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Search Publications by: Andras E. Vladar (Fed)

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Displaying 51 - 75 of 185

Can We Get 3D CD Metrology Right?

April 19, 2012
Author(s)
Andras Vladar, John S. Villarrubia, Michael T. Postek, Petr Cizmar
Our world is three-dimensional, so are the integrated circuits (ICs), they have always been. In the past, for a long time, we’ve been very fortunate, because it was enough to measure the critical dimension (CD), the width of the resist line to keep IC

Contour Metrology using Critical Dimension Atomic Force Microscopy

April 9, 2012
Author(s)
Ndubuisi G. Orji, Ronald G. Dixson, Andras Vladar, Bin Ming, Michael T. Postek
The critical dimension atomic force microscope (CD-AFM), which is used as a reference instrument in lithography metrology, has been proposed as a supplemental instrument for contour measurement and verification. However, although data from CD-AFM is

Real-Time Image Composition with Correction of Drift Distortion

September 20, 2011
Author(s)
Petr Cizmar, Andras Vladar, Michael T. Postek
In this article, a new scanning electron microscopy (SEM) image composition technique is de- scribed, which can significantly reduce drift-distortion related image corruptions. Drift-distortion commonly causes blur and distortions in the SEM images. Such

Development of the Metrology and Imaging of Cellulose Nanocrystals

September 19, 2011
Author(s)
Michael T. Postek, Andras Vladar, John A. Dagata, Natalia Farkas, Bin Ming, Ryan Wagner, Arvind Raman, Robert J. Moon, Ronald Sabo, Theodore H. Wegner, James Beecher
The development of metrology for nanoparticles is a significant challenge. Cellulose nanocrystals (CNC) are one group of nanoparticles that have high potential economic value but present substantial challenges to the development of the measurement science

Review of Current Progress in Nanometrology with Helium Ions

September 19, 2011
Author(s)
Michael T. Postek, Andras Vladar, Bin Ming, Charles Archie
Scanning electron microscopy has been employed as an imaging and measurement tool for more than 50 years and it continues as a primary tool in many research and manufacturing facilities across the world. A new challenger to this work is the helium ion

Accurate Nanometer-Scale Imaging and Measurements with SEM

August 18, 2011
Author(s)
Bradley N. Damazo, Bin Ming, Premsagar P. Kavuri, Andras Vladar, Michael T. Postek
Scanning electron microscopes (SEMs) are incredibly versatile instruments for millimeter to nanometer scale imaging and measurements of size and shape. New methods to improve repeatability and accuracy have been implemented on the so-called Reference SEMs

Advanced Image Composition with Intra-Frame Drift Correction

July 19, 2011
Author(s)
Petr Cizmar, Andras Vladar, Michael T. Postek
Drift Corrected Image Composition (DCIC) is a real-time technique that allows for acquiring significantly more accurate images compare to traditional slow or fast imaging methods.[Ref.] It is especially useful in nanometer-scale imaging and metrology

TSOM Method for Semiconductor Metrology

April 18, 2011
Author(s)
Ravikiran Attota, Ronald G. Dixson, John A. Kramar, James E. Potzick, Andras Vladar, Benjamin D. Bunday, Erik Novak, Andrew C. Rudack
Through-focus scanning optical microscopy (TSOM) is a new metrology method that achieves 3D nanoscale measurement resolution using conventional optical microscopes; measurement sensitivities are comparable to what is typical using Scatterometry, SEM and

Advances in Modeling of Scanning Charged-Particle-Microscopy Images

September 19, 2010
Author(s)
Petr Cizmar, Andras Vladar, Michael T. Postek
Modeling scanning electron microscope (SEM) and scanning ion microscope images has recently become necessary, because of its ability to provide repeatable images with a priori determined parameters. Modeled artificial images have been used in evaluation of

NEW Scanning Electron Microscope Magnification Calibration Reference Material (RM) 8820

August 19, 2010
Author(s)
Michael T. Postek, Andras Vladar, William J. Keery, Michael Bishop, Benjamin Bunday, John Allgair
Reference Material 8820 (RM 8820) is a new scanning electron microscope calibration reference material for nanotechnology and nanomanufacturingtion recently released by NIST. This standard was developed to be used primarily for X and Y scale (or

Reference Material (RM) 8820: A Versatile New NIST Standard for Nanometrology

July 19, 2010
Author(s)
Michael T. Postek, Andras Vladar, William J. Keery, Michael R. Bishop, Benjamin Bunday, John Allgair
A new multipurpose instrument calibration standard has been released by NIST. This standard was developed to be used primarily for X and Y scale (or magnifi cation) calibrations of scanning electron microscopes from less than 10 times magnification to more

Nanoparticle size and shape evaluation using the TSOM optical microscopy method

June 6, 2010
Author(s)
Ravikiran Attota, Richard J. Kasica, Lei Chen, Premsagar P. Kavuri, Richard M. Silver, Andras Vladar
We present a novel optical TSOM (through-focus scanning optical microscopy - pronounced as 'tee-som') method that produces nanoscale dimensional measurement sensitivity using a conventional optical microscope. The TSOM method uses optical information from

Proximity-associated errors in contour metrology

March 31, 2010
Author(s)
John S. Villarrubia, Ronald G. Dixson, Andras Vladar
In contour metrology the CD-SEM (critical dimension scanning electron microscope) assigns a continuous boundary to extended features in an image. The boundary is typically assigned as a simple function of the signal intensity, for example by a brightness

Sample Preparation Protocols for Realization of Reproducible Characterization of Single-walled Carbon Nanotubes

December 1, 2009
Author(s)
Angela R. Hight Walker, Jeffrey A. Fagan, Stephanie A. Hooker, Michael T. Postek, Stephen A. Wise, Andras Vladar, Rolf L. Zeisler
Harmonized sample pre-treatment is an integral first step in ensuring metrological quality of measurements as regards repeatability, inter-laboratory reproducibility and commutability. The development of standard preparation methods for SWCNT samples is

Results of an international photomask linewidth comparison of NIST and PTB

October 9, 2009
Author(s)
Bernd Bodermann, Detleff Bergmann, Egbert Buhr, Wolfgang Haebler-Grohne, Harald Bosse, James E. Potzick, Ronald G. Dixson, Richard Quintanilha, Michael T. Stocker, Andras Vladar, Ndubuisi George Orji
In preparation of the international Nano1 linewidth comparison on photomasks between 9 national metrology institutes, NIST and PTB have started a bilateral linewidth comparison in 2008, independent of and prior to the Nano1 comparison in order to test the

Nanometrology Solutions Using an Ultra-High Resolution In-lens SEM

September 1, 2009
Author(s)
Michael T. Postek, Andras Vladar, John S. Villarrubia
The imaging and measurement of nanostructures such as particles, carbon nanotubes, and quantum dots have placed new demands on the high resolution imaging capabilities of scanning electron microscopes. A barrier to accurate dimensional metrology is the

Optimization of Accurate SEM Imaging by Use of Artificial Images

May 22, 2009
Author(s)
Petr Cizmar, Andras Vladar, Michael T. Postek
Today the vast majority of the scanning electron microscopes (SEMs) are incapable of taking repeatable and accurate images at high magnifications. Geometric distortions are common, so are drift, vibration, and problems related to disturbing electro

On the Sub-Nanometer Resolution of Scanning Electron and Helium Ion Microscopes

March 1, 2009
Author(s)
Andras Vladar, Michael T. Postek, Bin Ming
All forms of microscopy are being pushed to the limit by nanotechnology. Hence, there is a relentless quest to achieve better and better resolution with various electron and ion microscopes and to monitor and maintain these instruments to achieve the best

Understanding Imaging and Metrology with the Helium Ion Microscope

March 1, 2009
Author(s)
Michael T. Postek, Andras Vladar, Bin Ming
The development of accurate metrology for the characterization of nanomaterials is one barrier to innovation confronting all phases of nanotechnology. Ultra-high resolution microscopy is a key technology needed to achieve this goal. But, current microscope