Title :
Computational exploration of novel silicon nanostructures
Author :
Nishio, Kengo ; Ozaki, Taisuke ; Morishita, Tetsuya ; Shinoda, Wataru ; Mikami, Masuhiro
Author_Institution :
Res. Inst. for Comput. Sci. (RICS), Nat. Inst. of Adv. Ind. Sci. & Technol. (AIST), Tsukuba
Abstract :
Discovery of novel Si nanostructures would open up a new avenue for science and technology as the discoveries of C60 and carbon nanotubes did. With this expectation, we have explored novel Si nanostructures by combining empirical molecular dynamics simulations and structure optimizations with the density functional theory. Our molecular-dynamics simulations demonstrate (1) an icosahedral Si nanodot forms by freezing a droplet in vacuum, (2) Si-fullerene-linked nanowires, such as Si16- and Si20-linked nanowires, form by freezing liquid Si inside carbon nanotubes, and (3) a polyicosahedral Si nanowire forms by freezing liquid Si inside a cylindrical nanopore. The unique cage structure of the polyicosahedral Si nanowire allows us to tune the electronic properties by encapsulating guest atoms into its cages. Our density functional theory calculations reveal that a semiconducting hydrogen-terminated polyicosahedral Si nanowire becomes metallic by the sodium and iodine doping.
Keywords :
band structure; density functional theory; elemental semiconductors; iodine; molecular dynamics method; nanowires; semiconductor quantum wires; silicon; sodium; Si-fullerene-linked nanowires; Si:I; Si:Na; cage structure; density functional theory; electronic properties; empirical molecular-dynamics simulations; freezing; icosahedral nanodot; iodine doping; semiconducting hydrogen-terminated polyicosahedral nanowire; silicon nanostructures; sodium doping; structure optimizations; Atomic measurements; Carbon nanotubes; Crystallization; Density functional theory; Equations; Nanoscale devices; Nanostructures; Nanowires; Potential energy; Silicon;
Conference_Titel :
Ultimate Integration of Silicon, 2009. ULIS 2009. 10th International Conference on
Conference_Location :
Aachen
Print_ISBN :
978-1-4244-3704-7
DOI :
10.1109/ULIS.2009.4897539