Microwave noise modeling for AlGaAs/InGaAs/GaAs PHEMTs

Analytical. expressions for the noise Parameters of microwave pseudomorphic high electron mobility transistors (PHEMT) are presented in this article. These expressions are derived from an accurate small-signal and noise equivalent circuit model, which takes into account the influences of the intrinsic elements and gate leakage current. The scaling rules for the noise parameters of the intrinsic part are determined based on these analytical expressions. The experimental and theoretical results show that at the same bias condition, good scaling of the noise parameters up to 26 GHz can be achieved between the large-size devices (2 x 40 mu m and 260 gm gate width PHEMTs) and the elementary cell (2 x 20 mu m gate width PHEMT).