29 June 1998 Aberration evaluation and tolerancing of 193-nm lithographic objective lenses
Author Affiliations +
Proceedings Volume 3334, Optical Microlithography XI; (1998); doi: 10.1117/12.310756
Event: 23rd Annual International Symposium on Microlithography, 1998, Santa Clara, CA, United States
Abstract
Described here is an approach to aberration tolerancing utilizing aerial image parameterization based on photoresist capability. A minimum aerial image metric is determined from either a characterized resist process or desirable resist attributes and includes definition of resist exposure, diffusion, and development properties. Minimum aerial image requirements can then be correlated to resist performance to allow for the evaluation of various feature sizes and types. This allows, for example, the prediction of lens performance through focus, across the field, and in the presence of small levels of internal flare. Results can then be compared with more conventional optical metrics such as Strehl ratio, partial coherence contrast, or image threshold CD. Results are presented for three commercial small field catadioptric 193 nm lithographic lenses. Aberration levels for each lens at several field positions and at several wavelengths has been described using 37. Zernike polynomial coefficients. Minimum aerial image requirements have been correlated to resist performance to allow the evaluation of various feature types, a unique situation when no mature 193 nm resist process existed. Additionally, the impact of modified illumination on aberrations is presented.
© (1998) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Bruce W. Smith, James E. Webb, John S. Petersen, Jeff Meute, "Aberration evaluation and tolerancing of 193-nm lithographic objective lenses", Proc. SPIE 3334, Optical Microlithography XI, (29 June 1998); doi: 10.1117/12.310756; https://doi.org/10.1117/12.310756
PROCEEDINGS
12 PAGES


SHARE
KEYWORDS
Nanoimprint lithography

Image processing

Photoresist processing

Monochromatic aberrations

Lithography

Lenses

Photoresist materials

Back to Top