EXPERIMENTAL-VERIFICATION AND NUMERICAL APPLICATION OF THE THERMODYNAMIC APPROACH TO HIGH-FREQUENCY NOISE IN SIGE HBTS

We present experimental and numerical results on high-frequency noise of Silicon-Germanium heterojunction bipolar transistors (SiGe HBTs) ba sed on small-signal analysis. The minimum noise figure for an SiGe HBT is determined from s-parameter measurements. The approach is verified through comparison with a conventionally measured noise figure and ca n be used to extract the noise figure from device simulation. By using a two-dimensional device simulation code, we calculate the high-frequ ency noise figure from the simulated y-parameters. The simulation resu lts are in good agreement with the measured minimum noise figure. We u se the model to predict the effect of lateral downscaling on the minim um noise figure. (C) 1997 Elsevier Science Ltd.