Send to

Choose Destination

Links from PubMed

See comment in PubMed Commons below
Appl Opt. 2002 May 1;41(13):2508-13.

Absolute refractive indices and thermal coefficients of CaF2, SrF2, BaF2, and LiF near 157 nm.

Author information

National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8421, USA.


We present high-accuracy measurements for wavelengths near 157 nm of the absolute index of refraction, the index dispersion, and the temperature dependence of the index for the ultraviolet optical materials with cubic symmetry: CaF2, SrF2, BaF2, and LiF. Accurate values of these quantities for these materials are needed for designs of the lens systems for F2 excimer-laser-based exposure tools for 157-nm photolithography. These tools are expected to use CaF2 as the primary optical material and possibly one of the others to correct for chromatic aberrations. These optical properties were measured by the minimum deviation method. Absolute refractive indices were obtained with an absolute accuracy of 5 x 10(-6) to 6 x 10(-6).

PubMed Commons home

PubMed Commons


    Supplemental Content

    Full text links

    Icon for Optical Society of America
    Loading ...
    Support Center