Observation of threshold energy and hysteresis in high current ion beam guiding and transmission through a micro-glass-capillary

The High Current Experiment (HCX) is being assembled at Lawrence Berkeley National Laboratory as part of the U.S. program to explore heavy ion beam transport at a scale representative of the low-energy end of an induction linac driver for fusion energy production. The primary mission of this experiment is to investigate aperture fill factors acceptable for the transport of space-charge dominated heavy ion beams at high space-charge intensity (line-charge density ∼ 0.2 μC/m) over long pulse durations (>4 μs). This machine will test transport issues at a driver-relevant scale resulting from nonlinear space-charge effects and collective modes, beam centroid alignment and beam steering, matching, image charges, halo, lost-particle induced electron effects, and longitudinal bunch control. We present the first experimental results carried out with the coasting K+ ion beam transported through the first 10 electrostatic transport quadrupoles and associated diagnostics. Later phases of the experiment will include more electrostatic lattice periods to allow more sensitive tests of emittance growth, and also magnetic quadrupoles to explore similar issues in magnetic channels with a full driver scale beam.

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Investigation of ion beam induced nanopattern formation near the threshold energy

Applied Physics Letters ◽

10.1063/1.4825280 ◽

2013 ◽

Vol 103 (16) ◽

pp. 161602 ◽

Cited By ~ 10

Author(s):

Amaresh Metya ◽

Debabrata Ghose

Keyword(s):

Ion Beam ◽

Threshold Energy

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Defects and AlSb Precipitate Nucleation in Laser Irradiated Aluminum

MRS Proceedings ◽

10.1557/proc-4-401 ◽

1981 ◽

Vol 4 ◽

Cited By ~ 3

Author(s):

P. S. Peercy ◽

D. M. Follstaedt ◽

S. T. Picraux ◽

W. R. Wampler

Keyword(s):

Room Temperature ◽

Laser Energy ◽

Ion Beam ◽

Threshold Energy ◽

Single Pulse ◽

Temperature Profiles ◽

Beam Analysis ◽

Slip Deformation ◽

Precipitate Nucleation ◽

Substrate Temperatures

ABSTRACTLattice defects and precipitates induced in unimplanted and Sb-implanted <110> single crystal Al by single pulse irradiation with a Q-switched ruby laser were studied using ion beam analysis and electron microscopy. The absorbed laser energy during irradiation is directly measured in these studies to allow precise numerical modeling of the melt times and temperature profiles. For unimplanted Al, slip deformation gives rise to increased channeled yields throughout the analyzed depth and occurs for energies well below the melt threshold energy of 3.5 J/cm2. Slip deformation is also observed for irradiation energies above the melt threshold energy, and melting is accompanied by a discontinuous increase in the minimum channeling yield, X min- Implanted Sb (to ∼2 at.% peak concentrations) is found to impede epitaxial regrowth and result in polycrystalline Al formation for laser energies such that the melt front is believed not to penetrate through the Sb-containing region. For deeper melt depths, a metastable alloy is formed with up to 35% of the Sb located in substitutional sites. AlSb precipitate formation in the melt was not observed for room temperature irradiations; however, randomly oriented AlSb precipitates are observed for irradiation at substrate temperatures of 100 and 200 °C These measurements yield an estimated time for nucleation of AlSb precipitates in molten Al of 5 nsec < tnuc < 25 nsec.

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In-Situ Control of Wafer Charge Neutralization During High Current Ion Implants

MRS Proceedings ◽

10.1557/proc-316-633 ◽

1993 ◽

Vol 316 ◽

Author(s):

E.N. Shauly ◽

E. Koltin ◽

I. Munin ◽

Y. Avrahamov

Keyword(s):

Real Time ◽

Ion Beam ◽

High Yield ◽

Wafer Surface ◽

High Current ◽

Charge Condition ◽

Major Process ◽

Process Issue ◽

Current Monitoring

ABSTRACTIon implantation in semiconductor devices frequently leads to a substantial wafer surface charge build up. Control of this charge during high current implantation is a major process issue, as it may affect the yield and reliability of thin dielectric layers. In addition, the charge build up may affect the ion beam resulting in a non-uniform implant and a reduction in device yield. Control of a specific machine parameter, that will give the charge condition of the ion implanter will enable to neutralize the charge build up.In this study, Disk Current Monitoring (DCM) is shown to be a reliable method for monitoring the Electron Shower (ES) performance in real time. A correlation was found between DCM level and yields, and between DCM level and breakdown voltage, as well as different maintenance activities regarding me ES. A simple 5 steps method is described to achieve a reliable, real time charge monitor, to insure operation within the “High Yield Range”.

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Pulsed high current ion beam processing equipment

Surface and Coatings Technology ◽

10.1016/s0257-8972(96)03079-4 ◽

1997 ◽

Vol 90 (1-2) ◽

pp. 21-28 ◽

Cited By ~ 3

Author(s):

Sergey A. Korenev ◽

Anthony J. Perry

Keyword(s):

Ion Beam ◽

High Current ◽

Processing Equipment

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14C AMS Measurements of <100 μG Samples with a High-Current System

Radiocarbon ◽

10.1017/s0033822200018117 ◽

1997 ◽

Vol 40 (1) ◽

pp. 247-253 ◽

Cited By ~ 26

Author(s):

Karl F. Von Reden ◽

Ann P. McNichol ◽

Ann Pearson ◽

Robert J. Schneider

Keyword(s):

Current System ◽

Ion Beam ◽

Beam Current ◽

Small Sample ◽

Small Samples ◽

High Current ◽

Beam Optics ◽

Woods Hole Oceanographic Institution ◽

Factors Affecting ◽

The Past

The NOSAMS facility at Woods Hole Oceanographic Institution has started to develop and apply techniques for measuring very small samples on a standard Tandetron accelerator mass spectrometry (AMS) system with high-current hemispherical Cs sputter ion sources. Over the past year, results on samples ranging from 7 to 160 μg C showed both the feasibility of such analyses and the present limitations on reducing the size of solid carbon samples. One of the main factors affecting the AMS results is the dependence of a number of the beam optics parameters on the extracted ion beam current. The extracted currents range from 0.5 to 10 μA of 12C− for the sample sizes given above. We here discuss the setup of the AMS system and methods for reliable small-sample measurements and give the AMS-related limits to sample size and the measurement uncertainties.

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