Impact of Junction Nonabruptness on Random-Discrete-Dopant Induced Variability in Intrinsic Channel Trigate Metal-Oxide-Semiconductor Field-Effect Transistors

摘要

Using full three-dimensional (3D) technology computer-aided design (TCAD) simulations, we present a comprehensive statistical study on the random discrete dopant (RDD) induced variability in state-of-the-art intrinsic channel trigate MOSFETs. This paper is focused on the RDD variability sources that are introduced by dopant diffusion from highly doped source/drain (S/D) regions into the undoped channel region, which is referred to as junction nonabruptness (JNA). By considering a realistic lateral doping profile in the channel and evaluating the impact of JNA on the variability of performance parameters such as threshold voltage (V_(th)), subthreshold slope (SS), drain-induced barrier lowering (DIBL), on current (/I_(on)), and off current (I_(OFF))), we show that the effect of JNA can lead to substantial device variations. The nonnegligible influence of JNA puts limitations on device scaling, which is also investigated in this paper.