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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
Ronald G. Dixson, Theodore V. Vorburger, P Sullivan, V W. Tsai, T Mcwaid
Atomic force microscope (AFM) measurements are being used increasingly for metrological applications such as semiconductor process development and control. Common types of measurements are those of feature spacing (pitch), feature height (or depth), and
An uncertainty procedure is used for reporting the NIST surface finish and microform calibration uncertainties. The combined standard uncertainty is a combination of the uncertainty from the geometric non-uniformity of the measured surface, and the
In-process electrochemical dressing insures true, sharp, stable wheels for efficient ceramic grinding. To better implement electrochemical dressing, we couple laboratory studies based on a potentiostat with shop floor grinding runs. To do this, a calomel
Jack A. Stone Jr., Alois Stejskal, Lowell P. Howard
A dither in path length can dramatically improve the accuracy of wavelength-shift methods used for absolute distance interferometry. Here we report how a dither improves the accuracy of absolute distance measurement by two orders of magnitude, reducing
Robert Russell, John L. Michaloski, Keith A. Stouffer
The Advanced Deburring and Chamfer System is robotic workcell designed to put precision chamfers on parts made with hard metals. The project was funded by the United States Navy so that the technology developed could be applied to their air defense systems
Christopher J. Evans, R E. Parks, P Sullivan, John S. Taylor
Commercial software in modern interferometers used in optical testing frequently fit the wave-front or surface-figure error to Zernike polynomials; typically 37 coefficients are provided. We provide visual representations of these data in a form that may
Jun-Feng Song, F Rudder, Theodore V. Vorburger, J Smith
Based on a stylus technique, a microform calibration system was developed at NIST for the direct verification of Rockwell diamond indenters. The least-squares radius and profile deviations, cone angle and cone flank straightness, and the holder axis
Broadening of image features due to non-vanishing tip size is a well-known imaging artifact in scanned probe microscopy (SPM) topographs. This need not be a serious limitation for some types of metrology (e.g. pitch or height), but it is significant for
A new National Institute of Standards and Technology scanning electron microscope magnification calibration standard has been fabricated and distributed in production prototype form. The SRM 2090A samples contain structures ranging in pitch from 3000 um to
Zeina J. Kubarych, J Huennekens, R K. Namiotka, J Sagle
The self-broadening rate coefficients of the cesium D1 [62S1/2 - 62P1/2] and D2 [62S1/2 - 62P3/2] resonance lines are determined from the 62P1/2 --> 62D3/2, 62D3/2---> 72D3/2 and 62P3/2 --> 72D5/2 transition lineshapes, which are mapped out using single
We describe the interferometric testing of a slow (f/16 at the center of curvature) off-axis parabola, intended for use in an x-ray spectrometer, that uses a spherical wave front matched to the mean radius of the asphere. We find the figure error in the
The possibility of implementing Feynman''s proposal for achieving ultraminiaturization by an iterative process of three-dimensional machines making ever-smaller three-dimensional machines is considered in the nature of a thought experiment. A large array
The first NIST-traceable SEM magnification calibration standard designed to meet the particular needs of the micromanufacturing industry has been fabricated and characterized in production prototype form. The SRM 2090A samples contain structures ranging in