1st successful test of the transistor, December 16, 1947
In 1945, AT&T’s research division, Bell Labs, began working on technology to replace vacuum tubes and make long-distance telephone service more reliable. William Shockley organized a solid-state physics group to research semiconductor replacements for vacuum tubes and electromechanical switches.
Possibly influenced by JE Lilienfled’s idea for the field-effect transistor patented in 1926, Shockley conceived of a “field-effect” amplifier and switch based on recent germanium and silicon technology. He built a small cylinder coated thinly with silicon, mounted close to a small, metal plate, but was unable to get it to work.
A member of the research team, John Bardeen, suggested electrons on the semiconductor surface could be blocking the penetration of electric fields in Shockley’s experiments. Bardeen and Walter Brattain began using a silicon contraption built to help study how electrons acted on the surface of a semiconductor to test the theory.
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