Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications by: Thomas A. Germer (Fed)

Search Title, Abstract, Conference, Citation, Keyword or Author
Displaying 26 - 50 of 194

Scattered Light Analysis of Birefringent Coatings for Distributed Polarization Rotators

October 20, 2016
Author(s)
Katelynn A. Sharma, Thomas Germer, Christopher Smith, Jonathan Zuegel, James B. Oliver, Thomas G. Brown
We characterize scattered light in polarization optics designed to maintain uniform illumination on target during spherical direct drive fusion experiments. An optical scatter instrument is used to measure the scatter distribution in the forward and

Improved measurement capabilities at the NIST EUV Reflectometry Facility

August 1, 2014
Author(s)
Charles S. Tarrio, Steven E. Grantham, Thomas A. Germer, Jack C. Rife, Thomas B. Lucatorto, Mike Kriese, Yuriy Platonov, Licai Jiang, Jim Rodriguez
The NIST Extreme Ultraviolet (EUV) Reflectometry Facility was designed in the 1990s to accommodate the largest multilayer optics envisioned at that time. However, with increasing power requirements for an EUV scanner, source collection optics have grown

Angle-resolved diffuse reflectance and transmittance

July 1, 2014
Author(s)
Thomas A. Germer, J C. Stover, Sven Schroeder
This chapter will cover the topic of bidirectional reflectance distribution function [BRDF] measurements. These measurements, like the diffuse reflectance and transmittance measurements described in the previous chapter, cover the gamut from highly

Dispersive Methods

July 1, 2014
Author(s)
Arnold A. Gaertner, Howard Yoon, Thomas Germer
Chapter 3 will discuss dispersive means of obtaining spectral resolution in spectrophotometry. These methods are used to spatially disperse or separate the various wavelengths of optical electromagnetic radiation to enable analysis of material properties

Preface and Introduction

July 1, 2014
Author(s)
Thomas A. Germer, Joanne C. Zwinkels, Benjamin K. Tsai
This constitutes the front matter (preface and introductory chapter) to the book, "Spectrophotometry: Accurate Measurements of the Optical Properties of Materials," The introduction presents a short history of spectrophotometry. A very brief description of

Theoretical Concepts in Spectrophotometric Measurements

July 1, 2014
Author(s)
Thomas A. Germer, Joanne C. Zwinkels, Benjamin K. Tsai
This chapter will describe some of the theoretical concepts of obtaining optical properties from spectrophotometric measurements. The optical properties of interest can be the spectrophotometric quantities themselves or the calculated optical constants

Gaps Analysis for CD Metrology Beyond the 22 nm Node

April 10, 2013
Author(s)
Benjamin D. Bunday, Thomas Germer, Victor H. Vartanian, Aaron Cordes, Aron Cepler, Charles Settens
This paper will examine the future for critical dimension (CD) metrology. First we will present the extensive list of applications for which CD metrology solutions are needed, showing commonalities and differences among the various applications. We will

Intercomparison between optical and x-ray scatterometry measurements of FinFET structures

April 8, 2013
Author(s)
Paul Lemaillet, Thomas Germer, Regis J. Kline, Daniel Sunday, Chengqing C. Wang, Wen-Li Wu
In this paper, we present a comparison of profile measurements of vertical field effect transistor (FinFET) fin arrays by optical critical dimension (OCD) metrology and critical dimension small angle X-ray scattering (CD-SAXS) metrology. Spectroscopic

Remote sensing of chiral signatures on Mars

November 1, 2012
Author(s)
William Sparks, James H. Hough, Thomas Germer, Frank Robb, Ludmilla Kolokolova
We describe circular polarization as a remote sensing diagnostic of chiral signatures which may be applied to Mars. The remarkable phenomenon of homochirality provides a unique biosignature which can be amenable to remote sensing through circular

Anisotropic, Hierarchical Surface Patterns via Surface Wrinkling of Nanoimprinted Polymer Films

October 22, 2012
Author(s)
Junghyun Lee, Hyun W. Ro, Rui Huang, Thomas Germer, Paul Lemaillet, Christopher Soles, Christopher Stafford
we demonstrated the wrinkling behavior of nanopatterned PS films, whose wrinkle wavelength and resultant morphology depend strongly on geometric parameters of surface patterns as well as the direction of the applied strain relative to the nanopattern

Upper roughness limitations on the TIS/RMS relationship

September 27, 2012
Author(s)
J C. Stover, Sven Schroeder, Thomas Germer
The relationship between total integrated scatter (TIS) and root mean square (rms) roughness was developed in the radar literature and enabled the first use of scatter measurements to monitor optical roughness. This relationship has been used and misused

A compact and robust method for full Stokes spectropolarimetry

August 1, 2012
Author(s)
William Sparks, Thomas Germer, John MacKenty, Frans Snik
We present an approach to spectropolarimetry which requires neither moving parts nor time dependent modulation, and which o ers the prospect of achieving high sensitivity. The concept, which is one of those generically known as channeled polarimetry, is to

Out-of-plane Stokes imaging polarimeter for early skin cancer diagnosis

July 1, 2012
Author(s)
P. Ghassemi, Paul Lemaillet, Thomas Germer, J. W. Shupp, S. Venna, M. E. Boisvert, K. E. Flanagan, M. H. Jordan, J. C. Ramella-Roman
Optimal treatment of skin cancer before it metastasizes depends critically on early diagnosis and treatment. Imaging spectroscopy and polarized remittance have been utilized in the past for diagnostic purposes, but valuable information can be also obtained

Differential matrices for depolarizing media

March 1, 2012
Author(s)
Thomas A. Germer
The evolution of a Stokes vector through depolarizing media is considered. A general form for the differential matrix is derived that is appropriate in the presence of depolarization, and is parameterized in a manner that ensures that it yields, upon

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

Effects of Roughness on Scatterometry Signatures

May 26, 2011
Author(s)
Martin Foldyna, Thomas Germer, Brent Bergner
We used azimuthally-resolved spectroscopic Mueller matrix ellipsometry to study a periodic silicon line structure with and without artificially-generated line edge roughness (LER). Grating profiles were determined from multiple azimuthal configurations