Statistical Variability in Fully Depleted SOI MOSFETs Due to Random Dopant Fluctuations in the Source and Drain Extensions

Simulations of up to 10 000 fully depleted thin-body silicon-on-insulator MOSFETs show that the standard deviation of the threshold voltage cannot be adequately used as a sole metric of device variability in such transistors. This is due to a sharp departure from normality of the threshold voltage distribution, and an enhanced influence of the source/drain-dopant fluctuations on the on-current and short-channel effects of the fully depleted thin-body silicon-on-insulator transistors. Both aspects have great ramifications for statistical compact models and for low-power SRAM designs.