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Invention of the Point Contact Transistor, 1954

The P-N Junction and its Function

Semiconductors with too many electrons are classified as N-type, while semiconductors with too few electrons are classified as P-type. The boundary between these two types of semiconductors is known as a P-N junction, and when the P-N junction is present current can begin to flow from one side to the other.

Knowledge of the P-N Junction enabled Bardeen and Brattain to build their Point Contact Transistor. The thumbnails at right lead to notes accompanying the Committee on Science and the Arts report on both men and their invention and state the opinion that Bardeen and Brattain are responsible for the invention and deserving of a Ballantine Medal.