Influence of the model parameters on the noise performance of double-polysilicon BJTs for microwave LNA's

In the recent past we have measured the noise and the scattering parameters of several series of double polysilicon BJT's over the 2-6 GHz frequency range at different collector current values, according to their emitter finger number. From the experimental data, a noisy circuit model has been extracted based on a T-equivalent network. By means of the correlation matrix techniques, novel analytical expressions of the noise parameters have been derived. As a second step, a sensitivity analysis has been performed for evaluating the influence of each model element on the noise performance. The results show how to improve the characteristics of such devices for a better performance when employed in microwave low-noise amplifiers.