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Title: Deterministic control of plasma-assembled self-organized Ge/Si quantum dot arrays

Abstract

Self-assembly of size-uniform and spatially ordered quantum dot (QD) arrays is one of the major challenges in the development of the new generation of semiconducting nanoelectronic and photonic devices. Assembly of Ge QD (in the {approx}5-20 nm size range) arrays from randomly generated position and size-nonuniform nanodot patterns on plasma-exposed Si(100) surfaces is studied using hybrid multiscale numerical simulations. It is shown, by properly manipulating the incoming ion/neutral flux from the plasma and the surface temperature, the uniformity of the nanodot size within the array can be improved by 34%-53%, with the best improvement achieved at low surface temperatures and high external incoming fluxes, which are intrinsic to plasma-aided processes. Using a plasma-based process also leads to an improvement ({approx}22% at 700 K surface temperature and 0.1 ML/s incoming flux from the plasma) of the spatial order of a randomly sampled nanodot ensemble, which self-organizes to position the dots equidistantly to their neighbors within the array. Remarkable improvements in QD ordering and size uniformity can be achieved at high growth rates (a few nm/s) and a surface temperature as low as 600 K, which broadens the range of suitable substrates to temperature-sensitive ultrathin nanofilms and polymers. The results of thismore » study are generic, can also be applied to nonplasma-based techniques, and as such contributes to the development of deterministic strategies of nanoassembly of self-ordered arrays of size-uniform QDs, in the size range where nanodot ordering cannot be achieved by presently available pattern delineation techniques.« less

Authors:
; ;  [1]
  1. Plasma Nanoscience at Complex Systems, School of Physics, The University of Sydney, Sydney NSW 2006 (Australia)
Publication Date:
OSTI Identifier:
20982849
Resource Type:
Journal Article
Journal Name:
Journal of Applied Physics
Additional Journal Information:
Journal Volume: 101; Journal Issue: 9; Other Information: DOI: 10.1063/1.2727448; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-8979
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; COMPUTERIZED SIMULATION; CRYSTAL GROWTH; GERMANIUM; PLASMA; POLYMERS; QUANTUM DOTS; SEMICONDUCTOR MATERIALS; SILICON; SUBSTRATES

Citation Formats

Ho, J C, Levchenko, I, and Ostrikov, K. Deterministic control of plasma-assembled self-organized Ge/Si quantum dot arrays. United States: N. p., 2007. Web. doi:10.1063/1.2727448.
Ho, J C, Levchenko, I, & Ostrikov, K. Deterministic control of plasma-assembled self-organized Ge/Si quantum dot arrays. United States. doi:10.1063/1.2727448.
Ho, J C, Levchenko, I, and Ostrikov, K. Tue . "Deterministic control of plasma-assembled self-organized Ge/Si quantum dot arrays". United States. doi:10.1063/1.2727448.
@article{osti_20982849,
title = {Deterministic control of plasma-assembled self-organized Ge/Si quantum dot arrays},
author = {Ho, J C and Levchenko, I and Ostrikov, K},
abstractNote = {Self-assembly of size-uniform and spatially ordered quantum dot (QD) arrays is one of the major challenges in the development of the new generation of semiconducting nanoelectronic and photonic devices. Assembly of Ge QD (in the {approx}5-20 nm size range) arrays from randomly generated position and size-nonuniform nanodot patterns on plasma-exposed Si(100) surfaces is studied using hybrid multiscale numerical simulations. It is shown, by properly manipulating the incoming ion/neutral flux from the plasma and the surface temperature, the uniformity of the nanodot size within the array can be improved by 34%-53%, with the best improvement achieved at low surface temperatures and high external incoming fluxes, which are intrinsic to plasma-aided processes. Using a plasma-based process also leads to an improvement ({approx}22% at 700 K surface temperature and 0.1 ML/s incoming flux from the plasma) of the spatial order of a randomly sampled nanodot ensemble, which self-organizes to position the dots equidistantly to their neighbors within the array. Remarkable improvements in QD ordering and size uniformity can be achieved at high growth rates (a few nm/s) and a surface temperature as low as 600 K, which broadens the range of suitable substrates to temperature-sensitive ultrathin nanofilms and polymers. The results of this study are generic, can also be applied to nonplasma-based techniques, and as such contributes to the development of deterministic strategies of nanoassembly of self-ordered arrays of size-uniform QDs, in the size range where nanodot ordering cannot be achieved by presently available pattern delineation techniques.},
doi = {10.1063/1.2727448},
journal = {Journal of Applied Physics},
issn = {0021-8979},
number = 9,
volume = 101,
place = {United States},
year = {2007},
month = {5}
}