Effect of Source/Drain Doping Gradient on Threshold Voltage Variation in Double-Gate Fin Field Effect Transistors as Determined by Discrete Random Doping

概要

論文の詳細を見る
We present a numerical simulation and physical analysis of how a single dopant in the channel region effects the variation of threshold voltage $\Delta V_{\text{th}}$ in highly scaled (gate length = 16 nm) and undoped double-gate fin field effect transistors. The presence of a single contaminant dopant in an undoped channel with an abrupt source/drain (S/D) doping gradient can cause a severe change in $\Delta V_{\text{th}}$ (140 mV owing to a single acceptor; 100 mV owing to a single donor). To effectively suppress this severe variation, we suggest S/D doping gradient engineering to make the lateral straggle of S/D doping ($\sigma_{\text{S/D}}$) larger than 2 nm to minimize $\Delta V_{\text{th}}$. The distribution of $V_{\text{th}}$ is also estimated by three-dimensional simulation using the position of the dopant.
2010-10-25