Development and evaluation of interface-stabilized and reactive-sputtered oxide-capped multilayers for EUV lithography
Michael Kriese, Jim Rodriguez, Gary Fournier, Steven Grantham, Shannon B. Hill, John J. Curry, Charles Tarrio, Yuriy Platonov
A critical component of high-performance EUV lithography source optics is the reflecting multilayer coating. The ideal multilayer will have both high reflectance and high stability to thermal load. Additionally the capping layers must provide resistance to degradations from exposure to an EUV source, and also be compatible with, or enhance, the systems used for cleaning an exposed multilayer coating. We will report on the results of development of C and B4C stabilized Mo/Si multilayers used to increase the as-deposited peak reflectivity (Rp) as well as decreasing the loss of peak reflectivity (Rp) as a function of annealing temperature. Previous results demonstrate that these layers prevent loss of Rp for temperatures up to 600º C. Results on the use of reactively-sputtered oxide capping layers such as TiO2 and ZrO2 will be presented as well, along with results of exposure testing. The deposition is performed in a dual process-chamber inline magnetron system, using reactive sputtering for the production of capping layers. The reflectometer and exposure apparatus at the NIST Physics Laboratory is used for evaluation of the performance. Exposure results on the resistance to oxidation in the presence of water vapor will be presented and discussed.
, Rodriguez, J.
, Fournier, G.
, Grantham, S.
, Hill, S.
, Curry, J.
, Tarrio, C.
and Platonov, Y.
Development and evaluation of interface-stabilized and reactive-sputtered oxide-capped multilayers for EUV lithography, Proceedings of SPIE, [online], https://doi.org/10.1117/12.2085934
(Accessed December 2, 2023)