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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
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
Microelectromechanical systems (MEMS) are integrally-fabricated hybrids of micromechanical and microelectronic elements which serve together as sensors, actuators, or both. While there are proprietary issues in MEMS products currently in or near commercial
Jun-Feng Song, F Rudder, Theodore V. Vorburger, J Smith
National and international comparisons in Rockwell hardness tests show significant differences. Uncertainties in the geometry of the Rockwell diamond indenters are largely responsible for these differences. By using a stylus instrument, with a series of
Textured laps can be created by slumping uniform thin films of appropriate materials over textured substrates that have been generated to the required figure. The film can easily be replaced and the lap shape is invariant since the lap substrate never
A new process for stabilizing the frequency of commercially available 543 nm He-Ne lasers is described. The stabilization method is based on anomalous dispersion of the gain medium. A total of four green lasers have been stabilized - two at the National
Reference Material (RM) 8090 is intended primarily for use in calibrating the magnification scale of a scanning electron microscope (SEM) over a wide range of magnifications, from less than 100X to greater than 300,000X. RM 8090 contains structures in both
There is a pressing need in the semiconductor industry to determine the dimensions of lithographically produced features on wafers and masks down to the l0?nm level of accuracy. Such measurements involve the accurate location of line edges, the subtraction
The ultimate purpose of the photomask in IC manufacture is to define the image to be printed on a silicon wafer. Of the many factors which affect this aerial image in the wafer stepper, some are properties of the stepper projection system and some are
By scanning a slightly tilted, smooth surface with an atomic force microscope (AFM), it is possible to obtain hysteresis loops which contain information on the nonlinearity and hysteresis in the z axis of the AFM''s piezoelectric actuator. A 15% variation
The spatial resolution, sensitivity, and accuracy required for electrical characterization of device structures in the semiconductor industry suggest that scanned probe microscopy (SPM) tools may offer an alternative to existing measurement techniques. Due
Daniel S. Sawyer, Steven D. Phillips, Gregory W. Caskey, Bruce R. Borchardt, David E. Ward, P Snoots
This document is the user manual for the NIST SRM 9983 High Rigidity Ball Bar Stand. The manual contains a list of the components that are included as part of the unit. Complete instructions for setting up and assembling the stand to support a ball bar for
Gage blocks are the primary method used by industry to standardize the measurement of dimension. This work discusses every aspect of gage block calibration, including definitions, characteristics of gage blocks, calibration by interferometry and mechanical