–semiconductor field-effect transistor (MOSFET), invented by Mohamed Atalla and Dawon Kahng at Bell Labs in 1959. The first working device was a point-contact transistor invented in 1947 by physicists John Bardeen, Walter Brattain, and William Shockley at Bell Labs the three shared the 1956 Nobel Prize in Physics for their achievement. Physicist Julius Edgar Lilienfeld proposed the concept of a field-effect transistor (FET) in 1926, but it was not possible to construct a working device at that time. Because transistors are the key active components in practically all modern electronics, many people consider them one of the 20th century's greatest inventions. Some transistors are packaged individually, but many more in miniature form are found embedded in integrated circuits. Because the controlled (output) power can be higher than the controlling (input) power, a transistor can amplify a signal. A voltage or current applied to one pair of the transistor's terminals controls the current through another pair of terminals. It is composed of semiconductor material, usually with at least three terminals for connection to an electronic circuit. It is one of the basic building blocks of modern electronics. The gate is separated from the body by an insulating layer (white).Ī transistor is a semiconductor device used to amplify or switch electrical signals and power. Size comparison of bipolar junction transistor packages, including (from left to right): SOT-23, TO-92, TO-126, and TO-3 Metal–oxide–semiconductor field-effect transistor (MOSFET), showing gate (G), body (B), source (S) and drain (D) terminals. For other uses, see Transistor (disambiguation).

Transistor gate charge