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AssigneeCorning Incorporated
InventorsDouglas C. Allan, Nicholas F. Borrelli, Charlene M. Smith, Robert W. Sparrow
Estimating the term…
The invention provides a UV below 200 nm lithography method. The invention includes providing a below 200 nm radiation source for producing <200-nm light, providing a plurality of mixed cubic fluoride crystal optical elements, with the fluoride crystals comprised of a combination of alkaline earth cations having different optical polarizabilities such as to produce an overall isotropic polarizability which minimizes the fluoride crystal spatial dispersion below 200 nm, transmitting <200-nm light through the cubic fluoride crystal optical elements, forming a lithography pattern with the light, reducing the lithography pattern and projecting the lithography pattern with the cubic fluoride crystal optical elements onto a UV radiation sensitive lithography printing medium to form a printed lithographic pattern. The invention includes making the mixed fluoride crystals and forming optical element therefrom.
A UV lithography method, said method comprising:
A mixed fluoride crystal for transmitting <200-nm light with a minimized amount of spatial dispersion, said mixed crystal having a cubic structure and comprised of a plurality of first metal cations and a plurality of second metal cations, said first metal cations having a high polarizability and said second metal cations having a low polarizability, said first metal cations providing an ability to impart positive spatial dispersion and said second metal cations providing an ability to impart negative spatial dispersion.
A mixed fluoride crystal for transmitting light below 200 nm light with a minimized amount of spatial dispersion, said crystal having a cubic structure and comprised of a plurality of first alkaline earth metal cations and a plurality of second alkaline earth metal cations and a plurality of third alkaline earth metal cations, said first alkaline earth metal cations having a high polarizability and said second alkaline earth metal cations having a low polarizability and said third alkaline earth metal cations having an intermediate polarizability, said first alkaline earth metal cations providing an ability to provide positive spatial dispersion to <200 nm light and said third alkaline earth metal cations providing a capacity to impart positive spatial dispersion to <200 nm light and said second alkaline earth metal cations providing an ability to impart negative intrinsic-birefringence to <200 nm light.
Dependencies are inferred from the claim text.