Phase Noise Upconversion of non-1/ f Device Noise in Gate-All-Around Technology Nodes

Phase noise is a key metric for evaluating oscillator stability in RF circuits, typically exhibiting a close-in spectral slope of 1/f3 due to the upconversion of underlying 1/f device noise. However, in advanced technology nodes, such as FinFETs, deviations from this expected behavior are increasingly observed, often driven by effects like random telegraph noise. In this work, we analyze how a novel form of non-1/f noise present in Gate-All-Around transistors affects oscillator phase noise, with a focus on its statistical behavior as a function of device size based on measurements across multiple devices and bias conditions. Our findings highlight the limitations of traditional noise assumptions and demonstrate the need for design strategies that account for the specific characteristics of non-1/f noise sources. We also show that accurate phase noise predictions require refined noise models that capture both bias and area dependence, as well as statistical variability across devices.