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Aaron N. Johnson, C L. Merkle, Michael R. Moldover, John D. Wright
We computed the flow of four gases (He, N 2, CO 2, and SF 6) through a critical nozzle by augmenting traditional computational fluid dynamics (CFD) with a rate equation that accounts for τ relax, a species-dependent relaxation time that characterizes the
Five parameters are used for 2D and 3D topography comparisons and measurements, those include two correlation parameters Ds and CCFmax , and three surface parameters: the r-m-s roughness Rq (or Sq for 3D), r-m-s waviness Wq and Gaussian filter long
Based on auto- and cross-correlation functions (ACF and CCF), a new surface parameter called profile (or topography) difference, Ds, has been developed for quantifying differences between 2D profiles or between 3D topographies with a single number. When Ds
Thomas W. LeBrun, T W. Hwang, I Y. Park, Jun-Feng Song, Yong-Gu Lee, Nicholas G. Dagalakis, Cedric V. Gagnon, Arvind K. Balijepalli
There are several new tools for manipulating microscopic objects. Among them, optical tweezers (OT) has two distinguishing advantages. Firstly, OT can easily release an object without the need of a complicated detaching scheme. Secondly, it is anticipated
Byoung H. Kang, J Wen, Nicholas Dagalakis, Jason J. Gorman
Flexure joints are frequently used in precision-motion stages and microrobotic mechanisms due to their monolithic construction. The joint compliance, however, can affect the static and dynamic performance of the overall mechanism. In this paper, we
Michael T. Postek, John S. Villarrubia, Andras Vladar
Advances in fundamental nanoscience, design of nanomaterials, and ultimately manufacturing of nanometer scale products all depend to some degree on the capability to accurately and reproducibly measure dimensions, properties, and performance
John S. Villarrubia, Andras Vladar, Michael T. Postek
The semiconductor electronics industry places significant demands upon secondary electron imaging to obtain dimensional measurements that are used for process control or failure analysis. Tolerances for measurement uncertainty and repeatability are smaller
Every measurement of a feature's size or placement on a wafer or photomask is made for a reason. Usually a measurement leads to a decision, often involving a process adjustment or business transaction, and there are costs and benefits attached to these
Jun-Feng Song, Theodore V. Vorburger, Li Ma, John M. Libert, Susan M. Ballou
Based on the maximum cross-correlation function, CCFmax, a new parameter called signature difference, Ds, is developed for verifying the similarity of the 2D and 3D ballistics signatures of the standard bullets and of the prototype standard casings. It is
Hyug-Gyo Rhee, Theodore V. Vorburger, Jonathan W. Lee, Joseph Fu
Discrepancies between phase shifting interferometry and white-light interferometry have been observed in step height and surface roughness measurements. The discrepancies have a strong relation to the roughness average parameter of the surface. The skewing
V W. Tsai, Theodore V. Vorburger, Ronald G. Dixson, Joseph Fu, R Koning, Richard M. Silver, Edwin R. Williams
Due to the limitations of modern manufacturing technology, there is no commercial height artifact at the sub-nanometer scale currently available. The single-atom steps on a cleaned silicon (111) surface with a height of 0.314 nm, derived from the lattice
Nanometre accuracy and resolution metrology over technically relevant areas is becoming a necessity for the progress of nanomanufacturing. At the National Institute of Standards and Technology, we are developing the Molecular Measuring Machine, a scanned
David B. Newell, John A. Kramar, Jon R. Pratt, Douglas T. Smith
This paper reviews the current status of small force metrology for quantitative instrumented indentation and atomic force microscopy (AFM), and in particular focuses on new electrical and deadweight standards of force developed at the National Institute of
Arvind K. Balijepalli, Thomas W. LeBrun, Cedric V. Gagnon, Yong-Gu Lee, Nicholas G. Dagalakis
In order to realize the flexibility optical trapping offers as a nanoassembly tool, we need to develop natural and intuitiveinterfaces to assemble large quantities of nanocomponents quickly and cheaply. We propose a system to create such aninterface that
In semiconductor electronics applications, line edge and linewidth roughness are generally measured using a root mean square (RMS) metric. The true value of RMS roughness depends upon the length of edge or line that is measured and the chosen sampling
System identification methods are presented for the estimation of the characteristic frequency of an optically trapped particle. These methods are more amenable to automated on-line measurements and are believed to be less prone to erroneous results
Sumanth B. Chikkamaranahalli, R. R. Vallance, Bradley N. Damazo, Richard M. Silver, James D. Gilsinn
Techniques based on scanning probe microscopy (SPM) are used to fabricate surface structures with dimensions ranging from 10 - 100mm. These structures have been fabricated and imaged using a scanning tunneling microscope (STM), and the STM requires the tip
Jack A. Stone Jr., Balasubramanian Muralikrishnan, John R. Stoup
We report on performance of a new form of fiber probe, which can be used in conjunction with a coordinate measuring machine (CMM) for microfeature measurement. The probe stylus is a glass fiber with a small ball (?75 ?m diameter) glued to the end. When the
A number of methods have been proposed to evaluate the reference value for intercomparisons of laboratory measurements. Methods for establishing the reference value include the arithmetic mean, weighted mean (with weights proportional to the reciprocal of
Features on photomasks used in the semiconductor industry have steadily decreased in size to fit more elements on a wafer. When the size becomes smaller than the wavelength of the light used in a microscope, simulation becomes an important part of the
John S. Villarrubia, Andras Vladar, Michael T. Postek
Abstract: The ability of a critical dimension scanning electron microscope (CD-SEM) to resolve differences in the widths of two lines depends on the instrument?s measurement repeatability and any sample dependent biases. The dependence of repeatability and
Dongjin Lee, Thomas W. LeBrun, Arvind Balijepalli, Jason J. Gorman, Cedric V. Gagnon, Daehie Hong, Esther H. Chang
This paper presents the design of a multiple beam optical tweezers instrument used for manipulating micro/nano-sized components. The basic equations used in designing the optical tweezers are derived and the stable and time-sharing multiple beam optical
This article describes activity modeling as specified by the Systems Modeling Language (SysML) and the finalization of the Unified Modeling Language version 2 (UML 2). It reviews and updates an earlier proposed alignment between Enhanced Functional Flow
Active vibration isolation is gaining increased attention in the ultra high precision applications to effectively treat the unavoidable ground vibration. The use of active vibration isolation is now being explored for the Molecular Measuring Machine (M 3)