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Search Publications by: John S. Villarrubia (Fed)

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Displaying 1 - 25 of 213

A method to calibrate angular positioning errors using a laser tracker and a plane mirror

March 20, 2025
Author(s)
Balasubramanian Muralikrishnan, Katharine Shilling, Vincent Lee, Olga Ridzel, Glenn Holland, John Villarrubia
We describe a method to calibrate angular positioning errors of a rotation stage using a laser tracker (LT), a plane mirror mounted on the stage, and stationary registration nests placed around the stage. Our technique involves determining the direction of

Model Validation for Scanning Electron Microscopy

April 27, 2023
Author(s)
Olga Ridzel, Wataru Yamane, Ishiaka Mansaray, John S. Villarrubia
We are beginning projects to validate the physics models used for interpretation of electron microscopy images. In one, we will measure electron yields and energy spectra from cleaned well-characterized samples subjected to electron bombardment inside of a

Measuring Tip Shape for Instrumented Indentation Using Atomic Force Microscopy

October 12, 2021
Author(s)
Mark R. VanLandingham, John S. Villarrubia, R M. Camara
Atomic Force Microscopy (AFM) was used to determine the three-dimensional shape of probe tips used for instrumented indentation. AFM images were taken for three probe tips with several different image sizes. The geometry obtained directly from the images

Probing Electrified Liquid-Solid Interfaces with Scanning Electron Microscopy

December 2, 2020
Author(s)
Hongxuan Guo, Alexander Yulaev, Evgheni Strelcov, Alexander Tselev, Christopher M. Arble, Andras Vladar, John S. Villarrubia, Andrei Kolmakov
The mean free path of secondary electrons in aqueous solutions is on the order of a nanometer, making them a suitable probe of ultrathin electrical double layers at solid-liquid electrolyte interfaces. Employing graphene as an electron-transparent

On Low-Energy Tail Distortions in the Detector Response Function of X-Ray Microcalorimeter Spectrometers

November 21, 2019
Author(s)
Galen C. O'Neil, Paul Szypryt, Endre Takacs, Joseph N. Tan, Sean W. Buechele, Aung Naing, Young I. Joe, Daniel S. Swetz, Daniel R. Schmidt, William B. Doriese, Johnathon D. Gard, Carl D. Reintsema, Joel N. Ullom, John S. Villarrubia, Yuri Ralchenko
We use narrow spectral lines from the X-ray spectra of various highly charged ions to measure low-energy tail-like deviations from a Gaussian response function in a microcalorimeter X-ray spectrometer with Au absorbers at energies from 650 to 3320 eV. We

Research Update: Electron beam-based metrology after CMOS

July 19, 2018
Author(s)
James A. Liddle, Brian D. Hoskins, Andras Vladar, John S. Villarrubia
The strengths of and challenges facing electron-based metrology for post-CMOS technology are reviewed. Directed self-assembly, nanophotonics/plasmonics, and resistive switches and selectors, are examined as exemplars of important post-CMOS technologies

3D Nanometrology Based on SEM Stereophotogrammetry

September 18, 2017
Author(s)
Vipin N. Tondare, John S. Villarrubia, Andras Vladar
Three-dimensional (3D) reconstruction of a sample surface from scanning electron microscope (SEM) images taken at two perspectives has been known for decades. However, this method has not been widely used in the semiconductor industry for 3D measurements