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Elastic-property measurements of ultrathin films using atomic force acoustic microscopy

April 5, 2005

Author(s)

Malgorzata Kopycinska-Mueller, Roy H. Geiss, Jens Mueller, Donna C. Hurley

Atomic force acoustic microscopy (AFAM), an emerging technique that affords nanoscale lateral and depth resolution, was employed to measure the elastic properties of ultrathin films. In this study we measured the indentation modulus M of three nickel films

Chemical Imaging of Heterogeneous Polymeric Materials With Near-Field IR Microscopy

April 1, 2005

Author(s)

Chris A. Michaels, D B. Chase, Stephan J. Stranick

The development of techniques to probe spatial variations in chemical composition on the nanoscale continues to be an important area of research in the characterization of polymeric materials. Recent efforts have focused on the development and

Physics Laboratory: 2003-2004 Activities, Accomplishments and Recognition

February 1, 2005

Author(s)

Jonathan E. Hardis, William R. Ott

Influence of Tip Wear on Atomic Force Acoustic Microscopy Experiments

January 31, 2005

Author(s)

Malgorzata Kopycinska-Mueller, Roy H. Geiss, Paul Rice, Donna C. Hurley

Tip wear and its corresponding change in geometry is a major impediment for quantifying atomic force acoustic microscopy (AFAM). To better understand the process of tip wear and its influence on AFAM measurements of material elastic properties, we have

Development and Application of Multiple D-Layer Reference Materials for Semiconductor Analysis

January 1, 2005

Author(s)

K J. Kim, D Moon, P Chi, David S. Simons

The rapid progress in the semiconductor industry requires more precise in-depth profiling analysis of doping elements in narrower and shallower regions. Secondary ion mass spectrometry (SIMS) is the most popular technique for the depth distribution of

Polycyclic Aromatic Hydrocarbons in Flames, in Diesel Fuels, and in Diesel Emissions

January 1, 2005

Author(s)

Robert A. Fletcher, R Dobbins, Bruce A. Benner Jr, S Hoeft

Diesel fuels and emissions are composed of numerous hydrocarbon species. Combustion generated or pyrogenic polycyclic aromatic hydrocarbons (PAHs) derived from premixed and diffusion flames often consists of the most stable benzenoid PAHs. In contrast

Nanoscale Elastic-Property Mapping with Contact-Resonance-Frequency AFM

December 31, 2004

Author(s)

Donna C. Hurley, Tony B. Kos, Paul Rice

We describe dynamic atomic force microscopy (AFM) techniques to map the nanoscale elastic properties of surfaces, thin films, and nanostructures. Our approach is based on atomic force acoustic microscopy (AFAM) methods that have previously been used for

Standardization of Isotope Ratio Measurements for Doping Control

December 1, 2004

Author(s)

R M. Verkouteren

Pharmaceutical steroids are known to differ in isotopic composition from those produced naturally in the body. By measuring the 13 C/ 12C ratio of specific steroids deteched in urine, the technique of Gas Chromatography-Combustion-Isotope Ratio Mass

Maximum Pixel Spectrum: A New Tool For Detecting And Recovering Rare, Unanticipated Features From Spectrum Image Data Cubes

November 1, 2004

Author(s)

David S. Bright, Dale E. Newbury

A new software tool, the Maximum Pixel Spectrum detects rare events within a spectrum image data cube, such as that generated with electron-excited energy dispersive x-ray spectrometry (EDS) in a scanning electron microscope. The Maximum Pixel Spectrum is

Dynamic behavior of dagger-shaped atomic force microscope cantilevers

October 20, 2004

Author(s)

K Shen, Donna C. Hurley, J Turner

Experimental techniques based on the atomic force microscope (AFM) have been developed for characterizing mechanical properties at the nanoscale and applied to a variety of materials and structures. Atomic force acoustic microscopy (AFAM) is one such

Automated Analysis of Organic Particles Using Cluster SIMS

June 1, 2004

Author(s)

John G. Gillen, Cynthia J. Zeissler, Christine M. Mahoney, Abigail P. Lindstrom, Robert A. Fletcher, P Chi, Jennifer R. Verkouteren, David S. Bright, R Lareau, M Boldman

Cluster primary ion bombardment combined with secondary ion imaging is used in an ion microscope secondary ion mass spectrometer for the spatially resolved analysis of organic particles on various surfaces. Compared to the use of monoatomic primary ion

Depth Profiling of 4-Acetamindophenol-Doped Poly(lactic acid) Films Using Cluster Secondary Ion Mass Spectrometry

June 1, 2004

Author(s)

Christine M. Mahoney, S V. Roberson, John G. Gillen

The feasibility of cluster Secondary Ion Mass Spectrometry (SIMS) for depth profiling of drug delivery systems is explored. Behaviors of various biodegradable polymer films under dynamic SF 5 + primary ion bombardment was investigated including several

Dynamic SIMS Utilizing SF 5 + Polyatomic Primary Ion Beams for Drug Delivery Applications

June 1, 2004

Author(s)

Christine M. Mahoney, S V. Roberson, John G. Gillen

The behavior of various biodegradable polymer films (e.g. polylactic acid, polyglycolic acid and polycaprolactone) as well as some model drugs (theophylline and 4-acetamidophenol) under dynamic SF 5 + primary ion bombardment is explored. A series of

Relative humidity effects on the determination of elastic properties with atomic force acoustic microscopy

March 1, 2004

Author(s)

Donna C. Hurley, J Turner

We have investigated how ambient humidity can affect quantitative measurements of elastic properties on the nanoscale. Using an emerging technique called atomic force acoustic microscopy (AFAM), two samples were examined: a thin film of fluorosilicate

Membrane Surface Dynamics of DNA-Threaded Nanopores Revealed by Simultaneous Single-Molecule Optical and Ensemble Electrical Recording

February 3, 2004

Author(s)

E L. Chandler, A L. Smith, Lisa K. Burden, John J. Kasianowicz, D L. Burden

We demonstrate a method for simultaneous real-time electrical and single-molecule optical recordings of the interactions between single-stranded DNA and nanoscopic pores in planar lipid membranes. Electrophysiological techniques are used to measure the

Semiconductor Nanocrystal Probes for Human Metaphase Chromosomes

February 1, 2004

Author(s)

Yan Xiao, Peter E. Barker

Novel inorganic fluorophores called semiconductor nanocrystals have recently been incorporated into protein, antibody and microbead oligonucleotide detection methods where previously, organic dyes were universally employed. To improve quantitation of

Nanometrology - FY 2003 Program and Selected Accomplishments

December 15, 2003

Author(s)

Clare M. Allocca, Stephen W. Freiman

The emphasis on nanotechnology around the world is leading to the development and commercialization of unique products based upon significantly smaller devices and material ensembles. Materials at the nanoscale in three dimensions (NEMS, MEMS), two

Value Assignment and Uncertainty Estimation of Selected Light Stable Isotope Reference Materials: RMs 8543-8545, RMs 8562-8564, and RM 8566

December 1, 2003

Author(s)

R M. Verkouteren, D Klinedinst

We report the technical basis for value assignments of several carbon and oxygen stable isotope reference materials distributed by NIST and the International Atomic Energy Agency (IAEA), and make recommendations regarding laboratory practices and future

Ferroelectric Phase Transitions in Nano-Scale Chemically Ordered PbSc 0.5 Nb 0.5 O 3 Using a First-Principles Model Hamiltonian

July 1, 2003

Author(s)

U Waghmare, Eric J. Cockayne, Benjamin P. Burton

fects of chemical order, disorder, short range order, and anti-phase boundaries on phase transitions and dielectric properties of PBSc 1/2Nb 1/2O 3 are studied through molecular dynamics simulations of a FP model. Simulations of large systems are required

Tools and Procedures for Quantitative Microbeam Isotope Ratio Imaging by Secondary Ion Mass Spectrometry

July 1, 2003

Author(s)

John G. Gillen, David S. Bright

In this work we demonstrate the use of secondary ion mass spectrometry (SIMS) combined with the Lispix image processing program (Bright 1995) to generate quantitative isotope ratio images from a test sample of a calcium-aluminum rich inclusion (CAI) from

Isotopic Metrology of Carbon Dioxide. I. Interlaboratory Comparison and Empirical Modeling of Inlet Equilibration Time, Inlet Pressure, and Ion Source Conductance

June 1, 2003

Author(s)

R M. Verkouteren, C E. Allison, S A. Studley, K J. Leckrone

We report a pilot study of high-precision differential isotopic ratio measurements made on replicate samples of pure carbon dioxide using three instruments of identical manufacture. Measurement protocols were designed to explore the effects of sample size

Isotopic Metrology of Carbon Dioxide. II. Effects of Ion Source Materials, Conductance Emission, and Accelerating Voltage on Dual-Inlet Cross Contamination

June 1, 2003

Author(s)

R M. Verkouteren, S Assonov, D Klinedinst, W Brand

We report high-precision isotope carbon dioxide measurements, made before and after ion source modification to gas isotope ratio mass spectrometry (IRMS) instruments. Measurement protocols were designed to explore the effects of ion surce material

Virtual Environment for Manipulating Microscopic Particles with Optical Tweezer

June 1, 2003

Author(s)

Yong-Gu Lee, Kevin W. Lyons, Thomas W. LeBrun

In this paper, we use virtual reality techniques to define an intuitive interface to a nanoscale manipulation device. This device utilizes optical methods to focus laser light to trap and reposition nano-to-microscopic particles. The underlying physics are

Implications of Emerging Micro and Nanotechnology

April 1, 2003

Author(s)

S Brueck, S Picraux, J Belk, Robert Celotta, W Holton, S Janson, W Kuo, D Nagel, P Penz, A Pisano, R Smith, P Stang, G Sutton, W Tolles, R Trew, M. Young

Nist-Led International Collaboration Results in Improved Measurement Technology for Light Stable Isotopes Relevant to Climate Change Research

March 1, 2003

Author(s)

R M. Verkouteren

Two manuscripts recently have been accepted in RapidCommunications in Mass Spectrometry that detail aninternational collaboration to identify, understand at afundamental level, and correct measurement biasesmanifested in gas isotope ratio mass