A method for the preparation of ultra dry, cl - free and f - doped highly pure quartz glass

摘要

The present invention relates to a process for the production of an ultra dry, high-purity, cl - free, f - doped quartz glass. Silicon dioxide - powder or carbon black - preforms are for the formation of a glass under conditions are used, so that a desired level of an f - doping is provided, while the cl - and oh^--Concentrations be reduced on the tracks concentrations. The method includes the provision of a glass precursor the form of a silicon dioxide - powder or carbon black - preform. The powder is heated in an oven. The powder is compared with an f - species in a predetermined temperature and time which is sufficient in order to melt the powder and a highly pure quartz glass to form at the bottom of the furnace.