Treаtment of аluminа сerаmiсs by intense eleсtrоn аnd iоn beаms

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.

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Effects of ion-beam irradiation on the L10 phase transformation and their magnetic properties of FePt and PtMn films (Invited)

MRS Proceedings ◽

10.1557/proc-0887-q07-05 ◽

2005 ◽

Vol 887 ◽

Author(s):

Chih-Haung Lai ◽

Sheng-Huang Huang ◽

Cheng-Han Yang ◽

C.C. Chiang ◽

S. H. Liou ◽

...

Keyword(s):

Magnetic Properties ◽

Current Density ◽

Ion Irradiation ◽

Ion Beam ◽

Beam Current ◽

Spin Valves ◽

Beam Current Density ◽

High Coercivity ◽

Beam Irradiation ◽

Ion Beam Irradiation

ABSTRACTIon-beam irradiation shows enhancement or degradation of magnetic properties on L10 phase of FePt and PtMn films. A highly ordered L10 FePt phase was directly achieved by using 2 MeV He-ion irradiation without conventional postannealing. The in-plane coercivity greater than 5700 Oe can be obtained after disordered FePt films were irradiated at the beam current of several μA/cm2 with the ion does of 2.4×1016 ions/cm2. The high beam-current-density results in direct beam heating on samples. In addition, the irradiation-induced heating process provides efficient microscopic energy transfer and creates excess point defects, which significantly enhances the diffusion and promotes the formation of the ordered phase. Consequently, the direct ordering of FePt took place by using ion-irradiation heating at temperature as low as 230°C. The comparison has been made on the [Fe/Pt]10/C films by RTA and high current-density He irradiation. Although RTA and ion irradiation both reach high coercivity, ion irradiation seems to suppress the (001) texture, leading to isotropic Hc. Ion-beam irradiation can also be applied to the transformation of PtMn. An ordered PtMn phase, a large exchange field and a high GMR ratio (11%) were obtained in PtMn-based spin valves by using 1.25 μA/cm2 He-ions. On the other hand, Ge-ion and O-ion irradiation completely destroyed the ferromagnetism of FePt and GMR of PtMn-based spin valves, respectively. We propose a novel approach to achieve magnetic patterning by using ion irradiation, which can be applied for patterned media and magnetic sensors.

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Radiation damage studies of nuclear ceramics using the JANNUS-Saclay triple -ion beam irradiation platform

MRS Proceedings ◽

10.1557/opl.2011.374 ◽

2011 ◽

Vol 1298 ◽

Cited By ~ 2

Author(s):

P. Trocellier ◽

S. Miro ◽

Y. Serruys ◽

É. Bordas ◽

H. Martin ◽

...

Keyword(s):

Ion Irradiation ◽

Ion Beam ◽

Heavy Ion ◽

Ion Beams ◽

Beam Irradiation ◽

Ion Beam Irradiation ◽

Helium 4 ◽

Fusion Applications ◽

Ods Alloy ◽

Triple Ion

AbstractThe third accelerator of the multi-ion irradiation platform JANNUS (Joint Accelerators for Nanosciences and NUclear Simulation), a 6SDH-2 Pelletron from National Electrostatic Corporation, Middleton was installed at Saclay in October 2009. The first triple beam irradiation combining Fe, He and H ion beams has been performed in March 2010 on a Fe-12Cr model ODS alloy. In the first part of this paper, we give a technical description of the triple beam facility. Then, we present its performances and experimental capabilities. Typically, damage dose up to 100 dpa can be reached in 10 hours irradiation with heavy ion beams, with or without simultaneous bombardment by protons, helium-4 ions or any other heavy ion beam. In the second part of this paper, we illustrate some recent experiments relative to advanced nuclear ceramics and composite materials developed in the frame of the Generation IV Forum research program or for fusion applications.

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Growth of Cu-Oxide Protrusion by Ar Ion Irradiation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.558-559.1359 ◽

2007 ◽

Vol 558-559 ◽

pp. 1359-1362 ◽

Cited By ~ 2

Author(s):

Hiroyuki Tanaka ◽

Shunichiro Tanaka

Keyword(s):

Ion Irradiation ◽

Ion Beam ◽

Beam Irradiation ◽

Ion Beam Irradiation ◽

Residual Oxygen ◽

Irradiation Angle ◽

Oxygen Atoms

Cu2O conical micron-scale protrusions have been grown on a preoxidized Cu surface by the Ar ion beam irradiation at 9 kV for 5-20 min in the low vacuum. This Ar ion irradiation is based on the ‘Transcription Method’ which has been originated by B.-S. Xu and S.-I. Tanaka in 1996 to form nanoparticles. Ar ion irradiation induced needle-like nanostructures composed of Cu2O and CuO which were randomly nucleated on Cu surface by the oxidation at 623 K for 10 min in the air. The obtained Cu2O conical protrusions have a controllable length of up to 14.6 μm with diameter in the range of 0.8 μm by changing the Ar ion irradiation angle to the surface. The mechanism of the formation of the conical protrusions is proposed that Cu atoms on the Cu surface activated and sputtered by the Ar ion irradiation diffuse on the surface of needle-like oxide as nuclei along the Ar ion track and react with residual oxygen atoms to grow the conical Cu2O protrusions.

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Spontaneous formation of nanometer-scale self-organized structures in Ag-Cu alloys under irradiation

MRS Proceedings ◽

10.1557/proc-647-o7.1 ◽

2000 ◽

Vol 647 ◽

Author(s):

Raúl A. Enrique ◽

Pascal Bellon

Keyword(s):

Ion Irradiation ◽

Ion Beam ◽

Solute Concentration ◽

Irradiation Temperature ◽

Nanometer Scale ◽

Beam Irradiation ◽

X Ray Diffraction ◽

Ion Beam Irradiation ◽

Self Organized ◽

The One

AbstractIon-beam irradiation can be used as a processing tool to synthesize metastable materials. A particular case is the preparation of solid solutions from immiscible alloys, which have been achieved for a whole range of systems. In this process, enhanced solute concentration is obtained through the local mixing induced by each irradiation event, which if occurring at a high enough frequency, can outweigh demixing by thermal diffusion. The resulting microstructure forms in far from equilibrium conditions, and theoretical results for these kind of driven alloys have shown that novel microstructures exhibiting self-organization can develop. To test these predictions, we prepare Ag-Cu multilayered thin films that we subject to 1 MeV Kr+-ion irradiation at temperatures ranging from room temperature to 225 °C, and characterize the specimens by x-ray diffraction, TEM and STEM. We observe two different phenomena occurring at different length scales: On the one hand, regardless of the irradiation temperature, grains grow under irradiation until reaching a size limited by film thickness (~200 nm). On the other hand, the distribution of species inside the grains is greatly affected by the irradiation temperature. At intermediate temperatures, a semi-coherent decomposition is observed at a nanometer scale. This nanometer-scale decomposition phenomenon appears as an evidence of patterning, and thus confirms on the possibility of using ion-beam irradiation as a route to synthesize nanostructured materials with novel magnetic and optical properties.

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Fabrication of Nanopore in MoS2-Graphene vdW Heterostructure by Ion Beam Irradiation and the Mechanical Performance

Nanomaterials ◽

10.3390/nano12020196 ◽

2022 ◽

Vol 12 (2) ◽

pp. 196

Author(s):

Xin Wu ◽

Ruxue Yang ◽

Xiyue Chen ◽

Wei Liu

Keyword(s):

Mechanical Performance ◽

Ion Irradiation ◽

Ion Beam ◽

Tensile Tests ◽

Uniaxial Tensile ◽

Beam Irradiation ◽

Ion Beam Irradiation ◽

Stacking Order ◽

Vdw Heterostructure ◽

Nanopore Structure

Nanopore structure presents great application potential especially in the area of biosensing. The two-dimensional (2D) vdW heterostructure nanopore shows unique features, while research around its fabrication is very limited. This paper proposes for the first time the use of ion beam irradiation for creating nanopore structure in 2D vdW graphene-MoS2 heterostructures. The formation process of the heterostructure nanopore is discussed first. Then, the influence of ion irradiation parameters (ion energy and ion dose) is illustrated, based on which the optimal irradiation parameters are derived. In particular, the effect of stacking order of the heterostructure 2D layers on the induced phenomena and optimal parameters are taken into consideration. Finally, uniaxial tensile tests are conducted by taking the effect of irradiation parameters, nanopore size and stacking order into account to demonstrate the mechanical performance of the heterostructure for use under a loading condition. The results would be meaningful for expanding the applications of heterostructure nanopore structure, and can arouse more research interest in this area.

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Amortization and Recrystallization of 6H-SiC by ion Beam Irradiation

MRS Proceedings ◽

10.1557/proc-339-197 ◽

1994 ◽

Vol 339 ◽

Cited By ~ 4

Author(s):

V. Heera ◽

R. Kögler ◽

W. Skorupa ◽

J. Stoemenos

Keyword(s):

Ion Irradiation ◽

Ion Beam ◽

Surface Region ◽

Ion Beam Irradiation ◽

Surface Layers ◽

Near Surface ◽

Transmission Electron ◽

Amorphous Surface ◽

Amorphous Sic

ABSTRACTThe evolution of the damage in the near surface region of single crystalline 6H-SiC generated by 200 keV Ge+ ion implantation at room temperature (RT) was investigated by Rutherford backscattering spectroscopy/chanelling (RBS/C). The threshold dose for amorphization was found to be about 3 · 1014 cm-2, Amorphous surface layers produced with Ge+ ion doses above the threshold were partly annealed by 300 keV Si+ ion beam induced epitaxial crystallization (IBIEC) at a relatively low temperature of 480°C For comparison, temperatures of at least 1450°C are necessary to recrystallize amorphous SiC layers without assisting ion irradiation. The structure and quality of both the amorphous and recrystallized layers were characterized by cross-section transmission electron microscopy (XTEM). Density changes of SiC due to amorphization were measured by step height measurements.

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Photoluminescence enhancement and high accuracy patterning of lead halide perovskite single crystals by MeV ion beam irradiation

Journal of Materials Chemistry C ◽

10.1039/d0tc02326d ◽

2020 ◽

Vol 8 (29) ◽

pp. 9923-9930 ◽

Cited By ~ 1

Author(s):

Milan Palei ◽

M. Motapothula ◽

Aniruddha Ray ◽

Ahmed L. Abdelhady ◽

Luca Lanzano ◽

...

Keyword(s):

Single Crystals ◽

Ion Irradiation ◽

Ion Beam ◽

High Accuracy ◽

Enhancement Effect ◽

Beam Irradiation ◽

Ion Beam Irradiation ◽

Photoluminescence Enhancement ◽

Halide Perovskite ◽

Lead Halide

Using MeV ion irradiation, a PL enhancement effect of MAPbBr3 single crystals is demonstrated.

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Formation Mechanism of Micro- and Nanocrystalline Surface Layers in Titanium and Aluminum Alloys in Electron Beam Irradiation

Metals ◽

10.3390/met10101399 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1399

Author(s):

Sergei Nevskii ◽

Vladimir Sarychev ◽

Sergey Konovalov ◽

Alexey Granovskii ◽

Victor Gromov

Keyword(s):

Mathematical Model ◽

Electron Beam ◽

Field Strength ◽

Electron Beam Irradiation ◽

Electron Beams ◽

Hydrodynamic Instabilities ◽

Beam Irradiation ◽

Surface Layers ◽

Reported Study ◽

Capillary Evaporation

The reported study discusses the formation of micro- and nanocrystalline surface layers in alloys on the example of Ti-Y and Al-Si-Y systems irradiated by electron beams. The study has established a crystallization mechanism of molten layers in the micro-and nanodimensional range, which involves a variety of hydrodynamic instabilities developing on the plasma–melt interface. As suggested, micro- and nanostructures form due to the combination of thermocapillary, concentration and capillary, evaporation and capillary and thermoelectric instabilities. This mechanism has provided the foundation for a mathematical model to describe the development of structures in focus in the electron beam irradiation. The study has pointed out that thermoelectric field strength E ≥ 106 V/m is attributed to the occurring combination of instabilities in micro- and nanodimensional ranges. A full dispersion equation of perturbations on the melt surface was analyzed.

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Ion beam profiling from the interaction with a freestanding 2D layer

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.8.73 ◽

2017 ◽

Vol 8 ◽

pp. 682-687 ◽

Cited By ~ 4

Author(s):

Ivan Shorubalko ◽

Kyoungjun Choi ◽

Michael Stiefel ◽

Hyung Gyu Park

Keyword(s):

Focused Ion Beam ◽

Ion Beam ◽

Beam Current ◽

Exposure Dose ◽

Ion Beams ◽

Gaussian Profile ◽

Helium Ion ◽

Spread Function ◽

Sputtering Yields ◽

Pattern Resolution

Recent years have seen a great potential of the focused ion beam (FIB) technology for the nanometer-scale patterning of a freestanding two-dimensional (2D) layer. Experimentally determined sputtering yields of the perforation process can be quantitatively explained using the binary collision theory. The main peculiarity of the interaction between the ion beams and the suspended 2D material lies in the absence of collision cascades, featured by no interaction volume. Thus, the patterning resolution is directly set by the beam diameters. Here, we demonstrate pattern resolution beyond the beam size and precise profiling of the focused ion beams. We find out that FIB exposure time of individual pixels can influence the resultant pore diameter. In return, the pore dimension as a function of the exposure dose brings out the ion beam profiles. Using this method of determining an ion-beam point spread function, we verify a Gaussian profile of focused gallium ion beams. Graphene sputtering yield is extracted from the normalization of the measured Gaussian profiles, given a total beam current. Interestingly, profiling of unbeknown helium ion beams in this way results in asymmetry of the profile. Even triangular beam shapes are observed at certain helium FIB conditions, possibly attributable to the trimer nature of the beam source. Our method of profiling ion beams with 2D-layer perforation provides more information on ion beam profiles than the conventional sharp-edge scan method does.

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Modification of Strength Properties of Oxide Materials by Ion Irradiation

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.781.70 ◽

2018 ◽

Vol 781 ◽

pp. 70-75

Author(s):

Sergei Ghyngazov ◽

Valeria Kostenko ◽

Sergey Shevelev ◽

Anatoliy I. Kupchishin ◽

Aleksey Kondratyuk

Keyword(s):

Magnesium Oxide ◽

Ion Irradiation ◽

Ion Beam ◽

Strength Properties ◽

Critical Stress Intensity Factor ◽

Ceramic Technology ◽

Surface Layers ◽

Nanosecond Duration ◽

Near Surface ◽

Moderate Power

The effect of ion irradiation on the strength characteristics of magnesium oxide and ceramics based on zirconia is studied. The MgO samples were a single crystal grown in an artificial manner. Samples of zirconium ceramics were prepared by ceramic technology. Irradiation of MgO crystals was carried out by Si+ ions (E = 150 keV), Fe+ (E = 70 keV), C+ (E = 50 keV) at room temperature. The fluence varied within the range (1016–1017) сm–2. The modification of the investigated types of ceramics was carried out by ions Al+ (Е = 60 keV), Ar+ (Е= 60 keV), N+ (E = 50 keV). We used ion beams of microsecond duration and moderate power (the current density in the pulse was 3 10-3 A/cm2). Fluence was 1017 cm-2. The irradiation of the ceramics with an ion beam C+ (E = 50 keV) was also performed with nanosecond duration (τ = 50 ns). It is established that ionic irradiation of magnesium oxide leads to an increase in crack resistance and a critical stress intensity factor. Irradiation of ceramics leads to hardening of its near-surface layers.

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