William Shockley
The first bipolar junction transistors were invented by Bell Labs' William Shockley, which applied for patent (2,569,347) on June 26, 1948. On April 12, 1950, Bell Labs chemists Gordon Teal and Morgan Sparks had successfully produced a working bipolar NPN junction amplifying germanium transistor. Bell Labs had announced the discovery of this new "sandwich" transistor in a press release on July 4, 1951.