Share Email Print

Proceedings Paper

End of thresholds: subwavelength optical linewidth measurement using the flux-area technique
Author(s): Peter Fiekowsky
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

The patented Flux-Area technique of metrology with optical images has been proven to provide accurately and repeatable measurements of defect sizes as small as 0.08 (mu) , and is in use in 12 leading edge mask shops and wafer fabs around the world. This paper describes the extension of this technique for linewidth measurement and the result of test on photomasks, using lines as narrow as 0.25 micrometers . Linewidths were measured with SEM and optical images analyzed with the Flux-Area technique. Results show that the new technique provides linear measurements on even the smallest lines, using visible as well as UV illumination. This technique promises to allow mask makers to continue measuring their masks optically, even as linewidths shrink much smaller than the optical wavelengths used in the measurement. Further, this technique allows older visible light system to be used for measuring even DUV masks. Finally, this technique does not require thresholds: it only requires an image and that the optical magnification be known. The technique simply measures the amount of light absorbed by a feature, the fundamental optical quality of any photomask feature.

Paper Details

Date Published: 19 July 2000
PDF: 6 pages
Proc. SPIE 4066, Photomask and Next-Generation Lithography Mask Technology VII, (19 July 2000); doi: 10.1117/12.392075
Show Author Affiliations
Peter Fiekowsky, Automated Visual Inspection (United States)

Published in SPIE Proceedings Vol. 4066:
Photomask and Next-Generation Lithography Mask Technology VII
Hiroaki Morimoto, Editor(s)

© SPIE. Terms of Use
Back to Top