Share Email Print
cover

Proceedings Paper

Through-focus scanning and scatterfield optical methods for advanced overlay target analysis
Author(s): Ravikiran Attota; Michael Stocker; Richard Silver; Alan Heckert; Hui Zhou; Richard Kasica; Lei Chen; Ronald Dixson; George Orji; Bryan Barnes; Peter Lipscomb
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

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 scatterfield and through-focus scanning optical microscope (TSOM) imaging methods. In the TSOM method a target is scanned through the focus of an optical microscope, simultaneously acquiring optical images at different focal positions. The TSOM images are constructed using the through-focus optical images. Overlay analysis is then performed using the TSOM images. In the scatterfield method, a small aperture is scanned at the conjugate back focal plane of an optical microscope. This enables angle-resolved scatterometry on a high-magnification optical platform. We also present evaluation of optical constants using the scatterfield method.

Paper Details

Date Published: 23 March 2009
PDF: 13 pages
Proc. SPIE 7272, Metrology, Inspection, and Process Control for Microlithography XXIII, 727214 (23 March 2009); doi: 10.1117/12.817062
Show Author Affiliations
Ravikiran Attota, National Institute of Standards and Technology (United States)
Michael Stocker, National Institute of Standards and Technology (United States)
Richard Silver, National Institute of Standards and Technology (United States)
Alan Heckert, National Institute of Standards and Technology (United States)
Hui Zhou, KT Consulting Inc. (United States)
Richard Kasica, National Institute of Standards and Technology (United States)
Lei Chen, National Institute of Standards and Technology (United States)
Ronald Dixson, National Institute of Standards and Technology (United States)
George Orji, National Institute of Standards and Technology (United States)
Bryan Barnes, National Institute of Standards and Technology (United States)
Peter Lipscomb, SEMATECH, Inc. (United States)


Published in SPIE Proceedings Vol. 7272:
Metrology, Inspection, and Process Control for Microlithography XXIII
John A. Allgair; Christopher J. Raymond, Editor(s)

© SPIE. Terms of Use
Back to Top