Drift-field transistor
The drift-field transistor, also called the drift transistor or graded base transistor, is a type of high-speed bipolar junction transistor having a doping-engineered electric field in the base to reduce the charge carrier base transit time.
Invented by Herbert Kroemer at the Central Bureau of Telecommunications Technology of the German Postal Service, in 1953, it continues to influence the design of modern high-speed bipolar junction transistors.