Heterostructure Field Effect Transistor, Physical Analysis and New Structures

Physical phenomena that occur in conventional AlGaAs-GaAs MODFETs are briefly described. This covers quantum effects, carrier transport properties, influence of electric field... Progress in device modeling allow to obtain valuable information on device behaviour as well as various intervening physical effects and to predict the performance. Limitations resulting from both technological imperfections and specific device operations, e.g. low temperature, large power are investigated. New structures such as inverted MODFET, SISFET, and pseudomorphic MODFETs are described and their potential capabilities are discussed.