The Invention of the Transistor: Bell Labs, 1947
1947 · event
Just before Christmas 1947, in a laboratory in New Jersey, two physicists pressed a small triangle of plastic wrapped in gold foil against a piece of germanium and watched a weak electrical signal come out stronger than it went in. John Bardeen and Walter Brattain had built the first working transistor. On 23 December they demonstrated it to their managers at Bell Telephone Laboratories, and the device was announced publicly the following summer.
The problem they had been set was practical. Telephone networks relied on vacuum tubes to amplify signals, and tubes were fragile, hot, power hungry and slow to switch on. A solid piece of semiconductor that could do the same work would be smaller, cooler and far more reliable. William Shockley, who led the group, went on to design the junction transistor in 1948, a form that could actually be manufactured in quantity, and the three shared the Nobel Prize in Physics in 1956.
The first products were modest, hearing aids and then portable radios, which is how the word transistor entered ordinary speech. What followed was not modest at all. Once several transistors could be built on a single piece of silicon, the integrated circuit followed, and the number of them that fit on a chip has been doubling at a steady rate for decades.
Every computer, telephone, car, satellite and medical scanner in use today runs on the descendants of that device. More transistors are now manufactured each year than any other object in human history, by an enormous margin, and they are individually smaller than most viruses. The demonstration of December 1947 is the point where the electronic age begins.