Options
2006
Journal Article
Titel
Bulk scattering properties of synthetic fused silica at 193 nm
Abstract
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 alpha between 0.6x10-3 and 1.7x10-3 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 about n8/lambda 4 as predicted by theory is obtained. Thus, the model is demonstrated to hold from the visible spectral range down to the deep ultraviolet.