Three-dimensional simulation of discrete oxide charge effects in 0.1 mu m MOSFETs

The threshold voltage fluctuation caused by random distribution of discrete oxide charges is studied using three-dimensional (3D) simulations. It is f ound that the effect of discrete oxide charges on the terminal current vari ation depends on their lateral positions in the channel and, for the same n umber fluctuations of discrete charges, a large threshold voltage fluctuati on is introduced in a device with deeper source/drain junction depth (X-j). The effect of 3D current flow is found to give negligible effect on the th reshold voltage fluctuation. Finally, the effects of oxide charges and dopa nts on the threshold voltage fluctuation are compared. (C) 2001 Elsevier Sc ience Ltd. All rights reserved.