Paper
28 May 2004 Strong improvement of critical parameters of CaF2 lens blanks for 193-nm and 157-nm lithography
Author Affiliations +
Abstract
Homogeneity residuals of the refractive index have a strong influence on the performance of lithography tools for both 193 and 157 nm application wavelengths. By systematic investigations of various defects in the real structure of CaF2 crystals, the origin of homogeneity residuals can be shown. Based on a quantitative analysis we define limiting values for the individual defects which can be either tolerated or controlled by optimized process steps, e.g. annealing. These correlations were carried out for all three relevant main crystal lattice orientations of CaF2 blanks. In conclusion we achieved a strong improvement of the critical parameters of both refractive index homogeneity and striae for large size lens blanks up to 270mm diameter.
© (2004) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Guenter Grabosch, Lutz Parthier, Peter Kruell, and Konrad Knapp "Strong improvement of critical parameters of CaF2 lens blanks for 193-nm and 157-nm lithography", Proc. SPIE 5377, Optical Microlithography XVII, (28 May 2004); https://doi.org/10.1117/12.536310
Lens.org Logo
CITATIONS
Cited by 3 scholarly publications.
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Annealing

Crystals

Lens blanks

Refractive index

Lithography

Wavefronts

Photovoltaics

RELATED CONTENT


Back to Top