Comparison of High-frequency Noise Correlation Models in SiGe HBTs

Considering the noise correlation term between collector and base current shot noise, there mainly are four noise parameter models of SiGe HBTs, including the unified noise model (UNI), two SPICE noise models (SPN1, SPN2), the thermodynamic noise model (TDN). A comparison of these models was investigated in this work. A SiGe HBT based on BiCMOS process was fabricated and its S-parameters and Minimum Noise Figure were tested. Through the comparison between the measurement and the simulation results from these models, two of the models, the UNI and the SPN2, were obviously in good agreement with the measured results at high-frequency.