An improved model for high-frequency noise in BJTs and HBTs interpolating between the quasi-thermal approach and the correlated-shot-noise model

This paper presents and verifies an improved model for high-frequency noise in BJTs and HBTs. Based on measurements on a SiGe:C HBT, a transition from quasithermal behavior at low currents to correlated shot noise at large currents is clearly demonstrated. The model is specially suited for 2D device simulation, since the minimum noise figure can be directly obtained from simulated Y-parameters.