Correlation between interface traps and random dopants in emerging MOSFETs

Abstract

In this work, we for the first time study the fluctuation and interaction between interface traps (ITs) and random dopants (RDs) of 16 nm MOSFETs. Totally random devices with 2D ITs at Si/high-к oxide interface and 3D RDs inside channel are simultaneously examined using an experimentally validated 3D device simulation. Pure random ITs at Si/high-к oxide interface will increase the threshold voltage (Vth) due to enlarge potential barrier resulting from accept-like ITs. However, the fluctuation of Vth (σVth) induced by ITs is smaller than the result of RDs. Considering the effect of ITs and RDs at the same time will result in coupled localized spikes of potential barrier and induced characteristics are much more correlated to each other which can not be estimated using adiabatic statistical sum calculation. Consequently, the effect of random ITs and RDs on device variability should be counted simultaneously for high-к / metal gate devices.