Reduction of Random Dopant Fluctuation-induced Variation in Junctionless FinFETs via Negative Capacitance Effect

Bo Liu, Xianlong Chen, Ziqiang Xie, Mengxue Guo, Mengjie Zhao, Weifeng Lyu


In this study, we investigated the impact of random dopant fluctuation (RDF) on junctionless (JL) fin field-effect transistors (FinFETs) with ferroelectric (FE) negative capacitance (NC) effect. The RDF-induced variations were captured by using built-in Sano methodology in three-dimensional technology computer-aided design (TCAD) simulation. Compared to the regular JL-FinFETs, the variations in JL-FinFETs with NC effect (NCJL-FinFETs) was observed to be less via statistical Monte Carlo analysis, which further enhanced its performance as well. The evaluation and estimation of threshold voltage (VT), ON-state current (Ion), OFF-state current (Ioff), and subthreshold swing (SS) by different FE layer thicknesses indicated reduction in the standard deviations of VT (δVT) and Ion (δIon) by 34.7% and 7.08%, respectively; the OFF-state current and its standard deviation shrank by approximately three orders of magnitude than the JL-FinFET counterpart. Although δSS was not monotonous, the SS was significantly improved to sub-60 mV/decade. To sum up, the regular JL-FinFETs containing the FE layer as NC effect not only improved the electrical performance, but also led to the resilience of the RDF-induced statistical variability.


Random dopant fluctuations (RDF); negative capacitance effect; junctionless FinFETs; Monte Carlo analysis

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