The Transistor

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The first transistor (1947) Bell Labs

The Transistor (1953-1964)

"The transistor was probably the most important invention of the 20th Century, and the story behind the invention is one of clashing egos and top secret research." – Transistorized!, PBS

image of an RCA Point Contact Germanium Transistor

RCA Point Contact Transistor (1953)

The transistor is the fundamental building block of all modern electronic devices, and is found throughout modern electronic systems. Following its release in the early 1950s the transistor revolutionized the field of electronics, and paved the way for smaller and cheaper radios, calculators, and computers, amongst other things.

The transistor is the key active component in practically all modern electronics, and is considered by many to be one of the greatest inventions of the twentieth century.

A transistor is a semiconductor device, commonly used as an amplifier or an electrically controlled switch. The transistor is the fundamental building block of the circuitry in computers, cellular phones, and all other modern electronic devices.

History of the Transistor

The transistor was a crucial element in the development of better performing and more accurate electronic devices. Transistors, which are used to amplify and control electrical current, have played an important role in computing, radio, TV, and even space travel.

The Need for the Transistor

The role of the transistor in the development of electronic devices is similar to that of the integrated circuit. In order for electronic signals to be transmitted in a device, some other signal needs to amplify and control them. Prior to transistors, vacuum tubes were the only option to provide this amplification. Vacuum tubes were bulky, and they required a lot of power to operate. Before the era of transistors, having a radio in your home meant acquiring a large piece of furniture.

Invention

December 23, 1947 was the day the transistor was first successfully tested. There were three important individuals behind the transistor's development, William Brattain, John Bardeen, and William Shockley. The development of the transistor took place at Bell Labs, the research division of AT&T. Shockley elucidated the scientific theory behind the transistor; in fact, he worked on it for nearly a decade. Brattain and Bardeen came in to actually help Shockley build the physical model, which he had unsuccessfully attempted before. However, the initial design built by the Brattain and Bardeen, called the point-contact transistor, was later usurped by another model designed by Shockley. Shockley's later transistor, the bipolar resistor, was superior and replaced the earlier type. However, the three men were all integral to the development of the transistor, which was recognized when they were jointly awarded the 1956 Nobel Prize for their contributions to physics.

Impact of Transistors

Computers had been around for just under a decade when transistors were invented. The invention of this smaller and more energy efficient means of amplifying electrical signals revolutionized the way computers were designed. A similar impact occurred with radios and television. Texas Instruments (the company which would later spawn the integrated circuit) began the first commercial production of transistors for radios in 1954. Very soon after, Sony acquired the rights to transistor production, producing televisions throughout the next decade that would make the vacuum tube models obsolete.

A perhaps less obvious impact of transistors is the role they played in space travel and satellite technology. To be viable, satellites and space shuttles needed computers that were both small, more durable, and more energy efficient. Transistors provided all these benefits over the initial vacuum tube models.

IBM "The Thinker" Transistor Paperweight (1960's)

The transistor was invented in 1947 by William Shockley, John Bardeen, and Walter Britain of AT&T Bell Telephone Laboratories and quickly replaced the vacuum tube. As a result of the 1956 Consent Decree, AT&T was forced to license the patented transistor technology to any company for $25,000.

The University of Manchester (United Kingdom) built the first experimental computer that used transistors, first operational in 1953. The first commercial fully transistorized computer was the IBM 608, first shipped in 1957.

Because of its fast response and accuracy, the transistor is used in a wide variety of digital and analog amplification, switching, voltage regulation, signal modulation, and oscillators.

Transistors may be packaged individually (known as "discrete transistors") or as part of an integrated circuit, some with over a billion transistors in a very small area.

The two main categories of packaging of discrete transistors are through-hole (or leaded), and surface-mount, also known as surface mount device (SMD).

Transistor packages are made of glass, metal, ceramic or plastic. The package often dictates the power rating and frequency characteristics. Power transistors have large packages that can be clamped to heat sinks for enhanced cooling.