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Search Publications by: Ndubuisi George Orji (Fed)

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Displaying 51 - 75 of 78

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

Nano- and Atomic-Scale Length Metrology

December 14, 2007
Author(s)
Theodore V. Vorburger, Ronald G. Dixson, Joseph Fu, Ndubuisi G. Orji, Shaw C. Feng, Michael W. Cresswell, Richard A. Allen, William F. Guthrie, Wei Chu

Photomask Applications of Traceable Atomic Force Microscope Dimensional Metrology at NIST

October 1, 2007
Author(s)
Ronald G. Dixson, Ndubuisi G. Orji, James E. Potzick, Joseph Fu, Michael W. Cresswell, Richard A. Allen, S J. Smith, Anthony J. Walton
The National Institute of Standards and Technology (NIST) has a multifaceted program in AFM dimensional metrology. Two major instruments are being used for traceable measurements. The first is a custom in-house metrology AFM, called the calibrated AFM (C

TEM Calibration Methods for Critical Dimension Standards

April 5, 2007
Author(s)
Ndubuisi G. Orji, Ronald G. Dixson, B Bunday, M R. Bishop, Michael W. Cresswell, J Allgair
One of the key challenges in critical dimension (CD) metrology is finding suitable calibration standards. Over the last few years there has been some interest in using features measured with transmission electron microscope (TEM) as primary standards for

Application of Carbon Nanotube Probes in a Critical Dimension Atomic Force Microscope

March 1, 2007
Author(s)
B C. Park, J Choi, S J. Ahn, D H. Kim, L Joon, Ronald G. Dixson, Ndubuisi George Orji, Joseph Fu, Theodore V. Vorburger
The ever decreasing size of semiconductor features demands the advancement of critical dimension atomic force microscope (CD-AFM) technology, for which the fabrication and use of more ideal probes like carbon nanotubes (CNT) is of considerable interest

The Coming of Age of Tilt CD-SEM

March 1, 2007
Author(s)
B Bunday, J Allgair, E Solecky, C Archie, Ndubuisi George Orji
The need for 3D metrology is becoming more urgent to address critical gaps in metrology for both lithographic and etch processes. Current generation lithographic processing (ArF source, where lambda=193 nm) sometimes results in photoresist lines with re

Higher Order Tip Effects in CD-AFM Linewidth Measurements

January 1, 2007
Author(s)
Ndubuisi G. Orji, Ronald G. Dixson
In critical dimension Atomic force microscopy (CD-AFM), a source of uncertainty is the tip. Measurements made using a CD-AFM tip show an apparent broadening of the width. Usually the results can be approximated if the tip-width is known. In addition to tip

Progress on Implementation of a CD-AFM Based Reference Measurement System

March 1, 2006
Author(s)
Ndubuisi G. Orji, Angela Martinez, Ronald G. Dixson, J Allgair
The National Institute of Standards and Technology (NIST) and SEMATECH are working to address traceability issues in semiconductor dimensional metrology. In semiconductor manufacturing, many of the measurements made in the fab are not traceable to the SI

Traceable Atomic Force Microscope Dimensional Metrology at NIST

March 1, 2006
Author(s)
Ronald G. Dixson, Ndubuisi G. Orji, Joseph Fu, Michael W. Cresswell, Richard A. Allen, William F. Guthrie
The National Institute of Standards and Technology (NIST) has a multifaceted program in atomic force microscope (AFM) dimensional metrology. There are two major instruments being used for traceable measurements at NIST. The first is a custom in-house

Nano- and Atomic-Scale Length Metrology

January 1, 2006
Author(s)
Theodore V. Vorburger, Ronald G. Dixson, Joseph Fu, Ndubuisi George Orji, Shaw C. Feng, Michael W. Cresswell, Richard A. Allen, William F. Guthrie, Wei Chu
We discuss nano-scale length metrology of linewidth, step height, and line edge roughness (LER). These properties are of growing importance to the function and specification of semiconductor devices as the dimensions of semiconductor devices shrink to the

Line Edge Roughness Metrology Using Atomic Force Microscopes

January 1, 2005
Author(s)
Ndubuisi G. Orji, Theodore V. Vorburger, Joseph Fu, Ronald G. Dixson, C Nguyen, Jayaraman Raja
Line edge roughness measurements using two types of atomic force microscopes and two types of tips are compared. Measurements were made on specially prepared samples with inscribed edge roughness of different amplitudes and wavelengths. The spatial

Linewidth Measurement from a Stitched AFM Image

January 1, 2005
Author(s)
Joseph Fu, Ronald G. Dixson, Ndubuisi G. Orji, Theodore V. Vorburger, C Nguyen
Image stitching is a technique that combines two or more images to form one composite image, which provides a field of view that the originals cannot. It has been widely used in photography, medical imaging, and computer vision and graphics. For such

Traceable Pico-Meter Level Step Height Metrology

December 1, 2004
Author(s)
Ndubuisi G. Orji, Ronald G. Dixson, Joseph Fu, Theodore V. Vorburger
The atomic force microscope (AFM) increasingly being used as a metrology tool in the semiconductor industry where the features measured are at the nanometer level and continue to decrease. Usually the height sensors of the AFM are calibrated using step

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

Space-Scale Analysis of Line Edge Roughness on 193 nm Lithography Test Structures

October 1, 2003
Author(s)
Ndubuisi G. Orji, Jayaraman Raja, Theodore V. Vorburger, Xiaohong Gu
Line edge roughness (LER) is a potential showstopper for the semiconductor industry. As the width of patterned line structures decreases, LER is becoming a non-negligible contributor to resist critical dimension (CD) variation. The International Technology

Influence of analysis Algorithms on the Value of Distorted Step Height Data

September 1, 2003
Author(s)
Ndubuisi G. Orji, Jayaraman Raja, Son H. Bui, Theodore V. Vorburger
One of the most important aspects of step height evaluation are the analysis algorithms used. There algorithms assume that the profiles and images being analyzed are ideal, but real step profiles are not ideal and the analysis algorithms can influence the

Sub-Nanometer Wavelength Metrology of Lithographically Prepared Structures: A Comparison of Neutron and X-Ray Scattering

June 1, 2003
Author(s)
Ronald L. Jones, T Hu, Eric K. Lin, Wen-Li Wu, D M. Casa, Ndubuisi George Orji, Theodore V. Vorburger, P J. Bolton, Z Barclay
The challenges facing current metrologies based on SEM, AFM, and light scatterometry for technology nodes of 157 nm imaging and beyond suggest that the development of new metrologies capable of routine measurement in this regime are required. We provide

Scale-Space Analysis of Line Edge Roughness on 193 nm Lithography Test Structures

January 1, 2003
Author(s)
Ndubuisi G. Orji, Theodore V. Vorburger, Xiaohong Gu, Jayaraman Raja
Line edge roughness (LER) is a potential showstopper for the semiconductor industry. As the width of patterned line structures decreases, LER is becoming a non-negligible contributor to resist critical dimension (CD) variation. The International Technology

Surface Finish and Sub-Surface Metrology

January 1, 2003
Author(s)
Theodore V. Vorburger, Ndubuisi George Orji, Li Piin Sung, T Rodriguez
Surface finsih affects the performance of a wide variety of manufactured products ranging from road surfaces and ships to mechanical parts, microelectronics, and optics. Accordingly roughness values can vary over many orders of magnitude. A variety of