Impact of impedance-dependent receiver gain on the extracted channel thermal noise in sub-100 nm MOSFETs

To continue the pursuit of Moore’s law, process variations become a very crucial aspect in fabrications, characterization, and modeling for devices with feature size in the sub-100 nm region. To characterize these process variations, measurements are conducted over hundreds or thousands of transistors, and the experimental uncertainties due to the instruments are assumed to be smaller than that of the device itself, and therefore often be overlooked. This assumption might be true for I–V, C–V, or scattering parameter measurements, but this is not the case for high-frequency noise characterization. This paper presents, for the first time, evidence that the instrument can easily contribute 10–17% uncertainties in the measured power spectral densities (PSDs) of the channel thermal noise in 90 nm MOSFETs.