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Search Publications by: John S. Villarrubia (Fed)

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Displaying 51 - 75 of 110

Influence of Focus Variation on Linewidth Measurements

March 3, 2005
Author(s)
M Tanaka, John S. Villarrubia, Andras Vladar
The influence of spatial resolution on line width measurements in the critical dimension scanning electron microscope (CD-SEM) was investigated experimentally. Measurement bias variation and measurement repeatabilities of four edge detection algorithms

Issues in Line Edge and Linewidth Roughness Metrology

January 1, 2005
Author(s)
John S. Villarrubia
In semiconductor electronics applications, line edge and linewidth roughness are generally measured using a root mean square (RMS) metric. The true value of RMS roughness depends upon the length of edge or line that is measured and the chosen sampling

Scanning Electron Microscope Dimensional Metrology using a Model-based Library

January 1, 2005
Author(s)
John S. Villarrubia, Andras Vladar, Michael T. Postek
The semiconductor electronics industry places significant demands upon secondary electron imaging to obtain dimensional measurements that are used for process control or failure analysis. Tolerances for measurement uncertainty and repeatability are smaller

Test of CD-SEM Shape-Sensitive Linewidth Measurement

July 1, 2004
Author(s)
John S. Villarrubia, Andras Vladar, Michael T. Postek
In a model-based library (MBL) approach to scanning electron microscope (SEM) linewidth measurement, a library of simulation results for a range of lineshapes is searched for a match to the measured image of the unknown line. Compared to standard

Determination of Optimal Parameters for CD-SEM Measurement of Line Edge Roughness

May 1, 2004
Author(s)
B Bunday, M R. Bishop, D Mccormack, John S. Villarrubia, Andras Vladar, Theodore V. Vorburger, Ndubuisi George Orji, J Allgair
The measurement of line-edge roughness (LER) has recently become a topic of concern in the litho-metrology community and the semiconductor industry as a whole. The Advanced Metrology Advisory Group (AMAG), a council composed of the chief metrologists from

Dimensional Metrology of Resist Lines Using a SEM Model-Based Library Approach

May 1, 2004
Author(s)
John S. Villarrubia, Andras Vladar, B Bunday, M R. Bishop
The widths of 284 lines in a 193 nm resist were measured by two methods and the results compared. One method was scanning electron microscopy (SEM) of cross-sections. The other was a model-based library (MBL) approach in which top-down CD-SEM line scans of

Shape-Sensitive Linewidth Measurements of Resist Structures

January 1, 2004
Author(s)
John S. Villarrubia, Andras Vladar, Michael T. Postek
Widths of developed 193 nm resist lines were measured by two methods and compared. One method was a new model-based library method. In this method the scanning electron microscope (SEM) images corresponding to various edge shapes are simulated in advance

Tip Characterization for Dimensional Nanometrology

January 1, 2004
Author(s)
John S. Villarrubia
Abstract: Technological trends are increasingly requiring dimensional metrology at size scales below a micrometer. Scanning probe microscopy has unique advantages in this size regime, but width and roughness measurements must be corrected for imaging

Exploring and Extending the Limits of CD-SEMs' Resolution

November 1, 2003
Author(s)
Andras Vladar, Michael T. Postek, John S. Villarrubia
This study of SEM resolution is occasioned by concerns that it is no longer adequate for lithography process control in integrated circuit manufacturing. For example, according to the most recent International Technology Roadmap for Semiconductors, the in

CD-SEM Measurement of Line Edge Roughness Test Patterns for 193 nm Lithography

July 1, 2003
Author(s)
B Bunday, M R. Bishop, John S. Villarrubia, Andras Vladar
The measurement of line-edge roughness (LER) has recently become a major topic of concern in the litho-metrology community and the semiconductor industry as a whole, as addressed in the 2001 International Technology Roadmap for Semiconductors (ITRS)

CD-SEM Measurement of Line-Edge Roughness Test Patterns for 193-nm Lithography

July 1, 2003
Author(s)
B Bunday, M R. Bishop, John S. Villarrubia, Andras Vladar
The measurement of line-edge roughness (LER) has recently become a major topic of concern in the litho-metrology community and the semiconductor industry as a whole, as addressed in the 2001 International Technology Roadmap for Semiconductors (ITRS)

A Simulation Study of Repeatability and Bias in the CD-SEM

May 1, 2003
Author(s)
John S. Villarrubia, Andras Vladar, Michael T. Postek
The ability of a critical dimension scanning electron microscope (CD-SEM) to resolve differences in the widths of two lines is determined by measurement repeatability and any sample-dependent biases. In order to ascertain the dependence of these quantities

Exploring and Extending the Limits of CD-SEMs' Resolution

March 1, 2003
Author(s)
Andras Vladar, Michael T. Postek, John S. Villarrubia
This study of SEM resolution is occasioned by concerns that it is no longer adequate for lithography process control in integrated circuit manufacturing. For example, according to the most recent International Technology Roadmap for Semiconductors, the in

Scanning Electron Microscope Analog of Scatterometry

July 1, 2002
Author(s)
John S. Villarrubia, Andras Vladar, J R. Lowney, Michael T. Postek
Optical scatterometry has attracted a great deal of interest for linewidth measurement due to its high repeatability and capability of measuring sidewall shape. We have developed an analogous and complementary technique for the scanning electron microscope

Trial Shape-Sensitive Linewidth Measurement System

November 1, 2001
Author(s)
John S. Villarrubia, Andras Vladar, Michael T. Postek
This is a report for a project to develop a scanning electron microscope (SEM) based shape-sensitive linewidth measurement system by improving the method by improving the method by which SEM data are analyzed. We report significant developments in

Edge Determination for Polycrystalline Silicon Lines on Gate Oxide

August 1, 2001
Author(s)
John S. Villarrubia, Andras Vladar, J R. Lowney, Michael T. Postek
In a scanning electron microscope (SEM) top-down secondary electron image, areas within a few tens of nanometers of the line edges arc characteristically brighter than the rest of the image. In general, the shape of the secondary electron signal within

Nanoindentation of Polymers: An Overview

March 1, 2001
Author(s)
Mark R. VanLandingham, John S. Villarrubia, William F. Guthrie, G F. Meyers
Indentation measurements made with atomic force microscopy (AFM) probes are relative measurements, largely due to the lack of information regarding the tip shape of the AFM probes. Also, current tip shape calibration procedures used in depth-sensing

Shape-Sensitive Linewidth Measurement with the SEM Using a Model-Based Library

March 1, 2001
Author(s)
John S. Villarrubia, Andras Vladar, J R. Lowney, Michael T. Postek
In semiconductor electronics manufacturing, device performance often depends upon size. For example, microprocessor speed is linked to the width of transistor gates. Accurate measurement of feature width is an important but challenging problem. When a

Is a Production Level Scanning Electron Microscope Linewidth Standard Possible?

June 1, 2000
Author(s)
Michael T. Postek, Andras Vladar, John S. Villarrubia
Metrology will remain a pricipal enabler for the development and manufacture of future generations of semiconductor devices. With the potential of 130 nm and 100 nm linewidths and high aspect ratio structures, the scanning electron microscope (SEM) remains

Is a Production-Level Scanning Electron Microscope Linewidth Standard Possible?

June 1, 2000
Author(s)
Michael T. Postek, Andras Vladar, John S. Villarrubia
Metrology will remain a principal enabler for the development and manufacture of future generations of semiconductor devices. With the potential of 130 and l00-nanometer linewidths and high aspect ratio structures, the scanning electron microscope (SEM)
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