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Publications

Search Publications by

Michael T. Stocker (Fed)

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Displaying 1 - 21 of 21

Addressing Quality Assurance Issues in 3D Firearm and Toolmark Imaging

April 1, 2018
Author(s)
Michael T. Stocker, Robert M. Thompson, Johannes A. Soons, Thomas B. Renegar, Xiaoyu A. Zheng
The emerging capability for measuring and analyzing the three-dimensional (3D) surface topography of forensic samples is expected to have a profound impact on firearm and toolmark identification. As forensic laboratories are working to integrate 3D

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

Photomask metrology using a 193 nm scatterfield microscope

September 30, 2009
Author(s)
Richard Quintanilha, Bryan M. Barnes, Martin Y. Sohn, Lowell P. Howard, Richard M. Silver, James E. Potzick, Michael T. Stocker
The current photomask linewidth Standard Reference Material (SRM) supplied by the National Institute of Standards and Technology (NIST), SRM 2059, is the fifth generation of such standards for mask metrology. The calibration of this mask has been usually

International photomask linewidth comparison by NIST and PTB

October 17, 2008
Author(s)
James E. Potzick, Ronald G. Dixson, Richard Quintanilha, Michael T. Stocker, Andras Vladar, Egbert Buhr, Bernd Bodermann, Wolfgang Hassler-Grohne, Harald Bosse, C.G. Frase
In preparation of the international Nano1 linewidth comparison on photomasks between 8 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

Through-focus Scanning and Scatterfield Optical Methods for Advanced Overlay Target Analysis

September 1, 2008
Author(s)
Ravikiran Attota, Michael T. Stocker, Richard M. Silver, Nathanael A. Heckert, Hui Zhou, Richard J. Kasica, Lei Chen, Ronald G. Dixson, Ndubuisi G. Orji, Bryan M. Barnes, Peter Lipscomb
In this paper we present overlay measurement techniques that use small overlay targets for advanced semiconductor applications. We employ two different optical methods to measure overlay using modified conventional optical microscope platforms. They are

Optical Critical Dimension Measurement of Silicon Grating Targets Using Back Focal Plane Scatterfield Microscopy

January 2, 2008
Author(s)
Heather J. Patrick, Ravikiran Attota, Bryan M. Barnes, Thomas A. Germer, Michael T. Stocker, Richard M. Silver, Michael R. Bishop
We demonstrate optical critical dimension measurement of lines in silicon grating targets using back focal plane scatterfield microscopy. In this technique, angle-resolved diffraction signatures are obtained from grating targets by imaging the back focal

Extending the Limits of Image-Based Optical Metrology

June 20, 2007
Author(s)
Richard M. Silver, Bryan M. Barnes, Ravikiran Attota, Jay S. Jun, Michael T. Stocker, Egon Marx, Heather J. Patrick
We have developed a set of techniques, referred to as scatterfield microscopy, in which the illumination is engineered in combination with appropriately designed metrology targets. Previously we reported results from samples with sub-50 nm sized features

Calibrated Overlay Wafer Standard

January 1, 2007
Author(s)
Michael T. Stocker, Richard M. Silver, Ravikiran Attota, Jay S. Jun
This document describes the physical characteristics of Standard Reference Material SRM 5000, provides guidance for its use in calibrating overlay (OL) tools, and gives information and precautions concerning its care and handling.Standard Reference

Koehler Illumination for High-Resolution Optical Metrology

March 1, 2006
Author(s)
Martin Y. Sohn, Bryan M. Barnes, Lowell P. Howard, Richard M. Silver, Ravikiran Attota, Michael T. Stocker
Accurate preparation of illumination is critical for high-resolution optical metrology applications such as line width and overlay measurements. To improve the detailed evaluation and alignment of the illumination optics, we have separated Koehler

The Limits of Image-Based Optical Metrology

March 1, 2006
Author(s)
Richard M. Silver, Bryan M. Barnes, Ravikiran Attota, Jay S. Jun, James J. Filliben, Juan Soto, Michael T. Stocker, P Lipscomb, Egon Marx, Heather J. Patrick, Ronald G. Dixson, Robert D. Larrabee
An overview of the challenges encountered in imaging device-sized features using optical techniques recently developed in our laboratories is presented in this paper. We have developed a set of techniques we refer to as scatterfield microscopy which allows

High-resolution Optical Metrology

May 1, 2005
Author(s)
Richard M. Silver, Ravikiran Attota, Michael T. Stocker, M R. Bishop, Lowell P. Howard, Thomas A. Germer, Egon Marx, M P. Davidson, Robert D. Larrabee
Recent advances in optical imaging techniques have unveiled new possibilities for optical metrology and optical-based process control measurements of features in the 65 nm node and beyond. In this paper we discuss methods and applications that combine

Evaluation of New In-Chip and Arrayed Line Overlay Target Designs

May 24, 2004
Author(s)
M P. Davidson, M R. Bishop, Robert D. Larrabee, Michael T. Stocker, Jay S. Jun, Egon Marx, Richard M. Silver, Ravikiran Attota
Two types of overlay targets have been designed and evaluated for the study of optical overlay metrology. They are in-chip and arrayed overlay targets. In-chip targets are three-bar two-level targets designed to be placed in or near the active device area

Evaluation of New In-Chip and Arrayed Line Overlay

May 1, 2004
Author(s)
Ravikiran Attota, Richard M. Silver, M R. Bishop, Egon Marx, Jay S. Jun, Michael T. Stocker, M P. Davidson, Robert D. Larrabee
Two types of overlay targets have been designed and evaluated for the study of optical overlay metrology. They are in-chip and arrayed overlay targets. In-chip targets are three-bar two-level targets designed to be placed in or near the active device area

Calibration Strategies for Overlay and Registration Metrology

May 1, 2003
Author(s)
Richard M. Silver, Michael T. Stocker, Ravikiran Attota, M R. Bishop, Jay S. Jun, Egon Marx, M P. Davidson, Robert D. Larrabee
Critical dimensions in current and next generation devices are driving the need for tighter overlay registration tolerances and improved overlay metrology tool accuracy and repeatability. Tool matching, performance evaluation, model-based metrology, and a

New Method to Enhance Overlay Tool Performance

May 1, 2003
Author(s)
Ravikiran Attota, Richard M. Silver, Michael T. Stocker, Egon Marx, Jay S. Jun, M P. Davidson, Robert D. Larrabee
New methods to enhance and improve algorithm performance and data analysis are being developed at NIST for overlay measurement applications. Both experimental data and improved theoretical optical scattering models have been used for the study. We have

Updated NIST Photomask Linewidth Standard

May 1, 2003
Author(s)
J Pedulla, James E. Potzick, Michael T. Stocker
NIST is preparing to issue the next generation in its line of binary photomask linewidth standards. Called SRM 2059, it was developed for calibrating microscopes used to measure linewidths on photomasks, and consists of antireflecting chrome line and space

Updated NIST Photomask Linewidth Standard

January 1, 2003
Author(s)
James E. Potzick, J Pedulla, Michael T. Stocker
NIST is preparing to issue the next generation in its line of binary photomask linewidth standards. Called SRM 2059, it was developed for calibrating microscopes used to measure linewidths on photomasks, and consists of antireflecting chrome line and space

New NIST Photomask Linewidth Standard

December 1, 2002
Author(s)
James E. Potzick, J Pedulla, Michael T. Stocker
NIST is preparing to issue the next generation in its line of binary photomask linewidth standards. Called SRM 2059, it was developed for calibrating microscopes used to measure linewidths on photomasks, and consists of antireflecting chrome line and space

Comparison of Measured Optical Image Profiles of Silicon Lines with Two Different Theoretical Models

July 1, 2002
Author(s)
Richard M. Silver, Ravikiran Attota, Michael T. Stocker, Jay S. Jun, Egon Marx, Robert D. Larrabee, B Russo, M P. Davidson
In this paper we describe a new method for the separation of too-induced measurement errors and sample-induced measurement errors. We apply the method to standard overlay target configurations. This method is used to separate the effects of the tool and

Testing Displacement-Measuring Interferometer Systems

January 1, 1998
Author(s)
Jack A. Stone Jr., Martin Schroeck, Michael T. Stocker
We have made a study of one method for testing displacement-measuring interferometer systems, a modified back-to-back comparison, that automatically compensates for changes in the optical path length between the two interferometers. Although this method