Defects in ion implanted silicon

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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Black-white contrast of dislocation loops

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108787 ◽

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.

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Changes in the Burgers Vector of Perfect Dislocation Loops without Contact with the External Dislocations

Physical Review Letters ◽

10.1103/physrevlett.96.125506 ◽

2006 ◽

Vol 96 (12) ◽

Cited By ~ 89

Author(s):

K. Arakawa ◽

M. Hatanaka ◽

E. Kuramoto ◽

K. Ono ◽

H. Mori

Keyword(s):

Dislocation Loops ◽

Burgers Vector ◽

Perfect Dislocation

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Change in the Burgers Vector of Perfect Dislocation Loops in Iron

Materia Japan ◽

10.2320/materia.44.984 ◽

2005 ◽

Vol 44 (12) ◽

pp. 984-984

Author(s):

Kazuto Arakawa ◽

Makoto Hatanaka ◽

Eiichi Kuramoto ◽

Kotaro Ono ◽

Hirotaro Mori

Keyword(s):

Dislocation Loops ◽

Burgers Vector ◽

Perfect Dislocation

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Detection of the Spontaneous Change in the Burgers Vector of Perfect Dislocation Loops in Iron

Microscopy and Microanalysis ◽

10.1017/s1431927605503568 ◽

2005 ◽

Vol 11 (S02) ◽

Cited By ~ 1

Author(s):

K Arakawa ◽

M Hatanaka ◽

H Mori

Keyword(s):

Dislocation Loops ◽

Burgers Vector ◽

Spontaneous Change ◽

Perfect Dislocation

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Point defect generation during the oxidation of silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010010874x ◽

1978 ◽

Vol 36 (1) ◽

pp. 320-321

Author(s):

J.A. Lambert ◽

P.S. Dobson

Keyword(s):

Thin Foil ◽

Geometrical Factor ◽

Dislocation Loops ◽

Self Diffusion ◽

Self Energy ◽

Thin Foils ◽

Perfect Dislocation ◽

Interstitial Defects ◽

Boron Ions ◽

Image Position

The interstitial defects created during ion-implantation in silicon condense out during annealing to form extrinsically faulted Frank loops and perfect dislocation loops. The annealing behaviour of these defects has been investigated by annealing electron microscope thin foils. It was found that the loops shrink and eventually disappear after annealing in the temperature range 900-1020° C in vacuum. Figure 1a shows faulted and perfect loops after implanting with 10 15 boron ions cm-2 at 40kV and bulk annealing for 50 minutes in nitrogen at 950° C. The thin foil was then annealed for 30 minutes at 1000° C in vacuum and figure 1b shows that the loops have shrunk during this treatment.The loop shrinkage is caused by the diffusion of interstitial point defects from the loop to the surface and the driving force for this process is provided by the self energy of the loops. The rate of shrinkage is given bywhere A is a geometrical factor, Ds is the coefficient of self diffusion and ΔF is the change in the free energy of the loop per emitted interstitial.

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The formation and growth of vacancy loops in magnesium

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1968.0175 ◽

1968 ◽

Vol 307 (1488) ◽

pp. 71-81 ◽

Cited By ~ 22

Keyword(s):

Surface Oxidation ◽

Stacking Fault ◽

Stacking Fault Energy ◽

Dislocation Loops ◽

Temperature Range ◽

Vacancy Loops ◽

A Value ◽

Thin Foils ◽

Contrast Analysis ◽

Kinetics Of

Single, double and multi-layered dislocation loops have been observed in thin foils of quenched magnesium, and the structure of the loops established by contrast analysis. On annealing in the temperature range 150 to 200°C the loops are observed to grow as a result of the production of vacancies by surface oxidation of magnesium. The kinetics of loop growth have been analysed and a value of 125 ± 25 erg/cm 2 for the stacking fault energy obtained.The reliability and significance of the value in governing the properties of magnesium is discussed.

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Dislocation Arrangement in a Thick LEO GaN Film on Sapphire

MRS Internet Journal of Nitride Semiconductor Research ◽

10.1557/s1092578300004130 ◽

2000 ◽

Vol 5 (S1) ◽

pp. 97-103

Author(s):

Kathleen A. Dunn ◽

Susan E. Babcock ◽

Donald S. Stone ◽

Richard J. Matyi ◽

Ling Zhang ◽

...

Keyword(s):

High Resolution ◽

Electron Diffraction ◽

Threading Dislocations ◽

X Ray Diffraction ◽

Burgers Vector ◽

X Ray ◽

The Third ◽

Dislocation Arrangement ◽

Image Position ◽

Gan Film

Diffraction-contrast TEM, focused probe electron diffraction, and high-resolution X-ray diffraction were used to characterize the dislocation arrangements in a 16µm thick coalesced GaN film grown by MOVPE LEO. As is commonly observed, the threading dislocations that are duplicated from the template above the window bend toward (0001). At the coalescence plane they bend back to lie along [0001] and thread to the surface. In addition, three other sets of dislocations were observed. The first set consists of a wall of parallel dislocations lying in the coalescence plane and nearly parallel to the substrate, with Burgers vector (b) in the (0001) plane. The second set is comprised of rectangular loops with b = 1/3 [110] (perpendicular to the coalescence boundary) which originate in the coalescence boundary and extend laterally into the film on the (100). The third set of dislocations threads laterally through the film along the [100] bar axis with 1/3<110>-type Burgers vectors These sets result in a dislocation density of ∼109 cm−2. High resolution X-ray reciprocal space maps indicate wing tilt of ∼0.5º.

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