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Displaying 1676 - 1700 of 2608

Collaborative Augmented Reality for Better Standards

July 1, 2007
Author(s)
Matthew L. Aronoff, John V. Messina
Concurrent engineering depends on clear communication between all members of the development process. As that communication becomes more and more complex, the quality of the standards used to move and understand that information likewise becomes more and

The Polarizability of Helium and Gas Metrology

June 22, 2007
Author(s)
James W. Schmidt, R Gavioso, E May, Michael R. Moldover
Using a quasi-spherical, microwave cavity resonator, we measured the refractive index of helium to deduce its molar polarizability A ε in the limit of zero density. We obtained (A ε,meas - A ε,theory)/A ε = (-1.8plus or minus} 8.4)× 10 -6, where the

Extending the Limits of Image-Based Optical Metrology

June 20, 2007
Author(s)
Richard M. Silver, Bryan M. Barnes, Ravikiran Attota, Jay S. Jun, Michael T. Stocker, Egon Marx, Heather J. Patrick
We have developed a set of techniques, referred to as scatterfield microscopy, in which the illumination is engineered in combination with appropriately designed metrology targets. Previously we reported results from samples with sub-50 nm sized features

Direct Electrostatic Calibration of Hybrid Sensors for Small Force Measurement

June 4, 2007
Author(s)
Koo-Hyun Chung, Gordon A. Shaw, Jon R. Pratt
The measurement of forces from piconewtons to millinewtons is an area of interest from both an applied and pure research standpoint, however creating a link between small forces and the International System of Units (SI) has been difficult. In this work, a

Measurement of Weld Toughness - Crack Tip Opening Angle Criterion

June 1, 2007
Author(s)
Philippe P. Darcis, Joseph D. McColskey, Christopher N. McCowan, Thomas A. Siewert
The stable tearing behavior of X100 pipeline steel through a girth weld section was investigated using a modified double cantilever beam specimens. A test technique for direct measurement of the steady state crack tip opening angle (CTOA) criterion was

Calibrating Laser Vacuum Wavelength With a GPS-Based Optical Frequency Comb

May 15, 2007
Author(s)
Jack A. Stone Jr., Liang Lu, Patrick F. Egan
The Global Positioning System (GPS) can deliver an exceptionally accurate frequency standard to any point in the world. When we use the GPS signal to control an optical frequency comb, the comb+GPS system provides laser light with well-known frequencies

Capacitors and Electromagnetic Resonators for Gas Metrology

May 1, 2007
Author(s)
Michael R. Moldover, James W. Schmidt
Gas-filled capacitors are being used as primary thermometers and they show promise as primary pressure standards and for measuring the Boltzmann constant. With these metrological applications in mind, we discuss the advantages and disadvantages of audio

Surface Topography Analysis for a Feasibility Assessment of a National Ballistics Imaging Database

May 1, 2007
Author(s)
Theodore V. Vorburger, James H. Yen, B Bachrach, Thomas Brian Renegar, Li Ma, Hyug-Gyo Rhee, Xiaoyu Alan Zheng, Jun-Feng Song, Charles D. Foreman
This document reports on a study to determine the feasibility and utility of a national ballistics database of casing and bullet images. The purpose of such a proposed database would be to provide a reference collection of ballistic images against which

Traceable Micro-Force Sensor for Instrumented Indentation Calibration

April 10, 2007
Author(s)
Douglas T. Smith, Gordon A. Shaw, R M. Seugling, D Xiang, Jon R. Pratt
Instrumented indentation testing (IIT), commonly referred to as nanoindentation when small forces are used, is a popular technique for determining the mechanical properties of small volumes of material. Sample preparation is relatively easy, usually

A Piezoresistive Cantilever Force Sensor for Direct AFM Force Calibration

April 8, 2007
Author(s)
Jon R. Pratt, John A. Kramar, Gordon A. Shaw, Douglas T. Smith, John M. Moreland
We describe the design, fabrication, and calibration testing of a new piezoresistive cantilever force sensor suitable for the force calibration of atomic force microscopes in a range between tens of nanonewtons to hundreds of micronewtons. The sensor is

TEM Calibration Methods for Critical Dimension Standards

April 5, 2007
Author(s)
Ndubuisi G. Orji, Ronald G. Dixson, B Bunday, M R. Bishop, Michael W. Cresswell, J Allgair
One of the key challenges in critical dimension (CD) metrology is finding suitable calibration standards. Over the last few years there has been some interest in using features measured with transmission electron microscope (TEM) as primary standards for

Neutron Collimation With Microchannel Plates: Calibration of Existing Technology and Near

April 1, 2007
Author(s)
A S. Tremsin, Daniel S. Hussey, David L. Jacobson, Muhammad D. Arif, Robert Gregory Downing, W B. Feller, David F. Mildner
A new type of high performance and compact neutron collimator can be manufactured from Gd- or B-doped microchannel plates (MCPs). Structures only a few mm thick have very narrow rocking curves and high out-of-angle rejection ratios, as observed previously

Application of Carbon Nanotube Probes in a Critical Dimension Atomic Force Microscope

March 1, 2007
Author(s)
B C. Park, J Choi, S J. Ahn, D H. Kim, L Joon, Ronald G. Dixson, Ndubuisi George Orji, Joseph Fu, Theodore V. Vorburger
The ever decreasing size of semiconductor features demands the advancement of critical dimension atomic force microscope (CD-AFM) technology, for which the fabrication and use of more ideal probes like carbon nanotubes (CNT) is of considerable interest

The Coming of Age of Tilt CD-SEM

March 1, 2007
Author(s)
B Bunday, J Allgair, E Solecky, C Archie, Ndubuisi George Orji
The need for 3D metrology is becoming more urgent to address critical gaps in metrology for both lithographic and etch processes. Current generation lithographic processing (ArF source, where lambda=193 nm) sometimes results in photoresist lines with re

Zero-Order Imaging of Device-Sized Overlay Targets Using Scatterfield Microscopy

March 1, 2007
Author(s)
Bryan M. Barnes, Lowell P. Howard, P Lipscomb, Richard M. Silver
Patterns of lines and trenches with nominal linewidths of 50 nm have been proposed for use as an overlay target appropriate for placement inside the patterned wafer die. The NIST Scatterfield Targets feature groupings of eight lines and/or trenches which

Accuracy in Optical Image Modeling

February 26, 2007
Author(s)
James E. Potzick, Egon Marx, M P. Davidson
Wafer exposure process simulation and optical photomask feature metrology both rely on optical image modeling for accurate results. The best way to gauge the accuracy of an imaging model is to compare the model results with an actual image. Modeling
Displaying 1676 - 1700 of 2608