| With BiCMOS technology, both BJT and MOS devices are available in building RF transceivers. To utilize these two devices in the front-end of systems, their noise characteristics have to be fully characterized and modeled. Once the received signals are down converted to the base band frequency range, CMOS devices are used in the digital signal processing. The fast switching digital signals can drive CMOS devices into non-quasi-static (NQS) state, resulting in a time delay in the output responses. To accurately model the digital system response, the NQS effect has to be included in the MOS model.;The thesis covers the noise analysis of both BJT and MOS devices, as well as the NQS modeling of MOS transistors. A compact model for BJT noise analysis is developed taking into consideration the transmission line effect due to the lateral intrinsic base resistance combined with the capacitance along the emitter width. An empirical model is also formulated to give a design guideline on how to scale the spacer thickness, which determines the extrinsic base resistance, with the emitter width. Characterizations are done on MOS devices to investigate the impact of hot carriers on the noise performance. Furthermore, a robust NQS model is developed and implemented in a compact MOS model, with a view to precisely evaluating the timing behavior of the system. |
