TCAD simulation of interface traps related variability in bulk decananometer mosfets

Interface traps can introduce random variations in the drain current of MOSFETs, becoming a source of device variability. In this work, 2D and 3D TCAD simulations of devices with channel length in the decananometer range are carried out to analyze the impact of their spatial distribution on the drift of the threshold voltage. 2D simulations show that traps located close to the center of the channel lead to larger threshold voltage shifts. Moreover, as the non-uniformity increases, larger threshold voltages and variability are observed. 3D simulations indicate that this trend is only observed in large area devices, pointing out that the study of the variability of small area devices must be carried out through 3D simulations.