Changing the Structural State of Amorphous Silicon by Ion Irradiation

1989 ◽  
Vol 157 ◽  
Author(s):  
S. Roorda ◽  
W.C. Sinke ◽  
J.M. Poate ◽  
D.C. Jacobson ◽  
S. Dierker ◽  
...  
Keyword(s):  
Structural Relaxation ◽  
Ion Irradiation ◽  
Ion Beam ◽  
Ion Beams ◽  
Nuclear Collision ◽  
Important Ingredient ◽  
Scanning Calorimetry ◽  
Amorphous Si ◽  
Induced Defects ◽  
Kinetics Of

ABSTRACTIon beams of keV and MeV energies have been used to bombard amorphous Si (a-Si), which had previously been annealed (‘relaxed’). Analysis by Raman spectroscopy and differential scanning calorimetry shows that when 1 out of every 20 Si atoms is displaced by a nuclear collision, the a-Si returns to its unrelaxed state and cannot be distinguished from as implanted a-Si. Moreover, the kinetics of the heat release on annealing of similarly bombarded crystalline Si (c-Si) are qualitatively identical to those of structural relaxation in a-Si. This implies that the population of ion beam induced defects in a-Si is very similar to that in c-Si. It also shows that defect annihilation is an important ingredient in the mechanism of structural relaxation of a-Si.

Viscosity, Structural Relaxation and Defect Annihilation Kinetics of Amorphous Si

1990 ◽  
Vol 205 ◽  
Author(s):  
Ann Witvrouw ◽  
Frans Spaepen
Keyword(s):  
Viscous Flow ◽  
Structural Relaxation ◽  
Activation Enthalpy ◽  
Ion Beam ◽  
Time Characteristic ◽  
Annihilation Process ◽  
Dangling Bonds ◽  
Curvature Measurements ◽  
Amorphous Si ◽  
Kinetics Of

AbstractSubstrate curvature measurements were used to monitor viscous flow in ion beam sputtered amorphous Si for temperatures ranging from 150 to 400 °C. The viscosity increases linearly with time, characteristic of a bimolecular defect annihilation process. This is consistent with the defects governing viscous flow being dangling bonds. The isoconfigurational activation enthalpy for the viscosity is 1.8 ±.3 eV.

Thermodynamic and Structural Properties of Mev Ion Beam Amorphized Silicon

1989 ◽  
Vol 157 ◽  
Author(s):  
S. Roorda ◽  
W.C. Sinke ◽  
J.M. Poate ◽  
D.C. Jacobson ◽  
P. Fuoss ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Raman Spectroscopy ◽  
Structural Properties ◽  
Atomic Structure ◽  
Structural Relaxation ◽  
Ion Beam ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Amorphous Si

ABSTRACTThermodynamic and structural properties of amorphous Si (a-Si), prepared by MeV 28Si+-ion implantation are investigated by differential scanning calorimetry, Raman spectroscopy and X-ray diffraction. The influence of thermal annealing below 500 °C on a-Si is investigated with these different probes. The observed changes result from structural relaxation. Raman spectroscopy and X-ray diffraction show that structural relaxation is accompanied by changes in the average atomic structure.

Ion-Beam-Induced Epitaxy and Solute Segregation at the Si Crystal-Amorphous Interface

1988 ◽  
Vol 128 ◽  
Author(s):  
J. M. Poate ◽  
D. C. Jacobson ◽  
F. Priolo ◽  
Michael O. Thompson
Keyword(s):  
Crystal Growth ◽  
Growth Process ◽  
Ion Beam ◽  
Solute Segregation ◽  
Ion Beams ◽  
Temperature Range ◽  
Crystal Growth Process ◽  
Amorphous Si ◽  
And Diffusion ◽  
Diffusion Of Impurities

ABSTRACTSegregation and diffusion of impurities in amorphous Si during furnace and ion-beam-induced epitaxy will be discussed. The use of ion beams to enhance the crystal growth process has resulted in novel behavior for fast diffusers such as Au. Diffusion is enhanced in the temperature range 300–700 K with activation energies ∼0.3 eV. Segregation and trapping are analogous to behavior at liquid-solid interfaces

Amorphization Kinetics of Zr (Cr,Fe)2 Under Ion Irradiation

1992 ◽  
Vol 279 ◽  
Author(s):  
A. T. Motta ◽  
L. M. Howe ◽  
P. R. Okamoto
Keyword(s):  
Neutron Irradiation ◽  
Ion Irradiation ◽  
Ion Beam ◽  
National Laboratory ◽  
Argonne National Laboratory ◽  
Matrix Interface ◽  
Thin Foils ◽  
Intermetallic Precipitates ◽  
Kinetics Of

ABSTRACTThin foils of Zircaloy-4 were irradiated with 350 KeV 40Ar ions in the dual ion beam/HVEM facility at Argonne National Laboratory at 300 – 650 K. The irradiation-induced araorphization of the intermetallic precipitates Zr (Cr, Fe)2 and Zr2 (Ni, Fe) was studied in situ. For Zr (Cr,Fe)2 precipitates the dose-to-amorphization was found to increase exponentially with temperature, with a critical temperature of about 650 K. The amorphization morphology was shown to be homogeneous, with no preferential site for nucleation, in contrast to neutron-irradiation amorphization which started at the precipitate-matrix interface. For Zr2 (Ni,Fe) precipitates it was found that amorphization occurred at 550 K and 600 K, whereas in neutron irradiation no amorphization has been observed at those temperatures. The results are discussed in the context of the previous experimental results of neutron and electron irradiation and likely amorphization mechanisms are proposed.

Ion beam mutagenesis - an innovative and effective method for plant breeding and gene discovery.

2021 ◽  
pp. 411-423
Author(s):  
Tomoko Abe ◽  
Hiroyuki Ichida ◽  
Yoriko Hayashi ◽  
Ryouhei Morita ◽  
Yuki Shirakawa ◽  
...  
Keyword(s):  
Plant Breeding ◽  
Ion Irradiation ◽  
Ion Beam ◽  
Single Gene ◽  
Heavy Ion ◽  
Ion Beams ◽  
Mutation Induction ◽  
Chemical Research ◽  
Large Deletions ◽  
Ri Beam

Abstract We have developed a unique technology for mutation induction of plants using energetic ion beams at the RI Beam Factory (RIBF) of Rikagaku Kenkyūjo (RIKEN) (Institute of Physical and Chemical Research). Ion beams effectively induce mutations at relatively low doses without severely inhibiting growth. The irradiation treatment can be given to various plant materials and mutation can be induced in a short time, between seconds and a few minutes. The linear energy transfer (LET) of ions depends on the nuclide and velocity. Since LET value affects the mutation frequency, it is an important parameter to determine the most effective irradiation condition in mutagenesis. We determined the most effective dose in each LET for mutation induction in imbibed rice seeds. Subsequently, we analysed the mutated DNA responsible for the phenotype in morphological mutants. Most of the mutations were small deletions of less than 100 bp. Irradiations of C-ions and Ne-ions are effective for plant breeding because of the very high mutation rate and sufficient energy to disrupt a single gene. On the other hand, all mutations induced by Ar-ion (290 keV/μm) irradiation were large deletions ranging from 176 bp to approximately 620 kb. The average number of mutations in the target exon regions was 7.3, 8.5 and 4.3 per M3 mutant plant in C-ions, Ne-ions and Ar-ions, respectively. The number of mutations induced by heavy-ion irradiation was relatively small. We could identify six responsible genes for eight mutants induced by C-ion and Ne-ion irradiations and two responsible genes for four mutants induced by Ar-ion irradiation. Three of these were genes not previously described.

Treаtment of аluminа сerаmiсs by intense eleсtrоn аnd iоn beаms

2021 ◽  
Vol 102 (2) ◽  
pp. 50-55
Author(s):  
S.А. Ghyngаzоv ◽  
◽  
V.А. Kоstenkо ◽  
S.V. Matrenin ◽  
A.I. Kupchishin ◽  
...  
Keyword(s):  
Electron Beam Irradiation ◽  
Ion Irradiation ◽  
Ion Beam ◽  
Beam Current ◽  
Ion Beams ◽  
Ceramic Surface ◽  
Carbon Ions ◽  
Alumina Ceramics ◽  
Beam Irradiation ◽  
Surface Layers

The paper investigated modification of the microstructure of the surface layers of alumina ceramics under exposure to electron and ion beams. Electron beam irradiation was performed at accelerating voltage U = 15 kV and beam current of J = 70 A and J = 100 A. Ion irradiation was performed with carbon ions at accelerating voltage of U = 180 keV. The current density and energy density varied in the range of 15–85 A/cm2 and 0.3–1.5 J/cm2 , respectively. The amount of energy acting on the ceramic surface depended on the number of pulses N. It is shown that exposure to electron and ion beams changes the microstructure of the irradiated ceramic layer. In general, the effect of exposure is similar for electron and ion irradiation, and it is characterized not only by surface melting, but also by formation of a finer microstructure through the depth of the irradiated layer, which is oriented in the direction of the electron and ion beam exposure. It is shown that crystallization processes in overheated layers of ceramics depend on its type and melting point.

Ion Beam Induced Structural and Electrical Modifications in Crystalline and Amorphous Silicon

1993 ◽  
Vol 316 ◽  
Author(s):  
S. Coffa ◽  
A. Battaglia ◽  
F. Priolo
Keyword(s):  
Deep Level Transient Spectroscopy ◽  
Ion Irradiation ◽  
Deep Level ◽  
Ion Beam ◽  
Defect Structures ◽  
Transmission Electron ◽  
Defect Accumulation ◽  
Amorphous Si ◽  
Transient Spectroscopy

ABSTRACTThe mechanisms of defect accumulation and dynamic annealing in ion-implanted crystalline and amorphous Si are elucidated by performing conductivity and Raman spec-trascopy measurements in-situ during ion irradiation. In amorphous Si the entire gamut of defect structures has been characterized by analyzing the annealing kinetics from 77 K to ~ 800 K both during and after irradiation. Moreover the modifications in the electronic properties of crystalline Si produced by ion-irradiation have been investigated. The use of in-situ techniques in combination with transmission electron microscopy and deep-level transient spectroscopy allowed us to demonstrate the correlation between structural and electrical defects produced by ion-irradiation in Si.

Ion beam synthesis of nitride layers in iron

1992 ◽  
Vol 7 (10) ◽  
pp. 2689-2712 ◽  
Author(s):  
A.M. Vredenberg ◽  
C.M. Pérez-Martin ◽  
J.S. Custer ◽  
D.O. Boerma ◽  
L. de Wit ◽  
...  
Keyword(s):  
Ion Beam ◽  
High Energy ◽  
Nitride Layer ◽  
Layer Growth ◽  
Stable Phase ◽  
Iron Nitride ◽  
High Dose ◽  
Nitride Layers ◽  
Induced Defects ◽  
Kinetics Of

Stoichiometric iron nitride layers have been synthesized by high dose, high energy nitrogen implantation into Fe using a two-step implantation process. First, a nitrogen preimplantation at ~100 °C is used to form nitride precipitates. A low temperature is necessary to restrict the nitrogen mobility. Second, 1 MeV implantation at ~300 °C leads to the formation of a stoichiometric γ′–Fe4N layer at the position of the preimplanted N atoms. Growth of this nitride layer proceeds by diffusion of the implanted N through either the α–Fe matrix (for 200 or 500 keV preimplantations) or the nitride layer itself (for 1 MeV preimplantation). During annealing above 350 °C the γ′ layers dissolve in a planar fashion, characterized by an activation energy of 2.3 eV. Phase formation during preimplantation and phase transformations during subsequent annealing or hot implantation can be understood from the thermodynamics for the Fe–N system, while the kinetics of layer growth is influenced by the beam-induced defects. The experiment and model suggest that γ′ is not a thermodynamically stable phase below 310 ± 10 °C and should decompose into α (ferrite) and ∊ nitride.

Crystal Nucleation in Amorphous Si Thin Films During Ion Irradiation

1990 ◽  
Vol 187 ◽  
Author(s):  
James S. Im ◽  
Harry A. Atwater
Keyword(s):  
Nucleation Rate ◽  
Ion Irradiation ◽  
High Energy ◽  
Crystal Nucleation ◽  
Transmission Electron ◽  
Crystal Transition ◽  
Amorphous Si ◽  
Si Films ◽  
Kinetics Of

AbstractThe nucleation and transformation kinetics of the amorphous-to-crystal transition in Si films under 1.5 MeV Xe+ irradiation have been investigated by means of in situ transmission electron microscopy in the temperature range T = 480–580°C. After an incubation period during which negligible nucleation occurs, a constant nucleation rate was observed in steady state, suggesting homogeneous nucleation. A significant enhancement in nucleation rate during high energy ion irradiation (6 orders of magnitude) was observed as compared with thermal crystallization, with an apparent activation energy of Qn = 3.9 ± 0.75 eV. Independent analyses of the temperature dependence of the incubation time, the crystal growth rate, and nucleation rate suggest that interface rearrangement kinetics and not the thermodynamic barrier to crystallization, are affected by ion irradiation.

scholarly journals IMITATING NEUTRON IRRADIATION DAMAGE USING A COMBINATION OF ION BEAMS

2018 ◽  
Vol 14 ◽  
pp. 42
Author(s):  
Václav Šísl ◽  
Martin Ševeček
Keyword(s):  
Neutron Irradiation ◽  
Nuclear Reactor ◽  
Ion Irradiation ◽  
Ion Beams ◽  
Third Party ◽  
Irradiation Damage ◽  
Material Structure ◽  
Monte Carlo Code ◽  
The One ◽  
Induced Defects

There is a strong motivation for using ion beams to imitate neutron irradiation damage, mainly in order to reduce costs and time demands linked to neutron irradiation experiments. The long-term goal of the authors is to create an ion irradiation methodology, which could be employed in the development process of innovative nuclear fuel materials. This methodology will be based on combining of a set of ion beams in such a way that the final distribution of irradiation-induced defects in the material structure is similar to the one which would have been introduced by neutrons in a nuclear reactor. The first part of the methodology is represented by an optimization tool described here. The tool uses a third party Monte Carlo code SRIM to simulate ion transport in a target and to determine the distribution of radiation damage. Subsequently, a custom genetic optimization algorithm is applied to a set of damage distribution profiles to find their optimal combination.

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