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In scanned probe microscopy the image is a combination of information from the sample and the tip. In order to reconstruct the true surface geometry, it is necessary to know the actual tip shape. It has been proposed that this shape may be reconstructed
Wave-front or surface errors may be divided into rotationally symmetric and nonrotationally symmetric terms. It is shown that if either the test part or the reference surface in an interferometric test is rotated to N equally spaced positions about the
A simple instrument for automatically controlling the deposition rate of an electronbeam evaporator is described. The design incorporates a commercially available, microprocessor based, Proportional-Integral-Differential (PID) process controller which
E W. Paul, Christopher J. Evans, A Mangamelli, Michael L. McGlauflin, Robert S. Polvani
A hypothesis is proposed that ascribes chemical wear of diamond tools to the presence of unpaired d electrons in the sample being machined. This hypothesis is used to explain a range of results for metals, alloys, and other materials including electroless
The development and application of digital imaging technology has been one of the major advancements in scanning electron microscopy (SEM) during the past several years. This digital revolution has been brought about by significant progress in
Zeina J. Kubarych, S Milosevic, A Allegrini, J Huennekens, R K. Namiotka
We report experimental rate coefficients for the energy-pooling collisions Cs(6P/sub 1/2/)+Cs(6P/sub 1/2/) to Cs(6S/sub 1/2/)+Cs(nl/sub J''/) and Cs(6P/sub 3/2/)+Cs(6P/sub 3/2/) to Cs(6S/sub 1/2/)+Cs(nl/sub J''/) where nl/sub J''/=7P/sub 1/2/, 7P/sub 3/2/
Lowell P. Howard, Fredric Scire, Jack A. Stone Jr.
A description of a Fabry-Perot interferometer for measuring small displacements is given. The instruments consists of a fiber-optic-coupled actuator and mirror guiding mechanisms, a tunable diode laser for tracking the changes in cavity length and a
V W. Tsai, Theodore V. Vorburger, P Sullivan, Ronald G. Dixson, Richard M. Silver, Edwin R. Williams, J Schneir
The decreasing feature dimensions required in the semiconductor manufacturing industry are placing ever increasing demands upon metrology instruments. Atomic force microscopes (AFMs), which can have 1 nm lateral resolution and sub-angstrom vertical
An equation for an unknown surface field that represents scattering by a rough patch on a flat dielectric surface is presented. The geometrical considerations for this particular problem are discussed, especially in relation to a surface divergence factor.
During the 1996 CMSC conference, undoubtedly one of the hottest topics was how to achieve traceability for the laser tracker. This paper reviews the concepts of traceability and measurement uncertainty from NIST''s perspective, and explain how these topics
The National Institute of Standards and Technology is developing a simple one-dimension certified pitch standard (or scale) covering the range 1 um to 10 mm, intended for the calibration of microscope magnification and dimensional metrology instrument
Jack A. Stone Jr., Lowell P. Howard, Alois Stejskal, M Stephens, C Oates, L Hollberg
Diode lasers have several unique capabilities for length-measurement applications, arising from properties of the diodes that are much different from those of the venerable helium-neon laser presently used for most interferometric measurements. For example
Richard M. Silver, Amy Singer, L Carroll, S Berg-cross, James E. Potzick
Many of the significant challenges in making accurate overlay registration measurements are discussed. An understanding of the causes of the errors affecting these measurements is a prerequisite to improving accuracy and also for the design of standard
T Mcwaid, J Schneir, John S. Villarrubia, Ronald G. Dixson, V W. Tsai
Accurate metrology using atomic force microscopy (AFM) requires accurate control of the tip position, an estimate of the tip geometry, and an understanding of the tip-surface interaction forces. We describe recent progress at NIST towards accurate AFM
The standard interpretation of quantum mechanics is revised to conform to the relativistic theory based on the many-amplitudes formalism for the N-particle system. The wave function acquires a significance closer to that of the electromagnetic field, with
Over the years many techniques have been developed for accurate measurement of part features without reference to an externally calibrated artifact. This paper presents a partial survey of such methods for dimensional metrology, their ranges of application
The technique described here, utilizing the sharpness concept, is facilitated by the use of the FFT techniques to analyze the electron micrograph to obtain the evaluation. This is not the first application of Fourier techniques to SEM images, but it is the
Jun-Feng Song, Samuel R. Low III, David J. Pitchure, Theodore V. Vorburger
Since the 1980's, the European Community (EC) has established a unified Rockwell C hardness (HRC) scale by averaging several national scales, which come from each country''s national hardness machines and diamond indenters. These indenters have significant
Since the 1980''s, the European Community (EC) has established a unified Rockwell C hardness (HRC) scale by averaging several national scales, which come from each country''s national hardness machines and diamond indenters. These indenters have
This report describes a static structural analysis of a rigid planar platform supported by elastic legs. The platform deformations are computed relative to a specified platform position and orientation. The analysis considers deformation due to static
Nien F. Zhang, Michael T. Postek, Robert D. Larrabee
The measurement of pitch in metrology instruments is through to be a benign self-compensating function. In the course of issuing the new scanning electron microscope standard SRM 2090, a new algorithm for the measurement of pitch was developed. This is
A highly rigid structure is provided using six struts connected at three upper and three lower nodes to upper and lower support structures. The joint assemblies are formed by half- spherical balls attached to the ends of each of the struts, and retained
In this paper, theoretical and experimental work on stylus flight is described. Experiments on the surfaces of different roughness specimens with sinusoidal, rectangular, triangular and random waveforms support the theoretical model, which predicts stylus