title: Atomistic study on dopant-distributions in realistically sized, highly P-doped Si nanowires.
abstract: The dependency of dopant-distributions on channel diameters in realistically sized, highly phosphorus-doped silicon nanowires is investigated with an atomistic tight-binding approach coupled to self-consistent Schrödinger-Poisson simulations. By overcoming the limit in channel sizes and doping densities of previous studies, this work examines electronic structures and electrostatics of free-standing circular silicon nanowires that are phosphorus-doped with a high density of ∼ 2 × 10(19) cm(-3) and have 12 nm-28 nm cross-sections. Results of analysis on the channel energy indicate that the uniformly distributed dopant profile would be hardly obtained when the nanowire cross-section is smaller than 20 nm. Insufficient room to screen donor ions and shallower impurity bands are the primary reasons of the nonuniform dopant-distributions in smaller nanowires. Being firmly connected to the recent experimental study (Proc. Natl. Acad. Sci. U.S.A. 2009, 106, 15254-15258), this work establishes the first theoretical framework for understanding dopant-distributions in over-10 nm highly doped silicon nanowires.
authors.affiliation: National Institute of Supercomputing and Networking, Korea Institute of Science and Technology Information , Daejeon 305-806, Republic of Korea.
authors.forename: Hoon
authors.initials: H
authors.lastname: Ryu
authors.forename: Jongseob
authors.initials: J
authors.lastname: Kim
authors.forename: Ki-Ha
authors.initials: KH
authors.lastname: Hong
keywords: Highly doped nanostructures; P-doped Si nanowires; Schrödinger−Poisson simulations; atomistic modeling; dopant-distributions