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New Method to Enhance Overlay Tool Performance

Published

Author(s)

Ravikiran Attota, Richard M. Silver, Michael T. Stocker, Egon Marx, Jay S. Jun, M P. Davidson, Robert D. Larrabee

Abstract

New methods to enhance and improve algorithm performance and data analysis are being developed at NIST for overlay measurement applications. Both experimental data and improved theoretical optical scattering models have been used for the study. We have identified error sources that arise from (I) the optical cross talk between neighboring lines on an overlay target (ii) the selection of the window size used in the auto-correlation and (iii) the portion of the intensity profile that is used in the overlay calculation (defined as a truncated profile). Further, we suggest methods to optimally minimize these error sources. We also present a relationship between tool-induced shift (TIS) and the asymmetry in the intensity profile.
Proceedings Title
Proceedings of SPIE on Metrology, Inspection, and Process Control for Microlithography XVII, Daniel J. Herr, Editor May 2003
Volume
5038
Issue
Pt. 1
Conference Dates
February 1, 2003
Conference Location
Santa Clara, CA, USA
Conference Title
Overlay and Registration Metrology II

Keywords

optical interaction, optimization, overlay metrology, TIS, truncation

Citation

Attota, R. , Silver, R. , Stocker, M. , Marx, E. , Jun, J. , Davidson, M. and Larrabee, R. (2003), New Method to Enhance Overlay Tool Performance, Proceedings of SPIE on Metrology, Inspection, and Process Control for Microlithography XVII, Daniel J. Herr, Editor May 2003, Santa Clara, CA, USA (Accessed June 20, 2024)

Issues

If you have any questions about this publication or are having problems accessing it, please contact reflib@nist.gov.

Created April 30, 2003, Updated October 12, 2021