The Effect of a Thin Sample on the Extended Defect Evolution in Si+ Implanted Si

1997 ◽  
Vol 490 ◽  
Author(s):  
Jing-Hong Li ◽  
Kevin S. Jones
Keyword(s):  
Dislocation Loop ◽  
Ex Situ ◽  
Dissolution Process ◽  
Dislocation Loops ◽  
Loop Formation ◽  
Thin Sample ◽  
Extended Defect ◽  
Defect Evolution ◽  
Annealing Study

ABSTRACTThe annealing kinetics of implant damage in Si+ implanted Si has been investigated using in-situ and ex-situ annealing of transmission electron microscopy (TEM) samples prepared prior to annealing. The defect evolution at 800°C was studied for a Si wafer implanted with Si+ at 100keV to a dose of 2×1014 cm-2. This implant was above the sub-threshold loop formation threshold allowing one to study simultaneously the {311} defect dissolution and dislocation loop nucleation and growth. In order to study the effect on the defect evolution of using a thin sample for an in-situ annealing experiment, a pair of samples, one thick and one thinned into a TEM sample, were annealed in a furnace simultaneously. It was found that the presence of a second surface 2000Å below the implant damage did not affect the extended defect evolution. For the in-situ annealing study it was found that the {311} dissolution process and sub-threshold dislocation loop formation process was not affected by the TEM electron beam at 160kV as long as an 800°C furnace pre-anneal was done prior to in-situ annealing. The dissolution rate of the {311} defects was used to confirm the TEM holder furnace temperature. The results of both the in-situ the {311} defects is released during the 311 dissolution process and 30% comes to reside in dislocation loops. Thus, the loops appear to contain a significant fraction of the total interstitial concentration introduced by the implant.

In situ TEM and multiscale study of dislocation loop formation in the vicinity of a grain boundary

2020 ◽  
Vol 528 ◽  
pp. 151872 ◽  
Author(s):  
Qingshan Dong ◽  
Peyman Saidi ◽  
Laurent K. Béland ◽  
Zhongwen Yao ◽  
Cong Dai ◽  
...  
Keyword(s):  
Grain Boundary ◽  
Dislocation Loop ◽  
In Situ Tem ◽  
Loop Formation

Fundamental Modeling of Transient Enhanced Diffusion through Extended Defect Evolution

1997 ◽  
Vol 469 ◽  
Author(s):  
A. H. Gencer ◽  
S. Chakravarthi ◽  
I. Clejan ◽  
S. T. Dunham
Keyword(s):  
Point Defect ◽  
Extended Defects ◽  
Dislocation Loops ◽  
Extended Defect ◽  
Enhanced Diffusion ◽  
Fundamental Model ◽  
Transient Enhanced Diffusion ◽  
Defect Evolution

Prediction of transient enhanced diffusion (TED) requires modeling of extended defects of many types, such as {311} defects, dislocation loops, boron-interstitial clusters, arsenic precipitates, etc. These extended defects not only form individually, but they also interact with each other through changes in point defect and solute concentrations. We have developed a fundamental model which can account for the behavior of a broad range of extended defects, as well as their interactions with each other. We have successfully applied and parameterized our model to a range of systems and conditions, some of which are presented in this paper.

Real-time in situ observation of extended defect evolution near a crack tip in GaSb crystal under thermal loading

2020 ◽  
Vol 515 ◽  
pp. 145934
Author(s):  
Yingbin Zhu ◽  
Huihui Wen ◽  
Hongye Zhang ◽  
Zhanwei Liu ◽  
Chao Liu ◽  
...  
Keyword(s):  
Real Time ◽  
Thermal Loading ◽  
Crack Tip ◽  
In Situ Observation ◽  
Extended Defect ◽  
Defect Evolution

Correlation of Dislocation Loop Formation and Time Dependent Diffusion of Implanted P-type Dopants in Gallium Arsenide

1991 ◽  
Vol 240 ◽  
Author(s):  
H. G. Robinson ◽  
M. D. Deal ◽  
D. A. Stevenson ◽  
K. S. Jones
Keyword(s):  
Gallium Arsenide ◽  
Time Dependence ◽  
Point Defect ◽  
Dislocation Loop ◽  
Time Dependent ◽  
Dislocation Loops ◽  
Loop Formation ◽  
Interstitial Diffusion ◽  
Order Of Magnitude ◽  
P Type

ABSTRACTRecent experimental results indicate that diffusion of implanted p-type dopants in GaAs is time dependent under certain conditions. For Mg implanted at a dose of 1 × 1014 cm−2, the diffusion is constant for approximately an hour, then decreases by an order of magnitude or more. Be implanted at 1 × 1013 and 1 ×1014 cm−2 exhibits similar behavior, but with a shorter time before the diffusivity decreases. The diffusivity in 1 × 1013 Mg cm−2 implants, in contrast, remains constant for up to 16 hours. TEM micrographs of Be and Mg implants reveal dislocation loops in the higher dose samples, but not in the lower dose ones. During annealing, the loops grow and decrease in density, eventually disappearing completely from the crystal. This annealing of the loops appears to correlate to the time dependence of the diffusion. This behavior can be explained in terms of the substitutional-interstitial diffusion (SID) mechanism and point defect equilibria.

In situ Transmission Electron Microscopy Investigation of Radiation Effects

2005 ◽  
Vol 20 (7) ◽  
pp. 1654-1683 ◽  
Author(s):  
R.C. Birtcher ◽  
M.A. Kirk ◽  
K. Furuya ◽  
G.R. Lumpkin ◽  
M-O. Ruault
Keyword(s):  
Radiation Effects ◽  
Ion Irradiation ◽  
Ion Beam ◽  
Ex Situ ◽  
In Situ Observation ◽  
Dislocation Loops ◽  
Transmission Electron ◽  
Microscopy Investigation ◽  
Ion Impact

In situ observation is of great value in the study of radiation damage utilizing electron or ion irradiation. We summarize the facilities and give examples of work found around the world. In situ observations of irradiation behavior have fallen into two broad classes. One class consists of long-term irradiation, with observations of microstructural evolution as a function of the radiation dose in which the advantage of in situ observation has been the maintenance of specimen position, orientation, and temperature. A second class has involved the recording of individual damage events in situations in which subsequent evolution would render the correct interpretation of ex situ observations impossible. In this review, examples of the first class of observation include ion-beam amorphization, damage accumulation, plastic flow, implant precipitation, precipitate evolution under irradiation, and damage recovery by thermal annealing. Examples of the second class of observation include single isolated ion impacts that produce defects in the form of dislocation loops, amorphous zones, or surface craters, and single ion impact-sputtering events. Experiments in both classes of observations attempt to reveal the kinetics underlying damage production, accumulation, and evolution.

Microstrucutural Characterization of RPV Steels Irradiated to High Fluences

2009 ◽  
Author(s):  
Minoru Tomimatsu ◽  
Hiroyuki Sakamoto ◽  
Kenji Dohi ◽  
Toshiyuki Watanabe ◽  
Hiroshi Matsuzawa
Keyword(s):  
Dislocation Loop ◽  
Structural Integrity ◽  
Neutron Radiation ◽  
Dislocation Loops ◽  
Loop Formation ◽  
Term Operation ◽  
Integrity Assessment ◽  
High Fluences ◽  
Water Reactors ◽  
Property Changes

Neutron radiation embrittlement of reactor pressure vessel (RPV) steels is one of critical issues for the structural integrity assessment of the RPVs. Especially, the embrittlement at high fluences is of great interest for the long term operation of light water reactors because information on the mechanical property changes as well as embrittlement mechanisms is limited at high fluences. In this study, microstructural analyses were conducted on the RPV steels irradiated to high fluences in order to confirm the applicability of the trend curve at high fluence region. Steels investigated are five base metals and a weld metal with their copper content ranging from 0.02 to 0.25 wt. %. These steels were irradiated in the material test reactors to fluence up to 1.3 × 1020 n/cm2, E > 1MeV, at temperature of about 290 °C. After irradiation, transmission electron microscope (TEM) observations were performed to characterize the nano-meter scale microstructural changes due to irradiation. Formation of dislocation loops was observed. Number density and diameter of dislocation loop was investigated. Effects of chemical composition of steel and fluence on dislocation loop formation are discussed.

scholarly journals Dislocation Loop Formation and Growth under In Situ Laser and/or Electron Irradiation

2011 ◽  
Vol 1 (1) ◽  
Author(s):  
Zhanbing Yang ◽  
Norihito Sakaguchi ◽  
Seiichi Watanabe ◽  
Masayoshi Kawai
Keyword(s):  
Dislocation Loop ◽  
Electron Irradiation ◽  
Loop Formation

Effets of surfaces on precipitate morphology in irradiated thin foils

1978 ◽  
Vol 36 (1) ◽  
pp. 654-655
Author(s):  
D.I. Potter ◽  
A. Taylor
Keyword(s):  
Ion Irradiation ◽  
Dark Field Image ◽  
Thin Foil ◽  
Dark Field ◽  
Al Alloy ◽  
Bright Field Image ◽  
Dislocation Loops ◽  
Precipitate Morphology ◽  
Thin Foils

Thermal aging of Ni-12.8 at. % A1 and Ni-12.7 at. % Si produces spatially homogeneous dispersions of cuboidal γ'-Ni3Al or Ni3Si precipitate particles arrayed in the Ni solid solution. We have used 3.5-MeV 58Ni+ ion irradiation to examine the effect of irradiation during precipitation on precipitate morphology and distribution. The nearness of free surfaces produced unusual morphologies in foils thinned prior to irradiation. These thin-foil effects will be important during in-situ investigations of precipitation in the HVEM. The thin foil results can be interpreted in terms of observations from bulk irradiations which are described first.Figure 1a is a dark field image of the γ' precipitate 5000 Å beneath the surface(∿1200 Å short of peak damage) of the Ni-Al alloy irradiated in bulk form. The inhomogeneous spatial distribution of γ' results from the presence of voids and dislocation loops which can be seen in the bright field image of the same area, Fig. 1b.

An in situ and ex situ TEM study of the formation of thin cobalt silicide films by molecular beam epitaxy on the silicon (100) surface

1988 ◽  
Vol 46 ◽  
pp. 884-885
Author(s):  
D. Loretto ◽  
J. M. Gibson ◽  
S. M. Yalisove ◽  
R. T. Tung
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Defect Density ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Ex Situ ◽  
Metal Base ◽  
In Situ Experiments ◽  
Potential Applications

The cobalt disilicide/silicon system has potential applications as a metal-base and as a permeable-base transistor. Although thin, low defect density, films of CoSi2 on Si(111) have been successfully grown, there are reasons to believe that Si(100)/CoSi2 may be better suited to the transmission of electrons at the silicon/silicide interface than Si(111)/CoSi2. A TEM study of the formation of CoSi2 on Si(100) is therefore being conducted. We have previously reported TEM observations on Si(111)/CoSi2 grown both in situ, in an ultra high vacuum (UHV) TEM and ex situ, in a conventional Molecular Beam Epitaxy system.The procedures used for the MBE growth have been described elsewhere. In situ experiments were performed in a JEOL 200CX electron microscope, extensively modified to give a vacuum of better than 10-9 T in the specimen region and the capacity to do in situ sample heating and deposition. Cobalt was deposited onto clean Si(100) samples by thermal evaporation from cobalt-coated Ta filaments.

Point Defect Absorption and Dislocation Loop Formation at Grain Boundaries in Hvem-Irradiated Zr and Its Alloys:1. Influence of Solute Addition

1985 ◽  
Vol 43 ◽  
pp. 350-351
Author(s):  
R.A. Herring ◽  
M. Griffiths ◽  
M.H Loretto ◽  
R.E. Smallman
Keyword(s):  
Grain Boundary ◽  
Grain Boundaries ◽  
Point Defect ◽  
Reactor Core ◽  
Solute Concentration ◽  
Nuclear Industry ◽  
Dislocation Loops ◽  
Loop Formation ◽  
Component Material ◽  
Impurity Interaction

Because Zr is used in the nuclear industry to sheath fuel and as structural component material within the reactor core, it is important to understand Zr's point defect properties. In the present work point defect-impurity interaction has been assessed by measuring the influence of grain boundaries on the width of the zone denuded of dislocation loops in a series of irradiated Zr alloys. Electropolished Zr and its alloys have been irradiated using an AEI EM7 HVEM at 1 MeV, ∼675 K and ∼10-6 torr vacuum pressure. During some HVEM irradiations it has been seen that there is a difference in the loop nucleation and growth behaviour adjacent to the grain boundary as compared with the mid-grain region. The width of the region influenced by the presence of the grain boundary should be a function of the irradiation temperature, dose rate, solute concentration and crystallographic orientation.

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