ULE® Glass for EUVL applications, a fictive temperature correlation

Infrared peak positions were correlated to the fictive temperatures (Tf) of titania doped silica glasses as a function of titania content for glasses with between 7 and 8 wt.% TiO2. To establish fictive temperature, both the infrared peak position and the percent titania need to be known. The correlation was established by taking 1 mm thick slices of silica doped with 7.0, 7.3 and 7.7 wt.% TiO2, holding them isothermally until the structure comes into equilibrium with the hold temperature and then quenching the samples in room temperature water. Five hold temperatures between 900 and 1100 °C were used. A correlation was obtained with R2 values of > 0.98 for each TiO2 concentration.

► IR peak positions are correlated to fictive temperature of titania silicate glass. ► Titania content between 7 and 8 wt.% is studied at fictive temperatures between 900 and 1100 °C. ► A fictive temperature correlation is established for ULE® Glass with a low level of uncertainty.