Variability and sensitivity to process parameters variations in InGaAs dual-gate ultra-thin body MOSFETs: A scaling perspective

In this work, we present a combined analysis on the statistical variability of threshold voltage, on-state current, and leakage current of III-V ultra-scaled MOSFETs. In addition, we analyze the sensitivity of threshold voltage to critical geometrical and process parameters variations (i.e., gate length, channel thickness, oxide thickness and channel doping). Our analysis verifies the scaling potential of the InGaAs technology from the variability/sensitivity standpoint for two technological nodes (L
_g
= 15 nm, L
_g
= 10.4 nm), by means of Quantum Drift-Diffusion (QDD) simulations. The structure under investigation is a template Dual-Gate Ultra-Thin Body device realized following ITRS projections. The variability sources under consideration are: Random Dopant Fluctuation (RDF), Work Function Fluctuation (WFF), Body- and Gate-Line Edge Roughness (LER). The sensitivity analysis of threshold voltage is performed by considering also the effects of statistical variability to evaluate their combined effect. The results of the statistical variability analysis highlight the importance of carefully controlling Body-LER, as forecasted in the new IRDS report. Moreover, the combined effect of variability and sensitivity to channel thickness are found to be critical to the scaling process (down to L
_g
=10.4 nm), as it leads to significant leakage increase or performance reduction, potentially resulting in always-on devices.