Lecture 9 Heterojunction Bipolar Transistor (HBT) -1948 Bell Labs Bardeen and Brattain Ge point-contact transistor -1949 Bell Labs Shockley’s classic paper on junction diode and transistors 1951 Bell Labs the first junction bipolar transistor

See Sze&Ng pp.243-254 From x=0 to x=W, the injected minority-carriers Distribution (electrons) is governed by the Continuity equation:

In normal mode, VBC<0 and np(W)=0 Base transport factor aT=InC/InE For W<<Ln, InC ~=InE

Common-base Current gain Emitter injection efficiency Common-emitter Current gain

SiGe HBT Technology

GaAs HBT Technology

InP HBT Technology

The world's fastest transisitor has a frequency of 509 gigahertz. CHAMPAIGN, Ill. — Researchers at the University of Illinois at Urbana-Champaign have broken their own record for the world’s fastest transistor.

Homework: Read and study “Physics of Semiconductor Devices” Chapter 5 Bipolar Transistors “High-speed semiconductor devices” Chapter 6 Bipolar Transistors (2) Due on February 7, 2019 Thursday