skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Self-Organized Si Dots On Ge Substrates

Abstract

The epitaxial growth conditions for silicon on germanium substrates were investigated as a function of growth temperature and monolayer coverage. Island formation was observed for the hole studied temperature range, although strong alloying with the substrate occurred for the highest temperatures. Carbon pre-deposition offers suitable nucleation centers for the Si island and reduction of alloying. pre-structured Ge substrates were prepared to enhance islanding and to achieve ordering.

Authors:
; ;  [1]
  1. Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz, Altenbergerstr. 69, A-4040 Linz (Austria)
Publication Date:
OSTI Identifier:
21055069
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 893; Journal Issue: 1; Conference: ICPS 2006: 28. international conference on the physics of semiconductors, Vienna (Austria), 24-28 Jul 2006; Other Information: DOI: 10.1063/1.2729783; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CARBON; DEPOSITION; EPITAXY; GERMANIUM; NUCLEATION; QUANTUM DOTS; SEMICONDUCTOR MATERIALS; SILICON; SUBSTRATES; TEMPERATURE DEPENDENCE

Citation Formats

Pachinger, D., Lichtenberger, H., and Schaeffler, F. Self-Organized Si Dots On Ge Substrates. United States: N. p., 2007. Web. doi:10.1063/1.2729783.
Pachinger, D., Lichtenberger, H., & Schaeffler, F. Self-Organized Si Dots On Ge Substrates. United States. doi:10.1063/1.2729783.
Pachinger, D., Lichtenberger, H., and Schaeffler, F. Tue . "Self-Organized Si Dots On Ge Substrates". United States. doi:10.1063/1.2729783.
@article{osti_21055069,
title = {Self-Organized Si Dots On Ge Substrates},
author = {Pachinger, D. and Lichtenberger, H. and Schaeffler, F.},
abstractNote = {The epitaxial growth conditions for silicon on germanium substrates were investigated as a function of growth temperature and monolayer coverage. Island formation was observed for the hole studied temperature range, although strong alloying with the substrate occurred for the highest temperatures. Carbon pre-deposition offers suitable nucleation centers for the Si island and reduction of alloying. pre-structured Ge substrates were prepared to enhance islanding and to achieve ordering.},
doi = {10.1063/1.2729783},
journal = {AIP Conference Proceedings},
number = 1,
volume = 893,
place = {United States},
year = {Tue Apr 10 00:00:00 EDT 2007},
month = {Tue Apr 10 00:00:00 EDT 2007}
}
  • In Ge heteroepitaxy on vicinal Si(001), miscut by 4.8 deg. toward [100], pyramid-shaped faceted quantum dot islands ('huts') form continuously from individual (105) facets on a wetting layer of coexisting (105) and (001) segments. Via this barrierless kinetic route the first three-dimensional islands rapidly form wherever there are substantial local gradients along <100> in-plane directions.
  • In{sub x}Ga{sub 1-x}As self-organized quantum dots with x=1.0, 0.5, and 0.35 have been grown by molecular beam epitaxy. The areal density, distribution, and shapes have been found to be dependent on x. The dot shape changes from a round shape for x=1.0 to an elliptical shape for x{<=}0.5. The major axis and minor axis of the elliptical In{sub x}Ga{sub 1-x}As dots are along the [1(bar sign)10] and [110] directions, respectively. The ordering phenomenon is also discussed. It is suggested that the dot-dot interaction may play important roles in the self-organization process. (c) 2000 American Institute of Physics.
  • Self-organized anisotropic strain engineering guided on shallow- and deep-patterned GaAs (311)B substrates is exploited for formation of complex laterally ordered architectures of connected InGaAs quantum dot (QD) arrays and isolated InAs QD groups by molecular beam epitaxy. The combination of strain and step engineerings on shallow stripe-patterned substrates transforms the periodic spotlike arrangement of the InGaAs QD arrays and InAs QD groups (on planar substrates) into a zigzag arrangement of periodic stripes which are well ordered over macroscopic areas on zigzag mesa-patterned substrates. In contrast, the formation of slow-growing facets on deep-patterned substrates produces QD-free mesa sidewalls, while InGaAs QDmore » arrays and InAs QD groups form on the GaAs (311)B top and bottom planes with arrangements modified only close to the sidewalls depending on the sidewall orientation. The QDs on the shallow- and deep-patterned substrates exhibit excellent optical properties up to room temperature. Therefore, the concept of guided self-organization demonstrated on shallow-patterned (due to steps) and deep-patterned (due to facets) substrates is highlighted for creation of complex architectures of laterally ordered QDs for future quantum functional devices.« less
  • We have utilized resonant Raman scattering to investigate the phonon modes of self-organized Ge quantum dots grown by molecular-beam epitaxy. Both Ge-Ge and Si-Ge phonon modes are found to exhibit strong enhancements at the E{sub 1} exciton. The strain in the quantum dots deduced from the phonon energies is consistent with the results of high-resolution transmission electron microscopy. An upper bound on the confinement energy of the E{sub 1} exciton in quantum dots was deduced. The enhancement strength in the Si-Ge phonon indicates strong interaction between this mode and the E{sub 1} exciton of the Ge dots. {copyright} {ital 1999}more » {ital The American Physical Society}« less
  • Microsized Ge wires can appear spontaneously when grown on a vicinal Si (111) surface miscut by 4 along the [11-2] direction by using molecular-beam epitaxy. Time-resolved in situ grazing incidence small-angle scattering of x rays, atomic force microscopy, and micro-Raman scattering show that the formation of Ge microwires is due to coalescence of islands along the step edges and ripening of the structures accompanied by a partial consumption of the wetting layer.