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Search Publications by: Bob R. Keller (Fed)

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Displaying 1 - 25 of 46

Advancing Measurement Science for Microelectronics: CHIPS R&D Metrology Program

February 13, 2024
Marla L. Dowell, Hannah Brown, Gretchen Greene, Paul D. Hale, Brian Hoskins, Sarah Hughes, Bob R. Keller, R Joseph Kline, June W. Lau, Jeff Shainline
The CHIPS and Science Act of 2022 called for NIST to "carry out a microelectronics research program to enable advances and breakthroughs....that will accelerate the underlying R&D for metrology of next-generation microelectronics and ensure the

STEM-in-SEM: A Re-Emerging Material Measurement Approach

June 1, 2022
Bob R. Keller, Benjamin Caplins, Jason Holm
Scanning transmission electron microscopy performed in a scanning electron microscope (STEM-in-SEM) is undergoing a striking resurgence, with continuing developments in methodology and hardware, as well as applications to a wide range of materials in

STEM-in-SEM: A Re-Emerging Material Measurement Approach

September 21, 2021
Bob R. Keller
Analytical STEM-in-SEM has undergone a striking resurgence in terms of both methodology development and applications over the past 10 to 15 years, driven in part by the significant technological potential promised by low-dimensional structures such as

Orientation Mapping of Graphene Using 4D STEM-in-SEM

October 13, 2020
Benjamin W. Caplins, Jason D. Holm, Ryan M. White, Robert R. Keller
A scanning diffraction technique is implemented in the scanning electron microscope. The technique, referred to as 4D STEM-in-SEM (four-dimensional scanning transmission electron microscopy in the scanning electron microscope), collects a diffraction

Grain Orientation Mapping of Graphene in a Scanning Electron Microscope

May 1, 2019
Benjamin W. Caplins, Jason D. Holm, Robert R. Keller
A scanning transmission electron diffraction method is developed for use in the scanning electron microscope to perform orientational imaging microscopy of 2D materials. The method can generate grain orientational maps of monolayer graphene over a field of

Transmission Imaging with a Programmable Detector in a Scanning Electron Microscope

September 13, 2018
Benjamin W. Caplins, Jason D. Holm, Robert R. Keller
A new type of angularly selective electron detector for use in a scanning electron microscope is presented. The detector leverages a digital micromirror device (DMD) to take advantage of the benefits of two-dimensional (2D) imaging detectors and high

A workshop report on “Electron Microscopy Frontiers: Challenges and Opportunities”

December 21, 2017
June W. Lau, John E. Bonevich, Andrew A. Herzing, Ann C. Chiaramonti Debay, Robert R. Keller
For two days beginning on March 8, 2017, a planning workshop entitled “Electron Microscopy Frontiers: Opportunities and Challenges” was hosted by the Material Measurement Laboratory (MML) of the National Institute of Standards and Technology (NIST). Grass

Acceptance Angle Control for Improved Transmission Imaging in an SEM

March 1, 2017
Jason D. Holm, Robert R. Keller
This contribution presents a simple, cost-effective modular aperture system enabling comprehensive acceptance angle control for STEM-in-SEM imaging. The system is briefly described, and different ways to use it are explained. To demonstrate the utility of

Angularly-Selective Transmission Imaging in a Scanning Electron Microscope

May 5, 2016
Jason D. Holm, Robert R. Keller
This contribution presents recent advances in imaging control conditions for transmission scanning electron microscopy (t-SEM) by means of angularly-selective electron collection with a commercial scanning transmission electron microscopy-in-scanning

Beam broadening in transmission EBSD

March 16, 2015
Robert R. Keller, Katherine P. Rice, Mark Stoykovich
Transmission electron backscatter diffraction (t-EBSD), also known as transmission electron forward scatter diffraction (t-EFSD) or transmission Kikuchi diffraction in the SEM (TKD-SEM), can provide significant improvements in spatial resolution over

New Measurements on the Minimum and Maximum Sample Sizes in t-EBSD

October 9, 2013
Roy H. Geiss, Robert R. Keller, Katherine P. Rice
The technique of acquiring transmission electron diffraction patterns in the scanning electron microscope, SEM, using components of commercially available electron backscattered diffraction equipment, EBSD, normally used in a reflection geometry, was first

Giant Secondary Grain Growth in Cu Films on Sapphire

August 1, 2013
David L. Miller, Mark W. Keller, Justin Shaw, Katherine P. Rice, Robert Keller, Kyle M. Diederichsen
Single crystal metal films on insulating substrates are attractive for microelectronics and other applications, but they are difficult to achieve on macroscopic length scales. The conventional approach to obtaining such films is epitaxial growth at high

What's in a 'NYM?

July 1, 2013
Robert R. Keller
The field of electron microscopy, by its very diverse nature, abounds with acronyms: AEM, EF-TEM, ESEM, FE-SEM, HREM, HRTEM, HVEM, SEM, STEM, TEM, and VP-SEM, to name some instruments alone. Add in the different forms of data that these instruments might