Nanosized metal grains induced electrical characteristic fluctuation in 16-nm-gate high-κ/metal gate bulk FinFET devices

In this work, the work function fluctuation (WKF) induced variability in 16-nm-gate bulk N-FinFET is for the first time explored by an experimentally calibrated 3D device simulation. Random nanosized grains of TiN gate are statistically positioned in the gate region to examine the associated carriers' transport, concurrently capturing "grain number variation" and "grain position fluctuation." The newly developed localized WKF simulation method enables us to estimate the threshold voltage fluctuation of devices with respect to the aspect ratio (AR = fin height/fin width) which accounts for the random grain's size, number and position effects simultaneously.