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Search Publications by: Heather Patrick (Fed)

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Displaying 1 - 25 of 26

Ultraviolet to Short-Wave Infrared Spectral Reflectance

October 28, 2024
Author(s)
Heather Patrick, Clarence Zarobila
The National Institute of Standards and Technology performs calibrations of spectral reflectance measurements in the ultraviolet (UV) to short-wave infrared (SWIR) spectral regions using the Robotic Optical Scattering Instrument (ROSI) and its associated

Uncertainty in global downwelling plane irradiance estimates from sintered polytetra fluoroethylene plaque radiance measurements

May 20, 2019
Author(s)
Alexandre Castagna, B. Carol Johnson, Kenneth Voss, Heidi M. Dierssen, Heather Patrick, Thomas Germer, Zhehai Shang
Global downwelling plane irradiance is a necessary variable to normalize the water-leaving radiance measurements, reducing the magnitude and spectral variabilities introduced by the incident light field. As a result, the normalized measurements, known as

A Traceable Scatterometry Measurement of a Silicon Line Grating

May 26, 2011
Author(s)
Thomas A. Germer, Heather J. Patrick, Ronald G. Dixson
In this paper, we present a spectroscopic Mueller matrix ellipsometry measurement of a silicon line grating with nominal pitch of 600 nm and line width 100 nm. An uncertainty analysis is performed on the measurement results. The results are compared to

Supercontinuum fiber laser source for reflectance calibrations in remote sensing

August 1, 2010
Author(s)
Clarence J. Zarobila, Heather J. Patrick
The Optical Technology Division of the NIST provides reference measurements of specular and diffuse reflectance of materials, including measurements that provide traceability for diffuser plaques that are used as onboard calibration standards in remote

Effect of Bandwidth and Numerical Aperture in Optical Scatterometry

March 1, 2010
Author(s)
Thomas A. Germer, Heather J. Patrick
We consider the effects of finite spectral bandwidth and numerical aperture in scatterometry measurements and discuss efficient integration methods based upon Gaussian quadrature in one dimension (for spectral bandwidth averaging) and two dimensions inside

Developing an Uncertainty Analysis for Optical Scatterometry

August 3, 2009
Author(s)
Thomas A. Germer, Heather J. Patrick, Richard M. Silver, Benjamin Bunday
This article describes how an uncertainty analysis may be performed on a scatterometry measurement. A method is outlined for propagating uncertainties through a least-squares regression. The method includes the propagation of the measurement noise as well

Scatterometry for in situ measurement of pattern reflow in nanoimprinted polymers

December 9, 2008
Author(s)
Heather J. Patrick, Thomas A. Germer, Yifu Ding, Hyun Wook Ro, Lee J. Richter, Christopher L. Soles
We use optical scatterometry to extract the time evolution of the profile of nanoimprinted lines in low and high molecular mass polymer gratings during reflow at the glass transition temperature. The data are obtained continuously during the anneal using a

Modeling the Effect of Finite Size Gratings on Scatterometry Measurements

September 1, 2008
Author(s)
Elizabeth Kenyon, Michael W. Cresswell, Heather Patrick, Thomas Germer
The interpretation of scatterometry measurements generally assumes that the grating extends over an area large enough to intercept all the illumination provided by an incident beam. However, in practice, the gratings used in scatterometry are relatively

Extraction of trench geometry and linewidth of nanoscale grating targets in (110)-oriented silicon using angle-resolved scatterometry

June 9, 2008
Author(s)
Heather J. Patrick, Thomas A. Germer, Michael W. Cresswell, Bin Li, Huai Huang, Paul S. Ho
The extraction of nanoscale dimensions and feature geometry of grating targets using signature-based optical techniques is an area of continued interest in semiconductor manufacturing. In the current work, we have performed angle-resolved scatterometry

Modeling the Effect of Finite Size Gratings on Scatterometry Measurements

February 25, 2008
Author(s)
Elizabeth Kenyon, Michael W. Cresswell, Heather Patrick, Thomas Germer
The interpretation of scatterometry measurements generally assumes that the grating extends over an area large enough to intercept all the illumination provided by an incident beam. However, in practice, the grat-ings used in scatterometry are relatively

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

Modeling and Analysis of Scatterometry Signatures for Optical Critical Dimension Reference Material Applications

May 7, 2007
Author(s)
Heather J. Patrick, Thomas A. Germer, Michael W. Cresswell, Richard A. Allen, Ronald G. Dixson, Michael R. Bishop
We use an optical critical dimension technique, matching modeled to measured scatterometry signatures, to obtain critical dimension linewidth on grating targets fabricated using the single-crystal critical dimension reference materials process. The targets

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