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Robert D. Larrabee, Richard M. Silver, M P. Davidson
In the late 1970's Dr. Diana Nyyssonen demonstrated that the National Institute of Standards and Technology (NIST) could optically calibrate photomask linewidth standards that were narrower than the classical resolution limit of a conventional bright-field
E Laub, J Huennekens, R K. Namiotka, Zeina J. Kubarych, I Prodan, J La civita, S Webb, I Mazsa
We report the results of an optical-optical double resonance experiment to determine the NaK (3 1PI) state potential energy curve. In the first step, a narrow band cw laser (PUMP) is tuned to line center of a particular 2(A) (1 SIGMA+)(v?, J?) 1(X) (1
Steven D. Phillips, Bruce R. Borchardt, Daniel S. Sawyer, William T. Estler, K Eberhardt, M Levenson, Marjorie A. McClain, Ted Hopp
We describe a Monte Carlo simulation technique where known information about a metrology system is employed as a constraint to distinguish the errors associated with the instrument under consideration from the set of all possible instrument errors. The
Joseph Fu, V W. Tsai, R Koning, Ronald G. Dixson, Theodore V. Vorburger
Recently, measuring Si(111) single atomic steps prompted us to investigate the measuring technique. The section technique is the most popular method for measuring the height. By measuring a simulated Si(111) atomic step, we have found it could have an
Minimizing the uncertainty in the calibration of accelerometers by the reciprocity method requires minimizing the cross-axis component of the induced motion, and the distortion of its waveform. Minimizing the uncertainty in the calibration of
Jack A. Stone Jr., Lowell P. Howard, Alois Stejskal
Diode lasers are becoming increasingly important in length metrology. In particular, the tunability of diode lasers makes them attractive for applications such as absolute distance interferometry (ADI). In this paper we describe the current status of our
The measurement of feature sizes on integrated circuit photomasks and wafers is an economically important and technically challenging application of nanometrology. The displacement measuring laser heterodyne interferometer is a popular tool in such
Steven D. Phillips, K Eberhardt, William T. Estler
This paper discusses the distinction between measurement uncertainty, measurement errors and their role in the calibration process. The issue of including uncorrected bias is addressed and a method to extend the current ISO Guide to the Expression of
When a continuous quantity is measured with a digital instrument or digitized for further processing, a measurement uncertainty component is incurred from quantization of the continuous variable. This uncertainty can be reduced by oversampling and
This report summarizes research projects measurement method developments, calibration and testing services, and data evaluation activities that were carried out during calendar year 1998 in the NIST Physics Laboratory. These activities are in the areas of
Thomas W. LeBrun, S H. Southworth, G B. Armen, M A. MacDonald, Y Azuma
Partial cross sections for Ar K-LZL3(1 D2)np, n=4 and 5 spectator Auger states excited by x-ray absorption across the K-edge were measured and compared with calculations based on the theory or radiationless resonant Raman scattering. Core relaxation and
In this paper, reference position markers are proposed for self-calibration and error compensation. Self-calibration of x-y motion guides is discussed with a focus on the orthogonality calibration. An algorithm is developed using a closure method and
Jack A. Stone Jr., Alois Stejskal, Lowell P. Howard
In this paper we describe the status of our research on the use of diode lasers for absolute distance interferometry, and we discuss the major sources of uncertainty that limit the accuracy of this technique for distance measurement. We have primarily
Michael T. Postek, Marylyn H. Bennett, N J. Zaluzec
When a contamination event occurs in a semiconductor fab, a process engineer must act quickly to find the cause. It is cost-prohibitive to maintain a full complement of analytical tools in a fab that would be necessary to identify very small particles and
Michael T. Postek, Marylyn H. Bennett, N J. Zaluzec
When a contamination event occurs in a semiconductor fab, a process engineer must act quickly to find the cause. It is cost-prohibitive to maintain a full compliment of analytical tools in a fab that would be necessary to identify very small particles and
Technological trends are increasingly requiring dimensional metrology at size scales below a micrometer. Scanning probe microscopy has unique advantages in this size regime, but width and roughness measurements must be corrected for imaging artifacts. This
A variety of different kinds of photomask critical dimensions (CD) metrology tools are available today to help meet current and future metrology challenges. These tools are based on different operating principles, and have different cost, throughput
We describe the use of Bayesian inference to include prior information about the value of the measurand in the calculation of measurement uncertainty. Typical examples show this can, in effect, reduce the expanded uncertainty by up to 85 %. The application
We describe a simple, convenient method for measuring nonlinearities in displacement-measuring Michelson interferometers. Nonlinearities with a spatial periodicity of one optical fringe are a well-known source of error in precision interferometry. Our
Michael T. Postek, Marylyn H. Bennett, N J. Zaluzec, Thomas E. Wheatley, Samuel N. Jones
A portion of the mission of the NIST Manufacturing Engineering Laboratory (MEL) is to improve and advance length metrology in aid of U.S. Industry. This responsibility is found within the Precision Engineering Division (PED). The successful development of
In microform metrology, complex 3-D surface features in the micrometer range must be quantified for their space and size including dimensions, curves, angles, profile deviations, and alignment errors, as well as surface roughness with measurement