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Brian E. Zimmerman, Jeffrey T. Cessna, Ryan P. Fitzgerald
A solution containing 68Ge in equilibrium with its daughter, 68Ga, has been standardized for the first time at the National Institute of Standards and Technology using 3 liquid scintillation- based techniques: live-timed 4pb-g anticoincidence (LTAC)
This paper describes a platform for studying the bending behavior of ultra-compliant (stiffness less than 1 N/m) atomic force microscope (AFM) cantilevers. The fundamental issue is that a cantilever does not represent an ideal design for precision force
Christopher W. Jones, John A. Kramar, Stuart Davidson, Richard Leach, Jon R. Pratt
Small masses in the 1.0 mg to 0.1 mg range were developed and calibrated at NPL with traceability to the IPK. These masses were transported to NIST at Gaithersburg and used as deadweights on the NIST electrostatic force balance, to facilitate a mass-force
Critical Dimension Atomic Force Microscopy (CD-AFM) is a primary means to measure the geometric shapes of walls and trenches on the nanometer scale in laboratories supporting the electronic industry. As the widths of commercially available CD-AFM probes
We present a quantitative method for determining the viscoelastic properties of materials with nanometer spatial resolution. The approach is based on the atomic force acoustic microscopy (AFAM) technique that involves the resonant frequencies of the AFM
Ravikiran Attota, Michael T. Stocker, Richard M. Silver, Nathanael A. Heckert, Hui Zhou, Richard J. Kasica, Lei Chen, Ronald G. Dixson, Ndubuisi G. Orji, Bryan M. Barnes, Peter Lipscomb
In this paper we present overlay measurement techniques that use small overlay targets for advanced semiconductor applications. We employ two different optical methods to measure overlay using modified conventional optical microscope platforms. They are
Andrew J. Berglund, Matthew D. McMahon, Jabez J. McClelland, James A. Liddle
We introduce a fast and robust technique for single-particle tracking with nanometer accuracy.We extract the center-of-mass of the image of a single particle with a simple, iterative algorithm that efficiently suppresses background-induced bias in a
James L. Hanssen, Shannon B. Hill, Jon Orloff, Jabez J. McClelland
We report 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
Gregory M. Rutter, Jason Crain, N Guisinger, Phillip N. First, Joseph A. Stroscio
Scanning tunneling microscopy (STM) and spectroscopy (STS) is used to study the structural and electronic properties of bilayer epitaxial graphene on SiC(0001). Topographic images reveal that graphene conforms to the SiC interface roughness and is observed
N Guisinger, Gregory M. Rutter, Jason Crain, Christian Heiliger, P First, Joseph A. Stroscio
The growth of graphene on the silicon terminated face of 6H-SiC(0001) was investigated by scanning tunneling microscopy (STM) measurements. The initial stages of ultra high vacuum (UHV) graphitization resulted in the growth of individual graphene sheets on
We present a microfabricated atomic force microscope (AFM) cantilever and associated calibration procedure that provide a path for quantitative friction measurement using a lateral force microscope. The lateral force cantilever presented is equipped with
One of the major difficulties in calibrating the lateral forces measured with optical lever Atomic Force Microscopy is in determining the lateral optical lever sensitivity. Novel cantilevers have been designed and fabricated to simplify this measurement
Gregory M. Rutter, N Guisinger, Jason Crain, Emily Jarvis, Mark D. Stiles, T Li, P First, Joseph A. Stroscio
The potential for electronics based on graphene, a single layer of sp2-bonded carbon atoms, rests on the ability to fabricate graphene into useful devices. Graphene grown epitaxially on SiC substrates offers an avenue for carbon-based electronics allowing
Philip Pong, John E. Bonevich, William F. Egelhoff Jr.
The discovery of tunneling magnetoresistance (TMR) has enhanced the magnetoresistance (MR) ratio from the giant magnetoresistance (GMR) regime of around 10% to over 400% at room temperature. A combination of magnetic tunnel junctions with high
Lawrence T. Hudson, Stephen M. Seltzer, Paul M. Bergstrom, Frank Cerra
A suite of technical performance standards is nearing completion that encompasses all the nation s security systems that screen using x-rays or gamma-rays. Specifically, these documentary standards address the aspects of imaging quality and radiation
Dianne L. Poster, John A. Small, Michael T. Postek
The National Nanotechnology Initiative (NNI) in its 2006 document, Environmental, Health, and Safety Research Needs for Engineered Nanoscale Materials (available at www.nano.gov), identifies standards and standard measurement protocols as a critical
Alessandro Troisi, J M. Beebe, Laura B. Picraux, Roger D. van Zee, D R. Stewart, M Ratner, James G. Kushmerick
Using inelastic electron tunneling spectroscopy (IETS) to measure the vibronic structure of non-equilibrium molecular transport, aided by a quantitative interpretation scheme based on non-equilibrium Greens function/density functional theory methods, we
A new method of calibrating the stiffness of atomic force microscope (AFM) cantilevers is demonstrated using a unique array of uniform microfabricated reference cantilevers. A series of force-distance curves were obtained using a commercial AFM test
Gregory M. Rutter, Jason Crain, T Li, P First, Joseph A. Stroscio
A single sheet of carbon, graphene, exhibits unexpected electronic properties that arise from quantum state symmetries, which restrict the scattering of its charge carriers. Understanding the role of defects in the transport properties of graphene is
Christopher L. Soles, Hae-Jeong Lee, B D. Vogt, Eric K. Lin, Wen-Li Wu
The structure characterization of nanoporous interlevel dielectric (ILD) thin films is challenging because of the small sample volumes and nanometer dimensions of the pores. In this chapter, we review characterization methods for porous ILD materials using
A method is presented that allows direct measurement of a wide range of spring constants of cantilevers using an indentation instrument with an integrated optical microscope. An accuracy of better than 10% can be achieved for spring constants from 0.1 N/m
We report on a fully nonequilibrium theory of scanning tunneling microscopy (STM) through resonances induced by impurity atoms adsorbed on metal surfaces. The theory takes into account the effect of tunneling current and finite bias on the system, and is
Zhandos Utegulov, B. T. Draine, Sudook A. Kim, J. M. Shaw, Ward L. Johnson
Enhancement of Brillouin light scattering (BLS) at 532 nm was observed from Rayleigh-like and Sezawa-like acoustic modes of alkaline-earth boro-aluminosilicate glass covered with periodic arrays of gold nanodisks. This enhancement is larger than that