 | | Starlith(TM) 400
The Starlith(TM) 400 optical system is used in the I-line  PAS 5500/400 Scanner from ASML.
It has been designed for the exposure wavelength 365 nm and provides a resolution of up to 0.28 µm.
As the radiation emitted by the mercury vapor lamp used lies in the UV range, special high-purity glass must be used for the up to 30 individual elements of the lens.
The demands made on the homogeneity of the refractive index lie in the ppm range. The image field is 26 mm x 33 mm, and the numerical aperture (NA) can be adjusted from 0.45 to 0.65. |