Abstract
Remote charge scattering (RCS) has become a serious obstacle inhabiting the performance of ultrathin gate oxide MOSFETs. In this paper, we evaluate the impact of RCS by treating the real-space full Coulomb interaction between remote charges and inversion carriers. A new approach that can be simply incorporated in ensemble Monte Carlo (EMC) based simulations without any variation of the standard EMC simulator is developed. The charge-carrier (c-c) interaction model is based on a particle-mesh (PM) calculation method which resolves both the long-range and short-range Coulomb interactions by solving Poisson’s equation on a refined mesh. The validity of our approach is verified by three-dimensional (3-D) resistor simulations, from which the obtained doping dependence of the low-field mobility agrees well with experimental results. The proposed approach is then used to study the impact of RCS on the drive current and carrier transport properties in the channel of a 20 nm silicon (Si) nMOS FinFET with HfO2 gate stack. We find that the influence of RCS is strongly localized in the vicinity of the remote charges and exhibits a granular nature, indicating the necessity to consider the full Coulomb interaction in RCS.
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Wei, K., Egley, J., Liu, X. et al. Remote charge scattering: a full Coulomb interaction approach and its impact on silicon nMOS FinFETs with HfO2 gate dielectric. Sci. China Inf. Sci. 57, 1–9 (2014). https://doi.org/10.1007/s11432-013-4810-0
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DOI: https://doi.org/10.1007/s11432-013-4810-0