METHOD OF MAKING TITANIA-SILICA GLASS WITH UNIFORM HYDROXIDE CONCENTRATION

A process of forming a titania-silica glass body, the process including exposing a titania-doped silica soot body to a first thermal treatment by heating the body to a first temperature T1 between about 800°C and about 1100°C for a first time duration tl calculated using the equation: t1>Lc24α, wherein Lc is the characteristic length (cm) of the body and α is the thermal diffusivity (cm2/sec) of the body. The process further including exposing the body to a second thermal treatment by heating the body to a second temperature T2 between about 1050°C and about 1250°C wherein, after the second thermal treatment, a peak-to-valley difference of hydroxide concentration amongst a plurality of segments of the body is about 70 ppm or less.