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Dimensional measurements of importance to microlithography include feature sizes and feature placement on photomasks and wafers, overlay eccentricities, defect
Progress in the development of a cryogenic catheter to treat heart arrhythmia is discussed. This system uses a mixed-gas Joule-Thomson refrigerator to cool the
We developed a noninvasive x-ray technique to monitor the solidification of single-crystal castings. X-ray energies in the 150 keV to 320 keV range have
The U.S. Federal Government has a strong role in metrology R&D in the U.S because of its importance to the nation's economy and the Constitutional authority
We measure the electrical parameters of commercial lumped-element impedance standards manufactured for the calibration of on-wafer probing systems. The standard
This paper presents a new method that accurately determines the characteristic impedance of planar transmission lines printed on lossy dielectrics even when
This paper investigates the one-dimensional metal-insulator-semiconductor transmission line. It develops closed-form expressions for equivalent-circuit
Web sites are developed by a wide variety of companies from small one or two person operations to large corportions with entire teams and departments devoted to
Leonard E. Gebase, Mary C. Brady, Alden A. Dima, Lynne S. Rosenthal
A well-established approach to conformance testing is to treat the implementation being tested as a black box. With this approach, a reference implementation is
James P. Randa, Dave K. Walker, Lawrence P. Dunleavy, Robert L. Billinger, John Rice
A set of wafer probeable diode noise source transfer standards are characterized using on-wafer noise temperature methods developed recently at the National
Despite their many advantageous characteristics and extensive use, mixtures of methyl methacrylate monomers (MMA) and poly methyl methacrylate powders have some
Several lumped-element calibrations have been proposed for four-sampler vector network analyzers. This paper offers the first assessment of their accuracy in
R Deslattes, Ernest G. Kessler, Paul Indelicato, E Lindroth
In this brief report we describe some of the background for our continuing efforts toward a new comprehensive data base for x-ray transitions, and indicate the
Michael A. Lewis, T Kuriyama, J Xiao, Ray Radebaugh
This paper gives results of the cooling performance of a double-inlet pulse tube refrigerator using various redenerators. The same pulse tube was used for all
An ultrasonic transit time flowmeter was tested over Reynolds numbers from 1000 to 100,000 in a calibration facility that generates gas flows with controlled
Two novel acoustic resonators have been developed, one for measuring the viscosity and a second for measuring the Prandtl number of gases. For viscosity
Our laboratory has developed an automated apparatus for measuring the sound speed in hazardous gases such as those used in processing semiconductors. The sound
A field investigation of tape-bonded seams of EPDM (ethylene propylene diene terpolymer) roof membranes is described. Since the early 1990s the use of tape
Ronald G. Dixson, R Koning, Theodore V. Vorburger, Joseph Fu, V W. Tsai
Because atomic force microscopes (AFMs) are capable of generating three dimensional images with nanometer level resolution, these instruments are being
In scanned probe microscopy, it is necessary to know the tip's geometry in order to correct image distortions due to its finite size. Heretofore, methods have
J Allgair, C Archie, W Banke, H Bogardus, J Griffith, H Marchman, Michael T. Postek, L Saraf, J Schlesinger, B Singh, N. Sullivan, L Trimble, Andras Vladar, A Yanof
The stringent critical dimension (CD) control requirements in cutting edge device facilities have placed significant demands on metrologists and upon the tools
A new method is presented to determine the time-base errors of sampling instruments. The method does not require a model for the time-base error and, thus
Accurate measurement of high voltage (hv) impulse waveforms is of critical importance in the testing of hv apparatus and for fundamental insulation studies
The adhesive strength of a composite resin to dentin is greatly influenced by the degree of cure of the bonding agent. Flouorescent probes have often been used
William F. Egelhoff Jr., P J. Chen, Cedric J. Powell, D Parks, Robert McMichael, J Judy, D Martien, A. E. Berkowitz, J M. Daughton
The current generation of giant magnetoresistance (GMR) spin valves exhibits performance characteristics which are not quite as good as desired for ultrahigh