Share Email Print

Proceedings Paper

Implications of immersion lithography on 193-nm photoresists
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Immersion lithography has been proposed as a technique to print sub-100nm features using 193nm lithography. The process involves filling the space between the lens fixture of an exposure tool and the photoresist-coated silicon wafer with a liquid. In the case of immersion 193nm lithography, water can serve as that liquid. The immersion option raises questions about how photoresists and water interact. Components of the photoresist could be leached into the water, thus modifying the refractive index of the medium, depositing material on the lens, or altering the solubility switching process of the photoresist. Several phenomena could affect the optical properties of the resist and water and, ultimately, the resolution of the process. To better understand the impact that immersion lithography would have on photoresist performance, a study has been undertaken to measure the amount of resist components that are leached by water from model 193nm photoresists. The components studied were residual casting solvent (propylene glycol methyl ether acetate), the photoacid generator (triphenylsulfonium nonaflate), and the base quencher (triethanolamine). Since it was expected that only a small amount of each material would be leached into the water, 14C-labeled samples of each resist component were synthesized and added to the 193nm resists. Films of the labeled resists were coated onto a silicon wafer and immersed in water. The water was collected and the film was dissolved in casting solvent and collected. The amount of material leached into the water was determined by radiochemical analysis. Spectroscopic ellipsometry was also used to quantify changes in the optical constants of the resists and the water.

Paper Details

Date Published: 14 May 2004
PDF: 10 pages
Proc. SPIE 5376, Advances in Resist Technology and Processing XXI, (14 May 2004);
Show Author Affiliations
J. Christopher Taylor, Univ. of Texas/Austin (United States)
Charles R. Chambers, Univ. of Texas/Austin (United States)
Ryan Deschner, Univ. of Texas/Austin (United States)
Robert J. LeSuer, Univ. of Texas/Austin (United States)
Willard E. Conley, Motorola, Inc. (United States)
Sean D. Burns, Univ. of Texas/Austin (United States)
C. Grant Willson, Univ. of Texas/Austin (United States)

Published in SPIE Proceedings Vol. 5376:
Advances in Resist Technology and Processing XXI
John L. Sturtevant, 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?