Fundamentals and Present Aspects of Ion Beam Technology. V. Application of Ion Beam. 4. Application to Life Science. 4.2. Biological effects of ion beams.

Biological effects of ion beams with different ranges and linear energy transfers (LETs) were investigated in Nicotiana tabacum L. Mature pollen was exposed to doses of 1400 Gy of 6 MeV4He2+ or 1000 Gy of 50 MeV 4He2+, 15 MeV 12C4+, or 460 MeV 40Ar13+ and used to pollinate non-irradiated flowers (I0 generation), resulting in I, seeds. I1 plants were self-pollinated, and mutations were analyzed in the I2 generation. Seed formation in the I0 generation was greatly reduced in all treatments except where 12C4+ irradiated pollen was used. Germination rate and survival rate in the I1 generation were also reduced in the seeds generated from crosses with pollen irradiated with 6 MeV 4He2+ and 12C4+ beams. Furthermore, chromosome and morphological aberrations in I1 plants were observed. However, in 50 MeV 4He2+ and 40Ar13+ regimes, no seeds germinated. In the I2 generation, chlorophyll mutants were very scarce. Morphological mutants were obtained at a frequency of 5.7 × 10−3 and 7.9 × 10−3 in the progeny of 6 MeV 4He2+ and 12C4+ regimes, respectively. It is concluded that the penetration depth is important for inducing mutation and also that pollen can be used for obtaining mutations induced by ion beams with very short penetration depths. Key words: ion beam, mutation, Nicotiana tabacum, pollen.

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Fundamentals and Present Aspects of Ion Beam Technology. V. Application of Ion Beam. 4. Application to Life Science. 4.1. Biological effect of ion beams with emphasis on the early stages of radiation action.

RADIOISOTOPES ◽

10.3769/radioisotopes.44.11_806 ◽

1995 ◽

Vol 44 (11) ◽

pp. 806-811

Author(s):

Tan TAKAHASHI

Keyword(s):

Biological Effect ◽

Life Science ◽

Ion Beam ◽

Ion Beams ◽

Early Stages ◽

Radiation Action

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Preparation of TEM samples by focused ion beams

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138968 ◽

1995 ◽

Vol 53 ◽

pp. 518-519

Author(s):

John F. Walker ◽

J C Reiner ◽

C Solenthaler

Keyword(s):

Integrated Circuit ◽

Polycrystalline Silicon ◽

Field Effect Transistor ◽

High Spatial Resolution ◽

Ion Beam ◽

Ion Beams ◽

Focused Ion Beams ◽

Precise Location ◽

Effect Transistor ◽

Circuit Technology

The high spatial resolution available from TEM can be used with great advantage in the field of microelectronics to identify problems associated with the continually shrinking geometries of integrated circuit technology. In many cases the location of the problem can be the most problematic element of sample preparation. Focused ion beams (FIB) have previously been used to prepare TEM specimens, but not including using the ion beam imaging capabilities to locate a buried feature of interest. Here we describe how a defect has been located using the ability of a FIB to both mill a section and to search for a defect whose precise location is unknown. The defect is known from electrical leakage measurements to be a break in the gate oxide of a field effect transistor. The gate is a square of polycrystalline silicon, approximately 1μm×1μm, on a silicon dioxide barrier which is about 17nm thick. The break in the oxide can occur anywhere within that square and is expected to be less than 100nm in diameter.

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Atomic force microscopy (AFM) of the topography of silicon surfaces exposed to ion beams

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130298 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1132-1133

Author(s):

Mark Denker ◽

Jennifer Wall ◽

Mark Ray ◽

Richard Linton

Keyword(s):

Secondary Ion Mass Spectrometry ◽

Incidence Angle ◽

Ion Beam ◽

Depth Profiling ◽

Depth Resolution ◽

Ion Beams ◽

Scanning Tunneling ◽

Tunneling Microscopy ◽

Trace Impurities ◽

Energy Dose

Reactive ion beams such as O2+ and Cs+ are used in Secondary Ion Mass Spectrometry (SIMS) to analyze solids for trace impurities. Primary beam properties such as energy, dose, and incidence angle can be systematically varied to optimize depth resolution versus sensitivity tradeoffs for a given SIMS depth profiling application. However, it is generally observed that the sputtering process causes surface roughening, typically represented by nanometer-sized features such as cones, pits, pyramids, and ripples. A roughened surface will degrade the depth resolution of the SIMS data. The purpose of this study is to examine the relationship of the roughness of the surface to the primary ion beam energy, dose, and incidence angle. AFM offers the ability to quantitatively probe this surface roughness. For the initial investigations, the sample chosen was <100> silicon, and the ion beam was O2+.Work to date by other researchers typically employed Scanning Tunneling Microscopy (STM) to probe the surface topography.

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Chemical Precursors for GaAs Etching with low Energy ion Beams: Chlorine adsorption on GaAs(100)

MRS Proceedings ◽

10.1557/proc-223-215 ◽

1991 ◽

Vol 223 ◽

Cited By ~ 3

Author(s):

Richard B. Jackman ◽

Glenn C. Tyrrell ◽

Duncan Marshall ◽

Catherine L. French ◽

John S. Foord

Keyword(s):

Ion Beam ◽

Ion Beams ◽

Low Energy ◽

Ion Beam Etching ◽

Chlorine Adsorption

ABSTRACTThis paper addresses the issue of chlorine adsorption on GaAs(100) with respect to the mechanisms of thermal and ion-enhanced etching. The use of halogenated precursors eg. dichloroethane is also discussed in regard to chemically assisted ion beam etching (CAIBE).

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Yttrium Oxide Freeze-Casts: Target Materials for Radioactive Ion Beams

Materials ◽

10.3390/ma14112864 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2864

Author(s):

Eva Kröll ◽

Miriana Vadalà ◽

Juliana Schell ◽

Simon Stegemann ◽

Jochen Ballof ◽

...

Keyword(s):

Pore Structure ◽

Yttrium Oxide ◽

Ion Beam ◽

Isotope Separation ◽

Target Material ◽

Ion Beams ◽

Radioactive Isotopes ◽

Solid Loading ◽

Radioactive Ion Beams ◽

Freeze Casting

Highly porous yttrium oxide is fabricated as ion beam target material in order to produce radioactive ion beams via the Isotope Separation On Line (ISOL) method. Freeze casting allows the formation of an aligned pore structure in these target materials to improve the isotope release. Aqueous suspensions containing a solid loading of 10, 15, and 20 vol% were solidified with a unidirectional freeze-casting setup. The pore size and pore structure of the yttrium oxide freeze-casts are highly affected by the amount of solid loading. The porosity ranges from 72 to 84% and the crosslinking between the aligned channels increases with increasing solid loading. Thermal aging of the final target materials shows that an operation temperature of 1400 °C for 96 h has no significant effect on the microstructure. Thermo-mechanical calculation results, based on a FLUKA simulation, are compared to measured compressive strength and forecast the mechanical integrity of the target materials during operation. Even though they were developed for the particular purpose of the production of short-lived radioactive isotopes, the yttria freeze-cast scaffolds can serve multiple other purposes, such as catalyst support frameworks or high-temperature fume filters.

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Production of ion beams in high-power laser–plasma interactions and their applications

Laser and Particle Beams ◽

10.1017/s0263034604221048 ◽

2004 ◽

Vol 22 (1) ◽

pp. 19-24 ◽

Cited By ~ 21

Author(s):

F. PEGORARO ◽

S. ATZENI ◽

M. BORGHESI ◽

S. BULANOV ◽

T. ESIRKEPOV ◽

...

Keyword(s):

Laser Pulse ◽

Medical Physics ◽

Ion Beam ◽

Laser Pulses ◽

Ion Beams ◽

Laser Plasma Interactions ◽

Physical Mechanisms ◽

Short Laser Pulses ◽

Laser Pulse Intensity ◽

Target Design

Energetic ion beams are produced during the interaction of ultrahigh-intensity, short laser pulses with plasmas. These laser-produced ion beams have important applications ranging from the fast ignition of thermonuclear targets to proton imaging, deep proton lithography, medical physics, and injectors for conventional accelerators. Although the basic physical mechanisms of ion beam generation in the plasma produced by the laser pulse interaction with the target are common to all these applications, each application requires a specific optimization of the ion beam properties, that is, an appropriate choice of the target design and of the laser pulse intensity, shape, and duration.

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