On the Energy of the Hexagonal Frank Loop in Face Centred Cubic Metals

Recent studies have shown the presence of voids in several face-centered cubic metals after neutron irradiation at elevated temperatures. These voids were found when the irradiation temperature was above 0.3 Tm where Tm is the absolute melting point, and were ascribed to the agglomeration of lattice vacancies resulting from fast neutron generated displacement cascades. The present paper reports the existence of similar voids in the body-centered cubic metals tungsten and molybdenum.

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Defects in ion implanted silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109070 ◽

1978 ◽

Vol 36 (1) ◽

pp. 386-387

Author(s):

J.A. Lambert ◽

P.S. Dobson

Keyword(s):

Defect Structure ◽

Dislocation Loops ◽

Frank Loop ◽

Burgers Vector ◽

Temperature Range ◽

Perfect Dislocation ◽

Contrast Analysis ◽

Image Position ◽

Ion Implanted

The defect structure of ion-implanted silicon, which has been annealed in the temperature range 800°C-1100°C, consists of extrinsic Frank faulted loops and perfect dislocation loops, together with‘rod like’ defects elongated along <110> directions. Various structures have been suggested for the elongated defects and it was argued that an extrinsically faulted Frank loop could undergo partial shear to yield an intrinsically faulted defect having a Burgers vector of 1/6 <411>.This defect has been observed in boron implanted silicon (1015 B+ cm-2 40KeV) and a detailed contrast analysis has confirmed the proposed structure.

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High Resolution Electron Microscopy of internal interfaces in layered materials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100174734 ◽

1990 ◽

Vol 48 (4) ◽

pp. 320-321

Author(s):

Yoichi Ishida ◽

Hideki Ichinose ◽

Yutaka Takahashi ◽

Jin-yeh Wang

Keyword(s):

Grain Boundaries ◽

Mirror Symmetry ◽

Functional Materials ◽

High Resolution Electron Microscopy ◽

Layered Materials ◽

Plane Boundary ◽

Chemical Information ◽

Layer Plane ◽

High Tc ◽

Cubic Metals

Layered materials draw attention in recent years in response to the world-wide drive to discover new functional materials. High-Tc superconducting oxide is one example. Internal interfaces in such layered materials differ significantly from those of cubic metals. They are often parallel to the layer of the neighboring crystals in sintered samples(layer plane boundary), while periodically ordered interfaces with the two neighboring crystals in mirror symmetry to each other are relatively rare. Consequently, the atomistic features of the interface differ significantly from those of cubic metals. In this paper grain boundaries in sintered high-Tc superconducting oxides, joined interfaces between engineering ceramics with metals, and polytype interfaces in vapor-deposited bicrystal are examined to collect atomic information of the interfaces in layered materials. The analysis proved that they are not neccessarily more complicated than that of simple grain boundaries in cubic metals. The interfaces are majorly layer plane type which is parallel to the compound layer. Secondly, chemical information is often available, which helps the interpretation of the interface atomic structure.

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