An accurate modeling of noise temperature for AlGaAs/GaAs HEMTs and Al
GaAs/InGaAs/GaAs Pseudomorphic HEMTs (PHEMTs) is presented. The analys
is is based on a self-consistent solution of Schrodinger and Poisson's
equations. Pseudomorphic HEMTs have a lower noise temperature as comp
ared to normal AlGaAs/GaAs HEMTs. The minimum noise temperature in pse
udomorphic HEMTs decreases with increasing quantum-well (QW) width. No
ise temperature in general increases with increasing gate length.