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Search Publications by: John S. Villarrubia (Fed)

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Displaying 1 - 25 of 106

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

Uncertainties in Nanometer-Scale Dimensional Metrology

July 1, 2016
Author(s)
John S. Villarrubia
These are slides used for an oral presentation made at the NIST "Workshop on Quantification of Uncertainties in Material Science." In nanometer-scale dimensional metrology, correction of probing errors, which are caused by the characteristic left/right

Virtual rough samples to test 3D nanometer-scale SEM stereo photogrammetry

March 22, 2016
Author(s)
John S. Villarrubia, Vipin N. Tondare, Andras Vladar
The combination of SEM for high spatial resolution, images from multiple angles to provide 3D information, and commercially available stereo photogrammetry software for 3D reconstruction offers promise for dimensional metrology in 3D. A method is described

Optimizing Hybrid Metrology: Rigorous Implementation of Bayesian and Combined Regression.

November 12, 2015
Author(s)
Mark Alexander Henn, Richard M. Silver, John S. Villarrubia, Nien F. Zhang, Hui Zhou, Bryan M. Barnes, Andras Vladar, Bin Ming
Hybrid metrology, e.g. the combination of several measurement techniques to determine critical dimensions, is an important approach to meet the needs of semiconductor industry. A proper use of hybrid metrology may not only yield more reliable estimates for

Scanning electron microscope measurement of width and shape of 10 nm patterned lines using a JMONSEL-modeled library

July 1, 2015
Author(s)
John S. Villarrubia, Andras Vladar, Bin Ming, Regis J. Kline, Daniel F. Sunday, Jasmeet Chawla, Scott List
The width and shape of 10 nm to 12 nm wide lithographically patterned SiO2 lines were measured in the scanning electron microscope by fitting the measured intensity vs. position to a physics-based model in which the lines’ widths and shapes are parameters

Optimizing Hybrid Metrology: Rigorous Implementation of Bayesian and Combined Regression

March 19, 2015
Author(s)
Mark Alexander Henn, Richard M. Silver, Nien F. Zhang, Hui Zhou, Bryan M. Barnes, Bin Ming, Andras Vladar, John S. Villarrubia
Hybrid metrology, e.g. the combination of several measurement techniques to determine critical dimensions, is an important approach to meet the needs of semiconductor industry. A proper use of hybrid metrology may not only yield more reliable estimates for

New Insights into Subsurface Imaging of Carbon Nanotubes in Polymer Composites via Scanning Electron Microscopy

February 4, 2015
Author(s)
Minhua Zhao, Bin Ming, Jae-Woo Kim, Luke J. Gibbons, Xiaohong Gu, Tinh Nguyen, Cheol Park, Peter T. Lillehei, John S. Villarrubia, Andras Vladar, James A. Liddle
Despite many studies of subsurface imaging of carbon nanotube (CNT)-polymer composites via scanning electron microscopy (SEM), significant controversy exists concerning the imaging depth and contrast mechanisms. We studied CNT-polyimide composites and, by

3D Monte Carlo modeling of the SEM: Are there applications to photomask metrology?

October 23, 2014
Author(s)
John S. Villarrubia, Andras Vladar, Michael T. Postek
The ability to model the effect of fields due to charges trapped in insulators with floating conductors has been added to JMONSEL (Java Monte Carlo simulator for Secondary Electrons) and applied to a simple photomask metal on glass geometry. These

Optimizing Hybrid Metrology through a Consistent Multi-Tool Parameter Set and Uncertainty Model

April 14, 2014
Author(s)
Richard M. Silver, Bryan Barnes, Nien F. Zhang, Hui Zhou, Andras Vladar, John S. Villarrubia, Regis J. Kline, Daniel Sunday, Alok Vaid
There has been significant interest in hybrid metrology as a novel method for reducing overall measurement uncertainty and optimizing measurement throughput (speed) through rigorous combinations of two or more different measurement techniques into a single

10 nm Three-Dimensional CD-SEM Metrology

April 10, 2014
Author(s)
Andras Vladar, John S. Villarrubia, Bin Ming, Regis J. Kline, Jasmeet Chawla, Scott List, Michael T. Postek
The shape and dimensions of a challenging pattern have been measured using a model-based library scanning electron microscope (MBL SEM) technique. The sample consisted of a 4-line repeating pattern. Lines were narrow (10 nm), asymmetric (different edge

The Effect of Tip Size in Calibration of Surface Roughness Specimens with Rectangular Profiles

September 2, 2013
Author(s)
Jun-Feng Song, Thomas B. Renegar, Johannes A. Soons, Balasubramanian Muralikrishnan, John S. Villarrubia, Xiaoyu A. Zheng, Theodore V. Vorburger
For the calibration of rectangular and trapezoidal profile roughness specimens, stylus tip will increase profile peak width and decrease valley width, which may cause the Ra changes (either increase or decrease, depends on the profile shape). Sometimes the