A Study on the Strain and Microstructure in SiGe Film Grown on Si(001) Substrate by MBE

1994 ◽  
Vol 356 ◽  
Author(s):  
Kyoung-Ik Cho ◽  
Sahn Nahm ◽  
Sang-Gi Kim ◽  
Seung-Chang Lee ◽  
Kyung-Soo Kim ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Molecular Beam ◽  
Large Strain ◽  
Strain Relaxation ◽  
Stacking Faults ◽  
Double Crystal ◽  
Crystalline Layer ◽  
X Ray ◽  
Transmission Electron ◽  
Plain Strain

AbstractSi/Si0.8Ge0.2/Si(001) structures were grown at various growth temperatures (250 ∼ 760 °C) using molecular beam epitaxy, and the variation of strain and microstructure of the film was investigated using double crystal X-ray diffractometry and transmission electron microscopy. SiGe films with good single crystallinity were obtained at the growth temperatures of 440 ∼ 600 °C. For the samples grown below 350 °C, an amorphous SiGe film was developed over the SiGe single crystalline layer with a jagged amorphous/crystalline (a/c) interface, and many defects such as stacking faults and microtwins were formed below the a/c interface. Dislocations were developed through out the films for the samples grown above 680 °C. In addition, for the samples grown below 680 °C, the amount of in-plane strain of the SiGe film was found to be about − 8×l0−3 without strain relaxation. However, the SiGe films grown at 760 °C have small in-plain strain of − 4×l0−3 and large strain relaxation of 50%.

Vertical-Cavity Optoelectronic Structures: CAD, Growth, and Structural Characterization

1992 ◽  
Vol 281 ◽  
Author(s):  
D. H. Christensen ◽  
S. M. Crochiere ◽  
J. G. Pellegrino ◽  
R. S. Rai ◽  
C. A. Parsons ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Computer Aided Design ◽  
Molecular Beam ◽  
Alloy Composition ◽  
Double Crystal ◽  
X Ray ◽  
Transmission Electron ◽  
Random Alloys ◽  
Aided Design ◽  
Vertical Cavity

ABSTRACTSimulations of reflectance spectra and electric field distributions for vertical-cavity structures were used in the computer aided design of epitaxial mirrors and lasers. The binary GaAs/AlAs superlattice alloys and AlxGa1−xAs random alloys that compose these structures were grown by molecular beam epitaxy. Photoluminescence, photoreflectance, reflectance spectroscopy, scanning electron microscopy, transmission electron microscopy, and double crystal x-ray diffractometry were applied to characterize cavity and Bragg mirror layer thicknesses and alloy composition.

Tem Study of Temperature Influence on The Crystalline Quality of InGaAs/Si Epilayers

1992 ◽  
Vol 263 ◽  
Author(s):  
A. Vila ◽  
A. Cornet ◽  
J.R. Morante ◽  
D.I. Westwood
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Molecular Beam ◽  
Temperature Influence ◽  
X Ray Diffraction ◽  
Double Crystal ◽  
X Ray ◽  
Transmission Electron ◽  
Different Temperatures

ABSTRACTA Transmission Electron Microscopy (TEM) study of In0.53Ga0.47As Molecular Beam Epitaxy films grown at different temperatures onto misoriented Si (100) substrates is presented. The evolution of the density of the different kind of defects is discussed as a function of the growth temperature in the range between 200 and 500° C. The results are compared with the characterization techniques of Double Crystal X-Ray Diffraction and Hall effect.

Stacking Faults in SiC Nanowires

2008 ◽  
Vol 8 (7) ◽  
pp. 3504-3510 ◽  
Author(s):  
K. L. Wallis ◽  
M. Wieligor ◽  
T. W. Zerda ◽  
S. Stelmakh ◽  
S. Gierlotka ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Stacking Faults ◽  
Multiwall Carbon Nanotubes ◽  
Structural Defects ◽  
X Ray Diffraction ◽  
Ir Spectrometry ◽  
X Ray ◽  
Sic Nanowires ◽  
Transmission Electron ◽  
Multiwall Carbon

SiC nanowires were obtained by a reaction between vapor silicon and multiwall carbon nanotubes, CNT, in vacuum at 1200 °C. Raman and IR spectrometry, X-ray diffraction and high resolution transmission electron microscopy, HRTEM, were used to characterize properties of SiC nanowires. Morphology and chemical composition of the nanowires was similar for all samples, but concentration of structural defects varied and depended on the origin of CNT. Stacking faults were characterized by HRTEM and Raman spectroscopy, and both techniques provided complementary results. Raman microscopy allowed studying structural defects inside individual nanowires. A thin layer of amorphous silicon carbide was detected on the surface of nanowires.

Tem Study of the Structure of Mbe GaAs Layers Grown at Low Temperature

1990 ◽  
Vol 198 ◽  
Author(s):  
Zuzanna Liliental-Weber
Keyword(s):  
Electron Microscopy ◽  
Low Temperature ◽  
Molecular Beam ◽  
Critical Thickness ◽  
Stacking Faults ◽  
Structural Quality ◽  
Crystalline Perfection ◽  
Transmission Electron ◽  
Low Temperature Gaas

ABSTRACTThe structural quality of GaAs layers grown at 200°C by molecular beam epitaxy (MBE) was investigated by transmission electron microscopy (TEM). We found that a high crystalline perfection can be achieved in the layers grown at this low temperature for thickness up to 3 μm. In some samples we observed pyramid-shaped defects with polycrystalline cores surrounded by microtwins, stacking faults and dislocations. The size of these cores increased as the growth temperature was decreased and as the layer thickness was increased. The upper surface of layers with pyramidal defects became polycrystalline at a critical thickness of the order of 3μm. We suggested that the low-temperature GaAs becomes polycrystalline at a critical thickness either because of a decrease in substrate temperature during growth or because strain induced by excess As incorporated in these layers leads to the formation of misoriented GaAs nuclei, thereby initiating polycrystalline growth. The pyramidal shape of the defects results from a growth-rate hierarchy of the low index planes in GaAs.

Double Periodicity Formation in EuTe/PbTe Superlattices

1995 ◽  
Vol 399 ◽  
Author(s):  
M. Shima ◽  
L. Salamanca-Riba ◽  
G. Springholz ◽  
G. Bauer
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Short Period ◽  
Short Period Superlattices

ABSTRACTMolecular beam epitaxy was used to grow EuTe(x)/PbTe(y) short period superlattices with x=1-4 EuTe(111) monolayers alternating with y≈3x PbTe monolayers. The superlattices were characterized by transmission electron microscopy and high resolution x-ray diffraction. Regions with double periodicity were observed coexisting with areas of nominal periodicity. The sample with x=3.5 and y=9, for example, contains regions with double periodicity of x=7 and y=17. X-ray diffraction measurements confirm the formation of the double periodicity in these samples by the appearance of weak satellites in between the satellites of the nominal periodicity. The double periodicity in the superlattice is believed to result from interdiffusion during the growth. A model for this process is presented.

scholarly journals Structural Property Study for GeSn Thin Films

Materials ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 3645
Author(s):  
Liyao Zhang ◽  
Yuxin Song ◽  
Nils von den Driesch ◽  
Zhenpu Zhang ◽  
Dan Buca ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Molecular Beam ◽  
Chemical Vapor ◽  
Threading Dislocations ◽  
X Ray Diffraction ◽  
Cross Sectional ◽  
X Ray ◽  
Transmission Electron

The structural properties of GeSn thin films with different Sn concentrations and thicknesses grown on Ge (001) by molecular beam epitaxy (MBE) and on Ge-buffered Si (001) wafers by chemical vapor deposition (CVD) were analyzed through high resolution X-ray diffraction and cross-sectional transmission electron microscopy. Two-dimensional reciprocal space maps around the asymmetric (224) reflection were collected by X-ray diffraction for both the whole structures and the GeSn epilayers. The broadenings of the features of the GeSn epilayers with different relaxations in the ω direction, along the ω-2θ direction and parallel to the surface were investigated. The dislocations were identified by transmission electron microscopy. Threading dislocations were found in MBE grown GeSn layers, but not in the CVD grown ones. The point defects and dislocations were two possible reasons for the poor optical properties in the GeSn alloys grown by MBE.

Analysis and Reduction of Stacking Faults in Fast Epitaxial Growth

2016 ◽  
Vol 858 ◽  
pp. 173-176 ◽  
Author(s):  
Hideyuki Uehigashi ◽  
Keisuke Fukada ◽  
Masahiko Ito ◽  
Isaho Kamata ◽  
Hiroaki Fujibayashi ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Growth Rate ◽  
Epitaxial Growth ◽  
Stacking Faults ◽  
High Growth ◽  
High Growth Rate ◽  
X Ray ◽  
Crystalline Defects ◽  
Transmission Electron

We have developed a single-wafer vertical epitaxial reactor which realizes high-throughput production of 4H-SiC epitaxial layer (epilayer) with a high growth rate [1,2]. In this paper, in order to evaluate the crystalline defects which can affect the characteristics of devices, we investigated the formation of variety of in-grown stacking faults (SFs) in detail. Synchrotron X-ray topography, photoluminescence (PL) and transmission electron microscopy are employed to analyze the SFs and the origins of the SF formation are discussed. The result in reducing in-grown SFs in fast epitaxial growth is also shown.

High-density stacking faults in a supersaturated nitrided layer on austenitic stainless steel

2016 ◽  
Vol 49 (6) ◽  
pp. 1967-1971 ◽  
Author(s):  
Ke Tong ◽  
Fei Ye ◽  
Honglong Che ◽  
Ming Kai Lei ◽  
Shu Miao ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Stainless Steel ◽  
Austenitic Stainless Steel ◽  
Nitrided Layer ◽  
Stacking Faults ◽  
High Density ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

The nitrogen-supersaturated phase produced by low-temperature plasma-assisted nitriding of austenitic stainless steel usually contains a high density of stacking faults. However, the stacking fault density observed in previous studies was considerably lower than that determined by fitting the X-ray diffraction pattern. In this work, it has been confirmed by high-resolution transmission electron microscopy that the strip-shaped regions of about 3–25 nm in width observed at relatively low magnification essentially consist of a series of stacking faults on every second {111} atomic plane. A microstructure model of the clustered stacking faults embedded in a face-centred cubic structure was built for these regions. The simulated X-ray diffraction and transmission electron microscopy results based on this model are consistent with the observations.

Microstructure of Carbon Encapsulated Superparamagnetic Co Nanoparticles

2001 ◽  
Vol 704 ◽  
Author(s):  
Xiang-Cheng Sun ◽  
J. Reyes-Gasga ◽  
X. L. Dong
Keyword(s):  
Electron Microscopy ◽  
Arc Discharge ◽  
Stacking Faults ◽  
Good Evidence ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Lattice Images ◽  
Co Nanoparticles ◽  
Discharge Method

AbstractCarbon encapsulated magnetic Co nanoparticles have been synthesized by modified arc-discharge method. Both high-resolution transmission electron microscopy (HREM) and powder x-ray diffraction (XRD) profiles reveal the presence of 8-15nm diameter crystallites coated with 1-3 carbon layers. Specially, HREM images indicate that the intimate and contiguous carbon fringe around those Co nanoparticles is good evidence for complete encapsulation by carbon shell layers. The encapsulated phases are identified as hcp (α)-Co, fcc (β)-Co and cobalt carbide (Co3C) nanocrystals by using x-ray diffraction, electron diffraction and energy dispersive x-ray analysis. However, some fcc (β)-Co particles with a significant fraction of stacking faults are observed by HREM and confirmed by means of numerical Fourier transform (FFT) of HREM lattice images. In particular, the carbon encapsulation formation and growth mechanism are also reviewed.

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