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Bradley N. Damazo, Andras Vladar, Alice V. Ling, Alkan Donmez, Michael T. Postek, Crossley E. Jayewardene
This paper describes the design and implementation of a system for monitoring the performance of a critical dimension measurement scanning electron microscope (CD-SEM). Experiments were performed for tests involving diagnosis of the vacuum system and
Ronald G. Dixson, Ndubuisi G. Orji, Joseph Fu, V W. Tsai, E. C. Williams, Theodore V. Vorburger, H Edwards, D Cook, P West, R Nyffenegger
Atomic force microscopes (AFMs) are used in the semiconductor industry for a variety of metrology purposes. Step height measurements at the nanometer level and roughness measurements at sub-nanometer levels are often of interest. To perform accurate
To address a fundamental need in stable isotope metrology, the National Institute of Standards and Technology (NIST) has established a Web-based interactive data processing system accessible through a common gateway interface (CGI) program on the internet
Asbat E. Bazaev, Ilmutdin Abdulagatov, Joe W. Magee, Emil Bazaev, Michail Rabezkii
The PVT relationships of toluene were measured in the near-critical and supercritical regions. Measurements were made using a constant-volume peizometer immersed in a precision thermostat. The volume of the piezometer V PT was corrected for both
The difficulty in manufacturing Rockwell diamond indenters to the required geometric specifications has resulted in most commercially manufactured indenters to vary in shape from one indenter to another. This difference in shape is thought to be a major
A recent workshop at the National Institute of Standards and Technology (NIST) identified research and standards that will benefit users and manufacturers of mass flow controllers and related equipment. The workshop identified problems with flow
Electromagnetic scattering of an incident plane monochromatic wave by dielectric or finitely conducting infinite cylinders of arbitrary shape, possibly in the presence of a substrate, can be reduced to the solution of scalar Helmholtz equations in two
The fields scattered by a homogeneous dielectric or finitely conducting object can be obtained from two tangential vector fields, the components of the electric and magnetic fields, on the interface. We have adapted the single-integral-equation method for
Metrology is a principal enabler for the development and manufacture of current and future generations of semiconductor devices. With the potential of 130, 100 nanometer and even smaller linewidths and high aspect ratio structures, the scanning electron
Thomas R. Kramer, John Evans, Simon P. Frechette, John A. Horst, Hui-Min Huang, Elena R. Messina, Frederick M. Proctor, William G. Rippey, Harry A. Scott, Theodore V. Vorburger, Albert J. Wavering
This is an analysis of standards related to dimensional metrology, with recommendations regarding standards development. The analysis focuses on the degree to which existing and developing standards provide a complete set of non-overlapping specifications
Michael T. Postek, Andras Vladar, Robert D. Larrabee
Reference Material (RM 8091) is intended primarily for use in checking the sharpness performance of scanning electron microscopes. It is supplied as a small (2 rnrn x 2 rnm) diced semiconductor chip. This sample is capable of being mounted directly on to a
Residual dipolar couplings can provide powerful restraints for determination and refinement of the solution structure of macromolecules. The application of these couplings in nucleic acid structure elucidation can have an especially dramatic impact since
Jon R. Pratt, David B. Newell, Edwin R. Williams, Douglas T. Smith, John A. Kramar
The National Institute of Standards and Technology has launched a five-year project to traceably link the International System of Units (SI) to forces between 10 -8N and 10 -2N. In this paper, we give a background and overview of this project, discuss the
To eliminate measurement-base trade barriers to international commerce, Key Comparisons (KCS) are now being planned in the newly formed Working Group for Fluid Flow (WGFF) in the CIPM to quantify the equivalency of the flow standards maintained in the
Steven D. Phillips, William T. Estler, Theodore D. Doiron, K Eberhardt, M Levenson
This paper is a detailed discussion of the technical aspects of the calibration process with emphasis on the definition of the measurand, the conditions under which the calibration results are valid, and the subsequent use of the calibration results in
Theodore V. Vorburger, Christopher J. Evans, William T. Estler
Traceable optics metrology is not an expensive overhead. Rather it can improve NASA's procurement process and eliminate costly Hubble-like mistakes. Improved procurement? In deciding if a part meets specification, ISO Standard 14253, Part 1 [1] states that
John S. Villarrubia, Andras Vladar, J R. Lowney, Michael T. Postek
In semiconductor electronics manufacturing, device performance often depends upon size. For example, microprocessor speed is linked to the width of transistor gates. Accurate measurement of feature width is an important but challenging problem. When a
These Web pages are intended primarily as a computational tool that can be used to calculate the refractive index of air for a given wavelength of light and given atmospheric conditions (air temperature, pressure, and humidity). The calculations are
Surface finish and imperfections are important properties of optical surfaces because they are caused by manufacturing limitations or defects and are linked to degradation of optical performance. Surface finish or surface roughness constitutes the numerous
We report measurements and a model of gas flow through a helical duct of rectangular cross section. The measurements on helium, nitrogen, argon, and sulfur hexafluoride yielded molar flow rates from observations of the rate of rise of pressure in a known
This paper reports on the past, present, and future of length and dimensional measurements at NIST. It covers the evolution of the SI unit of length through its three definitions and the evolution of NBS-NIST dimensional measurement from early linescales