Role of surface step on misfit dislocation nucleation and critical thickness in semiconductor heterostructures

Electron microscopy is well suited for the study of the initial stages of misfit dislocation nucleation and of dislocation reactions. High-resolution Z-contrast imaging has the added advantages of producing intuitively interpretable images with chemical sensitivity. This technique has been used to study film formation and misfit accommodation in epitaxial Ge films grown on Si. The epitaxial Ge films studied herein were produced by steam oxidation of Ge-implanted (001) Si. The implanted Ge is rejected by the growing SiO2 layer and has no time to diffuse into the Si. The partitioned Ge forms a distinct strained epitaxial layer on Si. With this growth process the Ge films are constrained to grow layer-by-layer instead of the normally observed island mode. The growth morphology in turn governs the interfacial misfit dislocation nucleation, location, and character.Figure 1 shows a cross-section view of a dislocation-free 5-nm thick Ge film on (001)Si produced by the oxidation of a Ge (2×l016 ions/cm2) implanted Si wafer. This is three to six times thicker than the observed critical thickness for Ge films grown on Si by more conventional growth processes. Ge normally grows as islands on Si and, after the equivalent of six monolayers of Ge is deposited, dislocations are introduced at the island parameters to relieve the misfit strains.

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Misfit Dislocations in SiGe/Si Heterostructures: Nucleation - Propagation - Multiplication

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.108-109.483 ◽

2005 ◽

Vol 108-109 ◽

pp. 483-488 ◽

Cited By ~ 3

Author(s):

V.I. Vdovin ◽

M.G. Mil'vidskii ◽

M.M. Rzaev ◽

Friedrich Schäffler

Keyword(s):

Experimental Data ◽

Low Temperature ◽

Point Defects ◽

Misfit Dislocation ◽

Alloy Composition ◽

Dislocation Nucleation ◽

Buffer Layers ◽

Misfit Dislocations ◽

Intrinsic Point Defects

We present experimental data on the effect of low-temperature buffer layers on the dislocation structure formation in SiGe/Si strained-layer heterostructures under thermal annealing. Specific subjects include mechanisms of misfit dislocation nucleation, propagation and multiplication as well as the role of intrinsic point defects in these processes. Samples with lowtemperature Si (400°C) and SiGe (250°C) buffer layers were grown by MBE. In general, the processes of MD generation occur similarly in the heterostructures studied independently of the alloy composition (Ge content: 0.15, 0.30) and kind of buffer layer. Intrinsic point defects related to the low-temperature epitaxial growth influence mainly the rate of misfit dislocation nucleation.

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Role of substrate strain to tune energy bands–Seebeck relationship in semiconductor heterostructures

Journal of Applied Physics ◽

10.1063/5.0031523 ◽

2021 ◽

Vol 129 (2) ◽

pp. 025301

Author(s):

Vitaly S. Proshchenko ◽

Manoj Settipalli ◽

Artem K. Pimachev ◽

Sanghamitra Neogi

Keyword(s):

Semiconductor Heterostructures ◽

Energy Bands ◽

Substrate Strain

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Anisotropic misfit dislocation nucleation in two-dimensional grown InAs/GaAs(001) heterostructures

Applied Physics Letters ◽

10.1063/1.122088 ◽

1998 ◽

Vol 73 (8) ◽

pp. 1074-1076 ◽

Cited By ~ 15

Author(s):

Achim Trampert ◽

Klaus H. Ploog ◽

Eric Tournié

Keyword(s):

Misfit Dislocation ◽

Dislocation Nucleation ◽

Two Dimensional

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Critical Thickness for Misfit Dislocation Formation in InAs/GaAs(110) Heteroepitaxy

Progress in Industrial Mathematics at ECMI 2006 - Mathematics in Industry ◽

10.1007/978-3-540-71992-2_57 ◽

2008 ◽

pp. 381-386

Author(s):

I. Plans ◽

A. Carpio ◽

L. L. Bonilla ◽

R. E. Caflisch

Keyword(s):

Misfit Dislocation ◽

Critical Thickness ◽

Dislocation Formation

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Electron Transport Through Epitaxial Metal/Semiconductor Heterostructures

MRS Proceedings ◽

10.1557/proc-77-271 ◽

1986 ◽

Vol 77 ◽

Cited By ~ 4

Author(s):

A. F. J. Levi ◽

R. T. Tung ◽

J. L. Batstone ◽

J. M. Gibson ◽

M. Anzlowar ◽

...

Keyword(s):

Electron Transport ◽

Schottky Barrier ◽

Semiconductor Heterostructures ◽

Perfect Single Crystal ◽

Barrier Heights ◽

Semiconductor Interfaces ◽

Semiconductor Contacts ◽

First Time ◽

Silicon Heterostructures

ABSTRACTAbrupt, epitaxial silicide/silicon heterostructures may be grown so that, for the first time, the physics of electron transport across near perfect, single crystal, metal/semiconductor interfaces may be probed experimentally. Transport measurements through type-A and -B oriented NiSi2 layers on Si(111) substrates have revealed Schottky barrier heights differing by 140 meV. In this paper we present results of experiments designed to explore the possible role of bulk and interface defects in determining the potential barrier at these near ideal epitaxial metal-semiconductor contacts. We have found little evidence for the presence of defects and the Schottky barrier is insensitive to details of the microscopic interfacial perfection. By contrast we find that both the electrical quality and magnitude of the barrier occurring at the NiSi2 /Si(100) heterojunction are dependent upon details of the microscopic interfacial perfection.

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