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Search Publications

NIST Authors in Bold

Displaying 26 - 50 of 3310

Ion-Molecule Reactions and Ion Kinetics in DC Townsend Discharges in Dielectric Gases

January 1, 1999
Author(s)
MVVS. Rao, James K. Olthoff
… and kinetic energies of ions are determined by ion-molecule collisions experienced by ions as they are … as charge-exchange collisions, collisional detachment, and ion conversion, we have measured the kinetic-energy … measurements, and the effective cross sections for the ion-molecule reactions, in some cases, may be calculated. The …

Direct Imaging of Static and Dynamic Ion Cloud Distributions in an Electron Beam Ion Trap

February 1, 2000
Author(s)
James V. Porto
… directly image highly charged ions within an electron beam ion trap (EBIT). Using an intensified CCD camera, we have the capability to measure both static and dynamic ion cloud distributions. The technique provides information … by other methods. Static images can be used to determine ion temperatures and the degree of overlap between the …

Spectroscopic Ellipsometry: In Situ Monitor and Control of III-V Semiconductors Grown by Molecular Beam Epitaxy

February 19, 1999
Author(s)
Donald A. Gajewski, Jonathan E. Guyer, Joseph G. Pellegrino
… monitor and control the physical properties of thin film III-V semiconductors, in situ and in real time during film … semiconductors, spectroscopic ellipsometry, thin film III-V semiconductors … Spectroscopic Ellipsometry: In Situ Monitor and Control of III-V Semiconductors Grown by Molecular Beam Epitaxy …

Charge States of y Ions in the Collision-Induced Dissociation of Doubly Charged Tryptic Peptide Ions

February 25, 2011
Author(s)
Pedatsur Neta, Stephen E. Stein
… relative intensities of charge states of product y- and b-ions depend on the final location of that proton. This study … distributions for dissociation of doubly charged peptide ions, using a large reference library of peptide ion fragmentation generated from ion-trap CID of peptide ions from tryptic digests. Trends in relative intensities of …

A Miniature EBIT with Ion Extraction for Isolating Highly Charged Ions

May 28, 2015
Author(s)
Shannon Hoogerheide, Joseph Tan
… development of a room-temperature miniature electron beam ion trap (EBIT) for efficient production of charge states … and electric potential necessary for the production of ions in the EBIT. In addition to radial access for in-EBIT … select a single charge state to be isolated in a secondary ion trap for further study. One goal is the production of …

Graphene, Ge/III-V, Nanowires and Emerging Materials for Post-CMOS Applications 3 -and- Tutorials in Nanotechnology: Dielectrics in Nanosystems

April 21, 2011
Author(s)
Alamgir Karim, Veena Misra, G. Srinivasan, Yaw S. Obeng, S De Gendt
… Behavior of Graphene and Graphene Based Devices; (f) Ge & III-V devices for CMOS mobility enhancement; (g) III.V Heterostructures on Si substrates; (h) Nano-wires … and modeling; (i) Simulation of devices based on Ge, III-V, nano-wires and Graphene; (j) Nanotechnology …

The Mobilities of NO + (CH 3 CN)n Cluster Ions (n=0-3) Drifting in helium-Acetonitrile Mixtures

December 1, 1996
Author(s)
J A. de Gouw, L N. Ding, M Krishnamurthy, H S. Lee, E B. Anthony, V M. Bierbaum, S R. Leone
… The mobilities of NO+(CH 3 CN) n cluster ions (N=0-3) drifting in helium and in mixtures of helium and … of the geometric cross sections of the different cluster ions. The rate constants for the various cluster formation … 2 and NO + (CH 3 CN) 3 , the drift velocities for these ions are found to be strongly dependent on the acetonitrile …

Scanning Ion Microscopy with Low Energy Lithium Ions

July 1, 2014
Author(s)
Kevin A. Twedt, Lei Chen, Jabez J. McClelland
… Using an ion source based on photoionization of laser-cooled lithium atoms, we have developed a scanning ion microscope with probe sizes of a few tens of nanometers … in ion microscopy when detecting backscattered ions, due to a decreased interaction volume and the potential …

X-Ray Spectroscopy of Trapped Ions With a Microcalorimeter on the NIST Electron Beam Ion Trap

December 1, 2002
Author(s)
E Takacs, John D. Gillaspy, L P. Ratliff, K Makonyi, J M. Laming, E Silver, H. Schnopper, M Barbera, J. Beeman, E. E. Haller, N. Madden
… The electron beam ion trap (EBIT) was invented about 15 years ago. Judging from … and study the structure and interactions of highly charged ions. Today, EBITs exist in several different laboratories … in a variety of fields of research where multiply charged ions relevant. Recent astrophysical missions by NASA and …

Performance of a C 60 + Ion Source on a Dynamic SIMS Instrument

July 1, 2006
Author(s)
Albert J. Fahey, John G. Gillen, P Chi, Christine M. Mahoney
… An IonOptika [1] C60+ ion source has been fitted onto a CAMECA [1] ims-4f. Stable ion beams of C60+ and C602+ have been obtained with typical … able to be focussed into a spot size of ~1 ?m and scanning ion images acquired. We have performed analyses to … Buckministerfullerene, cluster ion beams, ion source, SIMS ion source …

Noninvasive monitoring of ion current and ion energy during plasma processing

July 15, 2008
Author(s)
Mark A. Sobolewski
… technique has been developed for noninvasive monitoring of ion energy and ion current in plasma reactors. The technique relies on … electrical waveforms, the technique determines the total ion current, the plasma potential and sheath voltage … ion current, ion energy, electrical measurements, inductively …

Cold atomic beam ion source for focused ion beam applications

July 23, 2013
Author(s)
Brenton J. Knuffman, Adam V. Steele, Jabez J. McClelland
… We report measurements and modeling performed on an ion source based on ionization of a laser-cooled atomic beam. … for use in next-generation, high-resolution focused ion beam (FIB) systems. Our measurements of total ion current as a function of ionization conditions support a …

Inter-ion Coulomb interactions in a Magneto-Optical Trap Ion Source

May 19, 2011
Author(s)
Jabez J. McClelland, Brenton J. Knuffman, Adam V. Steele
… We have investigated the role played by inter-ion Coulomb interactions in a magneto-optical trap ion source (MOTIS). Using a Monte Carlo simulation accounting … MOTIS, ion beams, coulomb replusion … Inter-ion Coulomb interactions in a Magneto-Optical Trap Ion Source …

Ion-Molecule Reactions and Ion Energies in CF 4 Discharges

December 1, 1999
Author(s)
B. Peko, I. V. Dyakov, R. Champion, MVVS. Rao, James K. Olthoff
… E/N values ranging from 4 x 10 -18 V m 2 (4 to 25 kTd). Ion energy and ion intensity data for the Townsend discharges are analyzed … cross sections, dissociative charge transfer, ion energies, ion molecule reactions, Townsend discharge … Ion-Molecule Reactions and Ion Energies in CF 4 Discharges …

High-brightness Cs focused ion beam from a cold-atomic-beam ion source

May 2, 2017
Author(s)
Adam V. Steele, Andrew Schwarzkopf, Jabez J. McClelland, Brenton Knuffman
… of focal spot size and brightness in a focused ion beam system utilizing a laser-cooled atomic beam source … than the highest brightness observed in a Ga liquid metal ion source. The behavior of brightness as a function of beam … as next-generation circuit edit and nanoscale secondary ion mass spectrometry. …

Magneto-Optical-Trap-Based, High Brightness Ion Source for Use as a Nanoscale Probe

August 21, 2008
Author(s)
James L. Hanssen, Shannon B. Hill, Jon Orloff, Jabez J. McClelland
… on the demonstration of a low emittance, high brightness ion source based on magneto-optically trapped neutral atoms. Our source has ion optical properties comparable to or better than those of the commonly used liquid metal ion source. In addition, it has several advantages that offer …

Ion Solvation in Water Acetonitrile Mixtures

January 1, 2001
Author(s)
Raymond D. Mountain
… The results of a preliminary molecular dynamics study of ion (NA+ and Cl-) solvation and association in water, … is expected to be an important factor governing ion solvation and association. Results for ions in pure water … than the temperature in determining the degree of ion association. Preliminary results for the mixtures are …

Micro-fabricated stylus ion trap

August 7, 2013
Author(s)
Kyle S. McKay, Christian L. Arrington, Ehren D. Baca, Jonathan J. Coleman, Yves Colombe, Patrick Finnegan, Dustin A. Hite, Andrew E. Hollowell, Robert Jordens, John D. Jost, Dietrich G. Leibfried, Adam M. Rowen, Ulrich J. Warring, David J. Wineland, David P. Pappas, Andrew C. Wilson
… stylus Paul trap was designed to confine a single atomic ion for use as a sensor to probe the electric-field noise of … with the UV-LIGA technique to reduce the distance of the ion from the surface of interest. We detail the fabrication … environment. After cooling a motional mode of the ion at 4 MHz close to its ground state (n = 0.34 � 0.07), the …

Advances in source technology for focused ion beam instruments

April 1, 2014
Author(s)
Noel Smith, John Notte, Adam V. Steele
… Owing to the development of new ion source technology, users of focused ion beams (FIBs) have an increasingly wide array of uniquely … capable platforms to choose from. Specifically, the new ion sources are able to offer superior performance in several … ion sources, focused ion beams, inductively coupled plasma, …

Motional Squeezing for Trapped Ion Transport and Separation

August 20, 2021
Author(s)
Robert Sutherland, Shaun Burd, Daniel Slichter, Stephen Libby, Dietrich Leibfried
… Transport, separation, and merging of trapped ion crystals are essential operations for most large-scale … framework, we develop a new, general protocol for trapped ion transport, separation, and merging. We show that motional squeezing can prepare an ion wave packet to enable transfer from the ground state of …

Negative Cesium Sputter Ion Source for Generating Cluster Primary Ion Beams for Secondary Ion Mass Spectrometry Analysis

April 1, 2001
Author(s)
John G. Gillen, R L. King, B Freibaum, R Lareau, J Bennett, F Chmara
… The use of a cluster (or polyatomic) primary ion projectile for organic SIMS has been demonstrated to … use of a commercially available negative cesium sputter ion as a means of generating cluster ion beams on our Cameca IMS 4F and 6F magnetic sector SIMS … cluster beam, depth profiling, organic secondary ion mass spectrometry …

Helium Ion Microscopy: A New Technique for Semiconductor Metrology and Nanotechnology

January 1, 2007
Author(s)
Michael T. Postek, Andras Vladar, John A. Kramar, L A. Stern, John Notte, Sean McVey
… The Helium Ion Microscope (HIM) offers a new, potentially disruptive … the helium ions, it is theoretically possible to focus the ion beam into a smaller probe size relative to that of an … achievable. In contrast to the SEM, when the helium ion beam interacts with the sample, it generates …
Displaying 26 - 50 of 3310
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