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Search Publications by: Ndubuisi George Orji (Fed)

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Displaying 76 - 100 of 155

Calibration of 1 nm SiC Step Height Standards

March 31, 2010
Author(s)
Theodore V. Vorburger, Albert M. Hilton, Ronald G. Dixson, Ndubuisi G. Orji, J. A. Powell, A. J. Trunek, P. G. Neudeck, P. B. Abel
We aim to develop and calibrate a set of step height standards to meet the range of steps useful for nanotechnology. Of particular interest to this community is the calibration of atomic force microscopes operating at their highest levels of magnification

Traceability: The Key to Nanomanufacturing

December 30, 2009
Author(s)
Ndubuisi George Orji, Ronald G. Dixson, Bryan Barnes, Richard M. Silver
Over the last few years key advances have been made in the area of nanomanufacturing and nanofabrication. Several researchers have produced nanostructures using either top-down or bottom-up techniques, while other groups have functionalized such structures

Results of an international photomask linewidth comparison of NIST and PTB

October 9, 2009
Author(s)
Bernd Bodermann, Detleff Bergmann, Egbert Buhr, Wolfgang Haebler-Grohne, Harald Bosse, James E. Potzick, Ronald G. Dixson, Richard Quintanilha, Michael T. Stocker, Andras Vladar, Ndubuisi George Orji
In preparation of the international Nano1 linewidth comparison on photomasks between 9 national metrology institutes, NIST and PTB have started a bilateral linewidth comparison in 2008, independent of and prior to the Nano1 comparison in order to test the

Measurement Traceability and Quality Assurance in a Nanomanufacturing Environment

September 25, 2009
Author(s)
Ndubuisi G. Orji, Ronald G. Dixson, Aaron Cordes, Benjamin Bunday, John Allgair
A key requirement for nano-manufacturing is maintaining acceptable traceability of measurements performed to determine size. Given that properties and functionality at the nanoscale are governed by absolute size, maintaining the traceability of dimensional

A moving window correlation method to reduce the distortion of SPM images

August 20, 2009
Author(s)
Wei Chu, Joseph Fu, Ronald G. Dixson, Ndubuisi G. Orji, Theodore V. Vorburger
Many scanning probe microscopes (SPMs), such as the scanning tunneling microscope (STM) and atomic force microscope (AFM), use piezoelectric actuators operating in open loop for generating the scans of the surfaces. However, nonlinearities mainly caused by

Reference Metrology in a Research Fab: The NIST Clean Calibrations Thrust

April 12, 2009
Author(s)
Ronald G. Dixson, Ndubuisi G. Orji, Joseph Fu, Thomas B. Renegar, Xiaoyu A. Zheng, Theodore V. Vorburger, Albert M. Hilton, Marc J. Cangemi, Lei Chen, Michael A. Hernandez, Russell E. Hajdaj, Michael R. Bishop, Aaron Cordes
In 2004, the National Institute of Standards and Technology (NIST) commissioned the Advanced Measurement Laboratory (AML) – a state-of-the-art, five-wing laboratory complex for leading edge NIST research. The NIST NanoFab – a 1765 m2 (19,000 ft2) clean

Comparison of Measurement Techniques for Linewidth Metrology on Advanced Photomasks

February 19, 2009
Author(s)
Stewart Smith, Andreas Tsiamis, Martin McCallum, Andrew Hourd, J Stevenson, Anthony Walton, Ronald G. Dixson, Richard A. Allen, James E. Potzick, Michael W. Cresswell, Ndubuisi George Orji
This paper compares electrical, optical, and atomic force microscope (AFM) measurements of critical dimension (CD)made on a chrome on quartz photomask. Test structures suitable for direct, on-mask electrical probing have been measured using the above three

2nd Annual Tri-National Workshop on Standards for Nanotechnology - (NIST presentations)

December 10, 2008
Author(s)
Ronald G. Dixson, Jon R. Pratt, Vincent A. Hackley, James E. Potzick, Richard A. Allen, Ndubuisi G. Orji, Michael T. Postek, Herbert S. Bennett, Theodore V. Vorburger, Jeffrey A. Fagan, Robert L. Watters
A new era of cooperation between North American National Measurement Institutes (NMIs) was ushered by the National Research Council of Canada Institute for National Measurement Standards (NRC-INMS) on February 7, 2007 when the first Tri-National workshop

Accuracy Considerations for Critical Dimension Semiconductor Metrology

September 9, 2008
Author(s)
Ronald G. Dixson, Ndubuisi G. Orji, B Bunday, J Allgair
As the size of integrated circuit features continues to decrease, the accuracy of measurements becomes more important. Due to greater emphasis on precision rather than accuracy, many of the measurements made in semiconductor fabs are not traceable to the

Through-focus Scanning and Scatterfield Optical Methods for Advanced Overlay Target Analysis

September 1, 2008
Author(s)
Ravikiran Attota, Michael T. Stocker, Richard M. Silver, Nathanael A. Heckert, Hui Zhou, Richard J. Kasica, Lei Chen, Ronald G. Dixson, Ndubuisi G. Orji, Bryan M. Barnes, Peter Lipscomb
In this paper we present overlay measurement techniques that use small overlay targets for advanced semiconductor applications. We employ two different optical methods to measure overlay using modified conventional optical microscope platforms. They are

Towards Accurate Feature Shape Metrology

March 22, 2008
Author(s)
Ndubuisi G. Orji, Ronald G. Dixson, B Bunday, J Allgair
Over the last few years, the need for shape metrology for process control has increased. A key component of shape metrology is sidewall angle (SWA). However, few instruments measure SWA directly. The critical dimension atomic force microscope (CD-AFM) is