1947/48 John Bardeen, Walter Brattain & Wiliam Shockley The Transistor

The History of the Transistor - John Bardeen, Walter Brattain, and William Shockley

The transistor is an influential invention that changed the course of history for computers. The first generation of computers used vacuum tubes; the second generation of computers used transistors; the third generation of computers used integrated circuits; and the fourth generation of computers used microprocessors.

John Bardeen, William Shockley, and Walter Brattain, scientists at the Bell Telephone Laboratories in Murray Hill, New Jersey, were researching the behavior of crystals (germanium) as semi-conductors in an attempt to replace vacuum tubes as mechanical relays in telecommunications. The vacuum tube, used to amplify music and voice, made long-distance calling practical, but the tubes consumed power, created heat and burned out rapidly, requiring high maintenance.

The team's research was about to come to a fruitless end when a last attempt to try a purer substance as a contact point lead to the invention of the "point-contact" transistor amplifier. In 1956, the team received the Nobel Prize in Physics for the invention of the transistor.

A transistor is a device composed of semi-conductor material that can both conduct and insulate (e.g. germanium and silicon). Transistors switch and modulate electronic current. Before transistors, digital circuits were composed of vacuum tubes. [Read the ENIAC story to learn all about the disadvantages of vacuum tubes in computers.] The transistor was the first device designed to act as both a transmitter, converting sound waves into electronic waves, and resistor, controlling electronic current. The name transistor comes from the 'trans' of transmitter and 'sistor' of resistor.

John Bardeen and Walter Brattain took out a patent for their transistor. William Shockley applied for a patent for the transistor effect and a transistor amplifier. Transistors transformed the world of electronics and had a huge impact on computer design. Transistors made of semiconductors replaced tubes in the construction of computers. By replacing bulky and unreliable vacuum tubes with transistors, computers could now perform the same functions, using less power and space.