The Transistor: The Tiny Switch Humanity Has Built 13 Sextillion Times

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The transistor is the most manufactured artifact in human history: by 2018, more than 13 sextillion had been made. It replaced the thermionic triode, a glass vacuum tube invented in 1907 that had to boil electrons off a heated plate, ran hot, and burned out like a light bulb. Physicist Julius Edgar Lilienfeld patented a solid-state alternative in Canada in 1925, but the pure semiconductor crystals needed to build it did not exist. The breakthrough came at Bell Labs in December 1947.

This episode explains how the device was invented, how it became microscopic, and how a speck of silicon does arithmetic. John Bardeen and Walter Brattain succeeded after William Shockley's first design failed, and the three shared the 1956 Nobel Prize in Physics. A furnace accident in 1955 then opened the way to printing transistors by the million. The story ends with the weaknesses of solid-state electronics and the places where vacuum tubes still win.

• Shockley's field-effect attempt was blocked by electrons trapped at the crystal surface, so Bardeen and Brattain pressed two gold point contacts directly onto germanium.
• Bell Labs engineer John R. Pierce coined the name by combining transfer and resistor. In France, Herbert Mataré and Heinrich Welker independently built a similar device in 1948 and called it the transistron.
• Carl Frosch and Lincoln Derick accidentally grew a silicon dioxide layer on a wafer in 1955, which led to photolithography and to the MOSFET, invented by Mohamed Atalla and Dawon Kahng in 1959.
• The MOSFET accounts for roughly 99.9 percent of all transistors, and a single Apple M3 Max chip holds about 92 billion.
• A cosmic ray can flip a transistor from zero to one, a single event upset, which is one reason tubes survive in broadcast transmitters, satellites, and guitar amplifiers.