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Title: Low-temperature growth morphology of singular and vicinal Ge(001)

Abstract

Scanning tunneling microscopy is used to study the nonequilibrium surface morphology of singular and vicinal Ge(001) grown by molecular-beam epitaxy. Growth on substrates with {approx}0.1{degree} miscut produces patterns of nearly symmetrical growth mounds over a wide range of growth temperature, 60{lt}T{lt}230{degree}C and film thickness, 0.5{lt}h{lt}1000nm. The characteristic slope or aspect ratio of the growth mounds increases with film thickness. Analysis of the onset of mound formation gives an estimate of the Ehrlich-Schwoebel length; l{sub ES} is approximately equal to the surface lattice constant and independent of temperature. This small value for l{sub ES} implies either a weak repulsive barrier ({Delta}E{sub d}{approximately}k{sub B}T) at descending steps or a step-adatom attraction ({Delta}E{sub a}{gt}k{sub B}T) at ascending steps. Buffer layers grown at T=365{degree}C on vicinal substrates (9{degree} miscut towards [110]) show (115) facets. Low-temperature growth on vicinal surfaces (6{degree} and 9{degree} miscuts at T=155 and 230{degree}C) produces highly anisotropic growth ridges oriented along the miscut direction with larger roughness amplitude and smaller in-plane length scales than mounds produced by the same growth conditions on singular substrates. At 230{degree}C, the slopes of the growth ridges are stabilized by the (105) surface. {copyright} {ital 1998} {ital The American Physical Society}

Authors:
; ;  [1]
  1. Department of Materials Science and Engineering, and Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801 (United States)
Publication Date:
OSTI Identifier:
614991
Resource Type:
Journal Article
Journal Name:
Physical Review, B: Condensed Matter
Additional Journal Information:
Journal Volume: 57; Journal Issue: 19; Other Information: PBD: May 1998
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; GERMANIUM; STRUCTURAL CHEMICAL ANALYSIS; MOLECULAR BEAM EPITAXY; CRYSTAL GROWTH; LATTICE PARAMETERS; CRYSTALS; SURFACES; MORPHOLOGY; TEMPERATURE DEPENDENCE

Citation Formats

Van Nostrand, J E, Chey, S J, and Cahill, D G. Low-temperature growth morphology of singular and vicinal Ge(001). United States: N. p., 1998. Web. doi:10.1103/PhysRevB.57.12536.
Van Nostrand, J E, Chey, S J, & Cahill, D G. Low-temperature growth morphology of singular and vicinal Ge(001). United States. doi:10.1103/PhysRevB.57.12536.
Van Nostrand, J E, Chey, S J, and Cahill, D G. Fri . "Low-temperature growth morphology of singular and vicinal Ge(001)". United States. doi:10.1103/PhysRevB.57.12536.
@article{osti_614991,
title = {Low-temperature growth morphology of singular and vicinal Ge(001)},
author = {Van Nostrand, J E and Chey, S J and Cahill, D G},
abstractNote = {Scanning tunneling microscopy is used to study the nonequilibrium surface morphology of singular and vicinal Ge(001) grown by molecular-beam epitaxy. Growth on substrates with {approx}0.1{degree} miscut produces patterns of nearly symmetrical growth mounds over a wide range of growth temperature, 60{lt}T{lt}230{degree}C and film thickness, 0.5{lt}h{lt}1000nm. The characteristic slope or aspect ratio of the growth mounds increases with film thickness. Analysis of the onset of mound formation gives an estimate of the Ehrlich-Schwoebel length; l{sub ES} is approximately equal to the surface lattice constant and independent of temperature. This small value for l{sub ES} implies either a weak repulsive barrier ({Delta}E{sub d}{approximately}k{sub B}T) at descending steps or a step-adatom attraction ({Delta}E{sub a}{gt}k{sub B}T) at ascending steps. Buffer layers grown at T=365{degree}C on vicinal substrates (9{degree} miscut towards [110]) show (115) facets. Low-temperature growth on vicinal surfaces (6{degree} and 9{degree} miscuts at T=155 and 230{degree}C) produces highly anisotropic growth ridges oriented along the miscut direction with larger roughness amplitude and smaller in-plane length scales than mounds produced by the same growth conditions on singular substrates. At 230{degree}C, the slopes of the growth ridges are stabilized by the (105) surface. {copyright} {ital 1998} {ital The American Physical Society}},
doi = {10.1103/PhysRevB.57.12536},
journal = {Physical Review, B: Condensed Matter},
number = 19,
volume = 57,
place = {United States},
year = {1998},
month = {5}
}