Identification of Growth Induced Planar Defects in Silicon

1985 ◽  
Vol 62 ◽  
Author(s):  
H. P. Strunk ◽  
A. Kessler ◽  
E. Bauser
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Crystal Growth ◽  
Epitaxial Layers ◽  
Growth Interface ◽  
Fringe Contrast ◽  
Planar Defects ◽  
Transmission Electron ◽  
Contrast Analysis ◽  
Preferential Incorporation

ABSTRACTPlanar defects have been detected by transmission electron microscopy in silicon epitaxial layers that have been grown from Ga solutions below 500 °C. According to fringe contrast analysis, this defect can be modelled by a plane of Ga atoms within the Si lattice. This plane forms during crystal growth due to local preferential incorporation of Ga atoms at crystallographically defined sites, that occur repetitively in the trains of monomolecular growth steps at the liquid/solid growth interface.

Characterization of GaN grown on sapphire by laser-induced molecular beam epitaxy

2001 ◽  
Vol 16 (1) ◽  
pp. 261-267 ◽  
Author(s):  
H. Zhou ◽  
A. Rühm ◽  
N. Y. Jin-Phillipp ◽  
F. Phillipp ◽  
M. Gross ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
X Ray Diffraction ◽  
Fringe Contrast ◽  
Inversion Domain ◽  
Transmission Electron ◽  
Contrast Analysis ◽  
Inversion Domain Boundaries

GaN grown on sapphire (α–Al2O3) was characterized by laser-induced molecular beam epitaxy. Threading dislocations with Burgers vectors of 1/3〈1120〉, 1/3〈1123〉 and [0001] were observed with a predominance of the first type. Additionally, inversion domains with Ga-polarity existed with respect to the adjacent matrix, which was of N-polarity. The dislocation densities and coherence lengths were deduced from x-ray diffraction and found to be in accordance with those measured by transmission electron microscopy. Both displacement fringe contrast analysis and high-resolution transmission electron microscopy results indicated that the inversion domain boundaries had Ga–N bonds between domains and the adjacent matrix.

Black-white contrast of dislocation loops

1978 ◽  
Vol 36 (1) ◽  
pp. 328-329
Author(s):  
J. J. Hren ◽  
W. D. Cooper ◽  
L. J. Sykes
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Dislocation Loops ◽  
Major Premise ◽  
Burgers Vector ◽  
Transmission Electron ◽  
Primary Means ◽  
Contrast Analysis ◽  
Dot Product ◽  
Imaging Conditions

Small dislocation loops observed by transmission electron microscopy exhibit a characteristic black-white strain contrast when observed under dynamical imaging conditions. In many cases, the topography and orientation of the image may be used to determine the nature of the loop crystallography. Two distinct but somewhat overlapping procedures have been developed for the contrast analysis and identification of small dislocation loops. One group of investigators has emphasized the use of the topography of the image as the principle tool for analysis. The major premise of this method is that the characteristic details of the image topography are dependent only on the magnitude of the dot product between the loop Burgers vector and the diffracting vector. This technique is commonly referred to as the (g•b) analysis. A second group of investigators has emphasized the use of the orientation of the direction of black-white contrast as the primary means of analysis.

Influence of doping on crystal growth, structure and optical properties of nanocrystalline CaTiO3: a case study using small-angle neutron scattering

2015 ◽  
Vol 48 (3) ◽  
pp. 836-843 ◽  
Author(s):  
Oindrila Mondal ◽  
Manisha Pal ◽  
Ripandeep Singh ◽  
Debasis Sen ◽  
Subhasish Mazumder ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Optical Properties ◽  
Crystal Growth ◽  
Small Angle Neutron Scattering ◽  
Ionic Radius ◽  
Ionic Radii ◽  
Growth Structure ◽  
Transmission Electron ◽  
The Difference

The effect of dopant size (ionic radius) on the crystal growth, structure and optical properties of nanocrystalline calcium titanate, CaTiO3(CTO), have been studied using small-angle neutron scattering. X-ray diffraction, along with high-resolution transmission electron microscopy, confirms the growth of pure nanocrystalline CTO. Rietveld analysis reveals that the difference of ionic radii between dopant and host ions induces strain within the lattice, which significantly affects the lattice parameters. The induced strain, due to the difference of ionic radii, causes the shrinkage of the optical band gap, which is manifested by the redshift of the absorbance band. Mesoscopic structural analysis using scattering techniques demonstrates that the ionic radius of the dopant influences the agglomeration behaviour and particle size. A high-resolution transmission electron microscopy study reconfirms the formation of pure highly crystalline CTO nanoparticles.

A Study Of Domain Boundary Structures In Lead Titanate Single Crystals

1991 ◽  
Vol 238 ◽  
Author(s):  
C. C. Chou ◽  
J. Li ◽  
C. M. Wayman
Keyword(s):  
Electron Microscopy ◽  
Single Crystals ◽  
Lead Titanate ◽  
Mixed Type ◽  
Domain Boundary ◽  
Dynamical Theory ◽  
Fringe Contrast ◽  
Transmission Electron ◽  
Domain Boundaries ◽  
Contrast Analysis

ABSTRACTDomain boundary structures of flux-grown poly-domain lead titanate single crystals have been studied using transmission electron microscopy. 90° and 180° domain boundaries were seen in the crystals and were systematically analyzed under various diffraction conditions. Although 90° domain boundaries are supposely δ-type boundaries in BaTiO3, our results show that displacement plays an important role at boundaries and the extreme fringe contrast (EFC) behavior of 90° boundaries is of the mixed type. In the present work, an analysis based upon the two beam dynamical theory was conducted and a rule similar to stacking-fault contrast analysis was established to predict the geometric configuration of a 180° domain boundary using EFC behavior. Examples are given and verified by tilting experiments and electron diffraction. The results are consistent and offer a convenient way to distinguish between 90° and 180° boundaries.

scholarly journals Probing planar defects in nanoparticle superlattices by 3D small-angle electron diffraction tomography and real space imaging

Nanoscale ◽  
2014 ◽  
Vol 6 (22) ◽  
pp. 13803-13808 ◽  
Author(s):  
Arnaud Mayence ◽  
Dong Wang ◽  
German Salazar-Alvarez ◽  
Peter Oleynikov ◽  
Lennart Bergström
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Electron Diffraction ◽  
Real Space ◽  
Diffraction Tomography ◽  
Planar Defects ◽  
Pd Nanoparticle ◽  
Transmission Electron ◽  
Nanoparticle Superlattices ◽  
Microscopy Techniques

Planar defects in Pd nanoparticle superlattices were revealed by a combination of real and reciprocal space transmission electron microscopy techniques. 3D electron diffraction tomography was extended to characterize mesoscale imperfections.

Crystal Growth Rates in Doped SbxTe Fast-Growth Phase-Change Films Studied with Transmission Electron Microscopy

2008 ◽  
Vol 1072 ◽  
Author(s):  
Bart J. Kooi ◽  
Ramanathaswamy Pandian ◽  
Jeff Th. M. De Hosson
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Crystal Growth ◽  
Phase Change ◽  
Growth Phase ◽  
Growth Rates ◽  
Fast Growth ◽  
Various Boundary Conditions ◽  
Dielectric Layers ◽  
Transmission Electron

ABSTRACTIsothermal crystallization of doped SbxTe fast-growth phase-change films was investigated using transmission electron microscopy with in situ heating. SbxTe films with four different values for the Sb/Te ratio, x=3.0, 3.3, 3.6 and 4.2, were analyzed and the films were sandwiched between two types of dielectric layers. One dielectric layer type is based on 80at.%ZnS-20at.%SiO2, the other on (Ge,Cr)N. The crystal growth rates reduce if the phase-change films are sandwiched between amorphous dielectric layers. The reduction is very pronounced at the lowest measured temperatures (150 °C), becomes smaller at higher temperatures and probably disappears at around 200 °C. The crystal growth rates increase with increasing Sb/Te ratio, but the activation energy for crystal growth is not significantly affected by the Sb/Te ratio. Finally a systematic study of the effect of the electron beam of the TEM on the crystal growth rates is performed showing accelerated growth rates. The present work shows that particularly at relative low temperatures, just above the glass-transition temperature, the growth rates as limited by the atomic mobilities are sensitive to various (boundary) conditions, e.g. capping layers and irradiation.

Energy-Minimizing Structures For Low-Angle Grain Boundaries in Zinc

1985 ◽  
Vol 43 ◽  
pp. 258-261
Author(s):  
Fu-Rong Che ◽  
A.H. King
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Grain Boundaries ◽  
State Of The Art ◽  
Pure Zinc ◽  
Planar Defects ◽  
Cubic Metals ◽  
Transmission Electron ◽  
Dislocation Models ◽  
Solute Interaction

Dislocation models for low angle grain boundaries have been widely known since 1950 and the proposed structures have been extensively confirmed by transmission electron microscopy, although most studies have been confined to the cubic metals. A generalization of the earlier geometrical work, known as the 0-lattice, represents the state of the art in predicting grain boundary structures on a purely geometrical basis, but the analysis is always predicated on the assumption that grain boundaries are basically planar defects. In some work on precipitation in the Al-Zn-Mg system Vanderwalker and Vander Sande observed non-planar low angle grain boundaries, although these may have been the results of pinning by embryonic precipitates or other solute interaction effects: we have observed non-planar boundaries in pure zinc where no such pinning effects are available to explain the puckering.

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