Patent ID: 7994083

Claim:
A silica glass material capable of being used in the light path of the lithographic irradiation of lithographic devices operating at a wavelength of below about 300 nm doped with molecular hydrogen having an average molecular hydrogen concentration [H 2 ](avg) not lower than about 5×10 15 molecules/cm 3 and not higher than about 1×10 18 molecules/cm 3 , a maximal molecular hydrogen concentration [H 2 ](max) and a minimal molecular hydrogen concentration [H 2 ](min), wherein 0.10≦[H 2 ](min)/[H 2 ](max)≦0.95, and less than 0.3 ppm variation in index of refraction, and wherein the silica glass material has a LIWFD measured at 633 nm of between −1.0 and 1.0 nm/cm when subjected to 10 billion pulses of a laser at approximately 193 nm, the laser operating at a fluence of approximately 70 μJ/cm 2 .