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Displaying 26 - 50 of 60

Nanoparticle Size and Shape Evaluation Using the TSOM Method

June 1, 2012
Author(s)
Bradley N. Damazo, Ravikiran Attota, Premsagar P. Kavuri, Andras Vladar
A novel through-focus scanning optical microscopy (TSOM) method that yields nanoscale information from optical images obtained at multiple focal planes will be used here for nanoparticle dimensional analysis. The TSOM method can distinguish not only size

Patterned Defect & CD Metrology by TSOM Beyond the 22 nm Node

April 10, 2012
Author(s)
Ravikiran Attota, Abraham Arceo, Benjamin Bunday, Victor Vertanian
Through-focus scanning optical microscopy (TSOM) is a novel method [1-8] that allows conventional optical microscopes to collect dimensional information down to the nanometer level by combining two-dimensional optical images captured at several through

Residual Layer Thickness Control and Metrology in Jet and Flash Imprint Lithography

April 10, 2012
Author(s)
Ravikiran Attota, Shrawan Singhal, Sreenivasan S.V.
Jet-and-Flash Imprint Lithography (J-FIL) has demonstrated capability of high-resolution patterning at low costs. For accurate pattern transfer using J-FIL, it is imperative to have control of the residual layer thickness (RLT) of cured resist underneath

Optical microscope angular illumination analysis

March 7, 2012
Author(s)
Ravikiran Attota
For high precision applications of optical microscopes, it is critical to achieve symmetrical angular illumination intensity at the sample plane, in addition to uniform spatial intensity achieved by Köhler illumination. In this paper, first we demonstrate

Through-focus Scanning Optical Microscopy

December 31, 2011
Author(s)
Ravikiran Attota
Through-focus scanning optical microscopy (TSOM) method provides three-dimensional information (i.e. the size, shape and location) about micro- and nanometer-scale structures. TSOM, based on a conventional optical microscope, achieves this by acquiring and

Nanometrology Using Through-Focus Scanning Optical Microscopy Method

December 21, 2011
Author(s)
Ravikiran Attota, Richard M. Silver
We present an initial review of a novel through-focus scanning optical microscopy (TSOM) imaging method that produces nanometer dimensional measurement sensitivity using a conventional bright-field optical microscope. In the TSOM method a target is scanned

Three-dimensional Nanometrology with TSOM Optical Method

December 10, 2011
Author(s)
Ravikiran Attota
Through-focus scanning optical microscopy (TSOM) is a new metrology method that achieves 3D nanoscale measurement sensitivity using conventional optical microscopes; measurement sensitivities are comparable to what is typical when using scatterometry

TSOM Method for Nanoelectronics Dimensional Metrology

November 18, 2011
Author(s)
Ravikiran Attota
Through-focus scanning optical microscopy (TSOM) is a relatively new method that transforms conventional optical microscopes into truly three-dimensional metrology tools for nanoscale to microscale dimensional analysis. TSOM achieves this by acquiring and

Controlling Formation of Atomic Step Morphology on Micro-patterned Si (100)

August 9, 2011
Author(s)
Kai Li, Pradeep Namboodiri, Sumanth B. Chikkamaranahalli, Gheorghe Stan, Ravikiran Attota, Joseph Fu, Richard M. Silver
Micro scale features are fabricated on Si (100) surfaces using lithographic techniques and then thermally processed in an ultra high vacuum (UHV) environment. Samples are flash heated at 1200 °C and further annealed at 1050 °C for 18 hours. The surface

Dimensional Analysis of Through Silicon Vias Using the TSOM Method

July 12, 2011
Author(s)
Ravikiran Attota, Andrew Rudack
There is a great need for accurate, truly-3D metrology solutions that can be used for analysis of high aspect ratio features such as through-silicon-vias (TSVs). Through-focus scanning optical microscopy (TSOM) is an optical metrology method that provides

TSOM Method for Semiconductor Metrology

April 18, 2011
Author(s)
Ravikiran Attota, Ronald G. Dixson, John A. Kramar, James E. Potzick, Andras Vladar, Benjamin D. Bunday, Erik Novak, Andrew C. Rudack
Through-focus scanning optical microscopy (TSOM) is a new metrology method that achieves 3D nanoscale measurement resolution using conventional optical microscopes; measurement sensitivities are comparable to what is typical using Scatterometry, SEM and

Characterizing a Scatterfield Optical Platform for Semiconductor Metrology

December 21, 2010
Author(s)
Bryan M. Barnes, Ravikiran Attota, Richard Quintanilha, Martin Y. Sohn, Richard M. Silver
Scatterfield microscopy is the union of a high-magnification imaging platform and the angular and/or wavelength control of scatterometry at the sample surface. Scatterfield microscopy uses Köhler illumination, where each point on the source translates to a

Nanoparticle size and shape evaluation using the TSOM optical microscopy method

June 6, 2010
Author(s)
Ravikiran Attota, Richard J. Kasica, Lei Chen, Premsagar P. Kavuri, Richard M. Silver, Andras Vladar
We present a novel optical TSOM (through-focus scanning optical microscopy - pronounced as 'tee-som') method that produces nanoscale dimensional measurement sensitivity using a conventional optical microscope. The TSOM method uses optical information from

Nanoscale Measurements With the TSOM Optical Method

January 4, 2010
Author(s)
Ravikiran Attota
A novel through-focus scanning optical microscope (TSOM - pronounced as 'tee-som') technique that produces nanometer dimensional measurement sensitivity using a conventional optical microscope by analyzing images obtained at different focus positions will

Optical TSOM method for 3D interconnect metrology

November 18, 2009
Author(s)
Ravikiran Attota
There is a great need for high accurate, truly-3D metrology solutions that can be used for analysis of high aspect ratio features such as through-silicon-vias (TSVs). In this presentation we propose evaluating the viability of the newly developed through

Nanoscale Measurements with a Through-Focus Scanning-Optical-Microscope

July 15, 2009
Author(s)
Ravikiran Attota, Richard M. Silver, Thomas A. Germer
We present a novel optical technique that produces nanometer dimensional measurement sensitivity using a conventional optical microscope, by analyzing through-focus scanning-optical-microscope (TSOM) images obtained at different focus positions. In

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

Optical Critical Dimension Measurement of Silicon Grating Targets Using Back Focal Plane Scatterfield Microscopy

January 2, 2008
Author(s)
Heather J. Patrick, Ravikiran Attota, Bryan M. Barnes, Thomas A. Germer, Michael T. Stocker, Richard M. Silver, Michael R. Bishop
We demonstrate optical critical dimension measurement of lines in silicon grating targets using back focal plane scatterfield microscopy. In this technique, angle-resolved diffraction signatures are obtained from grating targets by imaging the back focal

Line Width Measurement Technique Using Through-Focus Optical Images

January 1, 2008
Author(s)
Ravikiran Attota, Richard M. Silver, Ronald G. Dixson
We present a detailed experimental study of a new through-focus technique to measure line width (CD) with nanometer sensitivity using a bright field optical microscope. This method relies on analyzing intensity gradients in optical images at different

Extending the Limits of Image-Based Optical Metrology

June 20, 2007
Author(s)
Richard M. Silver, Bryan M. Barnes, Ravikiran Attota, Jay S. Jun, Michael T. Stocker, Egon Marx, Heather J. Patrick
We have developed a set of techniques, referred to as scatterfield microscopy, in which the illumination is engineered in combination with appropriately designed metrology targets. Previously we reported results from samples with sub-50 nm sized features

Calibrated Overlay Wafer Standard

January 1, 2007
Author(s)
Michael T. Stocker, Richard M. Silver, Ravikiran Attota, Jay S. Jun
This document describes the physical characteristics of Standard Reference Material SRM 5000, provides guidance for its use in calibrating overlay (OL) tools, and gives information and precautions concerning its care and handling.Standard Reference

Fundamental Limits of Optical Critical Dimension Metrology: A Simulation Study

January 1, 2007
Author(s)
Richard M. Silver, Thomas A. Germer, Ravikiran Attota, Bryan M. Barnes, B Bunday, J Allgair, Egon Marx, Jay S. Jun
This paper is a comprehensive summary and analysis of a SEMATECH funded project to study the limits of optical critical dimension scatterometry. The project was focused on two primary elements: 1) the comparison, stability, and validity of industry models