Chapter 5 Heterostructure and Compound Semiconductor Devices

Many types of microwave low-noise amplifiers, mixers, and up-converters are cryogenically cooled to achieve the lowest noise possible. The chapter describes the room-temperature devices that present considerable reduced noise at cryogenic temperatures: the GaAs field-effect transistors (GaAs FETs), metal semiconductor field-effect transistor (MESFET), and junction FET (JFET). GaAs FETs should be a better choice for low-power, low-noise …