Share Email Print

Proceedings Paper

Status of 157 nm lithography and prospects for immersion
Author(s): Kiyoshi Fujii; Takuya Hagiwara; Seiji Matsuura; Toshiyuki Ishimaru; Yoshihisa Matsubara; Wataru Wakamiya
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

The FPA-5800FS1 157-nm scanner installed at Selete has demonstrated a minimum resolution of 55 nm for line-and-space (L/S) patterns with a numerical aperture (NA) of 0.8. The scanner has been used for 65-nm-node device fabrication and will be used for 45-nm-node device development. The approximately 20% shorter wavelength in 157-nm lithography has several advantages compared to 193-nm immersion lithography. For example, assuming the same k1 value, 157-nm lithography, which has a 20% smaller NA, has a 25% larger depth of focus and better resolution in two-dimensional patterns, for which polarized illumination is not effective. This 157- nm immersion lithography has the potential to be used for 32-nm-node device fabrication with a k1 of 0.3 in combination with a high-refractive-index immersion fluid. To demonstrate the process feasibility of 157-nm immersion lithography, we developed a two-beam interferometric stepper with a high-quality F2 laser and used it and a commercial perfluoroether as an immersion fluid to print 60-nm L/S patterns with a steep cross-sectional profile. Development of an immersion fluid with a high refractive index and low optical absorption is critical issue for making 157-nm immersion lithography practical. We have identified several fluorinated polymers with high diffractive indices and will continue searching for suitable 157-nm immersion fluids.

Paper Details

Date Published: 12 May 2004
PDF: 11 pages
Proc. SPIE 5754, Optical Microlithography XVIII, (12 May 2004); doi: 10.1117/12.599455
Show Author Affiliations
Kiyoshi Fujii, Semiconductor Leading Edge Technologies, Inc. (Japan)
Takuya Hagiwara, Semiconductor Leading Edge Technologies, Inc. (Japan)
Seiji Matsuura, Semiconductor Leading Edge Technologies, Inc. (Japan)
Toshiyuki Ishimaru, Semiconductor Leading Edge Technologies, Inc. (Japan)
Yoshihisa Matsubara, Semiconductor Leading Edge Technologies, Inc. (Japan)
Wataru Wakamiya, Semiconductor Leading Edge Technologies, Inc. (Japan)

Published in SPIE Proceedings Vol. 5754:
Optical Microlithography XVIII
Bruce W. Smith, Editor(s)

© SPIE. Terms of Use
Back to Top