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This report summarizes the research and measurement science carried out during calendar year 2001 in the NIST Physics Laboratory. The Laboratory supports U.S. industry, government, and the scientific community by providing measurement services and research
N Jin, A T. Rice, P R. Berger, P E. Thompson, C Rivas, R Lake, S Sudirgo, J J. Kempisty, B Curanovic, S L. Rommel, K D. Hirschman, S K. Kurinec, P Chi, David S. Simons, S.J. Chung
Si/SiGe resonant interband tunnel diodes (RITD) employing delta-doping spikes that demonstrate negative differential resistance (NDR) at room temperature are presented. Efforts have focused on improving the tunnel diode peak-to-valley current ratio (PVCR)
At the National Institute of Standards and Technology (NIST) we have a capability for conducting cluster SIMS experiments on both our ion microscope and TOF-SIMS instruments. This paper will review our recent work on cluster ion source development
Eric S. Windsor, R Carlton, John G. Gillen, Scott A. Wight, David S. Bright
Copper oxide has been detected in the copper containing alloys of Standard Reference Material (SRM) 482. This occurrence is significant because it represents heterogeneity within a standard reference material that was certified to be homogeneous on a
Youngjoon Han, Jeongjae Ryu, Andreas Schiffer, Jason Killgore, Seungbum Hong
Electrical properties of hydroxyapatite (HAp), the main constituent of the mineralized portion of the cortical bone, and a key variable in Wolff's law, remain an enigma up to this date. In order to make a comparison between the contribution of the
K R. Lemire, D T. Allen, George A. Klouda, C. W. Lewis
Radiocarbon analyses of fine particulate matter samples collected during the summer of 2000 in southeast Texas indicate that a substantial fraction of the aerosol carbon at an urban/suburban site (27-73%) and at a rural, forested site (45-78%) was modern
Jennifer R. Verkouteren, Eric S. Windsor, Joseph M. Conny, R L. Perkins, J T. Ennis
A simple ashing procedure is described that converts kaolinite to amorphous metakaolinite while retaining the diffraction intensity of chrysotile. This ashing procedure removes the XRD pattern overlap between kaolinite and chrysotile that can interfere
John D. Gillaspy, L P. Ratliff, J R. Roberts, E Takacs
Assembled here are the publications of NIST Electron Beam Ion Trap (EBIT) project, from its inception through the end of 2001. They are grouped thematically, as indicated in the table of contents. In order to address some of the most frequently asked
George A. Klouda, C. W. Lewis, D C. Stiles, J L. Marolf, W D. Ellenson, W A. Lonneman
An objective of the 1997 Southern California Ozone Study (SCOS97) was to provide an up-to-date assessment of the importance of biogenic emissions for tropospheric ozone production in the South Coast Air Basin. To this end ambient air samples were collected
Terrence J. Jach, S M. Durbin, A S. Bakulin, David S. Bright, C B. Stagarescu, G Srajer, D. Haskel, J Pedulla
Modern technology permits us to fabricate Kirkpatrick-Baez (KB) multilayer optics with performance close to the theoretical limit. We have constructed a KB field-imaging microscope which operates in the x-ray energy range 6-10 keV with a field of view of
This work describes the comparison of experimental measurements of electron beam spread in the environmental scanning electron microscope with model predictions. Beam spreading is the result of primary electrons being scattered out of the focused beam by
J P. McKinley, Cynthia J. Zeissler, J M. Zachara, R J. Serne, Richard M. Lindstrom, H T. Schaef, R D. Orr
sium-137 and other contaminants have leaked from many of the single-shell storage tanks at the Hanford Site in southeastern Washington. The leakage was into sandy unconsolidated sediments consisting largely of quartz, plagioclase, micas, smectite, and
Eric S. Windsor, R Carlton, Scott A. Wight, C Lyman
The National Institute of Standards and Technology's (NIST) Standard Reference Material (SRM) 482 was issued by The National Bureau of Standards (NBS) in 1969 and has been continuously available to the public for over 30 years [1]. The standard consists of
Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) is often considered synonymous with SIMS in the static limit where the ion fluence on the sample surface is so low that damage is negligible. For this same reason its use in measuring isotopic
Cynthia J. Zeissler, Richard M. Lindstrom, J P. McKinley
We have been exploring ways to evaluate the activity of radioactive particles that have been detected by phosphor plate digital autoradiography based on photostimulated luminescence (PSL). A PSL system with 25υ pixel digitization has been applied to
E Fuoco, J Greg Gillen, M Wijesundara, William E. Wallace, L Hanley
In this paper examine the mechanism of secondary ion yield enhancements previously observed for polyatomic projectiles by measuring the weight loss, volume loss, and surface composition of poly(methylmethacrylate) (PMMA) films sputtered by keV SF 5 + and
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 increase the yield of characteristic molecular secondary ions, more efficiently desorb higher molecular weight species and reduce the accumulation of
A two-part review of research concerning block copolymer thin films is presented. The first section summarizes experimental and theoretical studies of the fundamental physics of these systems, concentrating upon the forces that govern film morphology. The
Ryna B. Marinenko, J T. Armstrong, Debra L. Kaiser, Joseph J. Ritter, Peter K. Schenck, C P. Bouldin, J Blendell, Igor Levin
Barium strontium titanate (BST) thin films of varying composition and thickness (5nm to 400nm) on (100)Si or Pt/(100)Si substrates were measured using an electron microprobe analyzer with wavelength dispersive x-ray spectrometers. Most of the films were
John G. Gillen, S V. Roberson, Albert J. Fahey, Marlon L. Walker, J Bennett, R Lareau
We are evaluating the use of polyatomic and cluster primary ion beams for characterization of semiconductor materials by secondary ion mass spectrometry using both magnetic sector and time-of-flight SIMS instruments. Primary ion beams of SF 5+, C 8- and
This article reviews some of the fundamental properties of highly charged ions, the methods of producing them (with particular emphasis on table-top devices), and their use as a tool for both basic science and applied technology. Topics discussed include
David S. Simons, P Chi, S L. Rommel, T E. Dillon, K D. Hobart, P E. Thompson, P R. Berger
Si interband tunnel diodes have been successfully fabricated by molecular beam epitaxy and room temperature peak-to-valley current ratios of 1.7 have been achieved. The diodes consist of opposing n- and p-type δ-doped injectors separated by an intrinsic Si
Ryna B. Marinenko, S V. Roberson, J S. Small, Barbara B. Thorne, Douglas H. Blackburn, D Kauffman, Stefan D. Leigh
The production and characterization of NBS K-411 glass microspheres in the 3-40 um range for certification as a NIST Standard Reference Material (SRM) are described. EDS quantitative analysis and heterogeneity evaluations of the microspheres were made with