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This paper presents a comparative study on the effect of statistical dopant fluctuations on threshold voltage (<inline-formula> <tex-math notation="LaTeX">$V_{th}$ </tex-math></inline-formula>) of emerging and conventional metal-oxide-semiconductor (MOS) field-effect (FET) transistors (MOSFETs). In this context, three <inline-formula> <tex-math notation="LaTeX">${n}$ </tex-math></inline-formula>-channel MOSFET structures representing three different complementary MOS (CMOS) technologies at the 20 nm node are considered. The structures represent a conventional device with symmetric halo or pocket regions around the <inline-formula> <tex-math notation="LaTeX">$n^{+}$ </tex-math></inline-formula>source-drain formed by a single <inline-formula> <tex-math notation="LaTeX">${p}$ </tex-math></inline-formula>-type dopant implantation; a second conventional device with symmetric <inline-formula> <tex-math notation="LaTeX">${p}$ </tex-math></inline-formula>-type halo regions around the <inline-formula> <tex-math notation="LaTeX">$n^{+}$ </tex-math></inline-formula>source-drain formed by multiple <inline-formula> <tex-math notation="LaTeX">${p}$ </tex-math></inline-formula>-type dopant implantations; and an emerging epitaxial-channel device with symmetric <inline-formula> <tex-math notation="LaTeX">${p}$ </tex-math></inline-formula>-type halo regions around the <inline-formula> <tex-math notation="LaTeX">$n^{+}$ </tex-math></inline-formula>source-drain where the halo regions are formed by up-diffusion of multiple <inline-formula> <tex-math notation="LaTeX">${p}$ </tex-math></inline-formula>-type buried layers from the bulk-substrate during epitaxy. For these devices, the values of <inline-formula> <tex-math notation="LaTeX">$V_{th}$ </tex-math></inline-formula> variance and mismatch are computed as a function of device dimensions. The results show that the multiple-halo devices, in general, offer significantly lower <inline-formula> <tex-math notation="LaTeX">$V_{th}$ </tex-math></inline-formula> variance and mismatch compared to the conventional single-halo devices whereas, the emerging epitaxial-channel multiple-halo MOSFETs offer the lowest <inline-formula> <tex-math notation="LaTeX">$V_{th}$ </tex-math></inline-formula> variability compared to the conventional devices at the same technology node. And, the value of the mismatch coefficient for the emerging technology is about 0.68 mV <inline-formula> <tex-math notation="LaTeX">$\times \mu \text{m}$ </tex-math></inline-formula> compared to that of 1.33 and 1.07 mV <inline-formula> <tex-math notation="LaTeX">$\times \mu \text{m}$ </tex-math></inline-formula> for the conventional single-halo and multiple-halo technologies, respectively. This study, clearly, demonstrates the benefit of the emerging epitaxial-channel buried-halo MOSFETs in significantly reducing the effect of statistical dopant fluctuations on <inline-formula> <tex-math notation="LaTeX">$V_{th}$ </tex-math></inline-formula> at the advanced planar CMOS technology nodes.