The bulk scattering of synthetic fused silica for 193 nm lithography was investigated using an instrument for high-sensitive total and angle resolved scattering measurements at 193 nm. Bulk scattering coefficients α between 0.6×10-3 and 1.7×10-3 cm-1 (base e) depending on the hydroxyl (OH) content and fictive temperature of the samples were measured using a total scattering (TS) technique. The results are interpreted with regard to a model which relates scattering in fused silica to structural disorder in the material. From angle resolved scatter (ARS) measurements at 193 nm, a Rayleigh type scattering distribution was found. Using TS and ARS at 633 nm, 532 nm, and 325 nm in addition to the results at 193 nm, wavelength scaling ~n 8/λ 4 as predicted by theory is obtained. Thus, the model is demonstrated to hold from the visible spectral range down to the deep ultraviolet.
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