Atomic configurations of dislocation core and twin boundaries in3C−SiCstudied by high-resolution electron microscopy

The geometric phase technique (GPA) for measuring the distortion of crystalline lattices from high-resolution electron microscopy (HRTEM) images will be described. The method is based on the calculation of the “local” Fourier components of the HRTEM image by filtering in Fourier space. The method will be illustrated with a study of an edge dislocation in silicon where displacements have been measured to an accuracy of 3 pm at nanometre resolution as compared with anisotropic elastic theory calculations. The different components of the strain tensor will be mapped out in the vicinity of the dislocation core and compared with theory. The accuracy is of the order of 0.5% for strain and 0.1° for rigid-body rotations. Using bulk elastic constants for silicon, the stress field is determined to 0.5 GPa at nanometre spatial resolution. Accuracy and the spatial resolution of the technique will be discussed.

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High-resolution electron microscopy (HREM) examination of dislocation core structure in B2 FeAl single crystals

Materials Science and Engineering A ◽

10.1016/0921-5093(94)03208-4 ◽

1995 ◽

Vol 192-193 ◽

pp. 83-91 ◽

Cited By ~ 3

Author(s):

D. Sharrott ◽

M.A. Crimp

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Single Crystals ◽

Dislocation Core ◽

High Resolution Electron Microscopy ◽

Core Structure ◽

Resolution Electron ◽

Dislocation Core Structure

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High resolution electron microscopy of ion-irradiated GdBa2Cu3O7

Journal of Materials Research ◽

10.1557/jmr.1991.0677 ◽

1991 ◽

Vol 6 (4) ◽

pp. 677-681 ◽

Cited By ~ 15

Author(s):

G. Van Tendeloo ◽

M-O. Ruault ◽

H. Bernas ◽

M. Gasgnier

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Room Temperature ◽

High Resolution Electron Microscopy ◽

Extended Defects ◽

Twin Boundaries ◽

Resolution Electron

GdBa2Cu3O7 crystals were irradiated at room temperature with 200 keV Ne ions and 300 keV Xe ions. In situ standard TEM and further HREM studies show two types of extended defects: (i) mobile extended defects, which account for the preferential defect pinning to twin boundaries reported earlier. These defects are rapidly recovered and difficult to observe by HREM investigations; (ii) stable amorphous areas which are clearly identified by HREM observations. Their overlapping and aggregation conceivably lead to amorphization of the sample.

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Interaction of twin boundaries with stacking faults in 2H martensite: A high-resolution electron microscopy study

The Philosophical Magazine A Journal of Theoretical Experimental and Applied Physics ◽

10.1080/0141861031000069587 ◽

2003 ◽

Vol 83 (12) ◽

pp. 1479-1493 ◽

Cited By ~ 10

Author(s):

Adriana M. Condó ◽

Francisco C. Lovey ◽

Vicenç Torra

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Stacking Faults ◽

High Resolution Electron Microscopy ◽

Microscopy Study ◽

Electron Microscopy Study ◽

Twin Boundaries ◽

Resolution Electron

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Dislocation core studies using high resolution electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108052 ◽

1978 ◽

Vol 36 (1) ◽

pp. 182-183

Author(s):

D.J.H. Cockayne ◽

G.R. Anstis

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Unique Solution ◽

Lattice Distortion ◽

Image Interpretation ◽

Dislocation Core ◽

High Resolution Electron Microscopy ◽

Resolution Electron ◽

Image Position ◽

Image Detail

The interpretation of high resolution (0.5nm) image detail to study dislocation cores relies upon image calculations for its justification. The scattering equations used to calculate these images make use of various approximations, and their validity at this level of resolution has been in doubt. Because of this, a detailed study has been made of the various methods of image calculation, and the reliability of image interpretation for a number of experimental situations has been determined.Images of dislocations of arbitrary resolution can be calculated by an extension of the approach considered by Howie and Basinski. Given an expansion of the potential V(r) = Σgvg(r) exp (2Πig.r) and wavefunctionsthen, for a given incident wavefunction, the wavefunction ψ(r) = Σgϕg(r) exp (2Πig.r) is the unique solution to the form of Schroedinger's equation in which backscattering is neglected, irrespective of the extent of lattice distortion.

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Structural Studies of Metal-Semiconductor Interfaces with High-Resolution Electron Microscopy

MRS Proceedings ◽

10.1557/proc-14-395 ◽

1982 ◽

Vol 14 ◽

Cited By ~ 23

Author(s):

J. M. Gibson ◽

R. T. Tung ◽

J. M. Poate

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Dislocation Core ◽

High Resolution Electron Microscopy ◽

Nucleation And Growth ◽

Interfacial Structure ◽

Preparation Conditions ◽

Semiconductor Interfaces ◽

Resolution Electron ◽

Crystal Films

ABSTRACTWe have studied interface atomic structure in epitaxial cobalt and nickel disilicides on silicon using high-resolution transmission electron microscopy. By employing UHV techniques during deposition and reaction we have grown truly single-crystalline NiSi2 and CoSi2 films on (111) Si and in the former case on (100) Si. These films are shown to be continuous to below 10Å thickness. By close control over preparation conditions, afforded by UHV, we can greatly influence the nucleation and growth of these films to the extent, for example with NiSi2 on (111)Si, of yielding continuous single-crystal films with either of two orientations as desired. Whilst in the (111) NiSi2 on Si system the interfacial structure invariably appears to well-fit a model in which metal atoms nearest to the interface are 7-fold co-ordinated, for (111) CoSi2 on Si agreement is generally better with a model involving 5-fold co-ordination of these atoms. A misfit dislocation core is also imaged. Results are discussed in the light of silicide nucleation and growth. The structure and stability of the (100) NiSi2 on Si interface is also considered.

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Microstructure of Massively Transformed γ-TiAl Phase Studied by High-Resolution Electron Microscopy

MRS Proceedings ◽

10.1557/proc-460-201 ◽

1996 ◽

Vol 460 ◽

Cited By ~ 2

Author(s):

E. Abe ◽

T. Kumagai ◽

S. Kajiwara ◽

M. Nakamura

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Domain Wall ◽

Domain Boundary ◽

High Resolution Electron Microscopy ◽

Massive Transformation ◽

Mirror Plane ◽

Al Alloy ◽

Twin Boundaries ◽

Resolution Electron

ABSTRACTA microstructure of the massively transformed γ-TiAl (γm) phase in a Ti-48at.%Al alloy, which was heat treated in the high-temperature α-Ti (disordered hep) single phase field (1683K), followed by ice water quenching, has been examined using high-resolution electron microscopy. The characteristic features of the microstructure originated from the α→γ massive transformation have been clarified in detail, which are as follows. (1) Extremely thin hep plates (about 0.8–2nm in thickness), which are considered to be a retained α phase, are found to exist in the γm phase. (2) Twin boundaries are found to be not flat interfaces, that is, twin interfaces are not on the exact (111) mirror plane. This situation is attributed to the existence of a number of partial dislocations at the twin boundaries. (3) Antiphase relationship between the regions either side of the thin rotated domain wall [1] is confirmed. The validity of this situation is explained by assuming that the thin rotated domain wall has been grown from a simple antiphase domain boundary. On the basis of these facts, mechanism of the α→γ massive transformation has been discussed.

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