Share Email Print

Proceedings Paper

Advanced Optical Overlay Measurement System
Author(s): Daniel R. Cote; Robert H. Clayton; Jeanne E. Lazo-Wasem
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

The successful implementation of advanced lithographic systems into high volume semiconductor fabrication has been hampered by the inability to monitor overlay using actual production wafers. While electrical probe techniques provide the necessary precision to characterize a lithographic system, special wafers and masks or reticles are required. This paper describes a new overlay measurement system (hereafter referred to as OMS) developed to use small targets placed on actual production wafers and masks or reticles. Using a simple detection scheme and a standard microscope, the system can rapidly measure up to 1000 sites per wafer. The system is designed for a precision of better than 0.05 microns (3σ) and measurement time between 1.5 and 3 seconds (including travel) per site. The system software can present vector plots as well as individual error coefficients. Resultant distortion, alignment, and magnification errors are calculated to aid in the optimization of the stepper or scanner system overlay.

Paper Details

Date Published: 1 January 1987
PDF: 10 pages
Proc. SPIE 0772, Optical Microlithography VI, (1 January 1987); doi: 10.1117/12.967041
Show Author Affiliations
Daniel R. Cote, The Perkin-Elmer Corporation (United States)
Robert H. Clayton, The Perkin-Elmer Corporation (United States)
Jeanne E. Lazo-Wasem, The Perkin-Elmer Corporation (United States)

Published in SPIE Proceedings Vol. 0772:
Optical Microlithography VI
Harry L. Stover, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?