Conference Paper

Single dopant impact on electrical characteristics of SOI NMOSFETs with effective length down to 10nm

DOI: 10.1109/VLSIT.2010.5556224 Conference: VLSI Technology (VLSIT), 2010 Symposium on
Source: IEEE Xplore


Although single dopant signatures have been observed at low temperature [1-2], the impact on transistor performance of a single dopant atom at room temperature is not yet well understood. Here, for the first time, we provide an in-depth understanding of single dopant influence on NMOSFETs characteristics by linking low and room temperature transport. We demonstrate that, for gate length of 30 nm and below (channel length down to 10 nm), the presence of a single dopant dramatically alters the subthreshold behaviour when the dopant is located in the middle of the channel. Moving the dopants away from the channel leads to enhanced variability above the threshold voltage Vt.

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