Carrier transport characteristics of small-size field effect transistors

The quantum wave transport of carriers driven by an external electric field (drain bias) is studied numerically in a typical GaAs/AlGaAs heterojunction field effect transistor as a function of the gate bias. We have shown that when the size of the transistor is reduced so that quantum effects become important, the operational characteristics of the transistor are dominated by the conductance quantization effect at infinitely small drain bias and zero temperature. The conductance quantization is diminished when the temperature is increased due to the thermal excitation effect. Normal I-V characteristics of the transistor performance are obtained for small-size field effect transistor where quantum wave transmission is the principal carrier transport mechanism. (C) 1999 Elsevier Science B.V. All rights reserved.