Static Analysis of Random Telegraph Noise in a 45-nm Channel Length Conventional MOSFET Device: Threshold Voltage and ON-Current Fluctuations

摘要

In this paper, we investigate the threshold voltage and ON-current fluctuations due to the presence of charged traps located in the middle portion of the channel when the trap is moved from the source end to the drain end of the channel in a 45-nm technology node device with an effective channel length of 35 nm. Our thorough investigations suggest that the threshold voltage fluctuation and its standard deviation are much larger than the ON-current fluctuation since in the ON-state screening effectively reduces the strength of the trap Coulomb potential, which is not the case in the OFF-state. We believe that this is a first study that simultaneously investigates the effects of random dopant and random telegraph noise fluctuations that utilizes particle-based device simulators that correctly account for the long-range and the short-range Coulomb interaction. Unique feature of the approach is the proper incorporation, in a self-consistent manner, of the short-range Coulomb interaction via the real-space molecular dynamics routine. Indeed, Vasileska has pioneered this technique back in 1996. We also find that studies that do not account for the short-range Coulomb interaction correctly miss important feature that the threshold voltage standard deviations are not independent upon the position of the trap in the channel but are strongly correlated with it when the trap is located in the middle section of the source end of the channel. This suggests that an approach that correctly accounts for the short-range Coulomb interaction is a must when modeling either random dopant or random trap fluctuations in both the threshold voltage and the ON-current.