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the KLA-Tencor 8250R SEM, images of reticle patterns can be automatically analyzed by Klarity ProDATA for corner rounding and contact area, as well as comparison with design or wafer images. Two major mechanisms produce line end shortening. The fundamental limits of diffraction round the corners of aerial images producing a foreshortened line end for small features. This aerial image shortening is compounded by diffusion, attacking the line end from three sides. The result can be a significant amount of line end shortening that is both image and process related. References
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2 . C. A. Mack and J. E. Connors, “Fundamental Diff e re n c e s Between Positive and Negative Tone Imaging,” O p t ical/Laser Microlithography V, Pro c . , SPIE Vol. 1674 (1992) pp. 328-338, and M i c rolithography Wo r l d , Vo l . 1, No. 3 (Jul/Aug 1992) pp. 17-22. 3 . C. A. Mack, “The Natural Resolution”, M i c ro l i t h o g r a p h y Wo r l d (Fall, 1998). 4. C. A. Mack, Inside PROLITH: A Comprehensive Guide to Optical Lithography Simulation, FINLE Technologies (Austin, TX: 1997). 5. C. A. Mack, C. Sauer, S. Weaver, and J. Chabala, “Lithography Performance of Contact Holes - Part II: Simulation of the Effects of Reticle Corner Rounding on Wafer Print Perf o rmance,” Photomask and X-Ray Mask Technology VII, P ro c . , SPIE Vol. 4066 (2000) pp. 172-179.
1. S. We a v e r, M. Lu, J. Chabala, D. Ton, C. Sauer, and C. A. Mack, “Lithography Performance of Contact Holes - Part I. Optimization of Pattern Fidelity Using MPG and MPGII”, these pro c e e d i n g s .
KLA-Tencor Trade Show Calendar March 12-13
FLAVS/FSM, Orlando, Florida
March 28-29
SEMICON China, Shanghai, China
April 1
Photomask Japan, Yokohama, Japan
April 19-20
AEC/APC, Dresden, Germany
April 24-26
Quality Expo, Rosemont, Illinois
April 24-26
SEMICON Europa, Munich, Germany
May 27-30
ECS/ISTC, Shanghai, China
June 4-6
IITC, San Francisco, California
July 16-18
SEMICON West, San Francisco, California
July 18-20
SEMICON West, San Jose, California
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Spring 2001
Yield Management Solutions