Narrow-Width Effect on High-Frequency Performance and RF Noise of Sub-40-nm Multifinger nMOSFETs and pMOSFETs

The impact of narrow-width effects on high-frequency performance like fT, f_MAX, and RF noise parameters, such as NF_min and Rn, in sub-40-nm multifinger CMOS devices is investigated in this paper. Narrow-oxide-diffusion (OD) MOSFET with smaller finger width and larger finger number can achieve lower Rg and higher f_MAX. However, these narrow-OD devices suffer fT degradation and higher NF_min, even with the advantage of lower Rg. The mechanisms responsible for the tradeoff between different parameters will be presented to provide an important guideline of multifinger MOSFET layout for RF circuit design using nanoscale CMOS technology.